623. Mantle Cell, Follicular, and Other Indolent B-Cell Lymphoma—Clinical Studies: Clinical studies in Waldenstrom's Macroglobulinemia, Marginal Zone Lymphoma and Hairy Cell Leukemia

Christian Buske, Alessandra Tedeschi, Judith Trotman, et al.

Authors Conclusion from the Abstract: With up to 5 years of follow-up, IR showed ongoing superiority across clinical outcomes in pts with WM regardless of genotype, prior treatment, and key pt characteristics. Patterns of response with IR were similar for both TN and previously treated pts. IR maintained a manageable safety profile, with no new safety signals identified and minimal increases in common AEs after an additional 24 months of follow-up.

Christian Buske, Meletios A Dimopoulos, Alexander Grunenberg, et al.

Authors Conclusion from the Abstract: This is the first and largest prospective randomized trial to evaluate bortezomib in combination with standard immunochemotherapy, demonstrating that B-DRC is a well-tolerated regimen which induces a high rate of major responses including deep remissions after 6 months of treatment with a 2-year PFS of 81%, independently of the mutational status of MYD88 and CXCR4. At this time point of analysis, adding Bortezomib to DRC did not induce significant differences in PFS compared to DRC alone. Future trials will have to compare chemotherapy-free approaches such as continuous treatment with BTK inhibitors with fixed duration treatments exemplified by B-DRC to understand which of the two treatment approaches offers the highest long - term sustained clinical benefit to WM patients.

Tycel J. Phillips, Paolo Corradini, Ronit Gurion, et al.

Authors Conclusion from the Abstract: BTKi-naïve patients with R/R MZL achieved rapid and durable responses with single-agent parsaclisib. Comparable efficacy was observed in patients diagnosed with nodal, extranodal, or splenic MZL. Treatment with parsaclisib was generally well tolerated without unexpected toxicities. Updated data will be presented.

Stephen Opat, Alessandra Tedeschi, Kim Linton, et al.

Authors Conclusion from the Abstract: Preliminary results of this phase 2 study suggest that zanubrutinib is active in R/R MZL, with a favorable safety profile. (NCT03846427)

Frederick Lansigan, David Jacob Andorsky, Morton Coleman, et al.

Authors Conclusion from the Abstract: Similar to findings in the overall population, R2 treatment in advanced-age patients with R/R FL and MZL resulted in encouraging efficacy, and with close attention to dose reduction there is a tolerable safety profile.

Marianna Criscuolo, Alessandro Broccoli, Eugenio Galli, et al.

Authors Conclusion from the Abstract: 2CDA is greatly effective in treating HCL, with an ORR of 83%. Early and long term adverse events were rare and easily managed: although HCL-related mortality is still possible, OS at 15 years is higher than 80%.