Graphite breaks apart, with founder inking deal for abandoned sickle cell prospect, gene-editing tech
Matthew Porteus, M.D., Ph.D., is trying to write another chapter for his sickle cell disease project. Three years after Graphite Bio launched to build on his work, Porteus has struck a deal to save the floundering project and advance deeper into the clinic under a new biotech.
Porteus studied the use of CRISPR to correct the mutation that drives sickle cell at his Stanford University lab. The studies led to Graphite, which listed Porteus as a scientific founder when it emerged with a $45 million series A round in 2020. Graphite’s story quickly took a dark turn, with the biotech seeing a serious adverse event in the first patient it dosed and halting development of the candidate weeks later.
Those events marked the beginning of the end for Graphite, which went from raising a $238 million IPO to entering into a reverse merger in less than 30 months. But Porteus has given the sickle cell program a chance of outliving the biotech that first tried to bring it to market.
The Stanford professor has co-founded a new biotech, Kamau Therapeutics, to emerge from the ashes of Graphite. Kamau “received an option to acquire all genome editing assets” through a “strategic transaction with Graphite.” The newly minted biotech plans to study the sickle cell asset, nulabeglogene autogedtemcel (nula-cel), that Graphite walked away from in the wake of the adverse event.
Investigators have now tracked the patient who received nula-cel for one year. Ahead of the release of the one-year data Monday, Kamau shared a look at six-month results, identifying “lower-than-expected cell survival rate, necessitating platelet and red blood cell transfusions due to low platelet counts” as a problem and fingering eltrombopag as the cause of the adverse event. Eltrombopag is used to treat low platelets in the blood and was not initially part of the trial protocol.
The findings have informed a focus on manufacturing. Kamau is working with an outsourcing partner to increase cell yield and improve overall cell health. The goal is to establish a more robust manufacturing framework.
Graphite entered into a license and option agreement with an undisclosed third party in August. Under the terms of the deal, the third party secured an option on nula-cel and related assets and gave Graphite a 20% stake in its business. The option was contingent on the timely achievement of “a financing milestone” by the third party. Graphite’s last update described a tweak it made to the agreement in September.
Meanwhile, what’s left of Graphite folded into vision-loss biotech LENZ Therapeutics in November.