Nektar Therapeutics Receives FDA Fast Track Designation for Rezpegaldesleukin in Severe-to-Very Severe Alopecia Areata

Nektar Therapeutics has received Fast Track designation from the FDA for rezpegaldesleukin, an investigational therapy targeting interleukin-2 receptor complex to stimulate regulatory T cells. The designation adds to rezpegaldesleukin's Fast Track designation in atopic dermatitis. Nektar expects to announce topline data in December from its ongoing REZOLVE-AA Phase 2b study in severe-to-very severe alopecia areata.

SAN FRANCISCO, July 2, 2025 — Nektar Therapeutics (Nasdaq: NKTR) has received Fast Track designation from the U.S. Food and Drug Administration (FDA) for rezpegaldesleukin, an investigational therapy targeting the interleukin-2 receptor complex to stimulate regulatory T cells (Tregs). This designation adds to rezpegaldesleukin's existing Fast Track designation for atopic dermatitis and is aimed at addressing the urgent medical need for novel, effective therapies in severe-to-very severe alopecia areata.

The FDA's Fast Track designation is granted to therapies that treat serious conditions and have the potential to address unmet medical needs. Rezpegaldesleukin, a potential first-in-class resolution therapeutic, targets the interleukin-2 receptor complex to stimulate the proliferation of Tregs, which act to bring the immune system back into balance. This mechanism of action could offer a novel approach to treating autoimmune and inflammatory diseases, including alopecia areata.

The REZOLVE-AA Phase 2b study, which enrolled approximately 90 patients with severe-to-very severe alopecia areata, is currently underway. The primary efficacy endpoint will evaluate the mean percent change in the Severity of Alopecia Tool (SALT) score at the end of the 36-week induction period. Secondary endpoints include the proportion of participants with a greater than or equal to 50% reduction in SALT score and other assessed timepoints, as well as the proportion of patients achieving SALT-20. The Company expects to share these results in December 2025.

Jonathan Zalevsky, Ph.D., Senior Vice President and Chief Research & Development Officer at Nektar, stated, "We are pleased that rezpegaldesleukin has been granted Fast Track designation for the treatment of alopecia areata. There is an urgent need for novel mechanistic approaches that could treat the underlying pathogenesis of this disorder. We remain on track to announce topline data in December from our ongoing REZOLVE-AA Phase 2b study for rezpegaldesleukin in alopecia areata, and we look forward to the opportunity to collaborate quickly with the agency on a potential registrational program following the completion of Phase 2."

The Fast Track designation allows for more frequent meetings and written interactions with the FDA, as well as potential eligibility for rolling review and priority review, which could expedite the regulatory review process and bring this potential new therapy to patients more quickly.

References:
[1] https://www.prnewswire.com/news-releases/nektar-therapeutics-receives-fast-track-designation-for-rezpegaldesleukin-for-the-treatment-of-severe-to-very-severe-alopecia-areata-302515436.html