LUGANO, SWITZERLAND – Combining lenalidomide (Revlimid) with an anti-CD19 monoclonal antibody labeled MOR208 showed promising activity in patients with relapsed or refractory diffuse large B-cell lymphoma (DLBCL) who were ineligible for stem cell transplant and had poor prognosis, early interim results from a clinical study indicate.
Among 34 patients evaluable for response, the preliminary objective response rate (ORR) was 56%, including complete responses in 32% of patients, reported Gilles Salles, MD, PhD, of the University of Lyon, France.
Dr. Gilles Salles
MOR208 is a humanized anti-CD19 monoclonal antibody with the Fc-antibody region enhanced to improve cytotoxicity. Its mechanisms of action include natural killer cell–mediated antibody-dependent cell-mediated cytotoxicity, antibody-dependent cellular phagocytosis, and direct cytotoxicity.
In a preclinical study, a combination of MOR208 and lenalidomide showed synergistic antileukemic and antilymphoma activity both in vivo and in vitro, Dr. Salles said.
In addition, both lenalidomide and MOR208 have shown significant activity against relapsed, refractory B-cell non-Hodgkin lymphomas.
In an ongoing phase II, open-label study, Dr. Salles and his colleagues are enrolling transplant-ineligible patients 18 years and older with relapsed/refractory DLBCL, Eastern Cooperative Oncology Group status 0-2, and adequate organ function who had disease progression after 1-3 prior lines of therapy.
Patients with primary refractory DLBCL, double-hit or triple-hit DLBCL (i.e., mutations in Myc, BCL2, and/or BCL6), other NHL histological subtypes, or central nervous system lymphoma involvement are excluded.
Patients receive MOR208 12 mg/kg intravenously on days 1, 8, 15, and 22 for cycles 1-3 and on days 1 and 15 of cycles 4-12. Lenalidomide 25 mg orally is delivered on days 1-21 of each cycle. Patients who have stable disease or better at the end of 12 cycles can be maintained on MOR208 at the same dose on days 1 and 15.
As of the data cutoff on March 6, 2017, 44 patients had been enrolled, and 34 were evaluable for response. The median patient age was 73 years (range, 47-82 years).
At the time of the data presentation, ORR, the primary endpoint, was 56%, consisting of 32% complete responses (11 patients), 24% partial responses (8), 12% stable disease (4), and 32% of patients who either had disease progression or had not yet had a postbaseline response assessment.
The median time to response was 1.8 months, with a median time to complete response of 3.4 months. Of 19 responders, 16 continue to have a response, including 10 of 11 patients with complete responses.
The most common grade 3 or 4 hematologic toxicities were neutropenia, anemia, and thrombocytopenia. Nonhematologic toxicities of any grade included rashes in 20% of patients, pyrexia in 16%, diarrhea in 16%, asthenia in 14%, and pneumonia, bronchitis, and nausea in 11% each.
There were no reported infusion-related reactions with the antibody. In all, 27% of patients required a lenalidomide dose reduction – to 20 mg/day in 20% of patients and to 15 mg/day in 7%.
Study accrual, follow-up of patients on therapy, investigations of cell origin, and subgroup analyses are ongoing.
MorphoSys is sponsoring the study. Dr. Salles has received honoraria from Amgen, BMS, Celgene, Gilead, Janssen, Roche/Genentech, and Servier and is an advisor/consultant to many of the same companies.