trifarotene + doxycycline

**Trifarotene + doxycycline** is a fixed regimen combining a topical fourth-generation retinoid (trifarotene) with an oral tetracycline antibiotic (doxycycline), used for the treatment of moderate to severe acne vulgaris. Trifarotene acts as a selective retinoic acid receptor gamma agonist, decreasing inflammation and promoting the turnover of skin cells, thereby reducing comedones and inflammatory lesions. Doxycycline is a broad-spectrum antibiotic that inhibits bacterial protein synthesis (primarily targeting Cutibacterium acnes) and provides significant anti-inflammatory effects. The combination is designed to leverage the complementary mechanisms of both drugs, resulting in greater efficacy than either agent alone, especially noted in moderate to severe acne. Multiple prospective, randomized trials report significant reductions in both inflammatory and non-inflammatory acne lesions, as well as improvement in investigator global assessment scores following 8-12 weeks of combination therapy. The regimen has demonstrated safety and tolerability comparable to monotherapies, with mostly mild-to-moderate adverse effects reported.