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DESCRIPTION Fluorouracil Cream, USP 5% is a topical preparation containing the fluorinated pyrimidine 5-fluorouracil, an antineoplastic antimetabolite. Fluorouracil Cream, USP contains 5% fluorouracil in a cream base consisting of methylparaben, polysorbate 60, propylene glycol, propylparaben, purified water, stearyl alcohol and white petrolatum. Chemically, fluorouracil is 5-fluoro-2,4(1 H ,3 H )-pyrimidinedione. It is a white to practically white crystalline powder which is sparingly soluble in water and slightly soluble in alcohol. One gram of fluorouracil is soluble in 100 mL of propylene glycol. The molecular weight of 5-fluorouracil is 130.08 and the structural formula is: str

CLINICAL PHARMACOLOGY There is evidence that the metabolism of fluorouracil in the anabolic pathway blocks the methylation reaction of deoxyuridylic acid to thymidylic acid. In this manner, fluorouracil interferes with the synthesis of deoxyribonucleic acid (DNA) and to a lesser extent inhibits the formation of ribonucleic acid (RNA). Since DNA and RNA are essential for cell division and growth, the effect of fluorouracil may be to create a thymine deficiency which provokes unbalanced growth and death of the cell. The effects of DNA and RNA deprivation are most marked on those cells which grow more rapidly and take up fluorouracil at a more rapid rate. The catabolic metabolism of fluorouracil results in degradation products (e.g., CO 2 , urea, α-fluoro-β-alanine) which are inactive. Systemic absorption studies of topically applied fluorouracil have been performed on patients with actinic keratoses using tracer amounts of 14 C- labeled fluorouracil added to a 5% preparation. All patients had been receiving nonlabeled fluorouracil until the peak of the inflammatory reaction occurred (2 to 3 weeks), ensuring that the time of maximum absorption was used for measurement. One gram of labeled preparation was applied to the entire face and neck and left in place for 12 hours. Urine samples were collected. At the end of 3 days, the total recovery ranged between 0.48% and 0.94% with an average of 0.76%, indicating that approximately 5.98% of the topical dose was absorbed systemically. If applied twice daily, this would indicate systemic absorption of topical fluorouracil to be in the range of 5 to 6 mg per daily dose of 100 mg. In an additional study, negligible amounts of labeled material were found in plasma, urine, and expired CO2 after 3 days of treatment with topically applied 14 C-labeled fluorouracil.

INDICATIONS AND USAGE Fluorouracil is recommended for the topical treatment of multiple actinic or solar keratoses. In the 5% strength, it is also useful in the treatment of superficial basal cell carcinomas when conventional methods are impractical, such as with multiple lesions or difficult treatment sites. Safety and efficacy in other indications have not been established. The diagnosis should be established prior to treatment, since this method has not been proven effective in other types of basal cell carcinomas. With isolated, easily accessible basal cell carcinomas, surgery is preferred since success with such lesions is almost 100%. The success rate with fluorouracil cream is approximately 93%, based on 113 lesions in 54 patients. Eighty-eight lesions treated with the cream produced 7 failures.

CONTRAINDICATIONS Fluorouracil may cause fetal harm when administered to a pregnant woman. There are no adequate and well-controlled studies in pregnant women with either the topical or the parenteral forms of fluorouracil. One birth defect (cleft lip and palate) has been reported in the newborn of a patient using fluorouracil as recommended. One birth defect (ventricular septal defect) and cases of miscarriage have been reported when fluorouracil was applied to mucous membrane areas. Multiple birth defects have been reported in a fetus of a patient treated with intravenous fluorouracil. Animal reproduction studies have not been conducted with fluorouracil. Fluorouracil administered parenterally has been shown to be teratogenic in mice, rats, and hamsters when given at doses equivalent to the usual human intravenous dose; however, the amount of fluorouracil absorbed systemically after topical administration to actinic keratoses is minimal (see CLINICAL PHARMACOLOGY ). Fluorouracil exhibited maximum teratogenicity when given to mice as single intraperitoneal injections of 10 to 40 mg/kg on Day 10 or 12 of gestation. Similarly, intraperitoneal doses of 12 to 37 mg/kg given to rats between Days 9 and 12 of gestation and intramuscular doses of 3 to 9 mg/kg given to hamsters between Days 8 and 11 of gestation were teratogenic and/or embryotoxic (i.e., resulted in increased resorptions or embryolethality). In monkeys, divided doses of 40 mg/kg given between Days 20 and 24 of gestation were not teratogenic. Doses higher than 40 mg/kg resulted in abortion. Fluorouracil should not be used in patients with dihydropyrimidine dehydrogenase (DPD) enzyme deficiency. A large percentage of fluorouracil is catabolized by the DPD enzyme. DPD enzyme deficiency can result in shunting of fluorouracil to the anabolic pathway, leading to cytotoxic activity and potential toxicities. Fluorouracil is contraindicated in women who are or may become pregnant during therapy. If this drug is used during pregnancy, or if the patient becomes pregnant while using this drug, the patient should be apprised of the potential hazard to the fetus. Fluorouracil is also contraindicated in patients with known hypersensitivity to any of its components.

WARNINGS Application to mucous membranes should be avoided due to the possibility of local inflammation and ulceration. Additionally, cases of miscarriage and a birth defect (ventricular septal defect) have been reported when fluorouracil was applied to mucous membrane areas during pregnancy . Occlusion of the skin with resultant hydration has been shown to increase percutaneous penetration of several topical preparations. If any occlusive dressing is used in treatment of basal cell carcinoma, there may be an increase in the severity of inflammatory reactions in the adjacent normal skin. A porous gauze dressing may be applied for cosmetic reasons without increase in reaction. Exposure to ultraviolet rays should be minimized during and immediately following treatment with fluorouracil because the intensity of the reaction may be increased. Patients should discontinue therapy with fluorouracil if symptoms of DPD enzyme deficiency develop (see CONTRAINDICATIONS ). Rarely, life-threatening toxicities such as stomatitis, diarrhea, neutropenia, and neurotoxicity have been reported with intravenous administration of fluorouracil in patients with DPD enzyme deficiency. One case of life-threatening systemic toxicity has been reported with the topical use of fluorouracil in a patient with DPD enzyme deficiency. Symptoms included severe abdominal pain, bloody diarrhea, vomiting, fever, and chills. Physical examination revealed stomatitis, erythematous skin rash, neutropenia, thrombocytopenia, inflammation of the esophagus, stomach, and small bowel. Although this case was observed with 5% fluorouracil cream, it is unknown whether patients with profound DPD enzyme deficiency would develop systemic toxicity with lower concentrations of topically applied fluorouracil.

PRECAUTIONS General There is a possibility of increased absorption through ulcerated or inflamed skin. Information for Patients Patients should be forewarned that the reaction in the treated areas may be unsightly during therapy and, usually, for several weeks following cessation of therapy. Patients should be instructed to avoid exposure to ultraviolet rays during and immediately following treatment with fluorouracil because the intensity of the reaction may be increased. If fluorouracil is applied with the fingers, the hands should be washed immediately afterward. Fluorouracil should not be applied on the eyelids or directly into the eyes, nose, or mouth because irritation may occur. Fluorouracil, including fluorouracil cream, may be fatal if ingested by pets. Avoid allowing pets to contact the fluorouracil cream container or the skin where fluorouracil cream has been applied. Store fluorouracil cream out of reach of pets. Safely discard or clean any cloth or applicator that may retain fluorouracil cream and avoid leaving any residues of fluorouracil cream on your hands, clothing, carpeting or furniture. Laboratory Tests Solar keratoses which do not respond should be biopsied to confirm the diagnosis. Follow-up biopsies should be performed as indicated in the management of superficial basal cell carcinoma. Carcinogenesis, Mutagenesis, Impairment of Fertility Adequate long-term studies in animals to evaluate carcinogenic potential have not been conducted with fluorouracil. Studies with the active ingredient of fluorouracil, 5-fluorouracil, have shown positive effects in in vitro tests for mutagenicity and on impairment of fertility. 5-Fluorouracil was positive in three in vitro cell neoplastic transformation assays. In the C3H/10T½ clone 8 mouse embryo cell system, the resulting morphologically transformed cells formed tumors when inoculated into immunosuppressed syngeneic mice. While no evidence for mutagenic activity was observed in the Ames test (three studies), fluorouracil has been shown to be mutagenic in the survival count rec-assay with Bacillus subtilis and in the Drosophila wing-hair spot test. Fluorouracil produced petite mutations in Saccharomyces cerevisiae and was positive in the micronucleus test (bone marrow cells of male mice). Fluorouracil was clastogenic in vitro (i.e., chromatid gaps, breaks, and exchanges) in Chinese hamster fibroblasts at concentrations of 1.0 and 2.0 mcg/mL and has been shown to increase sister chromatid exchange in vitro in human lymphocytes. In addition, 5-fluorouracil has been reported to produce an increase in numerical and structural chromosome aberrations in peripheral lymphocytes of patients treated with this product. Doses of 125 to 250 mg/kg, administered intraperitoneally, have been shown to induce chromosomal aberrations and changes in chromosome organization of spermatogonia in rats. Spermatogonial differentiation was also inhibited by fluorouracil, resulting in transient infertility. However, in studies with a strain of mouse which is sensitive to the induction of sperm head abnormalities after exposure to a range of chemical mutagens and carcinogens, fluorouracil was inactive at oral doses of 5 to 80 mg/kg/day.

differentiation was also inhibited by fluorouracil, resulting in transient infertility. However, in studies with a strain of mouse which is sensitive to the induction of sperm head abnormalities after exposure to a range of chemical mutagens and carcinogens, fluorouracil was inactive at oral doses of 5 to 80 mg/kg/day. In female rats, fluorouracil administered intraperitoneally at doses of 25 and 50 mg/kg during the preovulatory phase of oogenesis significantly reduced the incidence of fertile matings, delayed the development of preimplantation and postimplantation embryos, increased the incidence of preimplantation lethality and induced chromosomal anomalies in these embryos. Single-dose intravenous and intraperitoneal injections of 5-fluorouracil have been reported to kill differentiated spermatogonia and spermatocytes (at 500 mg/kg) and to produce abnormalities in spermatids (at 50 mg/kg) in mice. Pregnancy See CONTRAINDICATIONS. Nursing Mothers It is not known whether fluorouracil is excreted in human milk. Because there is some systemic absorption of fluorouracil after topical administration (see CLINICAL PHARMACOLOGY ), because many drugs are excreted in human milk, and because of the potential for serious adverse reactions in nursing infants, a decision should be made whether to discontinue nursing or to discontinue use of the drug, taking into account the importance of the drug to the mother. Pediatric Use Safety and effectiveness in children have not been established.

Information for Patients Patients should be forewarned that the reaction in the treated areas may be unsightly during therapy and, usually, for several weeks following cessation of therapy. Patients should be instructed to avoid exposure to ultraviolet rays during and immediately following treatment with fluorouracil because the intensity of the reaction may be increased. If fluorouracil is applied with the fingers, the hands should be washed immediately afterward. Fluorouracil should not be applied on the eyelids or directly into the eyes, nose, or mouth because irritation may occur. Fluorouracil, including fluorouracil cream, may be fatal if ingested by pets. Avoid allowing pets to contact the fluorouracil cream container or the skin where fluorouracil cream has been applied. Store fluorouracil cream out of reach of pets. Safely discard or clean any cloth or applicator that may retain fluorouracil cream and avoid leaving any residues of fluorouracil cream on your hands, clothing, carpeting or furniture.

Laboratory Tests Solar keratoses which do not respond should be biopsied to confirm the diagnosis. Follow-up biopsies should be performed as indicated in the management of superficial basal cell carcinoma.

