SHANGHAI, Nov. 15, 2022 /PRNewswire/ -- Reistone Biopharma (Reistone), a leading biotech company focused on development of innovative medicines for immune and inflammation diseases, today announced positive results from a Phase III study – QUARTZ3 (NCT04875169) evaluating 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 the first National Class A new drug for atopic dermatitis designed and developed in China. In January 2021, based on its excellent 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.

Atopic dermatitis is one of the most common skin conditions affecting up to 10% of the adults and 20% of children.  This chronic, relapsing inflammatory disease is associated with intense itchiness and chronic scratching leading to scaly and oozing skin, these symptoms can severely affect individuals' quality of life. The results of this Phase 3 clinical study have revealed the best potential of Ivarmacitinib tablets in their class in improving skin inflammation and itchiness. 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.

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. The average course of disease was more than 10 years, and about 40 percent of the participants had previously received systemic therapy. The study also included a proportion of adolescent patients aged 12 years and older, and the results showed that the optimal efficacy trend of Ivarmacitinib 8mg or 4mg in adolescent patients was consistent with the general population. 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", said Professor Zhang Jianzhong, Principal Investigators of this study, Director of Dermatology, Peking University People's Hospital, "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", said 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!"

About Ivarmacitinib tablet

Ivarmacitinib tablet is a potent and 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.

About Atopic Dermatitis (AD)

Atopic Dermatitis (AD) is a chronic inflammatory skin disease that poses a significant burden on not only patients' quality of life but also the health care system. It is a complex disease with a wide spectrum of clinical presentations and combinations of symptoms, including patches of skin that are red or brownish, dry, cracked, or skin that is scaly and itchy, especially at night. AD affects up to 20% of children and up to 3% of adult; recent data has shown that the prevalence in both children and adults is increasing, especially in low-income countries. While biologics are an important addition to the treatment landscape, there remains a great need for innovative, easily manageable, and affordable therapies for AD patients.

About Reistone Biopharma

Reistone Biopharma Co. Ltd. is a leading biopharmaceutical company focused on developing novel medicines aimed at treating autoimmune and inflammatory diseases that have high unmet needs. The company was founded in January 2018 and is headquartered in Shanghai, China with additional operations in 10 more cities, and Chicago and Boston in United States. The company gathers the world's top clinical and drug discovery talents, and prides itself on industry-leading clinical trial efficiency. The company's drugs under development are all national Class A new drugs, and more than ten clinical trials are currently in progress; Several self-developed molecules have entered the preclinical research stage. Further information about the company and its drug development programs and capabilities may be found online at http://www.reistonebio.com.

Contact Information
Aik Han Goh
Chief Medical Officer
Aik.goh@reistonebio.com

SOURCE Reistone Biopharma