Nektar Completes Enrollment for Phase 2b Rezpegaldesleukin Trial in Atopic Dermatitis

Nektar Therapeutics has announced the completion of target enrollment for its REZOLVE-AD Phase 2b study, focusing on the use of rezpegaldesleukin in treating moderate-to-severe atopic dermatitis. The completion of enrollment marks a significant milestone in the study, which aims to evaluate this innovative treatment's efficacy and safety.

Rezpegaldesleukin is a pioneering interleukin-2 receptor (IL-2R) agonist designed to stimulate the growth and activation of regulatory T cells (Tregs). These cells play a critical role in controlling immune responses. The treatment has shown promising results in multiple clinical trials, demonstrating a dose-dependent increase in Tregs and delivering rapid, measurable improvements in patients with moderate-to-severe atopic dermatitis. These improvements were observed to last for at least 36 weeks after the termination of treatment, showcasing the drug's potential in addressing this challenging skin condition.

Nektar Therapeutics' President and CEO, Howard W. Robin, expressed gratitude towards the patients and physicians involved in the trial, emphasizing the innovative mechanism of rezpegaldesleukin as a driving factor for the study's swift enrollment. Robin also highlighted the significant unmet need among the 30 million patients with atopic dermatitis in the U.S. and Europe, as less than 10% currently receive biologic treatments. The company plans to release the topline data from the 16-week induction period in the second quarter of 2025.

The REZOLVE-AD study involved 396 patients with moderate-to-severe atopic dermatitis who had not previously received biologic or JAK inhibitor therapies. Participants were divided into groups receiving one of three different doses of rezpegaldesleukin or a placebo for an initial 16-week induction treatment. Patients meeting the Eczema Area and Severity Index (EASI) threshold were then re-randomized to receive maintenance therapy at their original dose, either monthly or quarterly.

The primary objective of the Phase 2b study is to assess the mean improvement in the EASI score at the end of the induction period. Secondary objectives include evaluating the proportion of patients achieving a Validated Investigator Global Assessment (vIGA-AD) score of 0 or 1, those reaching at least a 75% improvement in EASI score, and those experiencing a four-point or greater reduction in the Itch Numeric Rating Scale (NRS).

Initiated in October 2023, the trial recruited patients from around 110 global sites, with 67% from European countries, 17% from the United States, 11% from Canada, and 5% from Australia. The study stratified patient randomization based on disease severity and geographic region. Inclusion criteria required a minimum EASI score of 16.0, a Body Surface Area (BSA) of at least 10%, and a minimum vIGA-AD score of 3. Patients with unstable atopic dermatitis during the screening or randomization phases were excluded.

Rezpegaldesleukin is positioned as a potential first-in-class treatment targeting the interleukin-2 receptor complex to regulate immune system balance, offering a novel approach for autoimmune and inflammatory diseases. In addition to the REZOLVE-AD study, it is under evaluation in the REZOLVE-AA study for alopecia areata.

Atopic dermatitis, the most prevalent form of eczema, affects approximately 30 million people in the U.S. It is characterized by a compromised skin barrier leading to allergic reactions and inflammation.

Nektar Therapeutics, based in San Francisco, focuses on developing treatments for autoimmune and chronic inflammatory diseases. Alongside rezpegaldesleukin, Nektar is advancing several other drug candidates aimed at addressing various immune-related conditions.