Carcinogenesis, Mutagenesis, Impairment of Fertility Adequate long-term studies in animals to evaluate carcinogenic potential have not been conducted with fluorouracil. Studies with the active ingredient of fluorouracil, 5-fluorouracil, have shown positive effects in in vitro tests for mutagenicity and on impairment of fertility. 5-Fluorouracil was positive in three in vitro cell neoplastic transformation assays. In the C3H/10T½ clone 8 mouse embryo cell system, the resulting morphologically transformed cells formed tumors when inoculated into immunosuppressed syngeneic mice. While no evidence for mutagenic activity was observed in the Ames test (three studies), fluorouracil has been shown to be mutagenic in the survival count rec-assay with Bacillus subtilis and in the Drosophila wing-hair spot test. Fluorouracil produced petite mutations in Saccharomyces cerevisiae and was positive in the micronucleus test (bone marrow cells of male mice). Fluorouracil was clastogenic in vitro (i.e., chromatid gaps, breaks, and exchanges) in Chinese hamster fibroblasts at concentrations of 1.0 and 2.0 mcg/mL and has been shown to increase sister chromatid exchange in vitro in human lymphocytes. In addition, 5-fluorouracil has been reported to produce an increase in numerical and structural chromosome aberrations in peripheral lymphocytes of patients treated with this product. Doses of 125 to 250 mg/kg, administered intraperitoneally, have been shown to induce chromosomal aberrations and changes in chromosome organization of spermatogonia in rats. Spermatogonial differentiation was also inhibited by fluorouracil, resulting in transient infertility. However, in studies with a strain of mouse which is sensitive to the induction of sperm head abnormalities after exposure to a range of chemical mutagens and carcinogens, fluorouracil was inactive at oral doses of 5 to 80 mg/kg/day. In female rats, fluorouracil administered intraperitoneally at doses of 25 and 50 mg/kg during the preovulatory phase of oogenesis significantly reduced the incidence of fertile matings, delayed the development of preimplantation and postimplantation embryos, increased the incidence of preimplantation lethality and induced chromosomal anomalies in these embryos. Single-dose intravenous and intraperitoneal injections of 5-fluorouracil have been reported to kill differentiated spermatogonia and spermatocytes (at 500 mg/kg) and to produce abnormalities in spermatids (at 50 mg/kg) in mice.

Nursing Mothers It is not known whether fluorouracil is excreted in human milk. Because there is some systemic absorption of fluorouracil after topical administration (see CLINICAL PHARMACOLOGY ), because many drugs are excreted in human milk, and because of the potential for serious adverse reactions in nursing infants, a decision should be made whether to discontinue nursing or to discontinue use of the drug, taking into account the importance of the drug to the mother.

ADVERSE REACTIONS The most frequent adverse reactions to fluorouracil occur locally and are often related to an extension of the pharmacological activity of the drug. These include burning, crusting, allergic contact dermatitis, pruritus, scarring, rash, soreness, and ulceration. Ulcerations, other local reactions, cases of miscarriage, and a birth defect (ventricular septal defect) have been reported when fluorouracil was applied to mucous membrane areas. Leukocytosis is the most frequent hematological side effect. Although a causal relationship is remote, other adverse reactions which have been reported infrequently are: Central Nervous System: Emotional upset, insomnia, irritability. Gastrointestinal: Medicinal taste, stomatitis. Hematological: Eosinophilia, thrombocytopenia, toxic granulation. Integumentary : Alopecia, blistering, bullous pemphigoid, discomfort, ichthyosis, scaling, suppuration, swelling, telangiectasia, tenderness, urticaria, skin rash. Special Senses: Conjunctival reaction, corneal reaction, lacrimation, nasal irritation. Miscellaneous: Herpes simplex. To report SUSPECTED ADVERSE REACTIONS, contact Encube Ethicals Private Limited at 1-833-285-4151 and/or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch.

OVERDOSAGE There have been no reports of overdosage with fluorouracil. The oral LD 50 for the 5% topical cream was 234 mg/kg in rats and 39 mg/kg in dogs. These doses represented 11.7 and 1.95 mg/kg of fluorouracil, respectively. Studies with a 5% topical solution yielded an oral LD 50 of 214 mg/kg in rats and 28.5 mg/kg in dogs, corresponding to 10.7 and 1.43 mg/kg of fluorouracil, respectively. The topical application of the 5% cream to rats yielded an LD 50 of greater than 500 mg/kg.

DOSAGE AND ADMINISTRATION When Fluorouracil Cream, USP 5% is applied to a lesion, a response occurs with the following sequence: erythema, usually followed by vesiculation, desquamation, erosion, and re-epithelialization. Fluorouracil Cream, USP 5% should be applied preferably with a nonmetal applicator or suitable glove. If fluorouracil is applied with the fingers, the hands should be washed immediately afterward. Actinic or Solar Keratosis: Apply cream twice daily in an amount sufficient to cover the lesions. Medication should be continued until the inflammatory response reaches the erosion stage, at which time use of the drug should be terminated. The usual duration of therapy is from 2 to 4 weeks. Complete healing of the lesions may not be evident for 1 to 2 months following cessation of fluorouracil therapy. Superficial Basal Cell Carcinomas: Only the 5% strength is recommended . Apply cream twice daily in an amount sufficient to cover the lesions. Treatment should be continued for at least 3 to 6 weeks. Therapy may be required for as long as 10 to 12 weeks before the lesions are obliterated. As in any neoplastic condition, the patient should be followed for a reasonable period of time to determine if a cure has been obtained.

HOW SUPPLIED Fluorouracil Cream, USP 5% is available in 40 g tubes containing 5% fluorouracil (NDC 21922-049-17) in a vanishing cream base consisting of methylparaben, polysorbate 60, propylene glycol, propylparaben, purified water, stearyl alcohol, and white petrolatum. Store at 25°C (77°F); excursions permitted to 15°C to 30°C (59°F to 86°F) Manufactured by: Encube Ethicals Pvt. Ltd. Plot No. C1, Madkaim Industrial Estate, Madkaim, Post: Mardol, Ponda, Goa - 403 404, India. Distributed by: Encube Ethicals, Inc. 200 Meredith Drive, Suite 202, Durham, NC 27713 USA Revised: 01/2025

1 INDICATIONS AND USAGE Tolak (fluorouracil) Cream is indicated for the topical treatment of actinic keratosis lesions of the face, ears, and/or scalp. Tolak (fluorouracil) Cream, 4%, is a nucleoside metabolic inhibitor indicated for the topical treatment of actinic keratosis lesions of the face, ears, and scalp ( 1 ).

2 DOSAGE AND ADMINISTRATION Prior to application of Tolak Cream, wash, rinse, and dry the treatment areas. Apply Tolak Cream once daily in an amount sufficient to cover the lesions of the face, ears, and/or scalp with a thin film, using the fingertips to gently massage the medication uniformly into the skin. Apply Tolak Cream for a period of 4 weeks as tolerated. Thoroughly wash hands following Tolak Cream application. Tolak Cream is for topical use only. Do not apply to eyes, nose, mouth or mucous membranes. Not for ophthalmic, oral or intravaginal use. Apply Tolak Cream after washing, rinsing, and drying the treatment area(s) ( 2 ). Apply Tolak Cream once daily in an amount sufficient to cover the lesions of the face, ears, and/or scalp with a thin film, using the fingertips to gently massage the medication uniformly into the skin ( 2 ). Tolak Cream should be applied for a period of 4 weeks as tolerated ( 2 ). Wash hands thoroughly following Tolak Cream application ( 2 ). Tolak Cream is for topical use only. Do not apply to eyes, nose, mouth or mucous membranes ( 2 ). Not for ophthalmic, oral, or intravaginal use ( 2 ).

4 CONTRAINDICATIONS Tolak Cream is contraindicated: During pregnancy [see Warnings and Precautions (5.5 , 8.1) ] In patients with dihydropyrimidine dehydrogenase (DPD) deficiency [see Warnings and Precautions (5.6) ] Pregnancy ( 4.1 , 8.1 ). Dihydropyrimidine dehydrogenase (DPD) deficiency ( 4.2 ). 4.1 Pregnancy Tolak Cream may cause fetal harm when administered during pregnancy and is contraindicated in women who are pregnant. If this drug is used during pregnancy, or if the patient becomes pregnant while using this drug, the patient should be apprised of the potential hazard to the fetus. 4.2 Dihydropyrimidine Dehydrogenase Deficiency Tolak Cream is contraindicated in patients with dihydropyrimidine dehydrogenase (DPD) deficiency.

5 WARNINGS AND PRECAUTIONS Application site adverse reactions are likely to occur during and for 4 weeks after treatment of actinic keratosis with Tolak Cream ( 5.1 ). Hypersensitivity reactions may occur with Tolak Cream ( 5.2 ). Avoid treatment in the periocular area. Eye disorders, including corneal reactions have occurred with topical fluorouracil use. Avoid accidental transfer of the drug into eyes and to the periocular area. If accidental exposure occurs, seek medical care ( 5.3 ). Increased sensitivity to ultraviolet light may occur during and immediately after treatment with Tolak Cream ( 5.4 ). Fluorouracil may cause fetal harm when administered to a pregnant woman. Advise females of reproductive potential to use effective contraception ( 5.5 ). Increased fluorouracil exposures may occur in DPD deficiency. Discontinue Tolak Cream if symptoms of fluorouracil's systemic toxicity develop ( 5.6 ). 5.1 Application Site Adverse Reactions Application site reactions (erythema, scaling/dryness, edema, crusting, erosions, stinging/burning, and pruritus) were observed in almost all patients during treatment of actinic keratosis on the face, ears, and/or scalp with topical fluorouracil [see Adverse Reactions (6.1) ] . In the clinical trials of Tolak Cream, application site irritation returned to baseline (pre-treatment) levels within 4 weeks after discontinuing treatment. Do not apply Tolak Cream directly into eyes, nose, mouth, or other mucous membranes because irritation, local inflammation and ulceration can occur. 5.2 Hypersensitivity Reactions Allergic contact dermatitis (delayed type hypersensitivity reaction) has been noted for topical fluorouracil drugs. While application site reactions are observed in almost all patients during treatment of actinic keratosis with topical fluorouracil [see Adverse Reactions (6.2) ] , delayed type hypersensitivity should be suspected in the event of severe pruritus or eczema at the application site or at a distant site. Although the potential for a delayed hypersensitivity reaction to fluorouracil exists, patch testing to confirm hypersensitivity may be inconclusive. Tolak Cream contains peanut oil. If signs of hypersensitivity occur, patients should discontinue Tolak Cream immediately and contact their healthcare provider. 5.3 Ophthalmic Adverse Reactions Corneal and conjunctival disorders have occurred with topical fluorouracil use [see Adverse Reactions (6.2) ] . Avoid application to the periocular area. To avoid transfer of the drug into the eyes and to the periocular area during and after application, patients should wash hands well after applying Tolak Cream. If accidental exposure occurs, the patient should flush eye(s) with large amounts of water and seek medical care as soon as possible. 5.4 Photosensitivity Topical fluorouracil is associated with photosensitivity reactions including severe sunburn. Minimize exposure to ultraviolet rays including sunlight, sun lamps, and tanning beds during and immediately following treatment with Tolak Cream because the intensity of the photosensitivity reaction may be increased. 5.5 Embryofetal Toxicity Cases of miscarriage and birth defects (including cleft lip and cleft palate) have been reported when pregnant women were exposed to a topical or parenteral fluorouracil product.

iately following treatment with Tolak Cream because the intensity of the photosensitivity reaction may be increased. 5.5 Embryofetal Toxicity Cases of miscarriage and birth defects (including cleft lip and cleft palate) have been reported when pregnant women were exposed to a topical or parenteral fluorouracil product. In addition, ventricular septal defect and cases of miscarriage occurred when pregnant women applied a topical fluorouracil product to mucous membranes (Tolak Cream is not indicated for use on the mucous membrane). Furthermore, fluorouracil interferes with the synthesis of deoxyribonucleic acid (DNA), inhibits the formation of ribonucleic acid (RNA), and provokes unbalanced growth and death of cells. Therefore, Tolak Cream is contraindicated in pregnancy. Advise females of reproductive potential to use effective contraception during Tolak use and for one month after the last dose of Tolak Cream . 5.6 Toxicity in Patients with Dihydropyrimidine Dehydrogenase Deficiency Life-threatening systemic toxicity has been reported with the topical use of fluorouracil in a patient with DPD deficiency. Symptoms included severe abdominal pain, bloody diarrhea, vomiting, fever, and chills. Physical examination revealed stomatitis, erythematous skin rash, neutropenia, thrombocytopenia, inflammation of the esophagus, stomach and small bowel. A large percentage of fluorouracil is catabolized by the DPD enzyme. DPD enzyme deficiency may result in increased availability of fluorouracil to the anabolic pathway, which may lead to increased interference with DNA and RNA synthesis and increased cytotoxic activity and potential toxicities [see Clinical Pharmacology (12.1) ] . Therefore, Tolak Cream is contraindicated in patients with DPD deficiency. Patients should discontinue Tolak Cream if symptoms of fluorouracil's systemic toxicity develop.

