A new type of immunotherapy—chimeric antigen receptor (CAR) T-cell therapy targeting B-cell maturation protein (BCMA)—may be a new effective type of treatment for patients with multiple myeloma, according to the results of a single-arm study (abstract LBA3001) presented at the 2017 American Society of Clinical Oncology (ASCO) Annual Meeting, held June 2–6.
“Our results show clinical and reproducible therapeutic efficacy in refractory or relapsed multiple myeloma disease,” said Wanhong Zhao, MD, PhD, an associate director of hematology at the Second Affiliated Hospital of Xi’an Jiaotong University in China, who presented the results.
With longer than 1 year of follow-up, early patients enrolled on the study are showing durable and stringent complete remissions, according to Zhao.
In recent years, CAR T-cell therapy targeting CD19 has been shown to be very effective in trials of acute lymphoblastic leukemia. However, there had been little success with CAR T-cell therapy targeting other biomarkers in other types of cancer.
Zhao and colleagues conducted a single-arm trial to assess the safety and efficacy of this treatment approach in patients with multiple myeloma. The presentation included data from the first 35 patients enrolled in the ongoing trial.
The overall response rate was 100%; 33 of the 35 patients (94%) had clinical remission of myeloma, with either complete response or very good partial response occurring within 2 months of undergoing CAR T-cell therapy. First signs of efficacy appeared as early as 10 days after treatment initiation.
Of the 35 patients, 19 have been followed for longer than 4 months. Of these patients, 14 have reached stringent complete response, 4 patients have achieved very good partial response, and 1 patient has achieved partial response.
In addition, there are 5 patients who have been followed for longer than 1 year; all of these patients remain in stringent complete remission and are free of minimal residual disease.
Cytokine release syndrome (CRS) is a common adverse effect related to CAR T-cell therapy. CRS occurred in 85% of patients. Among the 35 patients, 6 patients remained free of any CRS; 17 had grade 1, 10 had grade 2, and 2 had grade 3. No grade 4 or 5 CRS occurred and there were no treatment-related deaths.
According to Zhao, a US clinical trial of this technology is currently underway.
Commenting on the results of this study, ASCO Expert Michael S. Sabel, MD, FACS, of the University of Michigan, said that these results were revolutionary and show that immunotherapy is beginning to provide hope to patients with cancers that are not responding to standard chemotherapy.
“You are now seeing a merger of immunotherapy with precision therapy and this is the epitome of personalized medicine,” Sabel said. “Now you see the ability to combine personalized medicine and immunotherapy to gear T cells to recognize patients’ own specific tumor. This opens the door to using precision immunotherapy to expand the potential of immunotherapy to a wider net of patients.”