Spanish researchers reveal why vaccines have lower efficacy in patients with multiple myeloma

A research carried out by a group from Cima and the Clínica Universidad de Navarra has described the composition of the immune system in blood samples from patients with multiple myeloma, by generating a new immunological atlas, and has revealed how changes in immune cells themselves can influence the efficacy of vaccines such as that against COVID-19.

Multiple myeloma is a type of cancer characterized by an uncontrolled growth of a subset of immune cells - plasma cells -, which promotes immune changes that make patients more susceptible to infections, their main cause of death.

Based on this, the study, developed at the Cancer Center Clínica Universidad de Navarra and led by Dr. Esperanza Martín-Sánchez and Dr. Bruno Paiva, has analyzed blood samples from 28 patients with multiple myeloma and has compared them with those from 96 healthy individuals. The results, published in the high-impact scientific journal Blood Cancer Journal, have confirmed alterations in the composition of immune cells, especially in T and B lymphocytes.

In addition, when these data were compared with those of 53 patients with other tumors that affect B-lymphocyte production, the researchers observed that multiple myeloma is associated with a more severe immune suppression. "This new atlas of the immune system in patients with multiple myeloma is fundamental to understand how this disease affects the responsiveness of the defense system," as explained by Dr. Esperanza Martín-Sánchez, researcher in the Hemato-Oncology Program at Cima and first author of the publication.

On the other hand, the scientists also analyzed how the altered immune system of multiple myeloma patients responds to COVID-19 vaccination. These data complement previous results published in 2022 by the same group, which confirmed that the efficacy of COVID-19 vaccine could be lower in patients with hematological tumors.

"Due to immunological changes, vaccine administration to these patients may not have the same efficacy as in the healthy population. It is therefore important to know how their immune system is affected in order to establish specific actions to effectively prevent the risk of infections," Dr. Martín-Sánchez points out.

Dr. Bruno Paiva, co-director of the Hemato-Oncology Program at Cima, suggests that "our findings will allow us to develop more personalized and effective programs to vaccinate and prevent infections for these patients. For instance, we will be able to find the most appropriate vaccination timing for them, which will be when their defense system is less altered and, then, more likely to generate an adequate immune response".
 
A less invasive method for the patient

One of the key aspects of this study is that immune composition has been depicted in blood samples. Dr. Martín-Sánchez explains that "the benefit of studying blood samples is twofold. Firstly, they provide essential information on the patient's immune status, since they act as a mirror of the bone marrow; and, secondly, they are obtained through a minimally invasive method. So far, most studies have analyzed bone marrow samples, because it is where blood cells are produced and the usual niche for tumor plasma cells. However, obtaining these samples requires a bone marrow aspirate, which in many cases is painful for the patient".

The research has been developed with the participation of the Basque-Navarre Association of Hematology and Hemotherapy in collaboration with several scientific groups of the Centro de Investigación Biomédica en Red (CIBERONC). It has also received funding from various public and private entities, including Iberdrola (through the Spanish Association Against Cancer), Cancer Research UK and the CRIS Cancer Foundation.

Caption: Scientific group from Cima and the Clínica Universidad de Navarra that carried out the research.

Reference:

Martín-Sánchez, E., Tamariz-Amador, LE., Guerrero, C. et al. Immune dysfunction prior to and during vaccination in multiple myeloma: a case study based on COVID-19. Blood Cancer J. 14, 111 (2024). https://doi.org/10.1038/s41408-024-01089-5