Nektar Therapeutics starts Phase III eczema program as shares gain 5.9%

Nektar Therapeutics started two Phase III studies for rezpegaldesleukin in atopic dermatitis, sending shares up 5.9%.

"The ZENITH AD program was designed from our compelling Phase IIb data," Howard W. Robin, president and chief executive officer of Nektar Therapeutics, said. "We expect initial data from ZENITH AD in mid-2028."

The ZENITH AD-1 and ZENITH AD-2 trials will each enroll 510 patients aged 12 and older who have not previously received systemic biologic or JAK inhibitor treatment. A third study, ZENITH AD-3, will enroll 510 patients with prior treatment experience and is scheduled to begin in September. The program targets 1,530 patients across North America, Europe and Asia-Pacific. The primary endpoint is IGA 0/1 response at Week 24, with EASI-75 as a key secondary measure. The studies include a 24-week blinded induction period with dosing of 24 micrograms per kilogram every two weeks, followed by a 28-week maintenance period where responders are re-randomized to monthly, quarterly or placebo dosing. About 25 percent of patients with moderate-to-severe atopic dermatitis have comorbid asthma, and the program includes a prespecified assessment of asthma control through the ACQ-5 questionnaire.

Rezpegaldesleukin is a first-in-class regulatory T-cell biologic designed to restore immune balance by selectively expanding Tregs, differentiating it from older IL-2 therapies that broadly stimulate immune cells. The Phase IIb study in 393 patients showed an up to five-fold increase in EASI-100 response between Week 16 and Week 52, supporting the durability of response. The FDA granted Fast Track designation for the atopic dermatitis program in February 2025 and for severe alopecia areata in July 2025.

Nektar also plans to initiate a single registrational Phase III trial in alopecia areata in early 2027, based on Phase IIb data from the REZOLVE-AA study showing deepening responses through 52 weeks. A Phase II study in Type 1 diabetes is ongoing, with initial data expected in 2027. The company's pipeline also includes preclinical TNFR2 antibody and bispecific programs, NKTR-0165 and NKTR-0166.

Year to date, Nektar shares have rallied 62.5 percent, compared with a 4.5 percent decline for the industry. Atopic dermatitis affects about 30 million people in the United States, representing a large market opportunity for a differentiated treatment. The company targets a biologics license application filing in 2029. Investors will watch for initial ZENITH AD data in mid-2028 and the planned alopecia areata Phase III start in early 2027.

This article is for informational purposes only and does not constitute investment advice.