6 ADVERSE REACTIONS The following serious adverse reactions are discussed in more detail in other sections of the labeling: Application Site Adverse Reactions [see Warnings and Precautions (5.1) ] Hypersensitivity Reactions [see Warnings and Precautions (5.2) ] Ophthalmic Adverse Reactions [see Warnings and Precautions (5.3) ] Photosensitivity [see Warnings and Precautions (5.4) ] Embryofetal toxicity [see Warnings and Precautions (5.5) ] Toxicity in Patients with Dihydropyrimidine Dehydrogenase Deficiency [see Warnings and Precautions (5.6) ] The most common (incidence > 68%) adverse reactions occur at the application site and include erythema, scaling/dryness, crusting, pruritus, stinging/burning, edema, and erosions. Erythema is observed in 99% of patients with actinic keratosis treated with Tolak Cream ( 6.1 ). To report SUSPECTED ADVERSE REACTIONS, contact Hill Dermaceuticals at 1-800-344-5707 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch . 6.1 Clinical Trials Experience Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of a drug cannot be directly compared to rates in the clinical trials of another drug and may not reflect the rates observed in practice. The data described below reflect exposure to Tolak Cream in 397 subjects with actinic keratosis in vehicle-controlled trials. The population ranged in age from 33 to 94 years, was 80% male, and almost all were Caucasian. Most subjects were treated with Tolak Cream once daily for 4 weeks. Throughout the 4-week treatment and the 4-week post-treatment periods, the trials specifically monitored for adverse reactions related to tolerability, including erythema, scaling/dryness, edema, crusting, erosions, stinging/burning, and pruritus. The number and percentage of subjects with each of these monitored adverse reactions at one or more post-baseline visit(s) during the clinical trials are shown in Table 1. Table 1: Incidence of Application Site Adverse Reactions Occurring with 4 Weeks of Tolak Cream Treatment in Clinical Trials 1 and 2 Tolak Cream N=397 n (%) Vehicle N=120 n (%) Mild, Moderate or Severe Severe Only Mild, Moderate or Severe Severe Only Erythema 394 (99%) 174 (44%) 102 (85%) 0 (0%) Scaling/ Dryness 377 (95%) 94 (24%) 99 (83%) 0 (0%) Crusting 346 (87%) 87 (22%) 46 (38%) 0 (0%) Pruritus 337 (85%) 65 (16%) 46 (38%) 1 (1%) Stinging/ Burning 346 (87%) 101 (25%) 42 (35%) 0 (0%) Edema 275 (69%) 30 (8%) 11 (9%) 0 (0%) Erosions 271 (68%) 44 (11%) 14 (12%) 0 (0%) In these clinical trials, the intensity of the adverse reactions in subjects using Tolak Cream generally increased over the 4-week treatment period, usually reaching maximal levels at 4 weeks of treatment and then diminishing to baseline levels within 4 weeks after cessation of treatment. In Trials 1 and 2, 11% of Tolak Cream-treated and 3% of vehicle-treated subjects discontinued treatment because of adverse reactions. Of these subjects, the majority had adverse reactions at the application site. Eye swelling, leading to discontinuation, occurred in one subject with Tolak Cream use . 6.2 Postmarketing Experience The following adverse reactions have been identified during post-approval use of topical fluorouracil. Because these reactions are reported voluntarily from a population of uncertain size, it is not always possible to reliably estimate their frequency or establish a causal relationship to drug exposure.

ting Experience The following adverse reactions have been identified during post-approval use of topical fluorouracil. Because these reactions are reported voluntarily from a population of uncertain size, it is not always possible to reliably estimate their frequency or establish a causal relationship to drug exposure. Blood and Lymphatic System Disorders : leukocytosis, pancytopenia, thrombocytopenia, eosinophilia, neutrophil toxic granulation Eye disorders : corneal disorder, conjunctival disorder, eye irritation, conjunctivitis, lacrimation Gastrointestinal disorders : stomatitis General Disorders and Administration Site Conditions : medicinal taste Infections and Infestations : herpes simplex Neoplasms : chronic lymphocytic leukemia, non-melanoma skin cancer Nervous system disorders : insomnia, irritability Psychiatric disorders : emotional distress Skin and subcutaneous tissue disorders : blistering, allergic contact dermatitis, photosensitivity, pain, scarring, skin irritation, rash, ulceration, hyperpigmentation, alopecia, bullous pemphigoid, ichthyosis, suppuration, swelling, soreness, telangiectasia, tenderness, urticaria

<table width="75%"><caption>Table 1: Incidence of Application Site Adverse Reactions Occurring with 4 Weeks of Tolak Cream Treatment in Clinical Trials 1 and 2</caption><col width="24%" align="left" valign="top"/><col width="19%" align="left" valign="top"/><col width="19%" align="left" valign="top"/><col width="19%" align="left" valign="top"/><col width="19%" align="left" valign="top"/><thead><tr styleCode="Botrule"><th styleCode="Lrule Rrule"/><th align="center" styleCode="Rrule" colspan="2">Tolak Cream N=397 n (%)</th><th align="center" styleCode="Rrule" colspan="2">Vehicle N=120 n (%)</th></tr><tr><th styleCode="Lrule Rrule"/><th styleCode="Rrule">Mild, Moderate or Severe</th><th styleCode="Rrule">Severe Only</th><th styleCode="Rrule">Mild, Moderate or Severe</th><th styleCode="Rrule">Severe Only</th></tr></thead><tbody><tr styleCode="Botrule"><td styleCode="Lrule Rrule">Erythema </td><td styleCode="Rrule">394 (99%)</td><td styleCode="Rrule">174 (44%)</td><td styleCode="Rrule">102 (85%)</td><td styleCode="Rrule">0 (0%)</td></tr><tr styleCode="Botrule"><td styleCode="Lrule Rrule">Scaling/ Dryness</td><td styleCode="Rrule">377 (95%)</td><td styleCode="Rrule">94 (24%)</td><td styleCode="Rrule">99 (83%)</td><td styleCode="Rrule">0 (0%)</td></tr><tr styleCode="Botrule"><td styleCode="Lrule Rrule">Crusting</td><td styleCode="Rrule">346 (87%)</td><td styleCode="Rrule">87 (22%)</td><td styleCode="Rrule">46 (38%)</td><td styleCode="Rrule">0 (0%)</td></tr><tr styleCode="Botrule"><td styleCode="Lrule Rrule">Pruritus</td><td styleCode="Rrule">337 (85%)</td><td styleCode="Rrule">65 (16%)</td><td styleCode="Rrule">46 (38%)</td><td styleCode="Rrule">1 (1%)</td></tr><tr styleCode="Botrule"><td styleCode="Lrule Rrule">Stinging/ Burning</td><td styleCode="Rrule">346 (87%)</td><td styleCode="Rrule">101 (25%)</td><td styleCode="Rrule">42 (35%)</td><td styleCode="Rrule">0 (0%)</td></tr><tr styleCode="Botrule"><td styleCode="Lrule Rrule">Edema</td><td styleCode="Rrule">275 (69%)</td><td styleCode="Rrule">30 (8%)</td><td styleCode="Rrule">11 (9%)</td><td styleCode="Rrule">0 (0%)</td></tr><tr><td styleCode="Lrule Rrule">Erosions</td><td styleCode="Rrule">271 (68%)</td><td styleCode="Rrule">44 (11%)</td><td styleCode="Rrule">14 (12%)</td><td styleCode="Rrule">0 (0%)</td></tr></tbody></table>

7 DRUG INTERACTIONS Subjects using systemic steroids, immunosuppressants, and immunomodulators were generally excluded from the clinical studies of Tolak Cream, as were subjects who used retinoids, topical steroids, glycolic acid products, alpha-hydroxy products, and chemical peeling products in the treatment areas. No clinical trials were designed to specifically evaluate drug interactions.

8 USE IN SPECIFIC POPULATIONS 8.1 Pregnancy Teratogenic Effects: Pregnancy Category X [see Contraindications (4.1) ] . Cases of miscarriage and birth defects (including cleft lip and cleft palate) have been reported when pregnant women were exposed to a topical or parenteral fluorouracil product. In addition, ventricular septal defect and cases of miscarriage occurred when pregnant women applied a topical fluorouracil product to mucous membranes (Tolak Cream is not indicated for use on the mucous membrane). Animal reproduction studies have not been conducted with Tolak Cream. Fluorouracil administered parenterally has been shown to be teratogenic in mice, rats, and hamsters when given at doses equivalent to the usual human intravenous dose. However, the amount of fluorouracil absorbed systemically after topical administration to actinic keratosis is minimal [see Clinical Pharmacology (12.3) ] . Fluorouracil exhibited maximum teratogenicity when given to mice as single intraperitoneal injections of 10 to 40 mg/kg on day 10 or 12 of gestation. Similarly, intraperitoneal doses of 12 to 37 mg/kg given to rats between days 9 and 12 of gestation and intramuscular doses of 3 to 9 mg/kg given to hamsters between days 8 and 11 of gestation were teratogenic and/or embryotoxic (i.e., resulted in increased resorptions or embryolethality). In monkeys, divided doses of 40 mg/kg given between days 20 and 24 of gestation were not teratogenic. However, doses higher than 40 mg/kg resulted in spontaneous abortions. Based on the recommended human dose and instructions for use, it is not possible to calculate human dose equivalents for animal exposures in these studies. 8.3 Nursing Mothers Because many drugs are excreted in human milk and there is some systemic absorption of fluorouracil after topical administration, and because of the potential for serious adverse reactions in nursing infants, a decision should be made whether to discontinue nursing or to discontinue drug use, taking into account the importance of the drug to the mother. 8.4 Pediatric Use Actinic keratosis is not usually observed in the pediatric population except in the case of rare genetic diseases. Tolak Cream is not intended for use in pediatric patients. Safety and effectiveness in children have not been established. 8.5 Geriatric Use No dose adjustment is required for elderly patients [see Clinical Studies (14) ] . The mean age of the 403 subjects treated with Tolak Cream in the clinical trials was 68 years. Of the Tolak Cream-treated subjects, 61% were 65 and over, while 28% were 75 and over. No overall differences in safety or effectiveness were observed between these subjects and younger subjects, and other reported clinical experience has not identified differences in responses between the elderly and younger patients, but greater sensitivity of some older individuals cannot be ruled out.

8.1 Pregnancy Teratogenic Effects: Pregnancy Category X [see Contraindications (4.1) ] . Cases of miscarriage and birth defects (including cleft lip and cleft palate) have been reported when pregnant women were exposed to a topical or parenteral fluorouracil product. In addition, ventricular septal defect and cases of miscarriage occurred when pregnant women applied a topical fluorouracil product to mucous membranes (Tolak Cream is not indicated for use on the mucous membrane). Animal reproduction studies have not been conducted with Tolak Cream. Fluorouracil administered parenterally has been shown to be teratogenic in mice, rats, and hamsters when given at doses equivalent to the usual human intravenous dose. However, the amount of fluorouracil absorbed systemically after topical administration to actinic keratosis is minimal [see Clinical Pharmacology (12.3) ] . Fluorouracil exhibited maximum teratogenicity when given to mice as single intraperitoneal injections of 10 to 40 mg/kg on day 10 or 12 of gestation. Similarly, intraperitoneal doses of 12 to 37 mg/kg given to rats between days 9 and 12 of gestation and intramuscular doses of 3 to 9 mg/kg given to hamsters between days 8 and 11 of gestation were teratogenic and/or embryotoxic (i.e., resulted in increased resorptions or embryolethality). In monkeys, divided doses of 40 mg/kg given between days 20 and 24 of gestation were not teratogenic. However, doses higher than 40 mg/kg resulted in spontaneous abortions. Based on the recommended human dose and instructions for use, it is not possible to calculate human dose equivalents for animal exposures in these studies.

