Ajay K. Nooka, MD, Associate Professor of Hematology and Medical Oncology at Emory School of Medicine, discusses the updated efficacy and safety results from the phase 1/2 MajesTEC-1 study evaluating teclistamab in patients with relapsed or refractory multiple myeloma. These data were recently presented at the 2022 American Society of Clinical Oncology (ASCO) Annual Meeting and announced in a press release.

Multiple myeloma is a rare blood cancer associated with uncontrolled growth of plasma cells. Abnormal plasma cells – also known as myeloma cells – interfere with the production of healthy blood cells in the bone marrow. Symptoms of multiple myeloma may include: bone pain (particularly in the chest and spine), frequent infections, weakness or numbness in the legs, fatigue, confusion, excessive thirst, and constipation. While the disease is treatable, relapses are common and some patients are refractory to first line, and subsequent, therapies.

As Dr. Nooka explains, MajesTEC-1 is a phase 1/2 study testing teclistamab in relapsed/refractory multiple myeloma. Teclistamab is a T-cell redirecting, bispecific IgG4 antibody that targets both B-cell maturation antigen (BCMA) and CD3 receptors to induce T-cell mediated cytotoxicity of BCMA-expressing myeloma cells. 

As of March 2022, 165 patients were treated with teclistamab at the recommended subcutaneous phase 2 dose of 1.5 mg/kg preceded by step-up doses of 0.06 and 0.3 mg/kg across both phase 1 (NCT03145181) and phase 2 (NCT04557098) of the study.

Median patient age was 64 years (range 33–84). 100% were triple-class exposed, 70% were penta-drug exposed, 78% were triple-class refractory, and 30% were penta-drug refractory. Overall response rate was 64% (95% CI 56–72), with a complete response or better achieved in 30% of patients. Responses were durable and deepened over time; median duration of response was not reached. The 12-month durability of response rate was 66% (95% CI 49–79). The majority of patients who responded to treatment in the first cycle had a reduction in soluble BCMA. 

The most common hematologic adverse events were neutropenia, anemia, thrombocytopenia, and lymphopenia.  Infections occurred in 63% of patients. The most common nonhematologic adverse event was cytokine release syndrome; with a median time to onset of 2 days and median duration of 2 days. There were no treatment-related deaths. No patients required a reduction in teclistamab dose due to adverse events.

Overall, at approximately 9 months of follow-up, data from this study reaffirm the deep and durable responses that have been observed with teclistamab in highly refractory multiple myeloma patients, with no new safety signals.

To learn more about multiple myeloma and other rare cancers, visit https://checkrare.com/diseases/cancers/