(Reuters) - Gene therapy firm Graphite Bio said on Thursday it was pausing an early-to-mid-stage trial of its blood disease therapy due to a serious adverse event in the first patient dosed, sending its shares down nearly 48% in after hours trading.
After being given Graphite's therapy, nula-cel, the patient showed prolonged low blood cell counts and required continued transfusion of blood, which the company believes is likely related to its treatment.
Graphite said it has reported the incident to the U.S. Food and Drug Administration (FDA), and the patient has shown no evidence of blood cancer. The company is continuing a detailed assessment of the incident and also considering changes to the manufacturing process of its therapy.
In light of the pause, Graphite said it no longer plans to seek the U.S. health regulator's permission to test its other experimental therapy, GPH102, in humans by mid-2024. The gene therapy firm said it was also looking to identify ways to extend its cash position to at least 2026, from previously reported cash runway of fourth quarter 2024.
Nula-cel, which holds FDA's 'fast track' tag, was being studied as a potential treatment for sickle cell disease, which leads to a shortage of healthy blood cells due to the sickle-shape instead of the round shape of red blood cells.
The condition impacts about 100,000 people in the United States and can cause complications such as infection, acute chest syndrome and stroke.
(Reporting by Bhanvi Satija in Bengaluru; Editing by Shailesh Kuber)