Phase I data from a placebo-controlled study in healthy adults suggest that PRA-216, a bispecific antibody that simultaneously blocks IL-4Rα and TSLP, can suppress multiple Type 2 inflammatory biomarkers for at least 12 weeks from a single subcutaneous dose — a pharmacodynamic profile that, if replicated in patients, would place it above the dosing frequency of most approved biologics in asthma, chronic obstructive pulmonary disease (COPD), and atopic dermatitis.
San Diego-based Prana Therapies presented the results at the European Respiratory Society (ERS) International Congress 2026 in Barcelona. The Phase I/II trial enrolled 57 healthy adults across seven single- and multiple-ascending-dose (SAD and MAD) cohorts. In the 600 mg MAD cohort — dosed every two weeks for three doses — PRA-216 produced 100% inhibition of pSTAT6, 100% reduction in blood eosinophils, 50% reduction in serum TARC, and 25% reduction in IgE, sustained for at least 12 weeks. The drug achieved 85% subcutaneous bioavailability and was well-tolerated, with no serious adverse events, no Grade ≥3 treatment-emergent adverse events, no injection site reactions, and no reports of conjunctivitis.
PRA-216 targets both IL-4Rα, blocking the shared receptor subunit for IL-4 and IL-13 signaling, and TSLP, an upstream epithelial cytokine that initiates Type 2 inflammatory cascades. Combining these two mechanisms in a single molecule distinguishes it from the two most commercially relevant comparators: Sanofi/Regeneron's Dupixent (dupilumab), which targets IL-4Rα alone, and AstraZeneca's Tezspire (tezepelumab), which targets TSLP alone. No approved biologic currently blocks both nodes simultaneously.
Dupilumab requires every-two-week or every-four-week injections across its approved indications; tezepelumab is dosed monthly. GSK's Exdensur (depemokimab), an anti-IL-5 antibody approved in December 2025 for severe eosinophilic asthma, set a new convenience benchmark at twice-yearly dosing, but is restricted to a single indication and a single pathway. Prana's Phase I data support a potential every-12-week interval for PRA-216 across three indications simultaneously — a combination that no approved agent currently offers.