Kymera Completes BROADEN2 Enrollment for KT-621 in Atopic Dermatitis

Kymera Therapeutics recently announced it has completed enrollment in the global phase 2b BROADEN2 trial (NCT07217015) evaluating KT-621, an oral STAT6 degrader, for moderate to severe atopic dermatitis (AD). The company announced enrollment finished nearly 6 months ahead of schedule, allowing topline data to move up from a prior mid-2027 target to year-end 2026. Pending discussions with regulators, Kymera plans to initiate phase 3 AD trials by mid-2027.¹

The accelerated timeline shortens the runway between phase 2b data and a potential phase 3 program for a STAT6-directed therapy, the first of its kind to reach clinical testing.¹ KT-621 already holds FDA Fast Track designation for moderate to severe AD and eosinophilic asthma.²

BROADEN2 is a randomized, double-blind, placebo-controlled, dose-ranging trial testing 3 doses of KT-621 in approximately 200 patients ages 12 to 75 with moderate to severe AD. The trial runs 16 weeks, with the primary end point set as percent change from baseline in Eczema Area and Severity Index (EASI) score at week 16. Secondary end points will assess additional safety, efficacy, and quality-of-life measures, though results are not yet available, given that the trial has only just completed enrollment. According to Kymera, the early completion reflects strong patient and provider interest in an oral option for AD, a disease with substantial unmet need despite existing biologic and small-molecule therapies.¹

"What's important for us is number 1, to show our drug has a significant impact compared to placebo, and number 2, looking across these different doses and looking at safety and efficacy to ultimately choose 1 dose among those 3 to bring into our subsequent phase 3 study," said Jared Gollob, MD, chief medical officer at Kymera Therapeutics, in a recent interview.

KT-621 Mechanism and Broader Type 2 Inflammation Pipeline

KT-621 is designed as a once-daily oral degrader of STAT6, the transcription factor driving IL-4 and IL-13 signaling and central to Type 2 inflammation.³ In earlier phase 1 (NCT06945458) testing in patients with AD, KT-621 produced deep STAT6 degradation in blood and skin, along with reductions in Type 2 inflammatory biomarkers and improvements on clinical end points and patient-reported outcomes, according to Kymera. The company reported KT-621 was well tolerated in the phase 1 study, with a favorable safety profile, though no new safety data accompanied this enrollment announcement.³

Beyond AD, KT-621 is being evaluated in the ongoing phase 2b BREADTH trial in moderate to severe eosinophilic asthma, with data expected in late 2027.¹ Kymera has positioned STAT6 degradation as a potential approach across a broader set of Type 2 inflammatory diseases affecting more than 140 million patients worldwide, including asthma, chronic obstructive pulmonary disease, eosinophilic esophagitis, chronic rhinosinusitis with nasal polyps, chronic spontaneous urticaria, prurigo nodularis, and bullous pemphigoid.³

"Completing enrollment in BROADEN2 nearly 6 months ahead of our anticipated timeline reflects a high degree of patient and provider interest in a safe and effective oral option for atopic dermatitis, a chronic and debilitating disease," said Nello Mainolfi, PhD, founder, president, and CEO of Kymera Therapeutics, in the news release. "It's also a testament to KT-621's compelling profile across preclinical, healthy volunteer, and patient studies, and the best-in-industry execution of our team."¹

If BROADEN2 data confirm the phase 1 signal, KT-621 would represent an oral, mechanism-targeted alternative to existing injectable biologics for AD, with the accelerated phase 3 timeline potentially shortening the path to an NDA filing.¹

In his interview, Gollob pointed to a significant gap in current AD care: only approximately 15% of patients with moderate to severe AD who are eligible for biologics actually receive them, with reluctance around injectable therapy cited as a contributing factor. He framed an effective oral agent as a potential solution to low systemic therapy uptake.

"There are millions of such patients who are not taking systemic therapy just because they're hesitant to go on injectables,” Gollob said.

He said the broader goal is to reach patients who are deterred by injectables but stand to benefit meaningfully from a therapy targeting the root cause of their inflammation.

References

1. Kymera Therapeutics completes enrollment in the phase 2b BROADEN2 trial of KT-621 in atopic dermatitis with topline data by year-end 2026. News release. Kymera Therapeutics. June 25, 2026. Accessed June 25, 2026. https://investors.kymeratx.com/news-releases/news-release-details/kymera-therapeutics-completes-enrollment-phase-2b-broaden2-trial
2. Kymera Therapeutics announces U.S. FDA Fast Track Designation for KT-621, a first-in-class, oral STAT6 degrader for the treatment of moderate to severe asthma. News release. Kymera Therapeutics. April 13, 2026. Accessed June 25, 2026. https://investors.kymeratx.com/news-releases/news-release-details/kymera-therapeutics-announces-us-fda-fast-track-designation-kt-0