What happened

Shares of Blueprint Medicines (NASDAQ:BPMC), a clinical-stage biotechnology company developing targeted cancer therapies, gained 75% in the first half of 2019, according to data from S&P Global Market Intelligence. By filing a new-drug application following clinical-trial success, the company gave investors reasons to cheer.

So what 

Blueprint Medicine's lead candidate avapritinib is a small-molecule drug that's designed to freeze mutant kinases into an inactive state so they stop promoting tumor growth. Acquisitions of Loxo Oncology and, more recently, Array BioPharma (NASDAQ:ARRY) suggest Blueprint has what deep-pocketed pharmaceutical companies are eager to buy: An ability to develop drugs that hit hard to reach targets previously considered "undruggable."

Man on a roof with a rocket strapped to his back, ready for take-off.

Image source: Getty Images.

Blueprint Medicine's stock made its biggest leap of the year thanks to data from the Navigator trial in patients with genetically defined tumors of the stomach and small intestine. Avapritinib shrank tumors for 86% of patients with PDGFRA exon 18 mutant gastrointestinal stromal tumors (GIST) when given to a group that was newly diagnosed or had already relapsed once or twice following standard care.

Blueprint's kinase inhibitor also shrank tumors for 22% of GIST patients who had already relapsed at least three times. Gleevec and other oral treatments that inhibit a wide range of kinases are already used to treat GIST, but none appear as easy to tolerate as avapritinib. That's probably because they're far less specific and shut down kinases that healthy cells need to function.

Now what

Last month, Blueprint Medicines submitted avapritinib's application to the Food and Drug Administration (FDA), and the agency has 60 days to peruse it before committing to an official review. There's a heap of information in a new-drug application, so we probably won't hear from the regulator until the second week of August.

Blueprint isn't going to lie around waiting for the FDA to call. In the first quarter of 2020, the company plans to submit its second new-drug application. The company's RET inhibitor BLU-667 shrank tumors for 60% of lung cancer patients with RET-fusion mutations. 

Blueprint's market cap has risen to $4.7 billion, which is a lot for a company without anything to sell but low enough to make sense if its targeted cancer therapies continue to impress. Don't be surprised if this is one of the next biotechs to receive a juicy buyout offer.

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