Apogee Therapeutics (NASDAQ:APGE) outlined new 52-week maintenance data from its Phase II APECS Part A study of zumilokibart (Zumi), an optimized IL-13 antibody being developed for moderate-to-severe atopic dermatitis (AD). Executives and clinical leaders emphasized the potential for less-frequent maintenance dosing—every three months or every six months—while maintaining response and showing what the company described as deepening efficacy over time.
Company frames AD market opportunity and dosing differentiation
CEO Michael Henderson said Apogee was founded to “transform standard of care” in atopic dermatitis and type 2 inflammation, calling AD the “fastest-growing” inflammation and immunology market and projecting it could exceed $50 billion. Henderson positioned zumilokibart’s maintenance schedule as a key differentiator versus currently available biologics, which are typically dosed every two to four weeks, and said the company believes Zumi could become “potentially the first-ever six-month dose drug in dermatology.”
APECS Part A: maintenance outcomes and year-long efficacy trends
Chief Medical Officer Carl Dambkowski detailed the maintenance portion of the Phase II APECS Part A trial, describing it as double-blind and treatment-masked. Patients who received zumilokibart during induction were re-randomized to every-three-month or every-six-month maintenance dosing. Patients who were on placebo during induction crossed over to a zumilokibart regimen similar to the induction period.
Apogee presented three efficacy analyses, including maintenance of response among week 16 responders, outcomes across the full 52-week period for all patients treated with zumilokibart from induction (including week 16 non-responders), and results in placebo-to-zumilokibart crossover patients.
Key maintenance findings at week 52 for patients who were responders at week 16 included:
- EASI-75 maintenance: 85% with every-six-month dosing and 75% with every-three-month dosing.
- IGA 0/1 maintenance: 78% with every-six-month dosing and 86% with every-three-month dosing.
Among week 16 EASI-75 responders, Apogee reported percent change from baseline improvements at later timepoints, including an 88% reduction in EASI at week 52 with every-six-month dosing and 82% with every-three-month dosing. For itch, the company reported itch NRS reductions from baseline at week 48 of 67% with every-six-month dosing and 77% with every-three-month dosing.
For all patients treated from induction through one year, Dambkowski said the trial design allowed a view into whether responses plateau. He contrasted the approach with studies where only responders continue blinded therapy, and discussed mechanistic differences between IL-13 targeting and IL-4 receptor alpha blockade. Apogee highlighted year-long improvements from week 16 to week 52 across endpoints. The company reported IGA 0/1 increased from 37% at week 16 to 52% (every-six-month dosing) and 72% (every-three-month dosing) at week 52, along with increases in EASI-75, EASI-90, and EASI-100 response rates over time.
Safety profile: conjunctivitis and other common adverse events
Apogee said zumilokibart was well tolerated through 52 weeks with a safety profile “generally consistent” with the induction period and aligned with expectations for the IL-13 class. Adverse events reported in 5% or more of patients included non-infective conjunctivitis, upper respiratory tract infection, nasopharyngitis, and atopic dermatitis.
When pooling conjunctivitis terms, Apogee reported a 20.2% rate over 52 weeks with less than 1% discontinuations. Dambkowski said anti-drug antibodies (ADAs) did not impact pharmacokinetics, efficacy, or safety. During Q&A, management said new non-infective conjunctivitis cases were primarily in patients who crossed over from placebo to active drug, and that rates appeared similar across dosing arms.
Dambkowski added detail on duration and timing: median conjunctivitis duration was 27.5 days, more than 85% of cases resolved within 90 days, and most cases occurred in the first 12 weeks with a decline thereafter. He also said Apogee saw no relationship between exposure and conjunctivitis rate or duration.
Physician perspective: unmet need and adoption dynamics
Dr. Ruth Ann Vleugels of Brigham and Women’s Hospital and Harvard Medical School discussed AD’s quality-of-life burden, including sleep disruption, missed school and work, mood disorders, and healthcare utilization. She outlined limitations of systemic corticosteroids and topical therapies, and reviewed the current systemic landscape: IL-4/IL-13-pathway biologics that require injections every two to four weeks, an anti-IL-31 option that targets itch with limited rash improvement and every-four-week dosing, and oral JAK inhibitors with boxed warnings that can restrict use.
Vleugels said reduced injection frequency could be meaningful both for initiating biologic therapy and for persistence on treatment. Asked about how she would use Zumi, she said she would offer it broadly to treatment-naive patients “if it were available today,” citing a biologic-like safety profile and the dosing schedule. She also said, based on experience in dermatology, a substantial proportion of patients may switch therapies when injection frequency is meaningfully reduced, estimating around 80% in her practice when the “delta” is large.
On selecting maintenance schedules, Vleugels suggested many patients would start on every-three-month dosing, with some transitioning to every-six-month dosing as disease control allows, while emphasizing the value of having both options available.
Program outlook: Part B, Phase III plans, and other indications
Apogee said APECS is a two-part Phase II program, with Part A serving as proof-of-concept and Part B designed as a placebo-controlled dose-optimization study. The company said it increased Part B enrollment and completed enrollment ahead of schedule. Management stated it expects to report Part B 16-week results in the second quarter of 2026, which it expects to inform Phase III dose selection and support trial initiation later this year. The company also reiterated a planned 2029 launch in atopic dermatitis if approved.
Beyond AD, Apogee referenced previously disclosed positive Phase 1b asthma data showing “deep and sustained” suppression of FeNO, and said it plans to provide an update later this year on its ASPIRE asthma and ELEVATE eosinophilic esophagitis trials. During Q&A, management also discussed ongoing plans to evaluate comorbid asthma in AD populations, noting enthusiasm based on the durability of FeNO reductions in the earlier study.
Henderson closed by reiterating Apogee’s view that Zumi could offer a combination of lesion control, itch relief, and reduced injection burden—potentially as few as 2–4 maintenance dosing days per year—while the company prepares for upcoming conference presentations, including a late-breaker at the American Academy of Dermatology meeting.
About Apogee Therapeutics (NASDAQ:APGE)
Apogee Therapeutics, Inc is a clinical-stage biotechnology company dedicated to the discovery and development of novel small molecule therapeutics that selectively target the nuclear receptor RORγt, a master regulator of T cell-driven inflammatory pathways. By modulating RORγt activity, Apogee aims to offer an oral treatment option for patients with autoimmune and inflammatory skin disorders.
The company’s lead candidate, APG-157, is an oral RORγt inverse agonist currently undergoing early-stage clinical evaluation for moderate to severe plaque psoriasis.
