On Thursday, Graphite Bio (GRPH.O) announced the suspension of an early-to-mid-stage trial of its blood disease therapy due to a serious adverse event in the first patient dosed.

The patient required ongoing blood transfusions and experienced sustained low blood cell counts after receiving Graphite′s nula-cel therapy, which the firm says is probably connected to its medication. According to Graphite, patients have shown no signs of blood cancer, which they have reported to the U.S. Food and Drug Administration (FDA).

The FDA-designated "fast track" drug Nula-cel was being investigated as a potential therapy for sickle cell disease, which causes an inadequate supply of healthy blood cells because sickle-shaped red blood cells are produced instead of round ones. 

(Source: https://www.reuters.com/business/healthcare-pharmaceuticals/graphite-bio-pauses-early-stage-blood-disease-therapy-trial-2023-01-05/ )