Apogee Therapeutics (APGE) Study result summary

Study design and objectives

• The phase II APEX Part A study was a 52-week, double-blind, placebo-controlled trial evaluating zumilokibart in adults with moderate-to-severe atopic dermatitis, focusing on maintenance and deepening of efficacy with every 3- or 6-month dosing after induction.

• Patients were re-randomized at week 16 to receive maintenance dosing every 3 months (Q3M/Q12W) or every 6 months (Q6M/Q24W); placebo patients crossed over to active treatment.

• Safety and efficacy were evaluated across all patients, regardless of initial response at week 16, and baseline demographics were consistent with AD trials.

• The study design mirrored upadacitinib phase III trials and included a dose optimization component (Part B), with results expected in Q2 2026.

• Patients crossing over from placebo to zumilokibart achieved similar efficacy by week 52.

Key efficacy results

• At week 52, zumilokibart maintained EASI-75 response in 75% (Q3M) and 85% (Q6M) of patients; IGA 0/1 was maintained in 86% (Q3M) and 78% (Q6M).

• Deepening of response was observed, with IGA 0/1 rates rising from 37% at week 16 to 52% (Q6M) and 72% (Q3M) at week 52, and EASI-75 rates increasing to 81% (Q6M) and 88% (Q3M).

• EASI-100 (clear skin) was achieved in 19% (Q6M) and 41% (Q3M) at week 52; EASI and itch NRS reductions reached up to 88% and 77%, respectively, among EASI-75 responders.

• Deepening of response was seen across all endpoints, including EASI-90 and EASI-100, with up to 36 percentage points improvement.

• Responses continued to improve over time, including in patients who did not fully respond in the first 16 weeks.

Safety and tolerability

• Zumilokibart was well tolerated over 52 weeks, with a safety profile consistent with the IL-13 class; 71.4% of patients reported at least one TEAE and 0.8% reported a serious TEAE.

• Most common adverse events were non-infective conjunctivitis (13.4–20.2%), upper respiratory tract infection (12.6%), nasopharyngitis (9.2%), and atopic dermatitis.

• Conjunctivitis occurred in 20.2% of patients, with less than 1% discontinuation; rates were similar to dupilumab and lebrikizumab.

• Most conjunctivitis cases were short-lived (median 27.5 days), resolved within 90 days, and were unrelated to drug exposure.

• No impact of anti-drug antibodies on PK, efficacy, or safety was observed.