Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
Clinical Trial
. 2025 Feb;30(2):389-396.
doi: 10.1007/s10147-024-02662-5. Epub 2024 Dec 9.

Efficacy and safety of mosunetuzumab monotherapy for Japanese patients with relapsed/refractory follicular lymphoma: FLMOON-1

Hideki Goto  1   2 , Takahiro Kumode  3 , Yuko Mishima  4 , Keisuke Kataoka  5 , Yoshiaki Ogawa  6 , Nobuhiro Kanemura  7 , Kazuyuki Shimada  8 , Toshiki Uchida  9 , Yukano Kuroe  10 , Atsuko Kawasaki  10 , Jotaro Sato  10 , Takanori Teshima  11   12
Affiliations
Clinical Trial

Efficacy and safety of mosunetuzumab monotherapy for Japanese patients with relapsed/refractory follicular lymphoma: FLMOON-1

Hideki Goto et al. Int J Clin Oncol. 2025 Feb.

Abstract

Background: In a global phase I/II study (GO29781; NCT02500407), single-agent mosunetuzumab had a manageable safety profile and induced durable complete responses in patients with relapsed/refractory (R/R) B-cell non-Hodgkin lymphoma, including in patients with R/R follicular lymphoma (FL). In this analysis, the efficacy and safety of mosunetuzumab monotherapy were evaluated in an expansion cohort, FLMOON-1, in Japanese patients with R/R FL who had received ≥ 2 prior lines of therapy in a phase I study (JO40295, jRCT2080223801).

Methods: Mosunetuzumab was administered intravenously at the recommended phase II dose (with cycle 1 step-up dosing) for eight cycles or up to 17 cycles, or until disease progression or unacceptable toxicity. The pre-specified primary endpoint was Independent Review Facility (IRF)-assessed complete response rate (CRR; as best overall response). Secondary objectives included investigator (INV)-assessed CRR, INV- and IRF-assessed objective response rate (ORR), and safety.

Results: At the data cutoff (October 13, 2023), 19 patients (median age 72 years) were evaluated. The IRF-assessed CRR and ORR were 68.4% and 78.9%, respectively; the INV-assessed CRR and ORR were 63.2% and 84.2%, respectively. Grade 3-4 adverse events (AEs) were observed in 89.5% of patients, with a low incidence of AEs leading to mosunetuzumab discontinuation (10.5%) and one fatal AE unrelated to mosunetuzumab. Cytokine release syndrome occurred in 47.4% of patients and were mostly Grade 1 in severity.

Conclusion: These findings indicate mosunetuzumab has a consistent efficacy and manageable safety profile in Japanese patients with R/R FL compared with previously reported data from the global phase I/II study.

Keywords: Administration; Antibodies; Bispecific; Follicular; Intravenous; Japan; Lymphoma; Non-Hodgkin.

PubMed Disclaimer

Conflict of interest statement

Declarations. Conflict of interest: HG has received Honoraria/fees from Chugai, Novartis, BMS, Gilead and AbbVie and research funding from Kyowa-Kirin, BMS, Symbio and Sanofi. TK has received Lecture/Honoraria fees from Ono Pharmaceutical and Janssen. YM has received Lecture/Honoraria fees from Chugai Pharma and F. Hoffmann-La Roche Ltd; Research grants from BMS and Eizai. KK has received annual profit from shares from Asahi Genomics; Lecture/Honoraria funding from Novartis, Chugai Pharmaceutical, and Meiji Seika Pharma; research funding from Otsuka Pharmaceutical, Chordia Therapeutics, Chugai Pharmaceutical, Takeda Pharmaceutical, and Meiji Seika Pharma; research grants from Eisai, Kyowa Kirin, Otsuka Pharmaceutical, Chugai Pharmaceutical, Mochida Pharmaceutical, JCR Pharmaceuticals, and Asahi Kasei Pharma. YO has received Lecture/Honoraria fees from Novartis; research funding from Novartis, Janssen, AbbVie, Chugai, Otsuka Pharmacue Tical and IQVIA; research grant from Mochida Pharmaceutical. NK has nothing to declare. KS has nothing to declare. TU has nothing to declare. YK is an employee of Chugai. AK is an employee of Chugai. JS is an employee of Chugai. TT has received research funds and research grants from Chugai. Ethical approval: The protocol was approved by the relevant institutional review boards. The trial was conducted in accordance with the Declaration of Helsinki, the International Conference on Harmonization guidelines for Good Clinical Practice, and applicable laws and regulations. All patients provided written informed consent.

Figures

Fig. 1
Fig. 1
Best percentage change from baseline in tumor SPD. This waterfall plot shows the best overall change in the size of tumor target lesions according to the mosunetuzumab doses received with best overall response. Plots of the best percentage changes in the SPD of target lesions are shown. aPatient with prior-CAR-T. bTwo patients out of 19 had no tumor assessment after baseline evaluation and were excluded from the analysis. CR complete response, PD progressive disease, PR partial response, SPD sum of product diameters
Fig. 2
Fig. 2
Time from first treatment with mosunetuzumab. aTwo patients out of 19 had no tumor assessment after baseline evaluation and were excluded from the analysis. PD progressive disease
See this image and copyright information in PMC

References

    1. Freedman A, Jacobsen E (2020) Follicular lymphoma: 2020 update on diagnosis and management. Am J Hematol 95(3):316–327 - PubMed
    1. Chihara D, Ito H, Matsuda T et al (2014) Difference in incidence and trends of haematological malignancies in Japan and the United States. Br J Haematol 164(4):536–545 - PMC - PubMed
    1. Muto R, Miyoshi H, Sato K et al (2018) Epidemiology and secular trends of malignant lymphoma in Japan: analysis of 9426 cases according to the World Health Organization classification. Cancer Med 7:5843–5858 - PMC - PubMed
    1. Batlevi CL, Sha F, Alperovich A et al (2020) Follicular lymphoma in the modern era: survival, treatment outcomes, and identification of high-risk subgroups. Blood Cancer J 10(7):74 - PMC - PubMed
    1. Izutsu K (2019) JSH practical guidelines for hematological malignancies, 2018: II. Lymphoma-1. Follicular lymphoma (FL). Int J Hematol 110:11–19 - PubMed

Publication types

MeSH terms

Substances

Supplementary concepts

LinkOut - more resources