Nektar Therapeutics (NKTR) investor relations material

Study design and objectives

• Phase II-B/2b REZOLVE-AA trial evaluated REZPEG/rezpegaldesleukin in 92 adults with severe-to-very-severe alopecia areata, using subcutaneous dosing every two weeks at 24 or 18 mcg/kg, or placebo, over a 36-week induction and 16-week extension, with a 24-week off-drug observation period.

• Primary endpoint was mean percent reduction in SALT score at week 36; key secondary and exploratory endpoints included deeper hair regrowth, responder analyses, and eyebrow/eyelash regrowth.

• 92 patients were randomized (REZPEG 18 μg/kg n=37, 24 μg/kg n=35, placebo n=20), stratified by baseline SALT score; study powered for a 23% delta in primary endpoint.

• Standard eligibility criteria focused on stable disease and excluded recent-onset or recently treated patients; very severe cases capped at 25%.

• Phase 3 dose established at 24 μg/kg q2w based on efficacy and safety findings.

Patient demographics and baseline characteristics

• Median age was 39 years (range 18–69); 71% were women.

• Most patients recruited from Poland (64%), with additional sites in Canada (23%) and the USA (13%).

• Average baseline SALT score was 78.12; mean duration of current AA episode was 2.78 years.

• 73% had baseline SALT 50–95, 27% had SALT 95–100.

Efficacy results

• Both REZPEG arms more than doubled the mean percent SALT reduction at week 36 versus placebo (approx. -30% vs -6%), establishing clinical proof-of-concept.

• Excluding four patients with major eligibility violations, both doses achieved statistical significance (p=0.049 and p=0.042), with fivefold improvement over placebo.

• 42% of REZPEG-treated patients achieved ≥30% reduction in SALT, 36% achieved ≥50%, and 17% achieved ≥75%, all exceeding placebo.

• Dose response observed for SALT ≤30 (29% vs 8% placebo), SALT ≤20 (15.6%/14.8% vs 6.7%), and SALT ≤10 (11.5%/8.3% vs 0.7%).

• Eyebrow and eyelash regrowth rates were higher in REZPEG arms compared to placebo.