Clindamycin Phosphate and Benzoyl Peroxide

Clindamycin Phosphate and Benzoyl Peroxide Gel, 1.2%/3.75% is indicated for the topical treatment of acne vulgaris in patients 12 years of age and older. Clindamycin Phosphate and Benzoyl Peroxide Gel is a combination of clindamycin phosphate (a lincosamide antibacterial) and benzoyl peroxide indicated for the topical treatment of acne vulgaris in patients 12 years of age and older. ( 1 )

Gel, 1.2%/3.75% Each gram of clindamycin phosphate and benzoyl peroxide gel contains 12 mg (1.2%) clindamycin phosphate, equivalent to 10 mg (1%) clindamycin, and 37.5 mg (3.75%) benzoyl peroxide in a white to off-white, opaque, smooth gel. Gel, 1.2% clindamycin phosphate/3.75% benzoyl peroxide

Clindamycin Phosphate and Benzoyl Peroxide Gel is contraindicated in:

• Patients who have demonstrated hypersensitivity (e.g., anaphylaxis) to clindamycin, benzoyl peroxide, any components of the formulation, or lincomycin. ( 4.1 )
• Patients with a history of regional enteritis, ulcerative colitis, or antibiotic-associated colitis. ( 4.2 )

4.1 Hypersensitivity Clindamycin Phosphate and Benzoyl Peroxide Gel is contraindicated in those individuals who have shown hypersensitivity to clindamycin, benzoyl peroxide, any components of the formulation, or lincomycin. Anaphylaxis, as well as allergic reactions leading to hospitalization, has been reported in postmarketing use with clindamycin phosphate and benzoyl peroxide gel [see Postmarketing Experience (6.2) ] .

4.2 Colitis/Enteritis Clindamycin Phosphate and Benzoyl Peroxide Gel is contraindicated in patients with a history of regional enteritis, ulcerative colitis, or antibiotic-associated colitis [see Warnings and Precautions (5.1) ] .

• 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 and Benzoyl Peroxide Gel should be discontinued if significant diarrhea occurs. ( 5.1 )
• Ultraviolet Light and Environmental Exposure: Minimize sun exposure following drug application. ( 5.2 )

5.1 Colitis Systemic absorption of clindamycin has been demonstrated following topical use of clindamycin. Diarrhea, bloody diarrhea, and colitis (including pseudomembranous colitis) have been reported with the use of topical and systemic clindamycin. If significant diarrhea occurs, clindamycin phosphate and benzoyl peroxide gel should be discontinued. Severe colitis has occurred following oral and 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 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 Ultraviolet Light and Environmental Exposure Minimize sun exposure (including use of tanning beds or sun lamps) following drug application.

5.3 Concomitant Topical Medications 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 irritancy or dermatitis occurs, reduce frequency of application or temporarily interrupt treatment and resume once the irritation subsides. Treatment should be discontinued if the irritation persists.

The following adverse reaction is described in more detail in the Warnings and Precautions section of the label:

• Colitis [see Warnings and Precautions (5.1) ] . The most common adverse reactions are: burning sensation (0.4%); contact dermatitis (0.4%); pruritus (0.4%); and rash (0.4%). ( 6.1 ) To report SUSPECTED ADVERSE REACTIONS, contact Oceanside Pharmaceuticals at 1-800-321-4576 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 clinical trials of a drug cannot be directly compared to rates observed in clinical trials of another drug and may not reflect the rates observed in clinical practice. These adverse reactions occurred in less than 0.5% of subjects treated with clindamycin phosphate and benzoyl peroxide gel: burning sensation (0.4%); contact dermatitis (0.4%); pruritus (0.4%); and rash (0.4%). During the clinical trial, subjects were assessed for local cutaneous signs and symptoms of erythema, scaling, itching, burning and stinging. Most local skin reactions either were the same as baseline or increased and peaked around Week 4 and were near or improved from baseline levels by Week 12. The percentage of subjects that had symptoms present before treatment (at baseline), during treatment, and the percent with symptoms present at Week 12 are shown in Table 1. Table 1: Percent of Subjects with Local Skin Reactions. Results from the Phase 3 Trial (N = 243) Before Treatment (Baseline) During Treatment End of Treatment (Week 12) Mild Mod. * Severe Mild Mod. * Severe Mild Mod. * Severe Erythema 20 6 0 28 5 <1 15 2 0 Scaling 10 1 0 19 3 0 10 <1 0 Itching 14 3 <1 15 3 0 7 2 0 Burning 5 <1 <1 7 1 <1 3 <1 0 Stinging 5 <1 0 7 0 <1 3 0 <1 *Mod. = Moderate

6.2 Postmarketing Experience Because postmarketing adverse 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. Anaphylaxis, as well as allergic reactions leading to hospitalizations, has been reported in postmarketing use of products containing clindamycin phosphate/benzoyl peroxide.

