The objective of this study was to evaluate the efficacy and safety of the test formulation of adapalene gel 0.1% (PLIVA Research & Development Ltd.) as compared to the already marketed formulation, Differin® (adapalene 0.1%) topical gel (Galderma Laboratories) in patients with acne vulgaris.

Criteria for Evaluation: FDA Bioequivalence Criteria for Comparative Clinical Endpoint Studies.

Statistical Methods: FDA Bioequivalence Statistical Methods for Comparative Clinical Endpoint Studies.

Inclusion Criteria:

• Male or non-pregnant, non-lactating female, 12-40 years of age inclusive.
• Signed informed consent form, which meets all the criteria of the current FDA regulations. For patients under the age of majority in the state they are enrolled, the patient's parent or legal guardian will be required to sign the consent form and the patient will sign an IRB approved "assent to participate" form.
• If female and of child bearing potential, prepare to abstain from sexual intercourse or use reliable method of contraception during the study (i.e. condom, Intrauterine device, hormonal contraceptives). Patients on hormonal contraceptives must have been on the same hormonal contraceptive for 3 months prior to the baseline visit and continue throughout the duration of the study.
• Have moderate to severe facial acne as defines as: at least 20 but no more that 60 facial inflammatory lesions (papules and pustules) and at least 25 but no more than 100 non-inflamed lesions (open and closed comedones) and have a Physician's Global Assessment score of 3, 4, or 5.

Exclusion Criteria:

• Patient has more than 2 facial nodular lesions, any nodules present will be documented but will not be included in the inflammatory lesion count.
• Patient has active cystic acne.
• Patient has acne conglobate.
• Patient with significant facial hair such as beards or tattoos or excessive facial scarring that, in the Investigator's opinion, may interfere with the evaluation of the patient's acne.
• Patients with facial sunburn.
• Any dermatological condition other than acne vulgaris that, in the Investigator's opinion, may interfere with the evaluation of the patient's acne (e.g. rosacea, psoriasis, dermatitis).
• Females who are pregnant, lactating, or likely to become pregnant during the study.
• History of allergy or sensitivity to adapalene or other retinoids, or history of any drug hypersensitivity or intolerance which, in the Investigator's opinion, would compromise the safety of the patient or the study.
• Significant history or current evidence of chronic infectious disease, system disorder, organ disorder, or other medical condition that, in the Investigator's opinion, would place the study participant at undue risk by participation.
• Use of any topical antibiotics, topical steroids, or topical anti-inflammatory products used on the face, any oral antibiotics known to treat acne, any systemic steroids, or any systemic anti-inflammatory agents (other than the use of non-steroidal anti-inflammatory agents) within 28 days of the first dosing day.
• Use of oral isotretinoin (Accutane®) within 6 months. Use of topical tretinoin (Retin-A®), adapalene (Differin®), tazarotene (Tazorac®), or azelaic acid (Azelex®) within 28 days of the first dosing day.
• Receipt of any drug as part of a research study within 30 days prior to dosing.
• Female patients who are using hormonal contraceptives must have been on the same type and strength of hormonal contraceptive for at least 3 months prior to enrollment in the study and throughout the duration of the study.
• Patients should not use any medicated facial products (soaps, lotions, moisturizers, etc.) or other medicated facial cleansing agents for 14 days prior to study enrollment.
• Previous participation in this study.