Hi everyone,
This study was recently published. I thought it might be of interest to patients being treated with Darzalex, or about to start treatment with the drug.
Keep in mind that this is a single-institution study with a small number of patients. Also, according to the abstract, the infections that were observed occurred only in patients who experienced only a partial response (PR) or worse. So patients who respond well to the drug may be less likely to develop an infection.
Link to article:
Nahi, H., et al, "Infectious complications and NK cell depletion following daratumumab treatment of multiple myeloma," PLoS One. Feb 13, 2019 (full text of article)
Abstract:
Treatment with daratumumab (dara), a monoclonal anti-CD38 antibody of IgG1 subtype, is effective in patients with multiple myeloma. However, dara also impairs the cellular immunity, which in turn may lead to higher susceptibility to infections. The exact link between immune impairment and infectious complications is unclear. In this study, we report that nine out of 23 patients (39%) with progressive multiple myeloma had infectious complications after dara treatment. Five of these patients had viral infections, two developed with bacterial infections and two with both bacterial and viral infections. Two of the viral infections were exogenous, i.e. acute respiratory syncytial virus (RSV) and human metapneumovirus (hMPV), while five consisted of reactivations, i.e. one herpes simplex (HSV), 1 varicella-zoster (VZV) and three cytomegalovirus (CMV). Infections were solely seen in patients with partial response or worse. Assessment of circulating lymphocytes indicated a selective depletion of NK cells and viral reactivation after dara treatment, however this finding does not exclude the multiple components of viral immune-surveillance that may get disabled during this monoclonal treatment in this patient cohort. These results suggest that the use of antiviral and antibacterial prophylaxis and screening of the patients should be considered.