Nektar Therapeutics (NKTR) Study result summary

Study design and objectives

• The 52-week phase 2b REZOLVE-AD study evaluated monthly (Q4W) and quarterly (Q12W) maintenance dosing of rezpegaldesleukin in moderate-to-severe atopic dermatitis, focusing on durability, deepening of response, and long-term safety.

• Induction used 24 μg/kg Q2W for 16–24 weeks, after which patients achieving at least EASI-50 were re-randomized to maintenance regimens.

• Key endpoints included EASI-75, EASI-90, vIGA-AD 0/1, and Itch NRS at week 52, with new and deepening responses, including EASI-100, quantified.

• Over 1,000 patients have been treated, with 381 patient-years of exposure, providing a robust safety dataset.

• Key eligibility included EASI ≥16, BSA ≥10%, and vIGA-AD ≥3 at screening and randomization.

Efficacy results and response durability

• Both Q4W and Q12W regimens showed high durability: EASI-75 maintained in 71–92% and EASI-90 in 57–81% at week 52.

• Deepening of response observed: up to 30% achieved EASI-100 at 52 weeks, with up to a five-fold increase from baseline.

• New responses were seen in non-responders at maintenance baseline, with up to 62% new EASI-75 responders in some arms.

• Efficacy was consistent across moderate and severe subgroups and in those with comorbid asthma.

• Meaningful improvements were observed in Itch NRS and vIGA-AD 0/1 endpoints.

Safety and tolerability

• Rezpegaldesleukin was well-tolerated with a favorable safety profile and no new safety concerns during maintenance.

• Discontinuation due to adverse events was low (3.5%), with most common AE being mild injection site reactions.

• No increased risk of infection, conjunctivitis, oral herpes, oral ulcers, malignancies, or serious adverse events compared to placebo.

• Lower frequency of injection site reactions observed with longer dosing intervals.

• No cases of facial swelling or other serious adverse events were observed.