Follicular Lymphoma: Idelalisib / CAL 101

Gilead, the company that makes Idelalisib, has submitted an application to the FDA. They seek approval for Idelalisib for use in Indolent Lymphomas (which would include Follicular Lymphoma) in patients that have developed a resistance to Rituxan and alkylating agent chemotherapies (these would include both Cyclophosphamide, the "C" in CHOP and CVP, and Bendamustine). That covers a lot of common treatments. So, basically, if you had chemo and it stopped working, chances are pretty good that you'd be eligible for Idelalisib.

alkylating-agent-containing chemotherapyal

Idelalisib (which has also been called CAL-101 and GS-1101 at various times during its life) is a type of kinase inhibitor that blocks pathways necessary for B cells to survive. The FDA application is based mostly on results from a phase 2 trial that was reported on in June (I wrote about it here). The results were good: 125 patients, Follicular Lymphoma and other indolent lymphomas, with 53.6% achieving an overall response and 89% achieving some measure of lymph node shrinkage.

Curious, though, that they are applying based on phase 2 results; there's no indication from the press release that they are asking for accelerated approved. It's not unheard of to get approval after a phase 2, though phase 3 (which involve a larger base of patients) are more typical. I haven't seen anything on what their strategy is for "going up early," but I'm guessing it's something like "Why not? The worst they can do is say they want to see phase 3 results."

Perhaps, in its favor, is the fact that this will be the first treatment in its class to be approved. There are a whole bunch more behind it in the pipeline that work on a similar mechanism. Collectively, they really change the way we might think about treating Follicular Lymphoma.

I'm certainly hoping for a successful application. Another arrow in the quiver.