A multicenter phase 2 study of pomalidomide plus dexamethasone in patients with relapsed and refractory multiple myeloma: the Japanese MM-011 trial

A multicenter phase 2 study of pomalidomide plus dexamethasone in patients with relapsed and refractory multiple myeloma: the Japanese MM-011 trial

Experimental Hematology & Oncology, April 2016

27096106

Tatsuo Ichinohe, Yoshiaki Kuroda, Shinichiro Okamoto, Kosei Matsue, Shinsuke Iida, Kazutaka Sunami, Takuya Komeno, Kenshi Suzuki, Kiyoshi Ando, Masafumi Taniwaki, Kensei Tobinai, Takaaki Chou, Hitomi Kaneko, Hiromi Iwasaki, Chie Uemura, Hiromi Tamakoshi, Mohamed H. Zaki, Thomas Doerr, Shotaro Hagiwara

The immunomodulatory agent pomalidomide in combination with low-dose dexamethasone has demonstrated efficacy and safety for the treatment of relapsed and refractory multiple myeloma (RRMM) in phase 2 and 3 trials. However, these trials enrolled very few Asian patients. This phase 2 study investigated pomalidomide plus low-dose dexamethasone in 36 Japanese patients with RRMM after ≥2 prior therapies. Patients enrolled in the study had a relatively high disease burden (81 % Durie-Salmon stage II or III) and were heavily pretreated (median, 6.5 prior antimyeloma regimens). The overall response rate was 42 % (1 patient with complete response and 14 with partial response), with an additional 44 % (16 patients) achieving stable disease (SD). Response rates in patients aged ≤65 years and >65 years were 47 and 35 %, respectively. None of the five patients with extramedullary disease achieved a response, with three of them maintaining SD of short duration. Median progression-free survival was 10.1 months after a 7.7-month median follow-up, and the median overall survival was not reached. The most frequent grade ≥3 adverse events (AEs) were neutropenia (64 %), anemia (42 %), and thrombocytopenia (31 %). The most frequent nonhematologic grade ≥3 AEs were pneumonia and decreased appetite (8 % each). Adverse events in patients aged >65 years were similar to those in patients aged ≤65 years, except for a higher rate of grade ≥3 pneumonia. Collectively, the results of this study demonstrate that pomalidomide plus low-dose dexamethasone is an effective and safe treatment for Japanese patients with RRMM, although careful attention needs to be paid to serious infections. Clinicaltrials.gov NCT02011113.