Plain language summary of the management of certain side effects of teclistamab in people with multiple myeloma

Plain Language SummaryWhat is this summary about?This summary describes management of two side effects in the MajesTEC-1 clinical study, which tested the cancer drug teclistamab in participants with multiple myeloma. These side effects were cytokine release syndrome (CRS) and infections.What were the results?In the MajesTEC-1 study, 63% of participants had their multiple myeloma improve; 72% of participants developed CRS, and 80% had an infection. CRS was mostly low grade, occurred during the initial stage when participants received lower teclistamab doses, and was manageable. No participants stopped teclistamab entirely for CRS. Participants taking teclistamab had several types of infections. Some participants receiving teclistamab had low levels of immune cells and antibodies, which help the body fight infections. People with multiple myeloma should be screened for infections. Ongoing infections should be completely resolved before receiving teclistamab.What do these results mean?Most MajesTEC-1 study participants had their multiple myeloma respond to teclistamab treatment. People receiving teclistamab should be aware of the risk of developing CRS and infections and report symptoms to their healthcare team. Healthcare teams should monitor people carefully and not give teclistamab to people with active CRS or infection.Clinical trial number: NCT04557098