Monoclonal Antibody Shows Promise in Aggressive R/R Adult T-cell Leukemia/Lymphoma
Mogamulizumab induced an encouraging response rate in patients with relapsed/refractory adult T-cell leukemia/lymphoma.
CHICAGO — Mogamulizumab induced an encouraging response rate in patients with relapsed/refractory adult T-cell leukemia/lymphoma compared with chemotherapy, researchers reported at the 2016 American Society of Clinical Oncology (ASCO) Annual Meeting.1
"There is no standard first-line treatment for adult T-cell leukemia/lymphoma," said lead study investigator Adrienne A. Phillips, MD, MPH, assistant professor of clinical medicine at Weill Cornell Medicine and New York-Presbyterian Hospital. "There are no approved treatments in the first- or second-line outside of Japan. Adult T-cell leukemia/lymphoma patients have been largely excluded from pivotal studies of other T-cell lymphoma drugs."
Mogamulizumab is a monoclonal antibody directed against CC chemokine receptor 4 (CCR4), which is expressed in more than 90% of patients with adult T-cell leukemia/lymphoma. It is approved in Japan for the treatment of patients with CCR4-positive adult T-cell leukemia/lymphoma, peripheral T-cell lymphoma, and cutaneous T-cell lymphoma. Therefore, researchers opted to evaluate mogamulizumab in patients outside of Japan with aggressive relapsed/refractory adult T-cell leukemia/lymphoma.
For the phase 2 study, Dr Phillips and colleagues enrolled 71 patients with acute, lymphomatous, and chronic subtypes from 22 centers worldwide. Of those, 91.5% expressed CCR4.
Patients were randomly assigned 2:1 to receive mogamulizumab 1.0 mg/kg IV weekly for the first 4-week cycle and then biweekly or investigator's choice of chemotherapy (gemcitabine-oxaliplatin [GEMOX]; dexamethosone, high-dose cytabarine, and cisplatin [DHAP]; or pralatrexate). Patients who progressed on chemotherapy could cross over to mogamulizumab.
Objective response rate was evaluated by the treating investigator and in blinded fashion by independent review.
The objective response rate by independent review was 28% with mogamulizumab compared with 8% with investigator's choice of chemotherapy, according to the data. The confirmed objective response rate by independent review in the mogamulizumab group was 11% vs 0 confirmed responses in the chemotherapy group.
"Median durations of confirmed response were 5.5 and 5 months for investigator assessment and independent review, respectively," Dr Phillips added.
In addition, 18 patients in the chemotherapy group received mogamulizumab upon progression, of whom 3 responded to immunotherapy.
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"Clinically significant response rates and responses after cross-over suggest clinical benefit with mogamulizumab in relapsed or refractory adult T-cell leukemia/lymphoma," Dr Phillips noted.
In terms of safety, the most common treatment-emergent adverse events reported in the study were infection, infusion-related reaction, and rash/drug eruption.
"The mogamulizumab safety profile is similar to previous experience in Japan where mogamulizumab has been approved since 2012," Dr Phillips concluded.
- Phillips AA, Fields P, Hermine O, et al. A prospective, multicenter, randomized study of anti-CCR4 monoclonal antibody mogamulizumab (moga) vs investigator's choice (IC) in the treatment of patients (pts) with relapsed/refractory (R/R) adult T-cell leukemia-lymphoma (ATL). J Clin Oncol. 2016; 34 (suppl; abstr 7501).