Leniolisib

September 22, 2026: Pharming (NASDAQ: PHAR) announced positive topline Phase II data for leniolisib in genetically identifiable primary immunodeficiencies with immune dysregulation linked to PI3Kδ signaling, with a late-breaking abstract accepted for presentation at the ESID 2026 meeting on October 14-17.

The single-arm, open-label, intra-patient dose-escalation Phase II study enrolled 13 subjects and evaluated safety, tolerability, PK/PD, and efficacy. Pharming said leniolisib was generally well tolerated, with no new safety signals; infections were the most common events. Reported clinical improvements included reduced lymphoproliferative disease, with mean spleen volume reduction of 26.4% and reductions in index lesion size.

Separately, 9 of the 13 enrolled patients also had common variable immunodeficiency (CVID). Pharming expects topline Phase II results in CVID patients with immune dysregulation, with or without an identified genetic cause, in Q4 2026. The company said those results will help inform plans for a potential registrational study in the broader CVID population.

Additional data from the PID study will be presented at ESID 2026.