A Phase 2b Study to Evaluate Rezpegaldesleukin (Rezpeg) in the Treatment of Severe to Very Severe Alopecia Areata in Adult Patients (Rezolve AA)

A Phase 2b, Randomized, Double-Blind, Parallel Group, Placebo-Controlled Study to Evaluate the Efficacy and Safety of Rezpegaldesleukin in the Treatment of Severe to Very Severe Alopecia Areata in Adult Patients (Rezolve AA)

This is an interventional, randomized, double blind, parallel group, placebo-controlled, Phase 2b, 3-arm study to assess the effect of pegylated-recombinant-human interleukin-2 (rezpegaldesleukin) in adult participants with severe to very severe alopecia areata.

The estimated duration includes a screening period of up to 35 days, a 36-week treatment period, an optional 16-week treatment extension period, and a 24-week follow-up period. The maximum study duration is approximately 81 weeks for all participants.

Study Overview

• Status: Active, not recruiting
• Conditions: Alopecia Areata
• Intervention / Treatment: Drug: Rezpegaldesleukin; Drug: Placebo

• Study Type: Interventional
• Enrollment (Actual): 94
• Phase: Phase 2

Contacts and Locations

Study Locations

• Canada
  • British Columbia
    • Surrey, British Columbia, Canada, V3V 0C6
      • Nektar Investigative Site
  • Ontario
    • Markham, Ontario, Canada, L3P 1X3
      • Nektar Investigative Site
    • Oakville, Ontario, Canada, L6J 7W5
      • Nektar Investigative Site
    • Richmond Hill, Ontario, Canada, L4B 1A5
      • Nektar Investigative Site
  • Quebec
    • Sherbrooke, Quebec, Canada, J1G 1X9
      • Nektar Investigative Site
• Poland
  • Lower Silesian Voivodeship
    • Wroclaw, Lower Silesian Voivodeship, Poland, 51-685
      • Nektar Investigative Site
    • Wroclaw, Lower Silesian Voivodeship, Poland, 50-450
      • Nektar Investigative Site
    • Wroclaw, Lower Silesian Voivodeship, Poland, 50-566
      • Nektar Investigative Site
  • Lubusz Voivodeship
    • Nowa Sól, Lubusz Voivodeship, Poland, 67-100
      • Nektar Investigative Site
  • Masovian Voivodeship
    • Warsaw, Masovian Voivodeship, Poland, 02-953
      • Nektar Investigative Site
    • Warsaw, Masovian Voivodeship, Poland, 02-482
      • Nektar Investigative Site
  • Pomeranian Voivodeship
    • Gdansk, Pomeranian Voivodeship, Poland, 80-546
      • Nektar Investigative Site
  • Silesian Voivodeship
    • Katowice, Silesian Voivodeship, Poland, 40-611
      • Nektar Investigative Site
    • Sosnowiec, Silesian Voivodeship, Poland, 41-200
      • Nektar Investigative Site
  • Warmian-Masurian Voivodeship
    • Olsztyn, Warmian-Masurian Voivodeship, Poland, 10-229
      • Nektar Investigative Site
  • West Pomeranian Voivodeship
    • Szczecin, West Pomeranian Voivodeship, Poland, 71-500
      • Nektar Investigative Site
• United States
  • California
    • Northridge, California, United States, 91324
      • Nektar Investigative Site
  • Georgia
    • Atlanta, Georgia, United States, 30331
      • Nektar Investigative Site
  • Illinois
    • Gurnee, Illinois, United States, 60031
      • Nektar Investigative Site
  • Indiana
    • Indianapolis, Indiana, United States, 46202
      • Nektar Investigative Site
  • Michigan
    • Clinton Township, Michigan, United States, 48038
      • Nektar Investigative Site
  • New Hampshire
    • Portsmouth, New Hampshire, United States, 03801
      • Nektar Investigative Site
  • New York
    • New York, New York, United States, 10075
      • Nektar Investigative Site
  • Pennsylvania
    • Camp Hill, Pennsylvania, United States, 17011
      • Nektar Investigative Site
  • Texas
    • Frisco, Texas, United States, 75034
      • Nektar Investigative Site
    • Pflugerville, Texas, United States, 78660
      • Nektar Investigative Site

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Adults who are at least 18 years and ≤60 years for males (≤70 years of age for females) old at the time of informed consent

• Diagnosis of Alopecia Areata (AA) severity at screening and baseline:

  1. severe to very severe AA (≥ 50% scalp involvement) as measured using the SALT score
  2. Documented history over 6 months with no spontaneous improvement prior to baseline
  3. Current episode of severe to very severe AA of less than 8 years
• Women of childbearing potential (WOCBP) must have a negative pregnancy test at screening and baseline.
• While on investigational product and for at least 30 days after taking the last dose of investigational product (IP), WOCBP who engage in activity in which conception is possible must use approved highly effective contraceptive method(s). For male patient with partner that is WOCBP in which conception is possible, male patient must agree to use approved highly effective contraceptive method(s).
• Able to complete patient questionnaires
• Able and willing to comply with requested study visits and procedures
• Able and willing to provide written informed consent
• Able to communicate, read and/or understand the local language

Exclusion Criteria:

• Men and women (of reproductive potential) unwilling to use birth control and women who are pregnant or breastfeeding.
• Patient has primarily "diffuse" type AA (characterized by diffuse hair shedding).
• Presence of another form of alopecia.

