Apogee Therapeutics says APEX Part A met all primary, secondary endpoints

Apogee Therapeutics (APGE) announced 16-week data from Part A of the Phase 2 APEX clinical trial of APG777, a potential best-in-class anti-IL-13 antibody, in patients with moderate-to-severe atopic dermatitis. The Phase 2 APEX clinical trial is a randomized, placebo-controlled study evaluating APG777 in patients with moderate-to-severe AD. Part A of the trial enrolled 123 adult patients who were randomized 2:1 to APG777 versus placebo and received an induction regimen dosing of 720mg at Weeks 0 and 2, followed by 360mg at Weeks 4 and 12. Patients benefiting from treatment continued maintenance dosing, evaluating 3- or 6-month dosing of APG777. The primary endpoint of Part A is mean percentage change in Eczema Area Severity Index score from baseline at Week 16. Secondary endpoints include EASI-75, EASI-90, Validated Investigator Global Assessment 0/1 and Itch Numeric Rating Scale at Week 16. Initial 16-week findings from APEX Part A include efficacy results, which compare favorably versus standard of care across endpoints as well as rapid onset of itch relief and lesion reduction, and a favorable safety profile consistent with its class: The trial met its primary endpoint, with APG777 showing significantly greater least squares mean percent change from baseline at Week 16 with an EASI reduction of 71.0% compared to placebo of 33.8%. Highest absolute and placebo-adjusted EASI-75 of any biologic with 66.9% of participants treated with APG777 achieving EASI-75 compared to 24.6% on placebo. Pre-specified sensitivity analysis showed consistent results in both moderate and severe patients. Additionally, an exposure-response relationship was observed, with patients in the two highest quartiles of exposures achieving the highest EASI-75 response at Week 16, 83.3% for quartile three and 89.5% for quartile four. APEX Part B is testing a higher dose of APG777, which is projected to achieve average exposures in line with the highest quartile of exposures from Part A. Additional key secondaries were in line with standard of care, including vIGA 0/1 and EASI-90. vIGA 0/1 of 34.9% compared to placebo of 17.3%. EASI-90 of 33.9% compared to placebo of 14.7%. Patients in the highest quartile of exposures achieved the highest response, 63.2% vIGA 0/1 and 63.2% EASI-90 at Week 16 Treatment of patients with APG777 led to rapid onset of itch relief and achieved statistically significant reduction by Week 1. 50.7% reduction of Itch NRS from baseline compared to 23.2%. APG777 was well tolerated with a safety profile consistent with other agents in the class. Serious treatment-emergent adverse events were rare for APG777-exposed patients. Discontinuation rate due to AEs was low for APG777-exposed patients. The most common TEAEs were non-infective conjunctivitis, upper respiratory tract infection, and nasopharyngitis, the latter two numerically lower in APG777 treated patients. There were 0 injection site reactions in the APG777 group. APEX Part B is a placebo-controlled dose optimization with approximately 280 patients randomized 1:1:1:1 to high, medium, or low dose APG777 versus placebo. Part B continues to enroll participants with readout expected in mid-2026. Data readout from the maintenance phase of APEX Part A, testing 3- and 6-month maintenance dosing, is expected in the first half of 2026.