Teratogenic Effects: Pregnancy Category X [see Contraindications (4.1) ] . Cases of miscarriage and birth defects (including cleft lip and cleft palate) have been reported when pregnant women were exposed to a topical or parenteral fluorouracil product. In addition, ventricular septal defect and cases of miscarriage occurred when pregnant women applied a topical fluorouracil product to mucous membranes (Tolak Cream is not indicated for use on the mucous membrane). Animal reproduction studies have not been conducted with Tolak Cream. Fluorouracil administered parenterally has been shown to be teratogenic in mice, rats, and hamsters when given at doses equivalent to the usual human intravenous dose. However, the amount of fluorouracil absorbed systemically after topical administration to actinic keratosis is minimal [see Clinical Pharmacology (12.3) ] . Fluorouracil exhibited maximum teratogenicity when given to mice as single intraperitoneal injections of 10 to 40 mg/kg on day 10 or 12 of gestation. Similarly, intraperitoneal doses of 12 to 37 mg/kg given to rats between days 9 and 12 of gestation and intramuscular doses of 3 to 9 mg/kg given to hamsters between days 8 and 11 of gestation were teratogenic and/or embryotoxic (i.e., resulted in increased resorptions or embryolethality). In monkeys, divided doses of 40 mg/kg given between days 20 and 24 of gestation were not teratogenic. However, doses higher than 40 mg/kg resulted in spontaneous abortions. Based on the recommended human dose and instructions for use, it is not possible to calculate human dose equivalents for animal exposures in these studies.

8.3 Nursing Mothers Because many drugs are excreted in human milk and there is some systemic absorption of fluorouracil after topical administration, and because of the potential for serious adverse reactions in nursing infants, a decision should be made whether to discontinue nursing or to discontinue drug use, taking into account the importance of the drug to the mother.

8.4 Pediatric Use Actinic keratosis is not usually observed in the pediatric population except in the case of rare genetic diseases. Tolak Cream is not intended for use in pediatric patients. Safety and effectiveness in children have not been established.

8.5 Geriatric Use No dose adjustment is required for elderly patients [see Clinical Studies (14) ] . The mean age of the 403 subjects treated with Tolak Cream in the clinical trials was 68 years. Of the Tolak Cream-treated subjects, 61% were 65 and over, while 28% were 75 and over. No overall differences in safety or effectiveness were observed between these subjects and younger subjects, and other reported clinical experience has not identified differences in responses between the elderly and younger patients, but greater sensitivity of some older individuals cannot be ruled out.

11 DESCRIPTION Tolak (fluorouracil) Cream, 4% contains 40 mg of fluorouracil per gram of white cream for topical application. It is a nucleoside metabolic inhibitor. Chemically, fluorouracil is 5-fluoro-2,4 (1H,3H)-pyrimidinedione. The molecular formula of 5-fluorouracil is C 4 H 3 FN 2 O 2 , and its molecular weight is 130.1. Its structural formula is: Tolak Cream contains the following inactive ingredients: arlacel-165, butylated hydroxytoluene, cetyl alcohol, anhydrous citric acid, glycerin, isopropyl myristate, methyl gluceth-10, methylparaben, propylparaben, purified water, peanut oil, sodium hydroxide, stearic acid, and stearyl alcohol. Tolak Cream formulation has an alkaline pH at 8.3 to 9.2. Chemical Structure

12 CLINICAL PHARMACOLOGY 12.1 Mechanism of Action There is evidence that the metabolism of fluorouracil in the anabolic pathway blocks the methylation reaction of deoxyuridylic acid to thymidylic acid. In this manner, fluorouracil interferes with the synthesis of DNA and to a lesser extent inhibits the formation of RNA. Since DNA and RNA are essential for cell division and growth, the effect of fluorouracil may be to create a thymine deficiency that provokes unbalanced growth and death of the cell. The effects of DNA and RNA deprivation are most marked on those cells that grow more rapidly and take up fluorouracil at a more rapid rate. 12.3 Pharmacokinetics A systemic absorption study of topically applied Tolak Cream was performed in 21 patients with at least 3 actinic keratosis lesions (4 mm or greater in diameter). The steady state concentration of 5-fluorouracil in plasma was examined at 1, 2, 4, 6, 8, 10, 12, 16, and 24 hours after the last dose of a 4-week regimen in subjects with actinic keratosis after "area application" to area(s) in which actinic keratosis lesions were identified at baseline. Areas were defined as the whole region of the left cheek, right cheek, chin and forehead, bald scalp, and right and left ears, where actinic keratosis was identified at baseline. Thus, for example, if an actinic keratosis lesion was identified on the left cheek, Tolak Cream was to be applied as a thin film to the whole area of the left cheek. Eight patients had undetectable levels of plasma 5-fluorouracil (the lower limit of quantification was 1.00 ng/ml) in all plasma samples following treatment with Tolak Cream. Among patients with detectable plasma 5-fluorouracil levels, the highest level of plasma 5-fluorouracil was generally observed at 1 hour post-dose. The mean observed maximum concentration (± standard deviation) of plasma 5-fluorouracil was 3.66 (±1.58) ng/mL with the range between 1.11 – 7.35 ng/mL. The catabolism of 5-fluorouracil results in inactive degradation products (such as CO 2 , urea, α-fluoro-β-alanine).

12.1 Mechanism of Action There is evidence that the metabolism of fluorouracil in the anabolic pathway blocks the methylation reaction of deoxyuridylic acid to thymidylic acid. In this manner, fluorouracil interferes with the synthesis of DNA and to a lesser extent inhibits the formation of RNA. Since DNA and RNA are essential for cell division and growth, the effect of fluorouracil may be to create a thymine deficiency that provokes unbalanced growth and death of the cell. The effects of DNA and RNA deprivation are most marked on those cells that grow more rapidly and take up fluorouracil at a more rapid rate.

12.3 Pharmacokinetics A systemic absorption study of topically applied Tolak Cream was performed in 21 patients with at least 3 actinic keratosis lesions (4 mm or greater in diameter). The steady state concentration of 5-fluorouracil in plasma was examined at 1, 2, 4, 6, 8, 10, 12, 16, and 24 hours after the last dose of a 4-week regimen in subjects with actinic keratosis after "area application" to area(s) in which actinic keratosis lesions were identified at baseline. Areas were defined as the whole region of the left cheek, right cheek, chin and forehead, bald scalp, and right and left ears, where actinic keratosis was identified at baseline. Thus, for example, if an actinic keratosis lesion was identified on the left cheek, Tolak Cream was to be applied as a thin film to the whole area of the left cheek. Eight patients had undetectable levels of plasma 5-fluorouracil (the lower limit of quantification was 1.00 ng/ml) in all plasma samples following treatment with Tolak Cream. Among patients with detectable plasma 5-fluorouracil levels, the highest level of plasma 5-fluorouracil was generally observed at 1 hour post-dose. The mean observed maximum concentration (± standard deviation) of plasma 5-fluorouracil was 3.66 (±1.58) ng/mL with the range between 1.11 – 7.35 ng/mL. The catabolism of 5-fluorouracil results in inactive degradation products (such as CO 2 , urea, α-fluoro-β-alanine).

13 NONCLINICAL TOXICOLOGY 13.1 Carcinogenesis, Mutagenesis, Impairment of Fertility Adequate long-term studies in animals to evaluate carcinogenic potential of fluorouracil have not been conducted. Studies with the active ingredient of Tolak, fluorouracil, have shown mutagenic effects in in vitro and in vivo tests and impairment of fertility in in vivo animal studies. Fluorouracil was positive in three in vitro cell neoplastic transformation assays. In the C3H/10T½ clone 8 mouse embryo cell system, the resulting morphologically transformed cells formed tumors when inoculated into immunosuppressed syngeneic mice. Although no evidence for mutagenic activity of fluorouracil was observed in 3 studies utilizing the Ames test, mutagenic activity was observed in the survival count rec-assay with Bacillus subtilis and in the Drosophila wing-hair spot test. Fluorouracil produced petite mutations in Saccharomyces cerevisiae and demonstrated positive results in the micronucleus test using bone marrow cells of male mice. Fluorouracil demonstrated clastogenic activity in vitro in Chinese hamster fibroblasts at concentrations of 1.0 and 2.0 µg/mL and was associated with chromatid gaps, breaks, and exchanges. In human lymphocytes, fluorouracil increased sister chromatid exchange in vitro. Additionally, an increase in numerical and structural chromosome aberrations have been observed in peripheral lymphocytes of patients treated with 5-fluorouracil. In rats, chromosomal abnormalities and changes in chromosome organization in spermatogonia have been observed after intraperitoneal administration of 125 to 250 mg/kg of fluorouracil. Spermatogonial differentiation was also inhibited and resulted in transient infertility. Fluorouracil was inactive, however, at oral doses of 5 to 80 mg/kg/day in studies with a strain of mouse which is sensitive to the induction of sperm head abnormalities after exposure to a range of chemical mutagens and carcinogens. In female rats, fluorouracil administered intraperitoneally at doses of 25 and 50 mg/kg during the preovulatory phase of oogenesis resulted in a significant reduction in the incidence of fertile matings, a delay in the development of preimplantation and postimplantation embryos, an increased incidence of preimplantation lethality, and an induction of chromosomal anomalies in these embryos. In mice, single intravenous or intraperitoneal injections of fluorouracil were toxic to differentiated spermatogonia and spermatocytes (at 500 mg/kg) and produced abnormalities in spermatids (at 50 mg/kg).

13.1 Carcinogenesis, Mutagenesis, Impairment of Fertility Adequate long-term studies in animals to evaluate carcinogenic potential of fluorouracil have not been conducted. Studies with the active ingredient of Tolak, fluorouracil, have shown mutagenic effects in in vitro and in vivo tests and impairment of fertility in in vivo animal studies. Fluorouracil was positive in three in vitro cell neoplastic transformation assays. In the C3H/10T½ clone 8 mouse embryo cell system, the resulting morphologically transformed cells formed tumors when inoculated into immunosuppressed syngeneic mice. Although no evidence for mutagenic activity of fluorouracil was observed in 3 studies utilizing the Ames test, mutagenic activity was observed in the survival count rec-assay with Bacillus subtilis and in the Drosophila wing-hair spot test. Fluorouracil produced petite mutations in Saccharomyces cerevisiae and demonstrated positive results in the micronucleus test using bone marrow cells of male mice. Fluorouracil demonstrated clastogenic activity in vitro in Chinese hamster fibroblasts at concentrations of 1.0 and 2.0 µg/mL and was associated with chromatid gaps, breaks, and exchanges. In human lymphocytes, fluorouracil increased sister chromatid exchange in vitro. Additionally, an increase in numerical and structural chromosome aberrations have been observed in peripheral lymphocytes of patients treated with 5-fluorouracil. In rats, chromosomal abnormalities and changes in chromosome organization in spermatogonia have been observed after intraperitoneal administration of 125 to 250 mg/kg of fluorouracil. Spermatogonial differentiation was also inhibited and resulted in transient infertility. Fluorouracil was inactive, however, at oral doses of 5 to 80 mg/kg/day in studies with a strain of mouse which is sensitive to the induction of sperm head abnormalities after exposure to a range of chemical mutagens and carcinogens. In female rats, fluorouracil administered intraperitoneally at doses of 25 and 50 mg/kg during the preovulatory phase of oogenesis resulted in a significant reduction in the incidence of fertile matings, a delay in the development of preimplantation and postimplantation embryos, an increased incidence of preimplantation lethality, and an induction of chromosomal anomalies in these embryos. In mice, single intravenous or intraperitoneal injections of fluorouracil were toxic to differentiated spermatogonia and spermatocytes (at 500 mg/kg) and produced abnormalities in spermatids (at 50 mg/kg).

