|The following article features coverage from the American Society of Hematology 2020 meeting. Click here to read more of Cancer Therapy Advisor‘s conference coverage.|
Two years of clinical trial data demonstrated potentially long-lasting activity for an investigational chimeric antigen receptor (CAR) T-cell (CAR-T) product in patients with relapsed/refractory multiple myeloma (RRMM).
The data were presented at the virtual 62nd American Society of Hematology (ASH) Annual Meeting and Exposition.
Known as CT053, the investigational CAR-T product targets B-cell maturation antigen (BCMA) and uses a fully human BCMA single-chain variable fragment.
A total of 24 patients with RRMM received the investigational product in 1 of 3 single-arm, phase 1 clinical trials conducted in China (ClinicalTrials.gov Identifier: NCT03716856, ClinicalTrials.gov Identifier: NCT03302403, and ClinicalTrials.gov Identifier: NCT03380039). Patients were heavily pretreated, having received between 2 and 11 prior lines of therapy (median, 5 prior lines of therapy).
All patients had grade 3 or worse hematological toxicity, but most recovered within 2 weeks. A total of 62.5% of patients had cytokine release syndrome (CRS), all of which was grade 1 or 2. One patient had grade 3 neurotoxicity and recovered fully.
Overall, 21 patients (87.5%) responded, which included 16 stringent complete responses (sCRs) and 3 complete responses (CRs). Responses lasted for a median of 21.8 months, and patients had a median progression-free survival of 18.8 months.
The median duration of response was nearly 1 year longer in patients who did not have extramedullary disease compared with those who did (21.8 vs 10.3 months, respectively).
Nine patients who achieved CR or sCR continue to have a response.
Study presenter Siguo Hao, MD, PhD, Xinhua Hospital Affiliated to Shanghai Jiaotong University School of Medicine, Shanghai, China, said that sufficient CAR T-cell expansion and persistence were observed.
Specifically, CAR T cells were detected as early as 1 to 7 days after infusion and expansion peaked 3 to 4 weeks after infusion. Cells persisted for a median of 161 days; the longest expansion period is 510 days and remains ongoing.
Disclosures: Some of the presenters disclosed financial relationships with the pharmaceutical industry and/or the medical device industry. For a full list of disclosures, please refer to the presentation abstract.
Read more of Cancer Therapy Advisor‘s coverage of the ASH 2020 meeting by visiting the conference page.
Hao S, Jin J, Jiang S, et al. Two-year follow-up of investigator-initiated phase 1 trials of the safety and efficacy of fully human anti-Bcma CAR T Cells (CT053) in relapsed/refractory multiple myeloma. Presented at: the 62nd American Society of Hematology (ASH) Annual Meeting and Exposition; December 5-8, 2020. Abstract 132.