explanation may be that sarecycline exerts anti-inflammatory effects on an early inflammatory process that is postulated to occur during the development of comedones.11,12 Antibiotic resistance is a concern with oral antibiotic treatments for acne.3-7 Agents that unnecessarily target a broad spectrum of bacteria are associated with greater potential for antibiotic resistance,13 and the American Academy of Dermatology recommends responsible usage of systemic antibiotics for acne.1 The current first-line antibiotics for moderate to severe acne are broad-spectrum tetracycline-class antibiotics, such as minocycline and doxycycline,1 highlighting the need for a narrow-spectrum antibiotic that can be used as first-line treatment for moderate to severe acne. In vitro studies have demonstrated the narrow antibacterial spectrum of sarecycline and its limited activity against enteric gram-negative bacteria (Data on file; Allergan plc, Dublin, Ireland).The antibacterial profile of sarecycline, particularly its targeted activity against P. acnes, may reduce its potential for disrupting the human gut microbiome. In contrast, administration of the tetracycline-class antibiotics doxycycline, minocycline, and tetracycline has been associated with disruption of the gut microbiome.14-16 The favorable safety profile of sarecycline in these studies represents an important finding for a tetracycline-class antibiotic. Tetracycline-class antibiotics may be associated with GI side effects and phototoxicity (typically seen with doxycycline) or vestibular side effects (observed with minocycline),3 yet low rates of such side effects were reported in these studies with sarecycline. In the current phase 3 studies, the incidence of AEs related to the GI tract, including nausea, vomiting, diarrhea, and abdominal pain, was low.
