A treatment for severe nodular acne: a randomized investigator‐blinded, controlled, noninferiority trial comparing fixed‐dose adapalene/benzoyl peroxide plus doxycycline vs. oral isotretinoin

BACKGROUND: Oral isotretinoin (ISO) is the gold standard for severe nodular acne. However, as some patients are unwilling or unable to take, or are intolerant to, ISO, other options are needed. OBJECTIVES: To compare efficacy and safety of oral ISO vs. doxycycline 200 mg plus adapalene 0·1%/benzoyl peroxide 2·5% gel (D+A/BPO) in severe nodular acne over 20 weeks.