Avoid using clindamycin phosphate and benzoyl peroxide gel in combination with topical or oral erythromycin-containing products because of its clindamycin component. ( 7.1 )

7.1 Erythromycin Avoid using clindamycin phosphate and benzoyl peroxide gel in combination with topical or oral erythromycin-containing products due to its clindamycin component. In vitro studies have shown antagonism between erythromycin and clindamycin. 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. Clindamycin Phosphate and Benzoyl Peroxide Gel should be used with caution in patients receiving such agents.

8.1 Pregnancy Risk Summary There are no available data on clindamycin phosphate and benzoyl peroxide gel use in pregnant women to evaluate a drug-associated risk of major birth defects, miscarriage, or adverse maternal or fetal outcomes. The limited published data on use of clindamycin in pregnant women with exposure during the first trimester are insufficient to inform a drug-associated risk of pregnancy-related adverse outcomes (see Data) . In limited published clinical trials with pregnant women, the systemic administration of clindamycin during the second and third trimesters has not been associated with an increased frequency of major birth defects. In animal reproduction studies, clindamycin did not cause malformations or embryo-fetal development toxicity in pregnant rats and mice when administered during the period of organogenesis at systemic doses up to 240 times the maximum recommended human dose (MRHD) of 2.5 g clindamycin phosphate and benzoyl peroxide gel, based on body surface area (BSA) comparisons (see Data) . The estimated background risk of major birth defects and miscarriage for the indicated population is unknown. All pregnancies have a background risk of major birth defects, loss, and other adverse outcomes. 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 Human Data In limited published trials in pregnant women administered clindamycin during the first trimester of pregnancy, there was no difference in the rate of major birth defects reported among in utero exposed infants compared to unexposed infants. These data cannot definitely establish or exclude any clindamycin-associated risk during pregnancy. Animal Data Animal reproductive/developmental toxicity studies have not been conducted with clindamycin phosphate and benzoyl peroxide gel or benzoyl peroxide. Developmental toxicity studies of clindamycin performed in pregnant rats and mice administered during the period of organogenesis at oral doses of up to 600 mg/kg/day (240 and 120 times the MRHD for clindamycin, respectively, based on BSA comparisons) or subcutaneous doses of up to 200 mg/kg/day (80 and 40 times the MRHD for clindamycin, respectively, based on BSA comparisons) revealed no malformations or embryo-fetal development toxicity.

8.2 Lactation Risk Summary There are no data on the presence of clindamycin or benzoyl peroxide in human milk, the effects on the breastfed child, or the effects on milk production following topical administration. However, clindamycin has been reported to be present in breast milk in small amounts following oral and parenteral administration. The developmental and health benefits of breastfeeding should be considered along with the mother’s clinical need for clindamycin phosphate and benzoyl peroxide gel and any potential adverse effects on the breastfed child from clindamycin phosphate and benzoyl peroxide gel or from the underlying maternal condition. Clinical Considerations If used during lactation and clindamycin phosphate and benzoyl peroxide gel is applied to the chest, care should be taken to avoid accidental ingestion by the infant.

8.4 Pediatric Use Safety and effectiveness of clindamycin phosphate and benzoyl peroxide gel in pediatric patients under the age of 12 years have not been evaluated.

8.5 Geriatric Use Clinical trials of clindamycin phosphate and benzoyl peroxide gel did not include sufficient numbers of subjects age 65 years and older to determine whether they respond differently from younger subjects.

Clindamycin: Clindamycin is a lincosamide antibacterial [see Microbiology (12.4) ] . Benzoyl Peroxide: Benzoyl peroxide is an oxidizing agent with bactericidal and keratolytic effects but the precise mechanism of action is unknown.