Shares of Crispr Therapeutics dipped Friday after the Food and Drug Administration indicated it could approve the company's gene-edited sickle cell treatment as early as December. CRSP stock had been up more than 7% in premarket action before falling.
Crispr's drug is called exa-cel. It works by increasing hemoglobin levels in patients with sickle cell disease and beta thalassemia. Late Thursday, the FDA said it would make an approval decision on exa-cell in the former disease by Dec. 8, and in the latter disease by March 30.
Vertex Pharmaceuticals partnered with Crispr to develop exa-cel. Vertex Chief Executive Reshma Kewalramani noted the companies also are working to file for approval in Europe and the U.K.
"Exa-cel holds the promise to be the first CRISPR gene-editing therapy to be approved, and we continue to work with urgency to bring this treatment with transformative potential to patients who are waiting," Kewalramani said in a written statement.
On today's stock market, CRSP stock went from gains to drops and closed down 2.2% at 61.24. Vertex shares edged rose a fraction to 334.11.
CRSP Stock: Promising New Data
Crispr and Vertex also unveiled the data backing their requests for approval.
The companies tested exa-cel in 48 patients with beta thalassemia who need regular blood transfusions and 35 patients with sickle cell disease. They were able to evaluate 27 and 17 patients, respectively, from each group.
Of the 27 beta thalassemia patients, 24 didn't need any blood transfusions for a year following treatment. One of the remaining three has since stopped transfusions and hasn't needed any for 2.9 months. The others have had 80% and 96% reductions in the volume of their transfusions.
Bullishly for CRSP stock, patients were free of transfusions for a median of 20.5 months. One patient didn't need transfusions for 40.7 months.
In the sickle cell group, 16 out 17 patients — 94.1% — didn't experience any painful episodes called vaso-occlusive crises for a year following treatment. The patient who didn't hit this mark had a complex set of health conditions, including chronic pain. Another patient had a vaso-occlusive crisis at 22.8 months while sick with parvovirus.
Patients were free of vaso-occlusive crises for a median of 18.7 months. One patient was free of episodes for 36.5 months.
Beta Thalassemia Decision Trails
RBC Capital Markets analyst Brian Abrahams says any news is a net positive for Crispr and Vertex's drug. If approved, exa-cel would be the first drug using CRISPR-based gene editing to hit the market.
In this case, the drug itself is gene-edited — a process known as ex vivo editing — before it is infused into the patient. Other drugs in testing would perform the genetic edits inside the body — or in vivo editing.
Abrahams noted it's "a bit surprising" that the FDA granted exa-cel a speedier review in sickle cell disease than beta thalassemia. But a delay in beta thalassemia likely won't have a material impact on sales nor CRSP stock.
"Nonetheless, the priority review designation is far more important for sickle cell disease, which comprises the majority of our U.S. revenue estimates," he said in a note to clients.
Abrahams has a sector perform rating on Vertex shares, and didn't list a rating for CRSP stock.
Follow Allison Gatlin on Twitter at @IBD_AGatlin.
