Clindamycin Phosphate

1 INDICATIONS AND USAGE Clindamycin phosphate foam is indicated for topical application in the treatment of acne vulgaris in patients 12 years and older. Clindamycin phosphate foam is a lincosamide product indicated for acne vulgaris in patients 12 years and older. ( 1 )

2 DOSAGE AND ADMINISTRATION Clindamycin phosphate foam is for topical use only, and not for oral, ophthalmic, or intravaginal use. Apply clindamycin phosphate foam once daily to affected areas after the skin is washed with mild soap and allowed to fully dry. Use enough to cover the entire affected area. If there has been no improvement after 6 to 8 weeks or if the condition becomes worse, treatment should be discontinued. The contents of clindamycin phosphate foam are flammable; avoid fire, flame and/or smoking during and immediately following application. • For topical use only; not for oral, ophthalmic, or intravaginal use. ( 2 ) • Apply clindamycin phosphate foam once daily to affected areas. ( 2 ) • Flammable; avoid fire, flame and/or smoking during and immediately following application. ( 2 )

5 WARNINGS AND PRECAUTIONS • Colitis: Clindamycin can cause severe colitis, which may result in death. Diarrhea, bloody diarrhea, and colitis (including pseudomembranous colitis) have been reported with the use of clindamycin. Clindamycin phosphate foam should be discontinued if significant diarrhea occurs. ( 5.1 ) 5.1 Colitis Systemic absorption of clindamycin has been demonstrated following topical use of this product. Diarrhea, bloody diarrhea, and colitis (including pseudomembranous colitis) have been reported with the use of topical clindamycin. If significant diarrhea occurs, clindamycin phosphate foam should be discontinued [ see Adverse Reactions ( 6.2 ) ]. Severe colitis has occurred following oral or parenteral administration of clindamycin with an onset of up to several weeks following cessation of therapy. Antiperistaltic agents such as opiates and diphenoxylate with atropine may prolong and/or worsen severe colitis. Severe colitis may result in death. Studies indicate a toxin(s) produced by Clostridia is one primary cause of antibiotic-associated colitis. The colitis is usually characterized by severe persistent diarrhea and severe abdominal cramps and may be associated with the passage of blood and mucus. Stool cultures for Clostridium difficile and stool assay for C. difficile toxin may be helpful diagnostically. 5.2 Irritation Clindamycin phosphate foam can cause irritation. Concomitant topical acne therapy should be used with caution since a possible cumulative irritancy effect may occur, especially with the use of peeling, desquamating, or abrasive agents. If irritation or dermatitis occurs, clindamycin should be discontinued. Avoid contact of clindamycin phosphate foam with eyes, mouth, lips, other mucous membranes or areas of broken skin. If contact occurs, rinse thoroughly with water. Clindamycin phosphate foam should be prescribed with caution in atopic individuals.

4 CONTRAINDICATIONS Clindamycin phosphate foam is contraindicated in individuals with a history of regional enteritis or ulcerative colitis, or a history of antibiotic-associated colitis (including pseudomembranous colitis). Clindamycin phosphate foam is contraindicated in individuals with a history of regional enteritis or ulcerative colitis, or a history of antibiotic-associated colitis (including pseudomembranous colitis). ( 4 )

7 DRUG INTERACTIONS 7.1 Erythromycin Clindamycin phosphate foam should not be used in combination with topical or oral erythromycin-containing products due to possible antagonism to its clindamycin component. In vitro studies have shown antagonism between these two antimicrobials. The clinical significance of this in vitro antagonism is not known. 7.2 Neuromuscular Blocking Agents Clindamycin has been shown to have neuromuscular blocking properties that may enhance the action of other neuromuscular blocking agents. Therefore, clindamycin phosphate foam should be used with caution in patients receiving such agents.

8.1 Pregnancy Risk Summary There are no available data on clindamycin phosphate foam use in pregnant women to inform a drug-associated risk for adverse developmental outcomes. Animal reproduction studies have not been conducted with clindamycin phosphate foam. No evidence of fetal harm or malformations was observed in pregnant rats and mice administered daily subcutaneous or oral doses of clindamycin salts during organogenesis at doses that produced exposures up to 84 and 42 times, respectively, the maximum recommended human dose (MRHD) of clindamycin phosphate foam based on body surface area (BSA) comparisons and assuming 100% absorption [see Data] . In the U.S. general population, the estimated background risk of major birth defects and miscarriage in clinically recognized pregnancies is 2 to 4% and 15 to 20%, respectively. Data Animal Data Reproduction studies have been conducted in rats and mice using subcutaneous or oral doses of clindamycin phosphate, clindamycin hydrochloride or clindamycin palmitate hydrochloride administered daily during organogenesis at doses up to the equivalent of 432 mg/kg/day clindamycin phosphate. These studies produced no evidence of fetal harm or malformations in rats or mice at exposures 84 or 42 times, respectively, the MRHD of clindamycin phosphate (i.e., 5 milliliters of clindamycin phosphate foam) based on BSA comparison and assuming 100% absorption.

6 ADVERSE REACTIONS The most common adverse reactions (>1%) are headache and application site reactions including burning, pruritus, and dryness. ( 6.1 ) To report SUSPECTED ADVERSE REACTIONS, contact Glenmark Pharmaceuticals Inc., USA at 1 (888) 721-7115 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 clinical practice. A total of 439 subjects with mild to moderate acne vulgaris were treated once daily for 12 weeks with clindamycin phosphate foam. The incidence of adverse reactions occurring in ≥ 1% of the subjects in clinical trials comparing clindamycin phosphate foam and its vehicle is presented in Table 1. Table 1: Adverse Reactions Occurring in ≥ 1% of Subjects Adverse Reactions Number (%) of Subjects Clindamycin Phosphate Foam Vehicle Foam N = 439 N = 154 Headache 12 (3%) 1 (1%) Application site burning 27 (6%) 14 (9%) Application site pruritus 5 (1%) 5 (3%) Application site dryness 4 (1%) 5 (3%) Application site reaction, not otherwise specified 3 (1%) 4 (3%) In a contact sensitization study, none of the 203 subjects developed evidence of allergic contact sensitization to clindamycin phosphate foam. 6.2 Postmarketing Experience The following adverse reactions have been identified during post approval use of clindamycin phosphate foam: application site pain, application site erythema, diarrhea, urticaria, abdominal pain, hypersensitivity, rash, abdominal discomfort, nausea, seborrhea, application site rash, dizziness, pain of skin, colitis (including pseudomembranous colitis), and hemorrhagic diarrhea. 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. Abdominal pain and gastrointestinal disturbances, as well as gram-negative folliculitis, have also been reported in association with the use of topical formulations of clindamycin. Orally and parenterally administered clindamycin have been associated with severe colitis, which may end fatally.