F2G Ltd, a UK- and Austria-based biotech company developing novel therapies for life-threatening systemic fungal infections, announced that the US Food and Drug Administration (FDA) has granted breakthrough therapy designation to its lead first-in-class candidate, olorofim (formerly F901318) for the indication of ‘Treatment of invasive mold infections in patients with limited or no treatment options, including aspergillosis refractory or intolerant to currently available therapy, and infections due to Lomentospora prolificans, Scedosporium, and Scopulariopsis species’. Olorofim is the first antifungal agent to be granted Breakthrough Therapy designation. Olorofim is currently being investigated in an open-label single-arm phase 2b study in patients with proven invasive fungal disease (IFD) or probable invasive aspergillosis (IA) and either refractory disease, resistance, or intolerance to available agents. Olorofim has been well tolerated across more than 10 years of patient dosing days with a median therapy duration of 12 weeks. Preliminary data from this study were provided to the FDA as part of the Breakthrough Therapy designation submission. Breakthrough Therapy designation is an FDA process designed to expedite the development and review of drugs that are intended to treat a serious or life-threatening condition and is granted based on preliminary clinical evidence indicating that the drug may demonstrate substantial improvement over existing therapies on one or more clinically significant endpoints. Breakthrough Therapy designation conveys all the features of fast track designation, more intensive FDA guidance on an efficient drug development program, an organisational commitment by FDA to involve senior managers, and eligibility for rolling review and priority review. Commenting on the news, Ian Nicholson, CEO of F2G Ltd, said, “The granting of FDA Breakthrough Therapy designation is a truly transformational step for our company and will support our goal of rapidly developing this novel treatment for patients suffering from serious and life-threatening fungal infections. Olorofim acts via a novel and differentiated mechanism to traditional antifungals, and preliminary data have indicated that it is efficacious in tackling life-threatening invasive fungal infections that cannot be managed with currently approved agents. “Our phase 2b programme is on track with over 40 patients recruited in Europe, Australia and the US. We look forward to working closely with the FDA to accelerate development of this therapy for patients having limited or no approved treatment options for an invasive mold infection.” Professor Sharon Chen, Westmead Hospital Sydney and Principal Investigator for the phase 2b study said, “This news is very exciting for clinicians caring for patients with these very serious, and devastating mold infections. We have had limited treatment options for many years and now the news about olorofim brings realistic hope that we can cure these previously treatment–refractory infections.