14 CLINICAL STUDIES The efficacy and safety of Tolak Cream was evaluated in two double-blind multi-center trials (Trial 1 and Trial 2) in subjects with at least 5 visible actinic keratosis lesions on the face, scalp, and/or ears. Subjects applied the assigned medication (Tolak Cream or vehicle placebo) to the face, and/or ears and/or scalp once or twice daily for four weeks as directed. Application of the medication involved field treatment of the whole area of the face and/or ears and/or scalp where actinic keratosis lesions were identified at baseline. Subjects receiving confounding treatments or medications were excluded. The effect of treatment was assessed at 4 weeks post-treatment. Subjects were almost all Caucasian, the mean age was approximately 68 years (range was from 33 to 89 years), and the mean number of actinic keratosis lesions was 14.4 in the Tolak group and 16.2 in the vehicle group in Trial 1, and 19.2 in the Tolak group and 23.2 in the vehicle group in Trial 2. The number and percentage of subjects with 100% clearing of their actinic keratosis lesions and with at least 75% clearing of their actinic keratosis lesions are shown in Table 2. Table 2 Subjects with 100% and at least 75% Clearing of Actinic Keratosis Lesions at 4 Weeks Post-Treatment Tolak Cream % (n/N) Vehicle % (n/N) Subjects with 100% Clearing of Actinic Keratosis Lesions Trial 1 54% (192/353) 4% (3/70) Trial 2 24% (12/50) 4% (2/50) Subjects with At Least 75% Clearing of Actinic Keratosis Lesions Trial 1 80% (284/353) 7% (5/70) Trial 2 74% (37/50) 10% (5/50) Examination of age (< 68 years versus ≥ 68 years) and gender subgroups did not identify differences in response to Tolak Cream among these subgroups. There were too few non-Caucasian subjects to adequately assess differences in effects among racial subgroups. After completing Trials 1 and 2, subjects who achieved 100% clearing of actinic keratosis lesions with Tolak Cream treatment were followed for 12 months for lesion recurrence. Table 3 presents the long term outcomes of these 204 subjects. Table 3 Recurrence of Actinic Keratosis Lesions within 12 Months After Completing Trial 1 or 2 Cleared Tolak Subjects N=204 Subjects remained clear 12 months after treatment 56 (27%) Subjects with recurrence within 12 months Subjects who applied other treatments for actinic keratosis were counted as having recurrence. 110 (54%) Subjects with no follow-up 38 (19%)

<table width="85%"><caption>Table 2 Subjects with 100% and at least 75% Clearing of Actinic Keratosis Lesions at 4 Weeks Post-Treatment </caption><col width="20%" align="left" valign="top"/><col width="40%" align="center" valign="top"/><col width="40%" align="center" valign="top"/><thead><tr><th styleCode="Lrule"/><th>Tolak Cream % (n/N)</th><th styleCode="Rrule">Vehicle % (n/N)</th></tr></thead><tbody><tr><td align="center" valign="top" colspan="3" styleCode="Lrule Rrule">Subjects with 100% Clearing of Actinic Keratosis Lesions </td></tr><tr><td styleCode="Lrule">Trial 1</td><td>54% (192/353) </td><td styleCode="Rrule">4% (3/70) </td></tr><tr><td styleCode="Lrule">Trial 2</td><td>24% (12/50) </td><td styleCode="Rrule">4% (2/50) </td></tr><tr><td align="center" valign="top" colspan="3" styleCode="Lrule Rrule">Subjects with At Least 75% Clearing of Actinic Keratosis Lesions </td></tr><tr><td styleCode="Lrule">Trial 1</td><td>80% (284/353) </td><td styleCode="Rrule">7% (5/70) </td></tr><tr><td styleCode="Lrule">Trial 2</td><td>74% (37/50) </td><td styleCode="Rrule">10% (5/50) </td></tr></tbody></table> <table width="85%"><caption>Table 3 Recurrence of Actinic Keratosis Lesions within 12 Months After Completing Trial 1 or 2</caption><col width="70%" align="left" valign="top"/><col width="30%" align="center" valign="top"/><thead><tr><th styleCode="Lrule Rrule"/><th styleCode="Rrule">Cleared Tolak Subjects N=204</th></tr></thead><tbody><tr styleCode="Botrule"><td styleCode="Lrule Rrule">Subjects remained clear 12 months after treatment</td><td styleCode="Rrule">56 (27%)</td></tr><tr styleCode="Botrule"><td styleCode="Lrule Rrule">Subjects with recurrence within 12 months<footnote>Subjects who applied other treatments for actinic keratosis were counted as having recurrence.</footnote></td><td styleCode="Rrule">110 (54%)</td></tr><tr><td styleCode="Lrule Rrule">Subjects with no follow-up</td><td styleCode="Rrule">38 (19%)</td></tr></tbody></table>

16 HOW SUPPLIED / STORAGE AND HANDLING 16.1 How Supplied Tolak (fluorouracil) Cream, 4% containing 40 mg of fluorouracil per gram of white cream is available in a 40 gram tube (NDC 28105-421-40). 16.2 Storage and Handling Store at 25°C (77°F), with excursion permitted from 15°C to 30°C (59°F - 86°F) [See USP Controlled Room Temperature]. Do not freeze. 16.1 How Supplied Tolak (fluorouracil) Cream, 4% containing 40 mg of fluorouracil per gram of white cream is available in a 40 gram tube (NDC 28105-421-40).

17 PATIENT COUNSELING INFORMATION Advise the patient to read the FDA-approved patient labeling (Patient Information). Important Administration Instructions Advise patients of the following: Tolak Cream is for external use only. Do not apply to eyes, nose, mouth or mucous membranes. Avoid inadvertent transfer of Tolak Cream to other body areas, or to another person. Keep out of the reach of children. Fluorouracil, including Tolak may be fatal if ingested by pets. Avoid allowing pets to contact the Tolak container or the skin where Tolak has been applied. Store Tolak out of reach of pets. Safely discard or clean any cloth or applicator that may retain Tolak and avoid leaving any residues of Tolak on your hands, clothing, carpeting or furniture. Instruct patients to do the following: Apply after washing, rinsing, and drying the treatment area. Wash hands thoroughly after application. Hypersensitivity Reactions Inform patients that Tolak Cream contains peanut oil and that hypersensitivity reactions may occur with its use. Inform patients to discontinue Tolak Cream immediately and seek medical attention if signs of severe hypersensitivity occur [see Warnings and Precautions (5.2) ] . Ophthalmic Adverse Reactions Inform patients that ophthalmic adverse reactions can occur with Tolak Cream use. Advise patients that Tolak Cream is not for ophthalmic use. Advise patients to avoid application around the eyes. If accidental exposure occurs, advise patients to flush eye(s) with large amounts of water and seek medical care [see Warnings and Precautions (5.3) ] . Increased Sensitivity to UV Light Inform patients that topical fluorouracil is associated with photosensitivity reactions including severe sunburn. Advise patients to minimize exposure to sun, sun lamps, and tanning beds while using Tolak Cream. Advise patients that sunscreens may be applied after Tolak Cream application [see Warnings and Precautions (5.4) ] . Embryofetal Toxicity Inform females of reproductive potential of the potential risk to a fetus. Advise females of reproductive potential to use effective contraception during and for one month after the last dose of Tolak Cream and to inform their healthcare provider of a known or suspected pregnancy [see Warnings and Precautions (5.5) ]. Systemic Toxicity in Patients with DPD deficiency Advise patient to stop using Tolak immediately and contact physician if abdominal (stomach) pain, bloody diarrhea, vomiting, fever, and/or chills occur with Tolak Cream use. Inform patient that these symptoms could be manifestations of a deficiency in the enzyme dihydropyrimidine dehydrogenase (DPD) [see Warnings and Precautions (5.6) ] .

PATIENT INFORMATION Tolak (tol lak) (fluorouracil) Cream, 4% Important : Tolak Cream is for use on skin only (topical). Do not get or apply Tolak Cream on your eyelids or in your eyes, nose, mouth, or in the vagina, because it may cause irritation and swelling in these areas. What is Tolak Cream? Tolak Cream is a prescription medicine used to treat skin lesions called actinic keratosis on the face, ears, or scalp. It is not known if Tolak Cream is safe and effective for use on other areas of the body or to treat problems other than actinic keratosis. It is not known if Tolak Cream is safe and effective in children. Who should not use Tolak Cream? Do not use Tolak Cream if: you are pregnant or may become pregnant. Tolak Cream may harm your unborn child. Stop using Tolak Cream and tell your doctor right away if you become pregnant while using Tolak Cream. your body does not make enough of (you are deficient in) the enzyme called dihydropyrimidine dehydrogenase (DPD). If you do not have enough of this enzyme, you may get serious side effects if you use Tolak Cream. Symptoms of serious side effects include: stomach-area abdominal pain, bloody diarrhea, vomiting, fever, and chills. What should I tell my doctor before using Tolak Cream? Before using Tolak Cream, tell your doctor about all your medical conditions, including if you: are allergic to any of the ingredients in Tolak Cream. Tolak Cream contains peanut oil . See the end of this leaflet for a list of all of the ingredients in Tolak Cream. are pregnant or plan to become pregnant. See " Who should not use Tolak Cream? " Females who are able to become pregnant should use an effective method of birth control during treatment with Tolak Cream and for one month after the last dose of Tolak Cream. Talk to your doctor about birth control methods that may be right for you during treatment with Tolak Cream. are breastfeeding or plan to breastfeed. It is not known if Tolak Cream passes into your breast milk. You and your doctor should decide if you will use Tolak Cream or breastfeed. How should I use Tolak Cream? Use Tolak Cream exactly as prescribed by your doctor. Apply Tolak Cream 1 time each day, to the areas of your skin to be treated, for 4 weeks. Apply Tolak Cream as follows: Gently wash, rinse, and pat dry the skin areas to be treated. Apply a thin film of the Tolak Cream to the areas to be treated. Gently massage Tolak Cream evenly into your skin. Avoid contact with other areas of your body, and transfer of Tolak Cream from your body to other people. Wash your hands well after you apply Tolak Cream. What should I avoid while using Tolak Cream? Do not cover the treated areas with an airtight dressing. • Avoid sunlight. Tolak Cream can make your skin sensitive to the sun. You could get severe sunburn. Limit your time in the sun during treatment with Tolak Cream. Talk to your doctor if you get sunburn. Do not breast feed or become pregnant while using Tolak. If you do become pregnant, stop using Tolak and tell your doctor right away. Tolak may be fatal to your pet if your pet licks or ingests Tolak. Avoid allowing pets to contact the Tolak container or your skin where you applied Tolak. Store Tolak out of reach of pets. Safely discard or clean any cloth or applicator that may have Tolak residue. Avoid applying Tolak on your clothing, carpeting, or furniture.

be fatal to your pet if your pet licks or ingests Tolak. Avoid allowing pets to contact the Tolak container or your skin where you applied Tolak. Store Tolak out of reach of pets. Safely discard or clean any cloth or applicator that may have Tolak residue. Avoid applying Tolak on your clothing, carpeting, or furniture. If your pet starts vomiting or starts having a seizure after your pet licks or ingests Tolak, seek immediate veterinary care for your pet. What are the possible side effects of Tolak Cream? Tolak Cream can cause serious side effects: Skin reactions including possible allergic reactions. Most people using Tolak Cream get skin reactions in the treated areas. You may get skin reactions such as: redness dryness or scaling crusting itching stinging or burning swelling skin loss (erosion) Eye problems . Eye problems have happened with the use of medicines that contain fluorouracil that are applied to the skin. To help prevent getting Tolak Cream in your eyes, or transferring Tolak Cream from another part of your body to your eyes or to another person's eyes: avoid applying Tolak Cream near or around your eyes wash your hands well after you apply Tolak Cream If you accidentally get Tolak Cream in your eyes, or if Tolak Cream is accidentally transferred to another person's eyes, flush eyes with large amounts of water and get medical help as soon as possible. Tolak Cream can cause serious side effects in people who do not have enough of the enzyme dihydropyrimidine dehydrogenase (DPD) . See " Who should not use Tolak Cream? " and " What should I tell my doctor before using Tolak Cream? " Stop using Tolak Cream and call your doctor right away if you get any of the following symptoms during treatment with Tolak Cream: stomach-area (abdominal) pain bloody diarrhea vomiting fever chills Tell your doctor if you get any of these skin reactions and they are severe or do not go away. These are not all the possible side effects of Tolak Cream. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088. How should I store Tolak Cream? Store Tolak Cream between 68°F to 77°F (20°C to 25°C). Do not freeze Tolak Cream. Do not use Tolak Cream after the expiration date printed on the tube. Keep Tolak Cream and all medicines out of the reach of children. General information about the safe and effective use of Tolak Cream Medicines are sometimes prescribed for purposes other than those listed in a Patient Information leaflet. Do not use Tolak Cream for a condition for which it was not prescribed. Do not give Tolak Cream to other people, even if they have the same symptoms that you have. It may harm them. You can ask your pharmacist or doctor for information about Tolak Cream that is written for health professionals. What are the ingredients in Tolak Cream? Active ingredient: fluorouracil Inactive ingredients: arlacel-165, butylated hydroxytoluene, cetyl alcohol, anhydrous citric acid, glycerin, isopropyl myristate, methyl gluceth-10, methylparaben, propylparaben, purified water, peanut oil, sodium hydroxide, stearic acid, and stearyl alcohol. Manufactured and Distributed by: Hill Dermaceuticals, Inc. Sanford, Florida 32773 For more information, go to www.hillderm.com or call 1-800-344-5707. This Patient Information has been approved by the U.S. Food and Drug Administration. Issued: August 2022

