Apogee's Zumilokibart Shows Promising Results in Phase 1b Asthma Trial with Durable Biomarker Suppression
Key Insights
Apogee Therapeutics reported positive interim results from a Phase 1b trial of zumilokibart (search) (APG777) in 19 patients with mild-to-moderate asthma, demonstrating a 60% reduction in FeNO levels and durable suppression through 32 weeks.
The anti-IL-13 (search) antibody showed a favorable safety profile with no serious adverse events, conjunctivitis, or injection site reactions, supporting potential for extended 3- to 6-month dosing intervals.
The company plans to advance zumilokibart (search) in the ASPIRE asthma trial while continuing Phase 2 development in atopic dermatitis, with Phase 3 initiation expected by end of 2026.
Apogee Therapeutics announced positive interim results from its Phase 1b trial of zumilokibart (search) (APG777), a novel half-life extended anti-IL-13 (search) antibody, in patients with mild-to-moderate asthma. The double-blind, placebo-controlled study evaluated 19 adult patients with elevated fractional exhaled nitric oxide (FeNO) levels, representing an enriched Type 2 inflammation population.
Trial Design and Patient Population
The Phase 1b trial enrolled adult patients with mild-to-moderate asthma and FeNO baseline levels greater than or equal to 25 parts per billion (ppb), which represents an enriched Type 2 inflammation population. Participants received a single 720 mg dose of zumilokibart (search) or placebo on day 1, with the primary focus on evaluating safety, tolerability, and FeNO suppression as a key biomarker of Type 2 inflammation.
Safety and Efficacy Results
Zumilokibart (search) demonstrated a favorable safety profile with no Grade 3 or higher treatment-emergent adverse events (TEAEs) or serious adverse events reported. The only TEAE observed in more than one patient was gastroesophageal reflux disease, affecting two patients. Notably, no conjunctivitis, injection site reactions, or anti-drug antibodies were observed.
The drug showed robust and durable suppression of FeNO, achieving a maximum absolute mean reduction of 45 ppb, representing a 60% decrease from baseline after a single dose. This suppression was maintained through 16 weeks for all patients, with suppression continuing through 32 weeks for patients with available follow-up data, supporting the potential for 3- or 6-month dosing intervals.
Positive trends were also observed in forced expiratory volume in one second (FEV1), a pharmacodynamic measure of lung function, and across Type 2 biomarkers for all available data.
Clinical Significance and Expert Commentary
"This first dataset of zumilokibart (search) in asthma is very promising and showcases the potential of this treatment to help a new patient population," said Mario Castro, M.D., M.P.H., Chief of Pulmonary, Critical Care, and Sleep Medicine at the University of Kansas. "We need new treatment options for these patients, especially those that are more convenient with the less frequent administration. These data, in particular the deep and durable FeNO suppression, highlight the promise of this drug for asthma patients with Type 2 inflammation."
Carl Dambkowski, M.D., Chief Medical Officer of Apogee, emphasized the versatility of zumilokibart (search) across Type 2 inflammatory diseases, noting that the results "further emphasize the versatility of zumilokibart across Type 2 inflammatory diseases, now spanning both dermatology and respiratory indications."
Pipeline Expansion and Development Strategy
The positive asthma results support zumilokibart (search)'s "pipeline-in-a-product" potential across inflammatory and immunology indications. In patients from the APEX Phase 2 Part A trial with comorbid asthma or sinusitis, improvements were observed in asthma and sinusitis as measured by improvements in ACQ-5 and SNOT-22, respectively.
Apogee plans to advance zumilokibart (search) in the ASPIRE asthma trial while continuing development in atopic dermatitis through the Phase 2 APEX trials. The company expects Phase 2 APEX Part A (52-week) maintenance data readout in Q1 2026 and Phase 2 APEX Part B (16-week) induction data readout in Q2 2026, with Phase 3 initiation expected in the second half of 2026.
Financial Position and Future Outlook
As of September 30, 2025, Apogee maintained a strong cash position of $913 million, including proceeds from an October 2025 equity financing, providing runway into the second half of 2028. This financial strength supports the company's advancement toward a potential 2029 launch of zumilokibart (search).
"2025 was a foundational year for Apogee, setting the stage for a potentially transformational 2026 as we plan to deliver multiple significant clinical data readouts for our monotherapy and combination programs and enter Phase 3 development," said Michael Henderson, M.D., Chief Executive Officer of Apogee.
The company is also advancing APG279 (search), a first-in-class fixed dose combination targeting both IL-13 (search) and OX40L (search), with a Phase 1b head-to-head trial against DUPIXENT in moderate-to-severe atopic dermatitis expected to read out in the second half of 2026.