Double-Blinded, Vehicle-Controlled Proof of Concept Study to Investigate the Recurrence of Inflammatory and Noninflammatory Acne Lesions Using Tretinoin Gel (Microsphere) 0.04% in Male Patients after Oral Isotretinoin Use

Background. Although isotretinoin orally is commonly used for moderate to severe or scarring acne, it is not a cure. Unfortunately recurrence is unpredictable and varies within the acne population. Objectives. Using a proof of concept study, determine the recurrence of acne after isotretinoin use in male patients. Methods. Twenty males aged 18–45 years old were enrolled. Subjects successfully completed a treatment of acne vulgaris with oral isotretinoin (120–150？mg/kg/course). Subjects were randomized 1 to 1. The study duration was 24 weeks. The primary endpoint measured was the absolute change in lesion counts from baseline to weeks 16 and 24. Local tolerability assessments were measured. Results. There were favorable changes in all outcomes measured. Overall, there was a 38.7% lower lesion count with tretinoin 0.04% microsphere gel use versus vehicle. The active product was well tolerated with great patient satisfaction. There were no significant safety issues. The limitations included the low number of patients enrolled, average age, and percentage of patients lost to follow-up. Conclusion. In summary, the results favored tretinoin 0.04% microsphere gel in the prevention of recurrent acne after isotretinoin use in male patients over 18 years old over a six-month period. 1. Introduction Acne is a common dermatological disorder that affects millions of North American adolescents and young adults. Although isotretinoin orally is commonly used for moderate to severe or scarring acne, it is not a cure. Even postisotretinoin acne can recur. The use of topical retinoids is part of basic and early acne treatment to treat comedonal noninflammatory acne lesions and occasional inflammatory lesions. After oral isotretinoin, it is not uncommon for comedones as well as noninflammatory and inflammatory papules to recur. Unfortunately this is unpredictable and varies within the acne population. Despite this, there has been no formal study to look at the prevention of recurrence of these acne lesions after isotretinoin. This information may enhance the therapeutic options for postisotretinoin patients in order to prevent recurrence of their disease. The study product was tretinoin 0.04% gel (microsphere) indicated for the topical treatment of acne vulgaris. 2. Materials and Methods 2.1. Study Design This was a double-blinded vehicle controlled proof of concept study with an enrollment of 20 male subjects. Subjects were randomized 1？:？1 to study product or vehicle. Subjects were randomly assigned to each group by an unblinded dispenser. The study duration was 24 weeks