Kezar Life Sciences' Strategic Shift
Kezar Life Sciences has decided to halt the development of its phase 1 solid tumor drug known as KZR-261. This decision comes as the company chooses to focus its resources on its promising treatment for autoimmune hepatitis.
Status of KZR-261
The phase 1 trial for KZR-261 involved 61 patients, but unfortunately, it did not yield the desired results. There were no objective responses reported, meaning the drug did not produce measurable improvements in tumor size or patient health. Although some patients experienced stable disease—a condition where the disease does not progress—for four months or longer, this was insufficient to justify continuing the trial.
Zetomipzomib Takes the Lead
In contrast, Kezar has shown confidence in its lead candidate, zetomipzomib, a selective immunoproteasome inhibitor. This drug is currently being tested in a phase 2 trial for patients with autoimmune hepatitis, known as the PORTOLA trial, which has successfully completed enrollment with 24 patients. The company expects to announce initial results in the first half of 2025.
Future Prospects and Trials
Kezar is also conducting a global trial called PALIZADE to test zetomipzomib in treating lupus nephritis, with results anticipated in 2026. Additionally, the rights to develop zetomipzomib in China, South Korea, and Southeast Asia have been acquired by Everest Medicines, who have already started patient dosing in China.
Company Restructuring
KZR-261 was originally the first drug to emerge from Kezar's innovative protein secretion platform. However, after a significant restructuring in 2023, which included a 41% reduction in staff, the company decided to concentrate its efforts on drugs with the most potential impact. This restructuring also saw the departure of key personnel, including former Chief Medical Officer Noreen Henig, M.D.
Conclusion
As Kezar pivots its focus, it underscores the strategic decisions companies must make in drug development and resource allocation. The successful development of zetomipzomib could offer a much-needed treatment for autoimmune conditions, providing hope for patients with limited options.
