InventisBio Co., Ltd. announced that its JH2 selective TYK2 inhibitor nomelcitinib (D-2570) has met both the primary endpoint and the key secondary endpoint in a registrational Phase III clinical trial for the treatment of moderate-to-severe plaque psoriasis, demonstrating clinically and statistically significant superiority over placebo. This result marks a milestone in the clinical development of nomelcitinib in the field of psoriasis.

The study is a multicenter, randomized, double-blind, placebo-controlled Phase III trial designed to confirm the efficacy and safety of nomelcitinib in patients with moderate-to-severe plaque psoriasis. A total of 391 patients have been enrolled and randomly assigned in a 1:1:1 ratio to two nomelcitinib treatment groups or a placebo group. The primary endpoint is the percentage of patients achieving at least a 90% improvement from baseline in PASI (Psoriasis Area Severity Index) score (PASI 90) at week 16. The key secondary endpoint is the percentage of patients achieving PGA (Physician Global Assessment) score of 0 (skin lesion cleared) or 1 (skin lesion almost cleared) with a reduction of ≥2 points from baseline (PGA 0/1) at week 16.

At week 16, both nomelcitinib treatment groups achieved PASI 90 in over 70% of patients, significantly higher than the placebo group (p<0.0001). The proportion of patients reaching PGA 0/1 in the nomelcitinib groups exceeded 80%, also significantly higher than that in the placebo group (p<0.0001). In analyses of other secondary efficacy endpoints, the nomelcitinib groups consistently outperformed the placebo group, showing both clinically meaningful and statistically significant improvements. Among patients with moderate-to-severe plaque psoriasis, nomelcitinib demonstrated rapid onset of action — by week 4, both treatment groups already showed significantly higher proportions of patients achieving PASI 90 and PGA 0/1 compared to placebo, with further improvement observed as treatment continued.

During the study period, nomelcitinib demonstrated a favorable safety profile and good tolerability, consistent with findings from its earlier Phase II study and other JH2 selective TYK2 inhibitors, with no new safety signals identified.

"We are very excited about the topline results of this registrational phase III study. This study confirmed the magnitude of improvement in PASI 90 and PGA 0/1 seen in our earlier Phase II study, while all other secondary efficacy endpoints maintained significant improvement over the placebo group. Importantly, the safety profile is matching that of our Phase II study with no new safety signals." said Ling Zhang, CMO of InventisBio.

In addition to this registrational Phase III trial, another head-to-head Phase III clinical trial evaluating nomelcitinib for psoriasis is progressing smoothly. This trial uses deucravacitinib as the active control, and is expected to provide additional data supporting the efficacy and safety of nomelcitinib in patients with moderate-to-severe plaque psoriasis. In parallel, a Phase II study in the U.S. for psoriasis and multiple Phase II studies in China for other indications, including ulcerative colitis (UC), psoriatic arthritis (PsA), systemic lupus erythematosus (SLE), and vitiligo, are also underway.