What: Juno Therapeutics (JUNO) was up as much as 12% today and ended up 8.6% after an analyst at FBR & Co issued a bullish report.

So what: While it's true that an analyst said nice things about Juno Therapeutics and its shares went up, those two events might not have anything to do with each other. Juno Therapeutics has been on a bit of a tear over the last month, going up for no apparent reason.

JUNO Chart

Even the threat of lower drug prices -- evident on the chart as the dip in the second half of September -- couldn't keep Juno Therapeutics from continuing higher. Every biotech would like to know what Juno has done to catch investors' eyes.

Now what: One possibility is that investors are buying ahead of the American Society of Hematology (ASH) meeting, hoping that good data will be presented. While the meeting doesn't start until December 5, the abstracts for the meeting will be released on November 5 and could have some data on how Juno's clinical trials are progressing.

On the second quarter conference call, CEO Hans Bishop acknowledged that abstracts had been submitted to ASH, but didn't know which might be accepted. While its JCAR015 treatment that targets CD19 is furthest along, we already know that it works fairly well from the early data. Positive data on JCAR018, which targets CD22, might actually be more important because it would show that Juno Therapeutics CAR-T cell technology works with other targets, increasing the potential use of its treatments.