Kezar Life Sciences’ autoimmune drug candidate has been put on hold by the FDA after the company said last week that four patients died in a Phase 2b lupus nephritis trial.
The patients were in the Philippines and Argentina, and died after treatment with the company’s drug zetomipzomib. Three of the people shared “a common pattern of symptoms and proximity to dosing,” according to Kezar. Other patients with a “similar proximity to dosing” had serious but non-fatal side effects.
Kezar said it expected an update from the FDA within 30 days.
Chris Kirk“We are steadfastly committed to patient safety and have directed our efforts to investigate these cases as we look to continue the zetomipzomib development program,” Kezar CEO Chris Kirk said in a press statement announcing the hold.
A separate Phase 2a test of zetomipzomib in autoimmune hepatitis is going ahead as normal, with no grade 4 or 5 events reported, according to the company. The selective immunoproteasome inhibitor has been described by Kezar as a potential pipeline-in-a-pill for autoimmune conditions.
The drug is one of just two in the biotech’s pipeline alongside a Phase 1 advanced solid tumor asset called KZR-261. In August, the company stopped enrollment in the KZR-261 study after researchers saw no objective responses, with Kezar shifting its resources towards zetomipzomib development instead.
In October, the drugmaker axed 41% of its staffers and stopped all preclinical R&D in a bid to cut costs and better fund its clinical-stage work. Kezar had $164 million in cash, equivalents and marketable securities as of the end of June.