<table width="65%" styleCode="Noautorules"><col width="50%" align="left" valign="top"/><col width="50%" align="left" valign="top"/><tbody><tr><td><list listType="unordered" styleCode="circle"><item>redness </item><item>dryness or scaling </item><item>crusting</item><item>itching</item></list></td><td><list listType="unordered" styleCode="circle"><item>stinging or burning</item><item>swelling</item><item>skin loss (erosion)</item></list></td></tr></tbody></table> <table width="75%" styleCode="Noautorules"><col width="60%" align="left" valign="top"/><col width="20%" align="left" valign="top"/><col width="20%" align="left" valign="top"/><tbody><tr><td><list listType="unordered" styleCode="circle"><item>stomach-area (abdominal) pain </item><item>bloody diarrhea </item></list></td><td><list listType="unordered" styleCode="circle"><item>vomiting </item><item>fever </item></list></td><td><list listType="unordered" styleCode="circle"><item>chills</item></list></td></tr></tbody></table>

WARNING: SERIOUS ADVERSE REACTIONS OR DEATH IN PATIENTS WITH COMPLETE DPD DEFICIENCY Increased Risk of Serious Adverse Reactions or Death in Patients with Complete DPD Deficiency Test patients for genetic variants of DPYD prior to initiating fluorouracil unless immediate treatment is necessary. Avoid use of fluorouracil in patients with certain homozygous or compound heterozygous DPYD variants that result in complete DPD deficiency [see Warnings and Precautions ( 5.1 )] WARNING: SERIOUS ADVERSE REACTIONS OR DEATH IN PATIENTS WITH COMPLETE DPD DEFICIENCY See full prescribing information for complete boxed warning. Serious adverse reactions or death may occur in patients with complete DPD deficiency. Test patients for genetic variants of DPYD prior to initiating fluorouracil unless immediate treatment is necessary. Avoid use of fluorouracil in patients with certain homozygous or compound heterozygous DPYD variants that result in complete DPD deficiency. ( 2.1 , 5.1 )

1 INDICATIONS & USAGE Fluorouracil is indicated for the treatment of patients with: Fluorouracil is a nucleoside metabolic inhibitor indicated for the treatment of patients with •Adenocarcinoma of the Colon and Rectum ( 1.1 ) •Adenocarcinoma of the Breast ( 1.2 ) •Gastric Adenocarcinoma ( 1.3 ) •Pancreatic Adenocarcinoma ( 1.4 ) 1.1 Adenocarcinoma of the Colon and Rectum 1.2 Adenocarcinoma of the Breast 1.3 Gastric Adenocarcinoma 1.4 Pancreatic Adenocarcinoma 1.1 Adenocarcinoma of the Colon and Rectum 1.2 Adenocarcinoma of the Breast 1.3 Gastric Adenocarcinoma 1.4 Pancreatic Adenocarcinoma

2 DOSAGE & ADMINISTRATION •Fluorouracil is recommended for administration either as an intravenous bolus or as an intravenous infusion. ( 2.2 ) •See Full Prescribing Information for dose individualization ( 2.2 ) and dose modifications due to adverse reactions ( 2.7 ) •See Full Prescribing Information for recommended doses of fluorouracil for adenocarcinoma of the colon and rectum ( 2.3 ) and for recommended doses of fluorouracil as a component of a chemotherapy regimen for adenocarcinoma of the breast ( 2.4 ), gastric adenocarcinoma ( 2.5 ), pancreatic adenocarcinoma ( 2.6 ) 2.1 Evaluation and Testing for DPD Deficiency Before Initiating fluorouracil Prior to initiating fluorouracil, test patients for genetic variants of the DPYD gene unless immediate treatment is necessary. An FDA authorized test for the detection of the DPYD gene to identify patients at risk of serious adverse reactions with fluorouracil is not currently available. Currently available tests used to identify DPYD variants may vary in accuracy and design (e.g., which DPYD variant(s) they identify). Avoid use of fluorouracil in patients known to have certain homozygous or compound heterozygous DPYD variants that result in complete DPD deficiency. No fluorouracil dose has been proven safe for patients with complete DPD deficiency. For patients with partial DPD deficiency, individualize the dosage and modify based on tolerability and intent of treatment [see Warnings and Precautions ( 5.1 )]. 2.2 General Dosage Information Fluorouracil is recommended for administration either as an intravenous bolus or as an intravenous infusion. Do not inject the entire contents of the vial directly into patients. Individualize the dose and dosing schedule of fluorouracil based on tumor type, the specific regimen administered, disease state, response to treatment, and patient risk factors. 2.3 Recommended Dosage for Adenocarcinoma of the Colon and Rectum • The recommended dose of fluorouracil, administered in an infusional regimen in combination with leucovorin alone, or in combination with leucovorin and oxaliplatin or irinotecan, is 400 mg/m2 by intravenous bolus on Day 1, followed by 2400 mg/m2 to 3000 mg/m2 intravenously as a continuous infusion over 46 hours every two weeks. • The recommended dose of fluorouracil, if administered in a bolus dosing regimen in combination with leucovorin, is 500 mg/m2 by intravenous bolus on Days 1, 8, 15, 22, 29, and 36 in 8-week cycles. 2.4 Recommended Dosage for Adenocarcinoma of the Breast The recommended dose of fluorouracil, administered as a component of a cyclophosphamide based multidrug regimen, is 500 mg/m2 or 600 mg/m2 intravenously on Days 1 and 8 every 28 days for 6 cycles 2.5 Recommended Dosage for Gastric Adenocarcinoma • The recommended dose of fluorouracil, administered as a component of a platinum-containing multidrug chemotherapy regimen, is 200 mg/m2 to 1000 mg/m2 intravenously as a continuous infusion over 24 hours. The frequency of dosing in each cycle and the length of each cycle will depend on the dose of fluorouracil and the specific regimen administered. 2.6 Recommended Dosage for Pancreatic Adenocarcinoma • The recommended dose of fluorouracil, administered as an infusional regimen in combination with leucovorin or as a component of a multidrug chemotherapy regimen that includes leucovorin, is 400 mg/m2 intravenous bolus on Day 1, followed by 2400 mg/m2 intravenously as a continuous infusion over 46 hours every two weeks.

The recommended dose of fluorouracil, administered as an infusional regimen in combination with leucovorin or as a component of a multidrug chemotherapy regimen that includes leucovorin, is 400 mg/m2 intravenous bolus on Day 1, followed by 2400 mg/m2 intravenously as a continuous infusion over 46 hours every two weeks. 2.7 Dose Modifications Withhold fluorouracil for any of the following: • Development of angina, myocardial infarction/ischemia, arrhythmia, or heart failure in patients with no history of coronary artery disease or myocardial dysfunction [see Warnings and Precautions ( 5.2 )] • Hyperammonemic encephalopathy [see Warnings and Precautions ( 5.3 )] • Acute cerebellar syndrome, confusion, disorientation, ataxia, or visual disturbances [see Warnings and Precautions ( 5.4 )] • Grade 3 or 4 diarrhea [see Warnings and Precautions ( 5.5 )] • Grade 2 or 3 palmar-plantar erythrodysesthesia (hand-foot syndrome) [see Warnings and Precautions ( 5.6 )] • Grade 3 or 4 mucositis [see Warnings and Precautions ( 5.8 )] • Grade 4 myelosuppression [see Warnings and Precautions ( 5.7 )] Upon resolution or improvement to Grade 1 diarrhea, mucositis, myelosuppression, or palmarplantar erythrodysesthesia, resume fluorouracil administration at a reduced dose. There is no recommended dose for resumption of fluorouracil administration following development of any of the following adverse reactions: • Cardiac toxicity • Hyperammonemic encephalopathy • Acute cerebellar syndrome, confusion, disorientation, ataxia, or visual disturbances 2.8 Preparation for Administration Fluorouracil is supplied in a single dose vial. The 10 mL/20 mL vial is only intended for preparation in a Pharmacy Admixture Service under appropriate conditions for cytotoxic drugs [see References ( 15 )]. Store vial at room temperature. Using aseptic conditions, penetrate the container closure once with a suitable sterile transfer device or dispensing set that allows measured distribution of the contents. Withdraw the calculated dose for an individual patient into a sterile syringe. Inspect the solution in syringe for particulate matter and discoloration prior to administration or further dilution. Discard syringe if the solution is discolored or contains particulate matter. 2.9 Administration Do not administer in the same intravenous line concomitantly with other medicinal products. For bolus administration, store undiluted fluorouracil in the syringe for up to 4 hours at room temperature (25°C). Administer fluorouracil as an intravenous bolus through an established intravenous line. Store diluted solutions of fluorouracil for up to 4 hours at room temperature (25°C) prior to administration to the patient. For intravenous infusion regimens, administer through a central venous line using an infusion pump.

3 DOSAGE FORMS & STRENGTHS Fluorouracil injection USP is supplied as single dose vial containing 500 mg/10 mL (50 mg/mL) and 1 g/20 mL (50 mg/mL) fluorouracil. Injection: 500 mg in a 10 mL vial in Single dose vial ( 3 ) 1 g in a 20 mL vial in Single dose vial ( 3 )

5 WARNINGS AND PRECAUTIONS • Cardiotoxicity: Fluorouracil can cause cardiotoxicity, including angina, myocardial infarction/ischemia, arrhythmia, and heart failure. Withhold fluorouracil for cardiac toxicity. ( 5.2 ) • Hyperammonemic Encephalopathy: Altered mental status, confusion, disorientation, coma, or ataxia with elevated serum ammonia level can occur within 72 hours of initiation of fluorouracil. Withhold fluorouracil and initiate ammonia-lowering therapy. ( 5.3 ) • Neurologic Toxicity: Fluorouracil can cause acute cerebellar syndrome, confusion, disorientation, ataxia, or visual disturbances. Withhold fluorouracil for neurologic toxicity. ( 5.4 ) • Diarrhea: Fluorouracil can cause severe diarrhea. Withhold fluorouracil for severe diarrhea until resolved. ( 5.5 ) • Palmar-Plantar Erythrodysesthesia (Hand-Foot Syndrome): Fluorouracil can cause hand-foot syndrome. If severe, discontinue fluorouracil until resolved or decreased to Grade 1, then resume at a reduced dose. ( 5.6 ) • Myelosuppression: Fluorouracil can cause severe and fatal myelosuppression. Withhold fluorouracil until severe myelosuppression resolves, then resume at a reduced dose. ( 5.7 ) • Mucositis: Fluorouracil can cause severe mucositis. Discontinue fluorouracil until resolved or decreased to Grade 1, then resume at a reduced dose. ( 5.8 ) • Increased Risk of Elevated INR with Warfarin: Concurrent administration with warfarin can result in clinically significant increases in coagulation parameters: Closely monitor INR and prothrombin time. ( 5.9 ) • Embryofetal Toxicity: Fluorouracil can cause fetal harm. Advise females and males of reproductive potential of the potential risk to a fetus. ( 5.10 , 8.1 , 8.6 ) 5.1 Serious Adverse Reactions or Death from Dihydropyrimidine Dehydrogenase (DPD) Deficiency Patients with certain homozygous or compound heterozygous variants in the DPYD gene known to result in complete or near complete absence of DPD activity (complete DPD deficiency) are at increased risk for acute early-onset toxicity and serious, including fatal, adverse reactions due to fluorouracil (e.g., mucositis, diarrhea, neutropenia, and neurotoxicity). Patients with partial DPD activity (partial DPD deficiency) may also have increased risk of serious, or fatal, adverse reactions. Prior to initiating fluorouracil, test patients for genetic variants of the DPYD gene unless immediate treatment is necessary [see Clinical Pharmacology ( 12.5 )]. Serious adverse reactions may still occur even if no DPYD variants are identified. Avoid use of fluorouracil in patients with certain homozygous or compound heterozygous DPYD variants that result in complete DPD deficiency. Withhold or permanently discontinue fluorouracil based on clinical assessment of the onset, duration, and severity of adverse reactions in patients with evidence of acute early-onset or unusually severe reactions. No fluorouracil dose has been proven safe for patients with complete DPD deficiency. For patients with partial DPD deficiency, individualize the dosage and modify based on tolerability and intent of treatment. An FDA-authorized test for the detection of genetic variants of the DPYD gene to identify patients at risk of serious adverse reactions with fluorouracil treatment is not currently available. Currently available tests used to identify DPYD variants may vary in accuracy and design (e.g., which DPYD variant(s) they identify).

