Acne Relapse and Isotretinoin Retrial in Patients With Acne.

Importance: Isotretinoin is the only medical acne treatment capable of inducing acne remission; however, some patients experience acne relapse and require retrials of isotretinoin. There is a need to understand who is most at risk and how daily dose and cumulative dosage can influence outcomes. Objective: To assess rates of acne relapse and isotretinoin retrial and to identify associated factors among patients with acne who received an isotretinoin treatment course. Design, Setting, and Participants: This cohort study used data from the MarketScan commercial claims database from January 1, 2017, to December 31, 2020, to identify patients with acne who were 12 years or older and had received isotretinoin for 4 months or longer, with at least 1 year of continuous enrollment after completion of isotretinoin. Data analyses were performed from June 30, 2024, to August 1, 2024. Main Outcomes and Measures: Multivariable Cox proportional hazards regression was used to quantify associations of patient demographic and treatment characteristics with acne relapse and isotretinoin retrial. Results: A total of 19 907 patients (mean [SD] age, 20.6 [7.8] years; 10 504 females [52.8%]) were included, among whom 4482 (22.5%) had acne relapse and 1639 (8.2%) had isotretinoin retrial. Female sex (hazard ratio [HR], 1.43; 95% CI, 1.35-1.52) was significantly associated with increased rates of acne relapse, and isotretinoin cumulative dosage (mg/kg) was associated with a decreased rate of acne relapse (HR, 0.996; 95% CI, 0.995-0.997). Furthermore, daily dose was not associated with decreased risk of acne relapse or isotretinoin retrial among those with conventional and high cumulative dosages. Female sex (HR, 0.68; 95% CI, 0.62-0.76) and isotretinoin cumulative dosage (HR, 0.99; 95% CI, 0.98-0.99) were associated with decreased rates of isotretinoin retrial. Stratification by cumulative dosage indicated that higher cumulative dosage was associated with decreased rates of retrial among patients with low (<120 mg/kg) and conventional (120-220 mg/kg), but not high (>220 mg/kg) cumulative dosage. Maximum daily dose (mg/kg/d) was not negatively associated with acne relapse or isotretinoin retrial in patients with cumulative dosage of 120 mg/kg or more. Conclusions and Relevance: The findings of this cohort study suggest that higher cumulative dosage may potentially reduce risk of acne relapse and isotretinoin retrial. Furthermore, daily dose was not associated with decreased risk of the outcomes for conventional and high cumulative dosage; therefore, daily dosing could be individualized to patient goals and preferences.