Pilot Study Supports Once-Daily Isotretinoin for Acne Treatment

Micronized isotretinoin administered once per day without food was effective and well-tolerated for the treatment of severe nodular acne, new study results indicate.

Researchers for the pilot study focused on and evaluated a regimen of once-daily micronized isotretinoin (0.4 to 0.8 mg/kg/day) without food. Patients with severe nodular acne who were aged 12 years and older were included in the study. The regimen using the microionized isotretinoin formulation, the researchers explained, was created with the goal of improving patient compliance with what has traditionally been a medication that requires the consumption of food to promote proper absorption.

"Due to its poor aqueous solubility, isotretinoin has historically required ingestion with food--specifically a high-fat meal with each dose--to ensure optimal absorption and consistent plasma concentrations of isotretinoin," the authors wrote in the study. "This makes patient adherence a concern, particularly in adolescents and young adults, who often exhibit inconsistent eating patterns such as skipping breakfast, and who are most often the recipients of treatment for acne vulgaris. Failure to adhere to recommendations to ingest each dose of isotretinoin with an adequate high-fat meal to promote drug absorption may result in lower cumulative exposure to isotretinoin over a course of therapy, which may adversely impact the likelihood of long-term remission."

The patients (N = 24) who had severe nodular acne (defined as (Investigator's Global Assessment [IGA] ≥4 and more than five facial nodules) were treated over 20 weeks. The primary efficacy measure was a reduction in nodular lesion count (NLC) and the percentage of patients achieving a ≥90% reduction in NLC at 24 weeks. Secondary endpoints included the proportion of patients reaching IGA 0/1, reductions in inflammatory lesion count (ILC) and non-inflammatory lesion count (NILC), adverse events (AEs), and changes in erythema, dryness, peeling, oiliness, burning, and pruritus.

A total of 22 patients completed the study. Median reduction in NLC was 6 (Q1: 5, Q3: 7) at 24 weeks. All patients experienced complete clearance of nodules, with 96% (23/24) achieving IGA 0/1. Mean reductions in ILC and NILC were 97.8% ± 5.7% and 98.4% ± 6.2%, respectively (all P<0.0001). The researchers reported early increases in erythema, dryness, and peeling, and all were mild. Two patients reported three adverse events not related to the treatment.

Source: Del Rosso J, et al. Journal of Drugs in Dermatology. 2024;23(6). Doi:10.36849/JDD.786