Data from Phase 2b Studies for Rezpegaldesleukin Accepted for Two Oral Presentations at the 2026 American Academy of Dermatology Annual Meeting

SAN FRANCISCO, March 20, 2026 /PRNewswire/ -- Nektar Therapeutics (Nasdaq: NKTR) announced today that data from the ongoing Phase 2b studies of rezpegaldesleukin in atopic dermatitis and alopecia areata have been accepted for two oral presentations at the 2026 American Academy of Dermatology (AAD) Annual Meeting taking place March 27-31, 2026, in Denver, CO.

Rezpegaldesleukin is a novel first-in-class regulatory T (Treg) cell stimulator designed to address the imbalance in the immune system underlying autoimmune disorders and chronic inflammatory conditions. Rezpegaldesleukin works by targeting the IL-2 receptor complex and preferentially stimulating the proliferation of Treg cells without stimulating cytotoxic CD8+ T and CD4+ T cells, which drive autoimmune disease, to restore immune balance.

"Novel Regulatory T-cell enhancing Biologic Rezpegaldesleukin: Phase 2b Efficacy and Safety Results Following 36-Weeks of Therapy in Severe-to-Very-Severe Alopecia Areata"

• Presenter: David Rosmarin, MD, FAAD
• Presentation Date and Time: Saturday, March 28, 2026 from 10:36-10:48 AM MST
• Session Title: Late-Breaking Research: Session 1
• Location: Colorado Convention Center, Bellco Theatre 3

"Novel Regulatory T-cell enhancing Biologic Rezpegaldesleukin: Phase 2b Efficacy, Safety, and Baseline Severity–Dependent Treatment Response in Moderate-to-Severe Atopic Dermatitis"

• Presenter: Raj Chovatiya, MD, PhD, MSCI, FAAD
• Presentation Date and Time: Saturday, March 28, 2026 from 11:40 AM-11:45 AM MST
• Location: Colorado Convention Center, Lobby C, Poster Center 1

The REZOLVE-AA (NCT06340360) study enrolled patients with severe-to-very-severe alopecia areata who have not previously been treated with a JAK inhibitor or other biologic. Patients were randomized across two different dose regimens of rezpegaldesleukin or placebo. The trial completed enrollment in February 2025, with patients enrolled across approximately 30 sites globally, with 62% of patients in Poland; 24% in Canada; and 14% in the United States.

The primary endpoint was the mean percentage reduction from baseline in the Severity of Alopecia Tool (SALT) score at Week 36. Key secondary endpoints include the proportion of patients that achieved absolute SALT scores of less than or equal to 30, 20, and 10, along with the exploratory endpoint of the Clinical-Reported Outcomes (ClinRO) Eyebrow and Eyelash Score.

Enrollment criteria in the study included a diagnosis of severe-to-very-severe alopecia areata (≥ 50% scalp involvement) as measured using the SALT score at both screening and randomization. Patients who experienced an unstable course of alopecia areata over the last 6 months per investigator assessment or had inadequate washout of prior alopecia areata treatments (within 8 weeks) were excluded from the study. Patients with diffuse alopecia and other forms of alopecia were also excluded. Patient randomization was stratified based on baseline disease severity as measured by a SALT score of ≥50 or less than 95% (severe) and ≥95 (very severe). Enrollment of very severe patients was capped at 25%.

The global 393-patient Phase 2b study was conducted in patients with moderate to severe atopic dermatitis. Patients were randomized (3:3:3:2) to receive subcutaneous treatment with three doses of rezpegaldesleukin: a high dose of 24 µg/kg every two weeks (Q2W), a middle dose of 18 µg/kg every two weeks (Q2W), and a low dose of 24 µg/kg every four weeks (Q4W), or placebo Q2W. The primary endpoint and secondary endpoints were assessed at Week 16. Following the induction period, rezpegaldesleukin-treated patients who achieved EASI percent reductions of at least 50 were re-randomized (1:1) to continue at the same dose level on a Q4W or Q12W regimen through Week 52 in a blinded maintenance period. Placebo patients with EASI percent score reductions of at least 50 continue to receive placebo Q4W.

The REZOLVE-AD trial was initiated in October 2023 and enrolled patients across approximately 110 sites globally. Enrollment included 68% of patients treated in Europe, 16% in the United States, 11% in Canada, and 5% in Australia. Key eligibility criteria included a minimum EASI score of 16.0, Body Surface Area (BSA) involvement of at least 10%, and a vIGA-AD score of at least 3 at screening and randomization.

Autoimmune and inflammatory diseases cause the immune system to mistakenly attack and damage healthy cells in a person's body. A failure of the body's self-tolerance mechanisms enables the formation of the pathogenic T lymphocytes that conduct this attack. Rezpegaldesleukin is a potential first-in-class resolution therapeutic that may address this underlying immune system imbalance in people with many autoimmune and inflammatory conditions. It targets the interleukin-2 receptor complex in the body to stimulate proliferation of immune-modulating cells known as regulatory T cells. By activating these cells, rezpegaldesleukin may act to bring the immune system back into balance.

In February 2025, the U.S. Food and Drug Administration (FDA) granted Fast Track designation for rezpegaldesleukin for the treatment of adult and pediatric patients 12 years of age and older with moderate-to-severe atopic dermatitis whose disease is not adequately controlled with topical prescription therapies or when those therapies are not advisable. In July 2025, the FDA granted Fast Track designation for rezpegaldesleukin for the treatment of severe alopecia areata (AA) in adults and pediatric patients 12 years of age and older who weigh at least 40 kg.

Rezpegaldesleukin is being developed as a self-administered injection for a number of autoimmune and inflammatory diseases. It is wholly owned by Nektar Therapeutics.

 

Nektar Therapeutics is a clinical-stage biotechnology company focused on developing treatments that address the underlying immunological dysfunction in autoimmune and chronic inflammatory diseases. Nektar's lead product candidate, rezpegaldesleukin (REZPEG, or NKTR-358), is a novel, first-in-class regulatory T cell stimulator being evaluated in one Phase 2b clinical trial in atopic dermatitis, one Phase 2b clinical trial in alopecia areata, and one Phase 2 clinical trial in Type 1 diabetes mellitus. Nektar's pipeline also includes a preclinical bivalent tumor necrosis factor receptor type II (TNFR2) antibody and bispecific programs, NKTR-0165 and NKTR-0166, and a modified hematopoietic colony stimulating factor (CSF) protein, NKTR-422.

Nektar is headquartered in San Francisco, California.

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