Switzerland-based Vaderis Therapeutics AG has initiated the global Phase III HEROIC study of engasertib (VAD044) in hereditary hemorrhagic telangiectasia (HHT), backed by an oversubscribed USD 152 million Series B financing expected to fund the company through regulatory submissions and potential US FDA approval. HHT is a rare genetic vascular disorder affecting approximately 1 in 3,800 people, with no approved therapy specifically for the disease.
The round was co-led by Life Sciences at Goldman Sachs Alternatives and TCGX, with participation from Omega Funds, EQT Life Sciences, Perceptive Advisors, and Kalehua Capital, alongside existing investors Medicxi and Droia. Vaderis said the proceeds are expected to fund operations through regulatory submissions and potential US FDA approval of engasertib. The company previously raised approximately CHF 18.1 million (USD 19 million) in a Series A in 2020, led solely by Medicxi, which funded Phase I and the Phase II INSIGHT study.
Engasertib is an investigational oral, once-daily selective allosteric inhibitor of AKT1/2, originally discovered by Almac Discovery in Belfast and exclusively licensed to Vaderis in 2020. HHT-causing mutations in ENG and ACVRL1 result in constitutive AKT overactivation in endothelial cells, driving pathological angiogenesis and the formation of fragile arteriovenous malformations. By locking AKT in its inactive conformation, engasertib targets this underlying pathophysiology rather than managing symptoms. The US FDA granted engasertib Fast Track designation for HHT in November 2024.
The Phase II INSIGHT study, which enrolled 75 adults with moderate-to-severe HHT, provided the clinical basis for Phase III development. In results published in The New England Journal of Medicine in December 2025, engasertib 40 mg reduced mean epistaxis duration by 41% and frequency by 28% after 12 weeks, versus reductions of 24% and 18%, respectively, with placebo. Benefits deepened during the open-label extension, with mean bleeding duration and frequency reduced by 66% and 55%, respectively, after 12 months of additional treatment. Engasertib was generally well tolerated, with mild-to-moderate rash and hyperglycemia among the most common adverse events.