
Patients with multiple myeloma (MM) benefited from a third dose of the COVID-19 vaccine, according to a letter published in Cancer Cell.
“This study is the first to comprehensively capture the immune effect of the third dose of the COVID-19 vaccine in patients with plasma cell disorders and blood cancers like [MM],” said one of the study’s lead authors, Samir Parekh, MD, director of translational research in MM at The Tisch Cancer Institute at Mount Sinai and Professor of Medicine (Hematology and Medical Oncology), and Oncological Sciences, at the Icahn School of Medicine at Mount Sinai. “It provides guidance to myeloma patients, who are at risk for severe infection because they may be immunocompromised due to the disease itself and the cancer treatment.”
Previous research showed that breakthrough infections occurred in patients with MM due to poor or no response to the normal regimen of COVID-19 vaccine, most of which were two-dose mRNA vaccines.
In this study, the researchers collected blood samples from 476 patients with plasma cell disorders over a period of 15 months and compared these samples to some collected from healthy, vaccinated health care workers.
A third dose significantly increased the level of antibodies in patients with and without prior COVID-19 infection, but levels of COVID-19-fighting antibodies in patients with MM remained below those observed in healthy people.
Of the 241 patients with MM, 28% were seronegative prior to the third dose; of these, 88% developed detectable anti-SARS-CoV-2 (S) IgG after the third dose. Of those who had measurable anti-S IgG after the second dose, anti-S IgG increased in 91% after the third dose.
After the third dose, neutralization of the wild-type virus increased in patients with MM who had minimal or no response to the standard two doses. However, neutralizing titers against the Omicron variant were still lower in these patients compared with healthy controls. Therefore, a subset of patients may remain vulnerable to SARS-CoV-2 infection.
Aleman A, Van Oekelen O, Upadhyaya B, et al. Augmentation of humoral and cellular immune responses after third-dose SARS-CoV-2 vaccination and viral neutralization in myeloma patients. Cancer Cell. 2022;S1535-6108(22)00147-7.