What happened

Shares of ImmunoGen (NASDAQ:IMGN) are up 11.6% at 3:33 p.m. EDT on no apparent news.

So what

Beyond the distinct possibility that the move is just day traders having a field day -- it was up as much as 21.7% at one point today -- it's also possible that investors are buying ahead of the release of abstracts for the American Society of Clinical Oncology (ASCO) meeting on Wednesday evening.

Cancer patient holding hands with a friend

Image source: Getty Images.

ImmunoGen is expecting to release two sets of data that could give investors confidence in its lead drug, mirvetuximab soravtansine. Positive data from pooled phase 1 trials testing the drug as a monotherapy would make it more likely that ImmunoGen's ongoing FORWARD I trial testing mirvetuximab soravtansine as a monotherapy in patients with platinum-resistant epithelial ovarian cancer will be successful.

There will also be an ASCO presentation from the FORWARD II trial that's testing mirvetuximab soravtansine combined individually with other cancer treatments. Activity beyond what would be expected for the other cancer treatments alone would be a good sign that mirvetuximab soravtansine is an active drug and would give ImmunoGen a backup plan if the monotherapy doesn't work.

Now what

While investors will get a peek at the two sets of data when the abstracts are released at 5:00 p.m. EDT on Wednesday, it won't be the most up-to-date data since researchers had to submit the abstract in either February or March depending on whether it's a normal or late-breaking data submission, respectively. It appears ImmunoGen's are of the normal variety.

Investors will have to wait until the actual meeting on June 3 to see the most recent data, which will be especially important for the FORWARD II trial, where the company has only recently completed dosing for some of the combinations.

Brian Orelli has no position in any stocks mentioned. The Motley Fool recommends ImmunoGen. The Motley Fool has a disclosure policy.