Zai Lab has announced positive results from its Phase III clinical trial of KarXT (xanomeline and trospium chloride) in China for the treatment of schizophrenia. The registrational bridging trial assessed the safety and efficacy of KarXT in 202 acutely psychotic, hospitalized adult patients with schizophrenia.
The Phase III multi-center, randomized, placebo-controlled trial included a five-week double-blind phase, followed by a 12-week open-label extension. The primary endpoint was met, with KarXT demonstrating a significant 9.2-point reduction in the Positive and Negative Syndrome Scale (PANSS) total score compared to placebo at week five.
Clinical Efficacy and Safety
The trial's improvement aligns with previous global studies of KarXT. At week five, the medication led to a 1.9-point reduction in the PANSS positive subscale and a 2.5-point decline in the PANSS negative subscale, compared to placebo. The safety profile of KarXT was consistent with prior trials, with no new or unexpected safety signals reported.
According to Zai Lab's global research and development head and president, Rafael Amado, "The positive findings we observed in this bridging trial will contribute to a large global dataset for KarXT and demonstrate that this novel compound has the potential to be an important new treatment option for adults with schizophrenia in China."
Regulatory Pathway and Market Context
KarXT has been licensed to Zai Lab by Karuna Therapeutics, a company acquired by Bristol Myers Squibb (BMS). The licensing agreement covers development, manufacturing, and commercialization in Greater China, including mainland China, Hong Kong, Macau, and Taiwan.
Zai Lab is preparing to submit a new drug application (NDA) to China’s National Medical Products Administration (NMPA) for the use of KarXT in treating schizophrenia, with a target submission date in early 2025. Schizophrenia affects over eight million individuals in China, highlighting the significant unmet medical need for effective treatments.
Implications for Schizophrenia Treatment
The positive outcomes from this Phase III trial suggest that KarXT could offer a valuable new treatment option for adults with schizophrenia in China. The consistency of these results with previous global studies supports the potential of KarXT to address the symptoms of schizophrenia effectively and safely.
"This clinical trial is an example of Zai Lab’s capabilities as a partner that helps to expand access to innovative treatments in collaboration with our global partners," the company stated.
