Rituximab Maintenance Following First-line BR/R-CHOP Offers Significant Real-World Benefits in MCL

Mantle Cell Lymphoma

Maintenance treatment with rituximab (Rituxan) following first-line treatment with rituximab plus bendamustine (Bendeka; BR) or rituximab plus cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP) produced an overall survival (OS) benefit in older patients with mantle cell lymphoma (MCL), according to findings from a real-world analysis.

Data presented at the 2022 ASCO Annual Meeting showed that patients who received rituximab maintenance following first-line BR or R-CHOP had a 49% reduced risk of death vs patients who did not receive rituximab maintenance (HR, 0.51; 95% CI, 0.34-0.76).

Rituximab maintenance has shown to improve OS in older patients with MCL following frontline treatment with R-CHOP. However, BR has become a more prevalent first-line treatment option for patients with MCL.

Investigators in the real-world study aimed to evaluate the first-line treatment pattens for patients with MCL and examine the effectiveness of rituximab maintenance following standard frontline chemoimmunotherapy.

The real-world study identified patients the SEER-Medicare 2020 database who were at least 66 years old and diagnosed with MCL from 2007 to 2017. Patients were required to have continuous Medicare A/B/D coverage and have received MCL therapy. Patients who met those criteria also needed to have received BR or R-CHOP as a first-line treatment and could not have undergone a stem cell transplant.

Following first-line treatment, patients were required to have lived for at least 200 days if no rituximab maintenance or second-line treatment was given, or have a gap of at least 200 days between the completion of induction therapy and the start of second-line treatment. Along with aiming to identify treatment patterns and the use of rituximab maintenance, the study examined OS, lymphoma-specific survival, and the receipt of second-line therapy.

Investigators identified 6552 patients diagnosed with MCL during the study period who were at least 66 years old at the time of diagnosis. Of those, 272 were eligible for evaluation in the real-world study.

Among all eligible patients for the real-world study, the median age was 75 years (interquartile range, 71-79), 64% of patients were male, and 94% of patients were White. Additionally, 20% of patients were considered frail, 21% had a comorbidity score of at least 3, and 46% of patients had stage III/IV disease.

Seventy-four percent of patients received BR as a first-line treatment, and 25% of patients had a first-line treatment duration of less than 130 days. Of the 272 patients, 136 received rituximab maintenance, and 136 did not.

Notably, from 2007 to 2017, rates of first-line BR increased, and rates of first-line R-CHOP decreased. Among patients treated in 2007, 32.2% received R-CHOP, compared with 1.1% who got BR. In 2010, the rates of first-line BR and R-CHOP were both 19.3%, and in all subsequent years, BR was used more than R-CHOP. By 2017, 41.1% of all patients received first-line BR, compared with 5% who were given R-CHOP.

Additional data showed that lymphoma-specific mortality was higher in patients who did not receive rituximab maintenance (subdistribution hazard ratio [sHR], 0.50; 95% CI, 0.31-0.80). Non–lymphoma-specific mortality also favored patients who received rituximab maintenance (sHR, 0.61; 95% CI, 0.29-1.28). Receipt of second-line therapy was also higher in patients who did not receive rituximab maintenance (sHR, 0.56; 95% CI, 0.39-0.81).

Reference

Di M, Long JB, Kothari SK, et al. Treatment patterns and real-world effectiveness of rituximab maintenance in older patients with mantle cell lymphoma: a population-based analysis. J Clin Oncol. 2022;40(suppl 16):7554. doi:10.1200/JCO.2022.40.16_suppl.7554