Ivarmacitinib tablet is the first National Class A new drug for atopic dermatitis designed and developed in China.

Reistone Biopharma’s once daily Ivarmacitinib as monotherapy relieves in improving skin inflammation and itchiness n adults and adolescents with moderate-to-severe, according to a results from thePhase III QUARTZ3 study.

The study evaluated the efficacy and safety of once daily Ivarmacitinib as monotherapy in adults and adolescents with moderate-to-severe atopic dermatitis (AD). Two doses (8mg QD or 4mg QD) met the co-primary endpoints, demonstrating significantly improved IGA 0/1 response rate and EASI 75 response rate versus placebo at week 16 (P<0.001). Ivarmacitinib was well-tolerated at both doses without new safety findings.

Ivarmacitinib tablet is highly selective Janus kinase type 1 (JAK1) inhibitor developed by Reistone and Jiangsu Hengrui for oral use.  Several late-stage clinical studies are on-going with both oral and topical dosage forms for several immune-inflammatory diseases including Ulcerative Colitis, Alopecia Areata, Crohn's Disease, etc. The high selectivity of SHR0302 may potentially provide a favorable safety and efficacy profile compared to the pan-JAK inhibitors. Ivarmacitinib tablet is the first National Class A new drug for atopic dermatitis designed and developed in China. In January 2021, based on its Phase II results in the patients of atopic dermatitis, Ivarmacitinib was designated as Breakthrough Therapeutic Drug (BTD) by the Center for Drug Evaluation (CDE) of the National Medical Products Administration (NMPA). Ivarmacitinib is the first domestically developed JAK1 inhibitor to successfully achieve a pivotal phase 3 study in atopic dermatitis.

Reistone Biopharma plans to communicate with the national regulatory authority about the new drug marketing application (NDA) as soon as possible. Ivarmacitinib is expected to be marketed first in China, providing an innovative drug choice for the Chinese patients with atopic dermatitis.

About the study

QUARTZ3 (NCT04875169) was a randomized, double-blinded, placebo-controlled study conducted at 15 research centers in Canada and 36 in China, evaluating the efficacy, safety, and tolerability of Ivarmacitinib in adult and adolescent subjects with moderate-to-severe Atopic Dermatitis. A total number of 336 subjects were randomized into two oral doses of Ivarmacitinib (8 mg or 4 mg) or placebo at a ratio of 1:1:1 and treated for up to 52 weeks. At week 16, subjects from the Placebo group were re-randomized into two active groups. The co-primary endpoints were defined as the percentage of subjects achieving IGA 0/1 response and the percentage of subjects achieving EASI 75 response at week 16. Based on the study hypothesis, the trial is considered to have reached the efficacy endpoint only if both IGA and EASI-75 response rates were statistical significantly higher in the active drug group compared to the placebo group. In addition to IGA and EASI, QUARTZ3 set several secondary study endpoints, including the proportion of participants with the most severe pruritus index improvement of 4 points or more, EASI-50/EASI-90 response rate, SCORAD-50/75/90 response rate, and patient-reported outcomes, POEM and DLQI/CDLQI.

"We were honored to lead the Phase II and Phase III clinical studies of Ivarmacitinib in patients with atopic dermatitis. From the first patient enrolled in Phase II in 2019 to the completion of Phase III study in 2022, it took more than 3 years, especially the Phase III study, when the impact of COVID-19 was at its peak. Organizing and conducting such a high-level international multicenter clinical trial is not easy", says Professor Zhang Jianzhong, Principal Investigators of this study, Director of Dermatology, Peking University People's Hospital, in a news release. "Today, the phase III top-line data of Ivarmacitinib tablets in atopic dermatitis indications, the co-primary endpoints of IGA and EASI-75 response rate met expectations, and the efficacy of this product was confirmed. In addition, this product also showed a good safety profile. As investigator, we are very pleased. I would like to express my sincere gratitude to the patients and all the researchers involved in this project. We look forward to the approval of Ivarmacitinib tablets in China as soon as possible for the benefit of atopic dermatitis patients."

"Ivarmacitinib tablets is the first blockbuster product of Reistone since its establishment nearly five years ago. The performance of this phase III clinical studies in atopic dermatitis not only achieved the expected results, but also strictly followed the project schedule. This is also a reflection of our continuous practice of high-quality global clinical trials. We also included some adolescents in this study, and we are pleased that adolescents have also benefited from the treatment,” adds Dr. Min Irwin, CEO and Co-Founder of Reistone, "Based in China and with a global perspective, Reistone is committed to affordable self-developed innovative drugs to patients with autoimmune diseases in China and around the world. The success of the first pivotal Phase III clinical study will strongly promote the company's commercialization!"