What happened

After disclosing that the Food and Drug Administration has accepted the company's application to review its lead product candidate for approval, shares of Global Blood Therapeutics (NASDAQ:GBT) rallied 10.9% on Thursday.

So what

The company is developing voxelotor, a once-daily oral treatment for sickle cell disease (SCD) that may prevent red blood cells from becoming misshapen. 

Gold and silver pills on top of a pile of $50 and $20 bills.

Image source: Getty Images.

Positive clinical trial results for the drug, which boosts the amount of oxygen in hemoglobin, were reported in December. At the 12-week mark, a 1,500 mg daily dose of voxelotor increased hemoglobin by at least 1 gram per deciliter in 65% of patients. Only 10% of patients receiving a placebo saw that level of improvement. 

The company followed up that data with additional insight in June. At the 24-week mark, 59.5% of patients saw a 1-gram-per-deciliter improvement in hemoglobin, including 51.1% in its intent-to-treat (ITT) group. Only 6.5% of the ITT group receiving placebo had a similar improvement. 

The drug's potential to significantly improve SCD treatment by reducing the risk of life-threatening anemia prompted the FDA to approve a pathway to accelerated approval, leading to management submitting an application for approval that was accepted by the regulator this week. The acceptance of its application starts a clock for review that should result in a go/no-go decision on the drug in early 2020. 

Now what

The average life span of a sickle cell patient is 20 to 30 years shorter than a healthy person's, and costs associated with care can run into six figures annually. New treatment options, such as voxelotor, are needed.

There's no guarantee Global Blood Therapeutics' application will win a green light, but it chances are strengthened by word that the FDA doesn't currently plan an advisory committee review of the drug before making its decision. Gene therapies in development could make this an increasingly competitive marketplace someday, but a six-month priority review by the FDA suggests voxelotor could become available as soon as Feb. 26, 2020, giving it an important head start in this blockbuster indication.