The journal HemaSphere published new research last week on another Epcoritamab combo. It's an early trial, but it could be an effective treatment for some patients.
Epcoritamab has been getting a lot of attention lately. If you've been a regular reader, you know I've been saying for a few years that that the treatments that seem to get oncologists most excited these days are CAR-T and Bispecifics. And he bispecific that gets them most excited is Epcoritamab.
A quick reminder: a bispecific works by targeting two different proteins. One of them is on the surface of the cancer cell. So it works a lot like Rituximab, which also targets a protein on the cancer cell. But a bispecific also targets a different protein on a different cell -- a T cell, which is an immune cell. So bringing a cancer cell close to an immune cell, the bispecific helps the immune system work against the cancer.
Epcoritamab works by targeting the CD20 protein on the cancer cell (just like Rituxan does) but also the CD3 protein on the T cell. It works very well, and there are more and more reports of it being used successfully in various combinations (like the recent presentation on Epcoritamab + R-Squared).
In this research, the combination is Epcoritamab + Bendamustine + Rituxan. As many of you now, Bendamustine is a traditional chemotherapy. The article from HemaSphere is called "First-line treatment with epcoritamab in combination with bendamustine plus rituximab induces sustained remissions beyond 3 years in patients with follicular lymphoma."
It's a pretty straightforward title. The article describes a phase 1b/2 clinical trial (meaning it looks at safety, like a phase 1 trial, but also effectiveness, like a phase 2 trial). The study involves 25 patients from the trial who have been diagnosed with Follicular Lymphoma but had not yet received any treatment. The patients received Epcoritamab + BR and thenwere given additional Epcoritamab for up to 2 years.
At a median follow-up of 41.3 months, the Overall Response Rate and the Complete Response Rate were both 96%. In other words, 24 of 25 patients had a Complete Response. That's very high, and I can't remember any trial where the OR was the same as the CR. And at a median of 36 months, 87% of patients had kept that Complete Response. The 3 year Progression Free Survival was 83%, and the 3 year Overall Survival was 96%.
As for safety, the combination did not produce any new side effects, just the ones that were expected with either Epcoritamab or BR. However, those expected side effects were not minor. There was no high-grade Cytokine Release Syndrome (CRS) or ICANS (Immune Effector Cell Neurotoxicity Syndrome), which are perhaps the most serious possible side effects, though lower-grade CRS occurred in 68%. But there were other side effects. 92% of participants reported infections (a sign of a weakened immune system), with COVID-19 being the most common (patients were enrolled in 2021). Injection site reactions in 56%. Fatigue in 52%. The most common grade 3side (more serious) side effects were infection (44%), and low white blood cell counts. In all, 72% of patients experienced a grade 3 or higher side effect of some kind.
The researchers point to the high CR rates and long duration as very positive things. But they also point out that a combination like this can potentially bring about serious side effects, and caution doctors to think very carefully about which patients would benefit from it instead of a different treatment with less serious side effects.
It's a small study, very early in the process, but probably justifies moving on to a larger study. It will be very interesting to see if the side effects become an issue. Epcoritamab is part of our future, no question. But how it ends up in our future -- as a single agent or in some combination -- will be worked out over the next few years.