Mosunetuzumab Plus Polatuzumab Vedotin in Transplant-Ineligible Refractory/Relapsed Large B-Cell Lymphoma: Primary Results of the Phase III SUNMO Trial

Author(s): Lihua E. Budde, MD, PhD¹; Huilai Zhang, MD, PhD²; Won-Seog Kim, MD, PhD³; Dai Maruyama, MD, PhD⁴; Eduardo M. Rego, MD, PhD⁵; Lalita Norasetthada, MD⁶; Huangming Hong, MD⁷; Muhit Ozcan, MD⁸; Young-Woo Jeon, MD, PhD⁹; Danielle Leão Cordeiro de Farias, MD, MSc, MBA¹⁰; Laura Maria Fogliatto, MD, PhD¹¹; Astrid Pavlovsky, MD¹²; Hideki Goto, MD, PhD¹³; Adam J. Olszewski, MD¹⁴; Nikesh Shah, MD¹⁵; Bei Hu, MD¹⁶; Shen Yin, PhD¹⁷; Hao Wu, PhD¹⁷; Iris To, PharmD¹⁷; Wahib S. Ead, PharmD¹⁷; Joan Ashby, MSc¹⁷; Martin Janousek, PharmD¹⁸; Song Pham, MSc¹⁹; Jue Wang, PhD¹⁷; Antonia Kwan, MD, PhD¹⁷; Connie L. Batlevi, MD, PhD¹⁷; Michael C. Wei, MD, PhD¹⁷; Jason Westin, MD, MS, FACP, FASCO²⁰;

Source: DOI: 10.1200/JCO-25-01957

Dr. Maen Hussein's Thoughts

Median progression-free survival (PFS) was significantly longer with mosunetuzumab plus polatuzumab vedotin (Mosun-Pola) than with R-GemOx (11.5 months vs 3.8 months). The overall response rate (ORR) was significantly higher with Mosun-Pola compared with R-GemOx (70% vs 40%; P < .0001), with complete response rates of 51% and 24%, respectively. Cytokine release syndrome (CRS) occurred in fewer than 5% of patients.

PURPOSE

Prognosis for patients with refractory/relapsed large B-cell lymphoma (LBCL) considered ineligible for curative-intent therapy is poor. The combination of mosunetuzumab, a T-cell–engaging bispecific antibody, and polatuzumab vedotin, an antibody-drug conjugate (Mosun-Pola), represents a novel fixed-duration outpatient therapy.

METHODS

In the phase III SUNMO trial, patients with refractory/relapsed LBCL who were ineligible for autologous stem-cell transplant were randomly assigned (2:1) to receive Mosun-Pola or rituximab, gemcitabine, and oxaliplatin (R-GemOx). Dual primary end points were centrally assessed overall response rate (ORR) and progression-free survival (PFS). Overall survival was a key secondary end point.

RESULTS

A total of 208 patients were randomly assigned to receive Mosun-Pola (n = 138) or R-GemOx (n = 70). a median follow-up of 23.2 months, the primary analysis of SUNMO demonstrated that the median PFS was significantly longer with Mosun-Pola than with R-GemOx (11.5 months [95% CI, 5.6 to 18] v 3.8 months [95% CI, 2.9 to 4.1]; hazard ratio for progression or death, 0.41 [95% CI, 0.3 to 0.6]; P < .0001). ORR was significantly greater with Mosun-Pola versus R-GemOx (70% v 40%; P < .0001), with complete response rates of 51% and 24%, respectively. In the Mosun-Pola group, the rate of grade ≥2 cytokine release syndrome (CRS) and usage of tocilizumab occurred in

CONCLUSION

Mosun-Pola demonstrated superior efficacy versus R-GemOx, with significant improvements in both ORR and PFS, and infrequent CRS events with a manageable safety profile.

Author Affiliations

¹City of Hope, Duarte, CA; ²Tianjin Medical University Cancer Institute, Tianjin, China; ³Samsung Medical Center, Seoul, Republic of Korea; ⁴Cancer Institute Hospital, Japanese Foundation for Cancer Research, Tokyo, Japan; ⁵Instituto D'Or de Pesquisa e Ensino, São Paulo, Brazil; ⁶Chiang Mai University, Chiang Mai, Thailand; ⁷Si Chuan Cancer Hospital, Chengdu, China; ⁸Ankara University School of Medicine, Ankara, Turkey; ⁹Yeouido St Mary's Hospital, Seoul, Republic of Korea; ¹⁰Hospital Beneficência Portuguesa de São Paulo, São Paulo, Brazil; ¹¹Hospital de Clínicas de Porto Alegre, Porto Alegre, Brazil; ¹²Fundaleu, Buenos Aires, Argentina; ¹³Department of Hematology, Hokkaido University Hospital, Sapporo, Japan; ¹⁴Brown University, Providence, RI; ¹⁵Tampa General Hospital Cancer Institute, Tampa, FL; ¹⁶Atrium Health Levine Cancer Institute and Wake Forest School of Medicine, Charlotte, NC; ¹⁷Genentech, Inc, South San Francisco, CA; ¹⁸F. Hoffmann-La Roche Ltd, Basel, Switzerland; ¹⁹Hoffmann-La Roche Ltd, Mississauga, ON, Canada; ²⁰MD Anderson Cancer Center, Houston, TX

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