A-authorized test for the detection of genetic variants of the DPYD gene to identify patients at risk of serious adverse reactions with fluorouracil treatment is not currently available. Currently available tests used to identify DPYD variants may vary in accuracy and design (e.g., which DPYD variant(s) they identify). 5.2 Cardiotoxicity Fluorouracil can cause cardiotoxicity, including angina, myocardial infarction/ischemia, arrhythmia, and heart failure, based on postmarketing reports. Reported risk factors for cardiotoxicity are administration by continuous infusion rather than intravenous bolus and presence of coronary artery disease. Withhold fluorouracil for cardiotoxicity. The risks of resumption of fluorouracil in patients with cardiotoxicity that has resolved have not been established. 5.3 Hyperammonemic Encephalopathy Fluorouracil can cause hyperammonemic encephalopathy in the absence of liver disease or other identifiable cause, based on postmarketing reports. Signs or symptoms of hyperammonemic encephalopathy began within 72 hours after initiation of fluorouracil infusion; these included altered mental status, confusion, disorientation, coma, or ataxia, in the presence of concomitant elevated serum ammonia level. Withhold fluorouracil for hyperammonemic encephalopathy and initiate ammonia-lowering therapy. The risks of resumption of fluorouracil in patients with hyperammonemic encephalopathy that has resolved have not been established. 5.4 Neurologic Toxicity Fluorouracil can cause neurologic toxicity, including acute cerebellar syndrome and other neurologic events, based on postmarketing reports. Neurologic symptoms included confusion, disorientation, ataxia, or visual disturbances. Withhold fluorouracil for neurologic toxicity. There are insufficient data on the risks of resumption of fluorouracil in patients with neurologic toxicity that has resolved. 5.5 Diarrhea Fluorouracil can cause severe diarrhea. Withhold fluorouracil for Grade 3 or 4 diarrhea until resolved or decreased in intensity to Grade 1, then resume fluorouracil at a reduced dose. Administer fluids, electrolyte replacement, or antidiarrheal treatments as necessary. 5.6 Palmar-Plantar Erythrodysesthesia (Hand-Foot Syndrome) Fluorouracil can cause palmar-plantar erythrodysesthesia, also known as hand-foot syndrome (HFS). Symptoms of HFS include a tingling sensation, pain, swelling, and erythema with tenderness, and desquamation. HFS occurs more commonly when fluorouracil is administered as a continuous infusion than when fluorouracil is administered as a bolus injection, and has been reported to occur more frequently in patients with previous exposure to chemotherapy. HFS is generally observed after 8-9 weeks of fluorouracil administration but may occur earlier. Institute supportive measures for symptomatic relief of HFS. Withhold fluorouracil administration for Grade 2 or 3 HFS; resume fluorouracil at a reduced dose when HFS is completely resolved or decreased in severity to Grade 1. 5.7 Myelosuppression Fluorouracil can cause severe and fatal myelosuppression which may include neutropenia, thrombocytopenia, and anemia. The nadir in neutrophil counts commonly occurs between 9 and 14 days after fluorouracil administration. Obtain complete blood counts prior to each treatment cycle, weekly if administered on a weekly or similar schedule, and as needed. Withhold fluorouracil until Grade 4 myelosuppression resolves; resume fluorouracil at a reduced dose when myelosuppression has resolved or improved to Grade 1 in severity. 5.8 Mucositis Mucositis, stomatitis or esophagopharyngitis, which may lead to mucosal sloughing or ulceration, can occur with fluorouracil.

needed. Withhold fluorouracil until Grade 4 myelosuppression resolves; resume fluorouracil at a reduced dose when myelosuppression has resolved or improved to Grade 1 in severity. 5.8 Mucositis Mucositis, stomatitis or esophagopharyngitis, which may lead to mucosal sloughing or ulceration, can occur with fluorouracil. The incidence is reported to be higher with administration of fluorouracil by intravenous bolus compared with administration by continuous infusion. Withhold fluorouracil administration for Grade 3 or 4 mucositis; resume fluorouracil at a reduced dose once mucositis has resolved or decreased in severity to Grade 1. 5.9 Increased Risk of Elevated International Normalized Ratio (INR) with Warfarin Clinically significant elevations in coagulation parameters have been reported during concomitant use of warfarin and fluorouracil. Closely monitor patients receiving concomitant coumarin-derivative anticoagulants such as warfarin for INR or prothrombin time in order to adjust the anticoagulant dose accordingly [see Drug Interactions ( 7 )]. 5.10 Embryofetal Toxicity Based on its mechanism of action, fluorouracil can cause fetal harm when administered to a pregnant woman. In animal studies, administration of fluorouracil at doses lower than a human dose of 12 mg/kg caused teratogenicity. If this drug is used during pregnancy, or if the patient becomes pregnant while taking this drug, the patient should be apprised of the potential hazard to a fetus. Advise females of reproductive potential and males with female partners of reproductive potential to use effective contraception during and for 3 months following cessation of therapy with fluorouracil [see Use in Specific Populations ( 8.1 , 8.6 ), Clinical Pharmacology ( 12.1 ), and Nonclinical Toxicology ( 13.1 )].

6 ADVERSE REACTIONS The following adverse reactions are discussed in more detail in other sections of the labeling: • Serious Adverse Reactions or Death from Dihydropyrimidine Dehydrogenase (DPD) Deficiency [see Warnings and Precautions ( 5.1 )] •Cardiotoxicity [see Warnings and Precautions ( 5.2 )] •Hyperammonemic Encephalopathy [see Warnings and Precautions ( 5.3 )] •Neurologic Toxicity [see Warnings and Precautions ( 5.4 )] •Diarrhea [see Warnings and Precautions ( 5.5 )] •Palmar-Plantar Erythrodysesthesia (Hand-Foot Syndrome) [see Warnings and Precautions ( 5.6 )] •Myelosuppression [see Warnings and Precautions ( 5.7 ) ] •Mucositis [see Warnings and Precautions ( 5.8 )] •Increased risk of elevated INR when administrated with warfarin [see Warnings and Precautions ( 5.9 )] To report SUSPECTED ADVERSE REACTIONS, contact BluePoint Laboratories at 1-800-707-4621 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch 6.2 Postmarketing Experience The following adverse reactions have been identified during postapproval use of fluorouracil. Because these reactions are reported voluntarily from a population of uncertain size, it is not always possible to reliably estimate their frequency or establish a causal relationship to drug exposure. Hematologic: pancytopenia [see Warnings and Precautions ( 5.7 )] Gastrointestinal: gastrointestinal ulceration, nausea, vomiting Allergic Reactions: anaphylaxis and generalized allergic reactions Neurologic: nystagmus, headache Dermatologic: dry skin; fissuring; photosensitivity, as manifested by erythema or increased pigmentation of the skin; vein pigmentation Ophthalmic: lacrimal duct stenosis, visual changes, lacrimation, photophobia Psychiatric: euphoria Miscellaneous: thrombophlebitis, epistaxis, nail changes (including loss of nails)

7 DRUG INTERACTIONS [Enter highlight text here] 7.1 Anticoagulants and CYP 2C9 Substrates. Elevated coagulation times have been reported in patients taking fluorouracil concomitantly with warfarin. While pharmacokinetic data are not available to assess the effect of fluorouracil administration on warfarin pharmacokinetics, the elevation of coagulation times that occurs with the fluorouracil prodrug capecitabine is accompanied by an increase in warfarin concentrations. Thus, the interaction may be due to inhibition of cytochrome P450 2C9 by fluorouracil or its metabolites

8 USE IN SPECIFIC POPULATIONS •Nursing Mothers: Discontinue drug or discontinue nursing. ( 8.3 ) •Females and Males of Reproductive Potential: Provide pregnancy planning and prevention counseling. ( 5.10 , 8.1 , 8.6 ) 8.1 Pregnancy Pregnancy Category D Risk Summary There are no adequate and well-controlled studies with fluorouracil in pregnant women. Based on its mechanism of action, fluorouracil can cause fetal harm when administered to a pregnant woman. Administration of fluorouracil to rats and mice during selected periods of organogenesis, at doses lower than a human dose of 12 mg/kg, caused embryolethality and teratogenicity. Malformations included cleft palate and skeletal defects. In monkeys, maternal doses of fluorouracil higher than an approximate human dose of 12 mg/kg resulted in abortion. If this drug is used during pregnancy, or if the patient becomes pregnant while taking this drug, apprise the patient of the potential hazard to a fetus [see Clinical Pharmacology ( 12.1 )]. Animal Data Malformations including cleft palate, skeletal defects and deformed appendages (paws and tails) were observed when fluorouracil was administered by intraperitoneal injection to mice at doses at or above 10 mg/kg (approximately 0.06 times a human dose of 12 mg/kg on a mg/m 2 basis) for 4 days during the period of organogenesis. Similar results were observed in hamsters administered fluorouracil intramuscularly at doses lower than those administered in commonly used clinical treatment regimens. In rats, administration of fluorouracil by intraperitoneal injection at doses greater than 15 mg/kg (approximately 0.2 times a human dose of 12 mg/kg on a mg/m 2 basis) for a single day during organogenesis resulted in delays in growth and malformations including microanophthalmos. In monkeys, administration of fluorouracil during organogenesis at doses approximately equal to a human dose of 12 mg/kg on a mg/m 2 basis resulted in abortion; at a 50% lower dose, resorptions and decreased fetal body weights were reported. 8.3 Nursing Mothers It is not known whether fluorouracil or its metabolites are present in human milk. Because many drugs are present in human milk and because of the potential for serious adverse reactions in nursing infants from fluorouracil, a decision should be made whether to discontinue nursing or to discontinue the drug, taking into account the importance of the drug to the mother. 8.4 Pediatric Use The safety and effectiveness in pediatric patients have not been established. 8.5 Geriatric Use Reported clinical experience has not identified differences in safety or effectiveness between the elderly and younger patients. 8.6 Females and Males of Reproductive Potential Contraception Females Based on its mechanism of action, fluorouracil can cause fetal harm when administered to a pregnant woman. Advise females of reproductive potential to use effective contraception during treatment with fluorouracil and for up to 3 months following cessation of therapy [see Use in Specific Populations ( 8.1 )]. Males Fluorouracil may damage spermatozoa. Advise males with female partners of reproductive potential to use effective contraception during and for 3 months following cessation of therapy with fluorouracil [see Nonclinical Toxicology ( 13.1 )]. Infertility Females Advise females of reproductive potential that, based on animal data, fertility may be impaired while receiving fluorouracil [see Nonclinical Toxicology ( 13.1 )].

e effective contraception during and for 3 months following cessation of therapy with fluorouracil [see Nonclinical Toxicology ( 13.1 )]. Infertility Females Advise females of reproductive potential that, based on animal data, fertility may be impaired while receiving fluorouracil [see Nonclinical Toxicology ( 13.1 )]. Males Advise males of reproductive potential that, based on animal data, fertility may be impaired while receiving fluorouracil [see Nonclinical Toxicology ( 13.1 )].

