The review mapped the global dengue treatment pipeline and named only six candidates with sufficient efficacy data to be included. Resomelagon, a once-daily oral pro-resolution therapy, is the only host-directed therapy on the list, alongside several small-molecule antiviral and monoclonal antibody programs. According to SynAct, this gives it a differentiated position, since antivirals must be given early in the disease to have the best effect.

The Nasdaq Stockholm-listed company is currently running the Phase 2 study RESOVIR-2 in dengue patients, with reduced symptom duration as the primary endpoint. SynAct says this matches the WHO’s view of symptom resolution as a meaningful endpoint for treatments of non-severe dengue. Results from Part 1 are expected in 2026, pending feedback from regulatory authorities.

The WHO reported more than 14 million dengue cases in 2024, the highest number on record. Dengue is now endemic in more than 100 countries, with nearly half the world’s population at risk, and the lack of dengue-specific treatments remains a major unmet medical need.

“Being identified in this WHO-led global review provides important external validation of the potential of resomelagon in dengue worldwide,” says Thomas Jonassen, Chief Scientific Officer at SynAct.

Chief Business Officer Mads Bjerregaard says the company’s collaboration with the Brazilian company Hipolabor is a first step toward setting up the right partnerships for global development and commercialization.