What happened?

Shares of Rigel Pharmaceuticals (NASDAQ:RIGL) shot higher on Tuesday after the biotech announced positive topline data from a phase 2 clinical trial for fostamatinib as a treatment for hospitalized COVID-19 patients. The stock closed the trading day up by 16.8%, after having been up by as much as 18.8% late in the session. 

So what

Fostamatinib is already approved in the U.S. and elsewhere as a treatment for adult chronic immune thrombocytopenia. Rigel Pharmaceuticals is currently running a phase 2 study for the medicine in COVID-19 patients in collaboration with the National Institutes of Health (NIH) and Inova Health System, a nonprofit healthcare provider headquartered in Virginia. The trial enrolled 59 hospitalized COVID-19 patients, each of whom received either fostamatinib plus standard of care or a placebo plus standard of care twice a day for 14 days.

Microscopic view of the coronavirus.

Image source: Getty Images.

First, fostamatinib met its primary safety endpoint during the trial. Also, the group of patients who received the medicine had recorded zero deaths at day 29, compared to three deaths in the placebo group.

"Taken altogether, the results of this trial suggest fostamatinib may be a useful addition to improve the outcome of severe and critically ill COVID-19 patients who are at the highest risk of death despite treatment with the best conventional therapies under the current standard of care (including remdesivir and steroids)," said Rigel Pharmaceuticals Chief Medical Officer Wolfgang Dummer.

Now what

With these positive results to show off, Rigel Pharmaceuticals plans on discussing a potential emergency use authorization with the Food and Drug Administration for fostamatinib as a treatment for COVID-19. Although the rollout of vaccines continues, the need for effective treatments for the disease won't dissipate anytime soon. If the healthcare company can earn a conditional green light from regulators for its potential coronavirus medicine, that will likely have a meaningful impact on its financial results. 

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