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What happened

After reporting that it placed a key trial on voluntarily hold, shares in Juno Therapeutics (NASDAQ:JUNO) lost 19.3% of their value in November, according to S&P Global Market Intelligence.

So what

Juno Therapeutics is in a foot-race to develop chimeric antigen receptor T-cell (CAR-T) therapies for use in treating tough-to-treat cancer patients. The company's lead product candidate, JCAR015, has been under development for use in patients with relapsed/refractory B cell acute lymphoblastic leukemia.

JCAR015's ALL trial was halted this past summer following two deaths caused by brain swelling, however, the trial was quickly restarted after changes were made to the chemotherapy preconditioning regimen used prior to the administration of JCAR015. Unfortunately, two more patients have passed away in the trial because of brain swelling, casting significant doubt on the program's safety and ability to proceed.

Absent discovering that these cases of brain swelling were caused by something other than JCAR015, management has left the door open for shutting down this trial to focus on its other ongoing studies. 

Now what

Juno Therapeutics entered this year hoping to advance JCAR015 for ALL to the FDA for approval in 2017. That timeline was pushed back to 2018 when the JCAR015's trial was halted in July, and now that the program has been halted again, it's unclear when, or if, this drug will make its way to regulators.

Regardless, it appears Juno Therapeutics has lost the chance to be the first-to-market with a CAR-T therapy. Kite Pharma and Novartis are advancing their own programs in other cancer indications, and they're still on pace to discuss their respective therapies with regulators next year. For instance, Kite Pharma announced earlier this week that it has begun a rolling application for approval of KTE-C19 for B-cell cancer. 

The shuttering of this JCAR015 trial, however, doesn't mean that Juno Therapeutics is out of options. The company's got a number of intriguing next-generation CAR-T's in development that will read out data over the next couple years.

Assuming Juno Therapeutics' other therapies don't fall victim to the same safety stumbles as JCAR015, the company still has a shot at carving out market share in what's likely to be a billion dollar market for CAR-T therapy.

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