Talaris Therapeutics' stock falls 21% after reporting patient death in clinical trial

Shares of Talaris Therapeutics Inc. tumbled 21.5% in premarket trading on Thursday after the company reported one of the participants in its Phase 3 study of living donor kidney transplant recipients died. The patient had been diagnosed with a moderate form of acute graft-vs-host disease. The trial's oversight committee has said enrollment and dosing may continue, and it said changes in the study's protocol to mitigate the risk of aGvHD are "sufficient." Talaris shares have declined 84.7% this year, while the broader S&P 500 is down 22.4%.

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