Pritelivir

A privately-held German biotech said its experimental herpes drug succeeded in a Phase 3 study, setting up plans to apply for US approval in 2026. Patients on Aicuris’ drug, called pritelivir, outperformed those in a comparator arm where doctors could use a variety of treatment options. The study randomized 102 immunocompromised patients with herpes to receive either Aicuris’ drug or the investigator’s choice, according to a press release, and they were assessed on lesion healing. But Thursday’s topline readout leaves many questions unanswered about pritelivir, including how the drug fared against other efficacy and safety goals. The clinicaltrials.gov database lists 11 secondary efficacy measures and 14 secondary safety measures for the study. The company said it plans to present more detailed results at a medical conference in early 2026 as it prepares for a potential commercial launch. “We will now rapidly advance our New Drug Application submission to the FDA and we look forward to presenting a comprehensive analysis of these positive results at a medical conference next year,” Aicuris CEO Larry Edwards said in the press release. Aicuris was spun out of Bayer’s infectious disease efforts in 2006, and was founded and led by biochemist Helga Rübsamen-Schaeff until 2015. It out-licensed its first product, a drug to prevent cytomegalovirus infection called Prevymis, to Merck in 2012. Hello Jeremy Nelson , Endpoints is fielding its next Pulse Poll — a one-minute check-in on how artificial intelligence is reshaping biopharma. Results are confidential and will feed into our coverage of AI's real-world impact. Hello Jeremy Nelson , Endpoints is fielding its next Pulse Poll — a one-minute check-in on how artificial intelligence is reshaping biopharma. Results are confidential and will feed into our coverage of AI's real-world impact. Hello Jeremy Nelson , Endpoints is fielding its next Pulse Poll — a one-minute check-in on how artificial intelligence is reshaping biopharma. Results are confidential and will feed into our coverage of AI's real-world impact. Hello Jeremy Nelson , Endpoints is fielding its next Pulse Poll — a one-minute check-in on how artificial intelligence is reshaping biopharma. Results are confidential and will feed into our coverage of AI's real-world impact. Hello Jeremy Nelson , Endpoints is fielding its next Pulse Poll — a one-minute check-in on how artificial intelligence is reshaping biopharma. Results are confidential and will feed into our coverage of AI's real-world impact. Hello Jeremy Nelson , Endpoints is fielding its next Pulse Poll — a one-minute check-in on how artificial intelligence is reshaping biopharma. Results are confidential and will feed into our coverage of AI's real-world impact. Hello Jeremy Nelson , Endpoints is fielding its next Pulse Poll — a one-minute check-in on how artificial intelligence is reshaping biopharma. Results are confidential and will feed into our coverage of AI's real-world impact. Hello Jeremy Nelson , Endpoints is fielding its next Pulse Poll — a one-minute check-in on how artificial intelligence is reshaping biopharma. Results are confidential and will feed into our coverage of AI's real-world impact. If Thursday’s trial results support approval, pritelivir would be on track to be the first drug Aicuris commercializes on its own. That would also make it a rarity as a new treatment for herpes, a disease still commonly treated with drugs first approved in the 1980s and 1990s. “There has been no HSV treatment innovation for this patient group for decades and pritelivir has the potential to be life-changing,” Genovefa Papanicolaou, clinical director of infectious disease service at Memorial Sloan Kettering Cancer Center, said in a statement included in the release. In its most recent corporate deck , Aicuris estimated pritelivir’s peak potential market sales of roughly $1.4 billion to $2 billion. The slides include an approximate monthly list price of $30,000 for the US.

Aicuris is preparing an FDA filing for its helicase primase inhibitor pritelivir after the drug met the primary endpoint of a Phase III study for the treatment of immunocompromised patients with refractory herpes simplex virus (HSV), with or without resistance (R±R).  According to results, pritelivir demonstrated superior lesion healing in patients receiving treatment up to 28 days compared to those given investigator's choice of foscarnet, cidofovir, compounded topical cidofovir or imiquimod. Aicuris noted that statistical superiority in lesion healing increased in patients receiving up to 42 days of treatment. "With encouraging safety, convenient oral dosing, and the statistically superior efficacy in treating R±R HSV…pritelivir could be a paradigm shift for immunocompromised patients globally," remarked Cynthia Wat, chief medical officer at Aicuris.The PRIOH-1 study enrolled 158 immunocompromised participants, with 102 R±R HSV patients randomised to receive treatment with pritelivir or investigator's choice. Those in the pritelivir arm received a loading dose of 400 mg on the first day of treatment followed by 100 mg each subsequent day until all lesions were healed. Pritelivir's mechanism of action — through the targeting of the helicase-primase complex of HSV — does not rely on activation by viral enzymes, so it can overcome HSV infections that are resistant to treatments, Aicuris noted."We plan to rapidly advance our new drug application submission to the FDA, and we look forward to presenting a comprehensive analysis of these positive results at a medical conference next year," said CEO Larry Edwards.