Mengyang Di, MD, PhD, Cancer Outcomes, Public Policy, and Effectiveness Research Center, Yale University School of Medicine, New Haven, CT, discussed a population-based analysis on real-world practice patterns and outcomes following Bruton Tyrosine Kinase inhibitors (BTKi) in older patients with mantle cell lymphoma at the 64th ASH Annual Meeting.

Transcript

Hello everyone. My name is Mengyang Di. I'm a third-year hematology/oncology fellow at Yale University. Today, I'm going to present to you our poster, a population-based analysis on the real-world practice patterns and outcomes following the BTK inhibitors in older patients with mantle cell lymphoma. So, the management in mantle cell lymphoma has changed dramatically over the past several years. This includes the approval of three BTK inhibitors over the past several years. Our previous population-based analysis also showed the significant overall survival in mantle cell lymphoma since the approval of the first BTK inhibitor in 2013. So, BTK inhibitor is a continuous therapy, which means that in the majority of the patients, they have to continue to take the medication on a daily basis in order to derive clinical benefit from it. And early discontinuation of the BTK inhibitor in the real-world practice can be a major issue due to the early disease progression or intolerance.

This can be a more important issue in the older population because of the relatively more limited treatment options following the discontinuation of the BTK inhibitors. So, early discontinuation has been described in a couple of real-world analyses so far. One was from a single center analysis in the US. The other one was from a multicenter analysis based on the European population. And both studies actually suggested early discontinuation can be a very important issue in treating patients with mantle cell lymphoma in the relapse/refractory setting, especially. So far we still don't have any data, any population-based data or large-scale data on early discontinuation of using BTK inhibitors in older patients with mantle cell lymphoma in the US. So this prompted our current analysis. Our study used the population-based the SEER-Medicare database to identify older patients with mantle cell lymphoma who received BTK inhibitors in the relapse/refractory setting.

And we looked at the duration of continuing BTK inhibitors, the survival outcomes following the initiation of the BTK inhibitors, as well as the practice patterns and survival outcomes upon discontinuation of the BTK inhibitors. So our study included 332 patients and the majority of our study population received their BTK inhibitor in the second-line setting. And we used the Kaplan-Meier methods to estimate the duration of continuing BTK inhibitors in our analysis. We followed patients since the initiation of their BTK inhibitor to the discontinuation, death, or the end of follow-up. And we consider patients who died while they were still on BTK inhibitors and patients who were still on the BTK inhibitor at the end of our follow-up as being censored. And based on our analysis, the medium duration of being continued BTK inhibitor was 7.7 months. And we also estimated the percentage of patients remained on BTK inhibitor by 12 months after the initiation.

A little bit less than 50% of patients were still on the treatment and this number dropped to 20% to 30% by 24 months after the patients were started on the BTK inhibitor. And the medium overall survival was close to 20 months since the initiation of the BTK inhibitors. And then the management of following the discontinuation of the BTK inhibitors are quite heterogeneous, actually. And this includes chemo, immunotherapy, and novel agents such as venetoclax-based regimen or lenalidomide-based regimen. And regardless of the treatment regimens used in patients following the discontinuation of the BTK inhibitors, the survival outcomes were dismal in general. And the medium overall survival following the discontinuation of the BTK inhibitor in our study population was 7.7 months.

So, I think, our study really showed that in the real-world practice, the early discontinuation of BTK inhibitors can be an issue. And the practice following the discontinuation is variable or heterogeneous. And the survival outcomes following the discontinuation are also poor. And, I think, moving forward, we really need some more studies to look into what are the specific reasons patients with mantle cell lymphoma, especially the older population coming off BTK inhibitors and in patients who discontinue the BTK inhibitors because of intolerance. We really have to come up with some quality improvement measures to try to keep them on the BTK inhibitors so that they can continue to derive clinical benefit for as long as possible.