At the American Society of Clinical Oncology (ASCO) annual meeting in Chicago, Illinois, Tycel Jovelle Phillips, MD, City of Hope National Medical Center, Duarte, California, outlined updated data from a phase 1b study regarding the safety and efficacy of BTK inhibitor acalabrutinib in combination with bendamustine and rituximab among patients with treatment-naive or relapsed/refractory mantle cell lymphoma (MCL).

Transcript:

Hi, I'm Dr. Tycel Phillips, an associate professor at the City of Hope National Medical Center. We'll just briefly discuss our abstract, looking at acalabrutinib in combination with bendamustine and rituximab in patients with treatment-naive or relapsed/refractory mantle cell lymphoma.

So overall, with mantle cell lymphoma in the frontline setting—because there isn't truly a standard of care—but for the most part for certain patient populations, especially those who are not eligible for target stem cell transplantation, bendamustine and rituximab has been a mainstay of treatment.

Trying to find ways to improve upon that has been an important research goal for a lot of practitioners. And even in the relapsed/refractory setting, while we know that BTK inhibitors are well-established in the second line and beyond, again, we do know that about a third of patients will have some primary refractory disease to BTK inhibitors. So again, ways to try to improve upon this are things that we would all looking for.

[In] this study, the main goal was to evaluate the safety of this and the efficacy of the combination, with the hopes of moving this into a frontline setting. Then so, ideally, the main focus of the study was really the treatment of [any] patient population, but again, because of the novelty of it, it was explored in the relapsed/refractory setting as well. And so, what we saw from this study was that we did not notice any new adverse events with the combination, whether in treatment-naive or in the relapsed/refractory setting.

We did see very impressive overall response rates and the duration of response, which was better in the treatment-naive patients than in the relapse/refractory setting, which is understandable given the selection of more resistant patients in a relapse refractory setting. 

I think the key point of this is that this study led to the incorporation of acalabrutinib, and bendamustine and rituximab in the ECHO trial, which was a randomized study that evaluated the combination of bendamustine and rituximab and acalabrutinib, versus bendamustine and rituximab in patients with newly diagnosed mantle cell lymphoma who are not eligible for stem cell transplantation. So this sort of led the groundwork for that trial, which is ongoing, and we hope to have some results from the ECHO trial soon. 

But I think as we'll present in our abstract and show was, again, impressive overall response rate, complete response rate, especially in treatment-naive patients, without any new safety signals, suggesting that the combination would be safe, which is an important thing to consider, given some of the recent data with some of these combinations with bendamustine.

Source:

Phillips TJ, Wang M, Robak T, et al. Safety and efficacy of ABR in pts with TN or R/R MCL: Ph Ib trial. Presented at ASCO Annual Meeting; June 2-6, 2023; Chicago, IL. Abstract 7546.