Reistone Biopharma Co., Ltd, incubated by Hengrui Pharmaceuticals (SHA: 600276) with USD 100 million in 2018, has released interim data from the 16-week mark in the Phase III QUARTZ3 study. The study is assessing the efficacy of the JAK1 inhibitor ivarmacitinib in patients with moderate to severe atopic dermatitis (AD).
Study Design and Results
The randomized, double-blind, placebo-controlled, global multi-center regulatory Phase III study is designed to evaluate the drug’s efficacy and safety in moderate to severe AD patients at week 52. A total of 336 subjects were enrolled. At 16 weeks, the proportion of subjects achieving IGA 0/1 response with a decrease of ≥ 2 points from baseline (IGA response) in the 8 mg and 4 mg groups of ivarmacitinib was 42.0% and 36.3%, respectively. The proportion of subjects responding to EASI-75 was 66.1% and 54.0%, respectively, significantly higher than those in the placebo group (9.0% and 21.6%). The reduction in itching was similar in both dose groups as early as week 4 and remained consistent at week 16, with ivarmacitinib improving itching symptoms within a short period, up to 3 days after administration.
Safety Profile
In terms of safety, the overall incidence of adverse events in the two dose groups was comparable to that in the placebo group. The incidence of serious adverse events and adverse events leading to discontinuation of the study drug did not increase.
Market Potential and Context
Ivarmacitinib was awarded breakthrough therapy designation (BTD) status in China in January 2021 and is being prepared for market filing. Currently, there is no home-grown JAK1 inhibitor product in China. Pfizer’s abrocitinib and AbbVie’s upadacitinib, both oral JAK1 inhibitors, have been approved for marketing abroad and generated USD 6 million and USD 1.651 billion in global sales in 2021, respectively.-Fineline Info & Tech
