Phase 3 Trial of Nemolizumab in Patients with Prurigo Nodularis

N Engl J Med. 2023 Oct 26;389(17):1579-1589. doi: 10.1056/NEJMoa2301333.


Background: Prurigo nodularis is a chronic, debilitating, and severely pruritic neuroimmunologic skin disease. Nemolizumab, an interleukin-31 receptor alpha antagonist, down-regulates key pathways in the pathogenesis of prurigo nodularis.

Methods: In this phase 3, double-blind, multicenter, randomized trial, we assigned adults with moderate-to-severe prurigo nodularis to receive an initial 60-mg dose of nemolizumab followed by subcutaneous injections of 30 mg or 60 mg (depending on baseline weight) every 4 weeks for 16 weeks or matching placebo. The primary end points were an itch response (a reduction of ≥4 points on the Peak Pruritus Numerical Rating Scale [PP-NRS; scores range from 0 to 10, with higher scores indicating more severe itch]) and an Investigator's Global Assessment (IGA) response (a score of 0 [clear] or 1 [almost clear] on the IGA [scores range from 0 to 4] and a reduction from baseline to week 16 of ≥2 points). There were five key secondary end points.

Results: A total of 274 patients underwent randomization; 183 were assigned to the nemolizumab group, and 91 to the placebo group. Treatment efficacy was shown with respect to both primary end points at week 16; a greater percentage of patients in the nemolizumab group than in the placebo group had an itch response (56.3% vs. 20.9%; strata-adjusted difference, 37.4 percentage points; 95% confidence interval [CI], 26.3 to 48.5), and a greater percentage in the nemolizumab group had an IGA response (37.7% vs. 11.0%; strata-adjusted difference, 28.5 percentage points; 95% CI, 18.8 to 38.2) (P<0.001 for both comparisons). Benefits were observed for the five key secondary end points: itch response at week 4 (41.0% vs. 7.7%), PP-NRS score of less than 2 at week 4 (19.7% vs. 2.2%) and week 16 (35.0% vs. 7.7%), and an improvement of 4 or more points on the sleep disturbance numerical rating scale (range, 0 [no sleep loss] to 10 [unable to sleep at all]) at week 4 (37.2% vs. 9.9%) and week 16 (51.9% vs. 20.9%) (P<0.001 for all comparisons). The most common individual adverse events were headache (6.6% vs. 4.4%) and atopic dermatitis (5.5% vs. 0%).

Conclusions: Nemolizumab monotherapy significantly reduced the signs and symptoms of prurigo nodularis. (Funded by Galderma; number, NCT04501679; EudraCT number, 2019-004789-17.).

Publication types

  • Randomized Controlled Trial
  • Multicenter Study
  • Clinical Trial, Phase III

MeSH terms

  • Adult
  • Antibodies, Monoclonal, Humanized* / administration & dosage
  • Antibodies, Monoclonal, Humanized* / adverse effects
  • Antibodies, Monoclonal, Humanized* / therapeutic use
  • Dermatitis, Atopic / chemically induced
  • Dermatitis, Atopic / etiology
  • Double-Blind Method
  • Humans
  • Prurigo* / complications
  • Prurigo* / drug therapy
  • Pruritus / drug therapy
  • Pruritus / etiology
  • Receptors, Interleukin* / antagonists & inhibitors
  • Severity of Illness Index
  • Treatment Outcome


  • nemolizumab
  • IL31RA protein, human
  • Receptors, Interleukin
  • Antibodies, Monoclonal, Humanized

Associated data

  • EudraCT/2019-004789-17