Relief Therapeutics’ RLF-100 (aviptadil) received an 11-point boost in its likelihood of approval (LoA) as of 30 March, after the company announced a positive Phase II/III study in Covid-19.

Relief is developing aviptadil, a synthetic form of vasoactive intestinal peptide (VIP), in collaboration with Radnor, Pennsylvania-based NeuroRx. Relief will connect with European regulators once the full dataset is available and NeuroRx plans to apply for an Emergency Use Authorisation (EUA) based on these results, as per a 29 March press release. Additionally, a Phase II/III aviptadil study is scheduled to be initiated in Europe later this year.

The Phase II/III trial evaluated aviptadil’s efficacy in treating in critically ill Covid-19 patients and improved the recovery from respiratory failure—the trial’s primary outcome—at 28 days (p=0.014) and 60 days (p=0.013), as per the release. The FDA had specified the primary endpoint as recovery from respiratory failure, without relapse with discharge from acute care and survival through the observation period at 28 days, but as per recent guidance this was extended to 60 days. The trial enrolled 196 patients and had a randomised, double-blinded placebo-controlled design.

The LoA score, which is calculated by GlobalData’s analysis and uses a combination of machine learning and a proprietary algorithm, for aviptadil is now 43%, up from an initial 32%. An inhaled form of aviptadil is being tested in a Phase II/III study to treat moderate-to-severe Covid-19, while a yet-to-start investigator-led Phase I study to test this formulation as preventive measure is also listed on  NeuroRx is also working with the National Institutes of Health (NIH) for aviptadil’s inclusion in the adaptive Phase II I-SPY2 study for critically ill Covid-19 patients.

Relief’s market cap is $1bn (CHF 944.7m).