Most patients with relapsed or refractory primary central nervous system lymphoma (PCNSL) receiving tirabrutinib were able to receive subsequent treatment, such as MTX-based therapy, according to a post-hoc analysis.
The analysis, led by Noriko Fukuhara, MD, PhD, of the Tohoku University School of Medicine in Japan, reported the results of a three-year follow-up of ONO-4059-02, a phase I/II trial on tirabrutinib. Dr. Fukuhara and colleagues assessed the number of patients who received subsequent treatment after tirabrutinib discontinuation and their treatment types, as well as the time course of Karnofsky Performance Status (KPS) and quality of life (QoL) during treatment.
ONO-4059-02 included 44 patients with relapsed or refractory PCNSL who received tirabrutinib at a daily dose of either 320mg or 480mg under a fasted condition in 28-day cycles. Patients continued treatment until disease progression or clinically unacceptable toxicity.
Six of the 44 patients received tirabrutinib for three years, two patients continued tirabrutinib, 10 discontinued tirabrutinib but did not receive subsequent treatment, and 32 received subsequent treatment after discontinuing tirabrutinib. These subsequent treatments include systemic therapy, radiotherapy, hematopoietic stem cell transplantation (HSCT), and surgery.
Response to tirabrutinib was observed in all patient subgroups. Overall response rate (ORR) was 33.3% for patients refractory to the treatment before tirabrutinib, 33.3% for patients receiving ≥ four previous treatments, 28.6% for patients receiving HSCT, 42.9% for patients with high tumor burden, and 40% for patients with CD79B and MYD88 mutations.
Evaluating the impact of long-term tirabrutinib treatment on KPS and QoL, researchers found that baseline KPS 90-100 was “significantly associated” with long-term response (odds ratio 5.99; P=0.0289). The median baseline KPS was 80, and KPS and QoL scores were maintained during the tirabrutinib treatment.
Reference
Fukuhara N, Narita Y, Nagane M, et al. Post-hoc analysis of the final, three-year follow-up results of a phase I/II study on tirabrutinib (ONO-4059) in patients with relapsed or refractory primary central nervous system lymphoma. Abstract #4472. Presented at the 65th American Society of Hematology Annual Meeting and Exposition; December 9-12, 2023; San Diego, California.