8.1 Pregnancy Pregnancy Category D Risk Summary There are no adequate and well-controlled studies with fluorouracil in pregnant women. Based on its mechanism of action, fluorouracil can cause fetal harm when administered to a pregnant woman. Administration of fluorouracil to rats and mice during selected periods of organogenesis, at doses lower than a human dose of 12 mg/kg, caused embryolethality and teratogenicity. Malformations included cleft palate and skeletal defects. In monkeys, maternal doses of fluorouracil higher than an approximate human dose of 12 mg/kg resulted in abortion. If this drug is used during pregnancy, or if the patient becomes pregnant while taking this drug, apprise the patient of the potential hazard to a fetus [see Clinical Pharmacology ( 12.1 )]. Animal Data Malformations including cleft palate, skeletal defects and deformed appendages (paws and tails) were observed when fluorouracil was administered by intraperitoneal injection to mice at doses at or above 10 mg/kg (approximately 0.06 times a human dose of 12 mg/kg on a mg/m 2 basis) for 4 days during the period of organogenesis. Similar results were observed in hamsters administered fluorouracil intramuscularly at doses lower than those administered in commonly used clinical treatment regimens. In rats, administration of fluorouracil by intraperitoneal injection at doses greater than 15 mg/kg (approximately 0.2 times a human dose of 12 mg/kg on a mg/m 2 basis) for a single day during organogenesis resulted in delays in growth and malformations including microanophthalmos. In monkeys, administration of fluorouracil during organogenesis at doses approximately equal to a human dose of 12 mg/kg on a mg/m 2 basis resulted in abortion; at a 50% lower dose, resorptions and decreased fetal body weights were reported.

8.3 Nursing Mothers It is not known whether fluorouracil or its metabolites are present in human milk. Because many drugs are present in human milk and because of the potential for serious adverse reactions in nursing infants from fluorouracil, a decision should be made whether to discontinue nursing or to discontinue the drug, taking into account the importance of the drug to the mother.

11 DESCRIPTION Fluorouracil injection USP, a nucleoside metabolic inhibitor, is a colorless to faint yellow, aqueous, sterile, nonpyrogenic injectable solution available in 10 mL and 20 mL, a sterile preparation that contains single dose vial for intravenous administration. Each mL contains 50 mg fluorouracil in water for injection, USP. The pH is adjusted to approximately 9.2 with sodium hydroxide. Chemically, fluorouracil, a fluorinated pyrimidine, is 5-fluoro-2,4 (1H,3H)-pyrimidinedione. Its structural formula is: Molecular formula: C 4 H 3 FN 2 O 2 Molecular weight : 130.08 g/mole Fluorouracil-Structure

12 CLINICAL PHARMACOLOGY 12.1 Mechanism of Action Fluorouracil is a nucleoside metabolic inhibitor that interferes with the synthesis of deoxyribonucleic acid (DNA) and to a lesser extent inhibits the formation of ribonucleic acid (RNA); these affect rapidly growing cells and may lead to cell death. Fluorouracil is converted to three main active metabolites: 5-fluoro-2′-deoxyuridine-5′-monophosphate (FdUMP), 5-fluorouridine-5′triphosphate (FUTP) and 5-fluoro-2′-deoxyuridine-5′-triphosphate (FdUTP). These metabolites have several effects including the inhibition of thymidylate synthase by FdUMP, incorporation of FUTP into RNA and incorporation of FdUTP into DNA. 12.3 Pharmacokinetics Distribution Following bolus intravenous injection, fluorouracil distributes throughout the body including the intestinal mucosa, bone marrow, liver, cerebrospinal fluid and brain tissue. Elimination Following bolus intravenous injection, 5 – 20 % of the parent drug is excreted unchanged in the urine in six hours. The remaining percentage of the administered dose is metabolized, primarily in the liver. The metabolites of fluorouracil (e.g., urea and α-fluoro-ßalanine) are excreted in the urine over 3 to 4 hours. Following bolus intravenous injection of fluorouracil, as a single agent, the elimination half-life increased with dose from 8 to 20 minutes. 12.5 Pharmacogenomics The DPYD gene encodes the enzyme DPD, which is responsible for the catabolism of >80% of fluorouracil. Approximately 3-5% of White populations have partial DPD deficiency and 0.2% of White populations have complete DPD deficiency, which may be due to certain genetic no function or decreased function variants in DPYD resulting in partial to complete or near complete absence of enzyme activity. DPD deficiency is estimated to be more prevalent in Black or African American populations compared to White populations. Insufficient information is available to estimate the prevalence of DPD deficiency in other populations. Patients who are homozygous or compound heterozygous for no function DPYD variants (i.e., carry two DPYD variants that result in no DPD enzyme activity) or are compound heterozygous for a no function DPYD variant plus a decreased function DPYD variant have complete DPD deficiency and are at increased risk for acute early-onset of toxicity and serious life-threatening, or fatal adverse reactions with fluorouracil. Partial DPD deficiency can result from the presence of either two decreased function DPYD variants or one normal function plus either a decreased function or a no function DPYD variant. Patients with partial DPD deficiency may also be at an increased risk for toxicity from fluorouracil. Several DPYD variants observed with variable frequency across populations have been associated with reduced or no DPD activity, especially when present as homozygous or compound heterozygous variants. These include c.1905+1G>A (DPYD *2A), c.1679T>G (DPYD *13), c.2846A>T, c.1129-5923C>G (Haplotype B3), and c557A>G. DPYD*2A and DPYD*13 are no function variants, and c.2846A>T, c.1129- 5923C>G, and c557A>G are decreased function variants. This is not a complete listing of all DPYD variants that may result in DPD deficiency [see Warnings and Precautions ( 5.1 )].

12.1 Mechanism of Action Fluorouracil is a nucleoside metabolic inhibitor that interferes with the synthesis of deoxyribonucleic acid (DNA) and to a lesser extent inhibits the formation of ribonucleic acid (RNA); these affect rapidly growing cells and may lead to cell death. Fluorouracil is converted to three main active metabolites: 5-fluoro-2′-deoxyuridine-5′-monophosphate (FdUMP), 5-fluorouridine-5′triphosphate (FUTP) and 5-fluoro-2′-deoxyuridine-5′-triphosphate (FdUTP). These metabolites have several effects including the inhibition of thymidylate synthase by FdUMP, incorporation of FUTP into RNA and incorporation of FdUTP into DNA.

12.3 Pharmacokinetics Distribution Following bolus intravenous injection, fluorouracil distributes throughout the body including the intestinal mucosa, bone marrow, liver, cerebrospinal fluid and brain tissue. Elimination Following bolus intravenous injection, 5 – 20 % of the parent drug is excreted unchanged in the urine in six hours. The remaining percentage of the administered dose is metabolized, primarily in the liver. The metabolites of fluorouracil (e.g., urea and α-fluoro-ßalanine) are excreted in the urine over 3 to 4 hours. Following bolus intravenous injection of fluorouracil, as a single agent, the elimination half-life increased with dose from 8 to 20 minutes.

13 NONCLINICAL TOXICOLOGY 13.1 Carcinogenesis & Mutagenesis & Impairment Of Fertility Carcinogenicity studies have not been performed with fluorouracil. Fluorouracil was mutagenic in vitro in the bacterial reverse mutation (Ames) assay and induced chromosomal aberrations in hamster fibroblasts in vitro and in mouse bone marrow in the in vivo mouse micronucleus assay. Administration of fluorouracil intraperitoneally to male rats at dose levels equal to or greater than 1.7-fold the human dose of 12 mg/kg induced chromosomal aberrations in spermatogonia and inhibition of spermatogonia differentiation resulting in transient infertility. In female rats, intraperitoneal administration of fluorouracil during the pre-ovulatory phases of oogenesis at dose levels equal to or greater than 0.33 times a human dose of 12 mg/kg resulted in decreased incidence of fertile matings, increased pre-implantation loss, and fetotoxicity.

13.1 Carcinogenesis & Mutagenesis & Impairment Of Fertility Carcinogenicity studies have not been performed with fluorouracil. Fluorouracil was mutagenic in vitro in the bacterial reverse mutation (Ames) assay and induced chromosomal aberrations in hamster fibroblasts in vitro and in mouse bone marrow in the in vivo mouse micronucleus assay. Administration of fluorouracil intraperitoneally to male rats at dose levels equal to or greater than 1.7-fold the human dose of 12 mg/kg induced chromosomal aberrations in spermatogonia and inhibition of spermatogonia differentiation resulting in transient infertility. In female rats, intraperitoneal administration of fluorouracil during the pre-ovulatory phases of oogenesis at dose levels equal to or greater than 0.33 times a human dose of 12 mg/kg resulted in decreased incidence of fertile matings, increased pre-implantation loss, and fetotoxicity.

16 HOW SUPPLIED/STORAGE AND HANDLING 16.1 How Supplied Fluorouracil injection USP is supplied in single dose vial available in a box containing ten vials, as listed below: • NDC 68001-524-28: Vial containing 500 mg/10 mL (50 mg/mL) fluorouracil • NDC 68001-524-29: Vial containing 1 g/20 mL (50 mg/mL) fluorouracil 10 mL vials are packaged 10 vials per shelf pack with NDC 68001-524-30 20 mL vials are packaged 10 vials per shelf pack with NDC 68001-524-31 16.2 Storage Store at 20°C to 25°C (68°F to 77°F). Excursions are permitted from 15°C to 30°C (59°F to 86°F) [see USP Controlled Room Temperature]. Protect from light. Retain in carton until time of use. Fluorouracil is a cytotoxic drug. Follow applicable special handling and disposable procedures [see References ( 15 )] 16.1 How Supplied Fluorouracil injection USP is supplied in single dose vial available in a box containing ten vials, as listed below: • NDC 68001-524-28: Vial containing 500 mg/10 mL (50 mg/mL) fluorouracil • NDC 68001-524-29: Vial containing 1 g/20 mL (50 mg/mL) fluorouracil 10 mL vials are packaged 10 vials per shelf pack with NDC 68001-524-30 20 mL vials are packaged 10 vials per shelf pack with NDC 68001-524-31

16.2 Storage Store at 20°C to 25°C (68°F to 77°F). Excursions are permitted from 15°C to 30°C (59°F to 86°F) [see USP Controlled Room Temperature]. Protect from light. Retain in carton until time of use. Fluorouracil is a cytotoxic drug. Follow applicable special handling and disposable procedures [see References ( 15 )]

17 PATIENT COUNSELING INFORMATION Advise: • Prior to initiating fluorouracil treatment, inform patients of the potential for serious or fatal adverse reactions due to DPD deficiency and testing for genetic variants of DPYD. Advise patients to immediately contact their healthcare provider if symptoms of severe mucositis, diarrhea, neutropenia, and neurotoxicity occur [see Warnings and Precautions( 5.1 ) and Clinical Pharmacology ( 12.5 )]. •Patients of the risk of cardiotoxicity. Advise patients to immediately contact their healthcare provider or to go to an emergency room for new onset of chest pain, shortness of breath, dizziness, or lightheadedness [see Warnings and Precautions ( 5.2 )]. •Patients to immediately contact their healthcare provider or go to an emergency room for new onset of confusion, disorientation, or otherwise altered mental status; difficulty with balance or coordination; or visual disturbances [see Warnings and Precautions ( 5.3 , 5.4 )]. •Patients to contact their healthcare provider for severe diarrhea or for painful mouth sores with decreased oral intake of food or fluids [see Warnings and Precautions ( 5.5 , 5.8 )]. •Patients to contact their healthcare provider for tingling or burning, redness, flaking, swelling, blisters, or sores on the palms of their hands or soles of their feet [see Warnings and Precautions ( 5.6 )]. •Patients of the importance of keeping appointments for blood tests. Instruct patients to monitor their temperature on a daily basis and to immediately contact their healthcare provider for fever or other signs of infection [see Warnings and Precautions ( 5.7 )]. •Patients to notify their healthcare provider of all drugs they are taking, including warfarin or other coumarin-derivative anticoagulants. Advise patients of the importance of keeping appointments for blood tests [see Warnings and Precautions ( 5.9 )]. •Females of reproductive potential and males with female partners of reproductive potential to use effective contraception during treatment with fluorouracil and for up to 3 months after the last dose of fluorouracil. Instruct female patients to contact their healthcare provider if they become pregnant, if pregnancy occurs during fluorouracil treatment or during the 3 months following the last dose [see Warnings and Precautions ( 5.10 ), Use in Specific Populations ( 8.1 and 8.6 ), and Nonclinical Toxicology ( 13.1 )]. •Females and males of reproductive potential may have impaired fertility while receiving fluorouracil, based on animal data [see Use in Specific Populations (8.6) and Nonclinical Toxicology ( 13.1 )]. •Nursing mothers to discontinue nursing [see Use in Specific Populations ( 8.3 )]. Manufactured by: Gland Pharma limited Unit-II, Block-C, Phase-1, VSEZ, Duvvada Visakhapatnam - 530049 Andhra Pradesh India. For BluePoint Laboratories Revised: 01/2026