Sunday, February 28, 2016

New Treatent Approved for Follicular Lymphoma

The FDA announced on Friday that it has approved Obinutuzumab (also known as Gazyva) as a treatment for Follicular Lymphoma. This is good news.

Obinutuzumab is a humanized monoclonal antibody that targets CD20. So it's a lot like Rituxan, which also targets CD20. The big difference is that Obinutuzumab is humanized -- made from human cells, not mouse cells, like Rituxan. There is some feeling that this will make it safer than Rituxan and will cause fewer allergic reactions.

The specific treatment that was approved involves Obinutuzumab + Bendamustine, followed by Obinutuzumab on its own. It is meant for patients who took Rituxan + chemotherapy, but who have had the disease return within 6 months.

The approval was based on the GADOLIN study, which involved 321 FL patients (along woth some other NHLs), which compared the Obinutuzumab + Bendamustine + Obinutuzumab, to Bendamustine on its own. Patients who were given only Bendamustine had a median Progression Free Survival (the time it took for the FL to come back) of 13.8 months. The Obinutuzumab patients had a median PFS of 29.2 months -- more than a year, and more than double the Bendamustine results.

Those are good results.

It will be interesting to see if Obinutuzumab gets a lot of off-label use as a single-agent treatment, given that it is similar to Rituxan. But it's more likely that it will be used in combination treatments, the way Rituxan is used so often. there are already a bunch of trials for Obinutuzumab combinations.

So we have another arrow in the quiver. Cause for celebration.


Anonymous said...

Great news. Any information on well it works compared to Rituxian?

Love your stuff!

Lymphomaniac said...

Thanks for reading.
The Journal of Clinical Oncology published an article last August that compared single-agent Obinutuzumab and Rituxan in indolent NHL (including a bunch of Follicular Lymphoma patients). They found that Obinutuzumab had a higher Overall Response than Rituxan (44.6% to 33.3%), but there was no difference in Progression-Free Survival. This was in a phase II trial, and they call for a larger phase III trial to get more information. To me, that confirms a couple of things: 1) it's still really hard to improve on Rituxan, and 2) my guess is that Obinutuzumab's future is in combinations with other agents. (If you want to read the full JOC article, it's here:

Mike said...

Bob, what do you think may be the practicality of Obin replacing Rituxan if and when the patients develop resistance, aka refractory?

Another interesting development is the conjugated -mab, for example the 2 ongoing Seattle Genetics clinical trials.


Lymphomaniac said...

In my completely non-expert opinion, I don't think Obinutuzumab will replace Rituxan for refractory patients. I don't think it has much future as a single agent; too many other things to try of a MAB fails on the first try. Nothing seems to be able to beat Rituxan. Some come close, but nothing seems to be a measurable improvement. Something about MABs, I guess -- there's just a natural threshold for effectiveness, for whatever reason. (Again, that's a non-expert opinion.)
The Seattle genetics MAB (Brentuximab Vedotin) looks interesting. Already a trial for combining it with Bendamustine. We'll see what happens -- if my MAB threshold theory holds true.