Kymera’s oral “Dupixent-in-a-pill” KT-621 shows strong early eczema results
Kymera Therapeutics reported positive results from its Phase 1b BroADen trial of KT-621, a first-in-class oral STAT6 degrader, in patients with moderate-to-severe atopic dermatitis (eczema).12
In the 22‑patient Phase 1b study, 4 weeks of once-daily KT-621 led to a mean 63% reduction in Eczema Area and Severity Index (EASI) scores, slightly exceeding prior Wall Street expectations for the readout.12
Both tested doses, 100 mg and 200 mg, produced similar EASI improvements (62% and 63% reductions, respectively), with measurable clinical benefit seen as early as Day 8.2
KT-621 showed deep STAT6 degradation in skin, with median reductions of 94% and 98% at 100 mg and 200 mg, respectively, supporting on-target activity for this protein degrader approach.2
Biomarker responses, including reductions in TARC and other Type 2 inflammation–related genes (e.g., PARC, Eotaxin-3, periostin, keratin 16, TSLP), were described as comparable to published dupilumab (Dupixent) data at week 4.2
Among patients with baseline TARC levels similar to those in dupilumab eczema trials (≥1,600 pg/mL), KT-621 achieved a 74% median TARC reduction by Day 29, in line with dupilumab’s 4‑week data.2
Across clinical endpoints (EASI, itch scores, SCORAD, quality-of-life measures), KT-621’s 4‑week performance was in line with or in some cases numerically exceeded published Dupixent week‑4 data, fueling its reputation as a potential “Dupixent-in-a-pill.”12
Itch and sleep disturbance improved meaningfully:
peak pruritus scores fell by about 40% overall, and SCORAD sleeplessness scores declined by around 76% at Day 29 across doses.2
Patient‑reported outcomes, including DLQI and POEM, improved steadily over the 4‑week treatment period, indicating tangible quality-of-life benefits alongside objective skin improvements.2
In patients with comorbid asthma, KT-621 reduced FeNO by 56% and improved ACQ-5 by −1.2 points (a 100% responder rate using the ≥0.5‑point threshold), hinting at broader utility in Type 2 inflammatory diseases beyond eczema.2
Earlier Phase 1 healthy-volunteer data showed near-complete STAT6 degradation at all dose levels with a safety profile “undifferentiated from placebo,” and no serious adverse events, supporting ongoing dose escalation and patient trials.34
Based on the accumulating data, Kymera has positioned KT-621 as a potential oral alternative or complement to injectable Dupixent, and plans a Phase 2b trial in atopic dermatitis followed by a mid-stage asthma study.13
Sources:
1. https://www.statnews.com/2025/12/08/kymera-kt-621-clinical-trial-results-atopic-dermatitis-challenge-dupixent/
2. https://finviz.com/news/248084/kymera-therapeutics-announces-positive-results-from-broaden-phase-1b-clinical-trial-of-kt-621-a-first-in-class-oral-stat6-degrader-in-patients-with-moderate-to-severe-atopic-dermatitis
3. https://www.biopharmadive.com/news/kymera-phase-1-study-results-stat6-protein-degrader/749579/
4. https://www.withpower.com/trial/phase-2-dermatitis-atopic-10-2025-2882e