What happened
Vertex Pharmaceuticals (VRTX -0.76%), a commercial-stage biotech specializing in treatments for cystic fibrosis, saw its share price rise on Tuesday thanks to news about one of its pipeline programs. As a result, its stock climbed by nearly 3% on the day, in contrast to the S&P 500 Index's 0.2% slump.
So what
That morning, Vertex and partner CRISPR Therapeutics (CRSP -3.45%) announced that the former company has secured a rolling review from the U.S. Food and Drug Administration (FDA) for exagamglogene autotemcel (exa-cel) to treat a pair of maladies: Sickle cell disease (SCD) and transfusion-dependent beta thalassemia (TDT).
Exa-cel is described by Vertex as "an investigational, autologous, ex vivo CRISPR/Cas9 gene-edited therapy... in which a patient's own hematopoietic stem cells are edited to produce high levels of fetal hemoglobin" or HbF. HbF is the type of oxygen-carrying hemoglobin present during the development of the fetus. It changes to "adult" hemoglobin following birth.
Vertex added that increasing HbF could potentially alleviate the transfusion requirements of those with TDT. It can also reduce sickle crises for SCD patients.
Now what
The FDA's acceptance of exa-cel for a rolling review certainly moves the regulatory process along. Yet investors were understandably cautious -- the treatment is still being put through its paces in clinical trials, so as ever in the biotech world, success is not assured.
At the moment, exa-cel is in phase 1, 2, and 3 open-label trials in patients aged 12 to 35 years with one of the two afflictions. Enrollment has been closed, and the participants will be monitored for roughly two years after being administered the treatment. The company also plans to enroll some of the participants in a long-term study of up to 15 years in duration.