• Prior use of any of the following treatments:

  1. aldesleukin
  2. investigational IL-2 analog
  3. oral Janus kinase (JAK) inhibitor for any indication, including, but not limited to, baricitinib, upadacitinib, abrocitinib, tofacitinib, and ruxolitinib, whether marketed or investigational
  4. systemic immune-modulating biologic therapy (including, but not limited to, dupilumab, tralokinumab, lebrikizumab, nemolizumab, rocatinlimab, rituximab, ocrelizumab, ofatumumab, belimumab, daxdilimab, etc.) whether marketed or investigational
• History of cancer or lymphoproliferative disease within 5 years prior to Day 1. Note: Patients with successfully treated nonmetastatic cutaneous squamous cell or basal cell carcinoma with no evidence of metastatic disease for 3 years and/or localized carcinoma in situ of the cervix with no evidence of recurrence within the 3 years prior to Day 1 are not to be excluded.
• Current infection with human immunodeficiency virus (HIV), hepatitis B virus (HBV), or hepatitis C virus (HCV) at screening.
• Other skin conditions that would interfere with study assessments of AA

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Quadruple

Number of Arms

3

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Low Dose; Rezpegaldesleukin Low Dose Every 2 weeks	Drug: Rezpegaldesleukin; Pharmaceutical form: Injection solution Route of administration: subcutaneous; Other Names: NKTR-358; REZPEG; LY3471851 (formerly)
Experimental: High Dose; Rezpegaldesleukin High Dose Every 2 weeks	Drug: Rezpegaldesleukin; Pharmaceutical form: Injection solution Route of administration: subcutaneous; Other Names: NKTR-358; REZPEG; LY3471851 (formerly)
Placebo Comparator: Placebo; Placebo Every 2 weeks	Drug: Placebo; Pharmaceutical form: Injection solution Route of administration: subcutaneous

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Percent change from baseline in Severity of Alopecia Tool (SALT) score at Week 36	The SALT score is the sum of percentage of hair loss in all areas with a maximum score of 100 (higher score indicates greater hair loss).	Baseline and Week 36

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Percent change from baseline in SALT score	SALT score is the sum of percentage of hair loss in all areas with a maximum score of 100 (higher score indicates greater hair loss).	Baseline and Weeks 12, 16, 20, 24, 28, and 32
Proportion of patients achieving improvement in Severity of Alopecia Tool (SALT) ≥ 50%/75%/90%	Proportion of patients achieving improvement of ≥ 50%/75%/90% in Severity of Alopecia Tool (SALT) relative to their baseline score (SALT50/75/90). SALT score is the sum of percentage of hair loss in all areas with a maximum score of 100 (higher score indicates greater hair loss).	Baseline and Weeks 12, 16, 20, 24, 28, 32, and 36
Proportion of patients achieving an absolute SALT score ≤ 10/20/30/50	Proportion of patients achieving an absolute SALT score of ≤ 10/20/30/50. SALT score is the sum of percentage of hair loss in all areas (higher score indicates greater hair loss). Total percentage of patients with absolute SALT score of ≤ 10/20/30/50 will be calculated.	Baseline and Weeks 12, 16, 20, 24, 28, 32, and 36

Collaborators and Investigators

• Sponsor: Nektar Therapeutics
• Investigators: Study Director: Study Director, Nektar Therapeutics

Study record dates

Study Major Dates

• Study Start (Actual): April 2, 2024
• Primary Completion (Actual): November 26, 2025
• Study Completion (Estimated): August 1, 2026

Study Registration Dates

• First Submitted: March 25, 2024
• First Submitted That Met QC Criteria: March 25, 2024
• First Posted (Actual): April 1, 2024

Study Record Updates

• Last Update Posted (Actual): March 31, 2026
• Last Update Submitted That Met QC Criteria: March 27, 2026
• Last Verified: March 1, 2026

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Skin Diseases; Alopecia; Hypotrichosis; Hair Diseases; Skin and Connective Tissue Diseases; Alopecia Areata; Amino Acids, Peptides, and Proteins; Proteins; Hydrolases; Enzymes; Enzymes and Coenzymes; Intracellular Signaling Peptides and Proteins; Carrier Proteins; rho GTP-Binding Proteins; Monomeric GTP-Binding Proteins; GTP-Binding Proteins; GTP Phosphohydrolases; Acid Anhydride Hydrolases; rhoA GTP-Binding Protein
• Other Study ID Numbers: 23-358-06; 2023-509981-39 (EudraCT Number)

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: Yes
• Studies a U.S. FDA-regulated device product: No