What happened

Shares of Dova Pharmaceuticals (DOVA) were up 18.5% at 1:33 p.m. EDT today after the biotech, which is focused on thrombocytopenia (low blood-platelet count), announced that the FDA had expanded the approval for Doptelet to include the treatment of that condition in adults with a blood disease called chronic immune thrombocytopenia. This is a second-line approval, meaning patients need to have had an insufficient response to a previous treatment.

So what

Doptelet was already approved in the U.S. to treat thrombocytopenia in patients with chronic liver disease who are scheduled to undergo a procedure. Just two days ago, Dova got the drug approved in Europe for the same liver disease indication.

Dova is getting help from Bausch Health Companies(BHC 1.06%) Salix Pharmaceuticals to sell Doptelet to U.S.-based surgeons looking to use the drug to treat patients with chronic liver disease. That should free up Dova to focus on the launch for immune thrombocytopenia, which is a bigger opportunity, but a disease where Dova will have to go against established drugs, such as Amgen's (AMGN -0.07%) Nplate and GlaxoSmithKline's (GSK 0.19%) Promacta.

Doctor with arm on patient's shoulder

Image source: Getty Images.

Now what

Today's FDA approval is certainly good news, but investors should have patience in their expectations for Doptelet's launch in immune thrombocytopenia. Small biotechs often take awhile to get up to full speed, especially when they have to compete with big pharma.

If the immune thrombocytopenia opportunity doesn't work out as expected, Dova has one more shot to expand sales of Doptelet into chemotherapy-induced thrombocytopenia. Data from a phase 3 study for that version of the disease will be available in first half of 2020.