Interim analysis of the phase 2 cohort of ZX-7101A phase 2/3 adaptive design pivotal study (registration number: CTR20221729), a multicenter, randomized, double-blind, placebo-controlled study, aims to evaluate the safety and efficacy of ZX-7101A tablets versus placebo. The seamless adaptive design consists of two relative independent cohorts: phase 2 dose exploration and subsequently phase 3 efficacy confirmation. The study has been conducted in more than 60 centers across China and led by Professor Wenhong Zhang, Director of the National Center for Infectious Diseases (Shanghai) and Professor Jing Zhang at Huashan Hospital affiliated to Fudan University.

Phase 2 cohort enrolled 177 subjects with acute influenza infection in total, randomized into ZX-7101A treatment groups (40 mg, 80 mg) and placebo group. Statistical significance was reached in the primary end point of time to alleviation of all influenza symptoms between both ZX-7101A treated groups relative to the placebo group (p-value: 0.008 for the 40 mg group and 0.022 for the 80 mg group respectively). In particular, the median time to alleviation of all influenza symptoms in the ZX-7101A 40 mg group was shortened by 44.1% in comparison to the placebo group. Secondary efficacy endpoints including time to cessation of viral shedding determined by virus RNA, time to alleviation of the four systemic symptoms (muscle or joint pain, fatigue, headache, feverishness or chills), and time to alleviation of the three respiratory symptoms (nasal congestion, sore throat, cough) also showed significant benefits in both ZX-7101A treatment groups compared to the placebo group. In both 40 mg and 80 mg groups, ZX-7101A was well tolerated without evident safety findings.

"We are pleased to see favorable safety and efficacy of ZX-7101A in the phase 2 clinical study." said by Professor Wenhong Zhang, "The outbreaks of flu around the globe earlier this year have posed a threat to the public health and an urgent need for effective influenza treatment. The pivotal phase 2/3 study of ZX-7101A was completed in a very short period of time through the joint efforts of Zenshine Pharmaceuticals and the investigators. I have to say it's a miracle and can be considered as a new milestone of the speed of clinical development in China. In response to future pandemics, clinical development of innovative treatment can be accelerated benchmarking against ZX-7101A development model."

Dr. Jinfu Yang, the chairman of Zenshine Pharmaceuticals said, "We are encouraged by the exciting interim safety and efficacy data of ZX-7101A in adults. ZX-7101A could be the best-in-class CEN inhibitor in comparison to all the reported phase II results. Subject enrollment of phase 3 cohort has been completed by March 2023 and the full analysis will be done by mid-2023. We expect ZX-7101A to be launched in the near future to help the infected individuals recover fast and to prevent and battle the flu outbreak, which has always been a major threat to public health."