AP4500

AP4500 is a novel 2.4% topical solution of terbinafine hydrochloride developed by Onyx Axiom for the treatment of mild to moderate onychomycosis (toenail fungus). Terbinafine is a well-established allylamine antifungal that exerts its effect by inhibiting squalene monooxygenase (squalene epoxidase), a critical enzyme in the fungal ergosterol biosynthesis pathway. This inhibition leads to an accumulation of intracellular squalene and a deficiency in ergosterol, which disrupts fungal cell membrane integrity and results in fungal cell death. Unlike traditional topical terbinafine formulations that often struggle with poor nail plate penetration, AP4500 is specifically engineered to enhance the absorption of the active ingredient through the nail to reach the subungual site of infection directly. It is currently being evaluated in Phase 2 clinical trials comparing its efficacy and safety to vehicle control and the commercial comparator efinaconazole (Jublia).

Other names

2.4% terbinafine hydrochloride topical solutiontopical terbinafine hydrochloride