Multiple myeloma (MM) and chronic lymphocytic leukemia (CLL) patients have increased morbidity and mortality rates of COVID‐19 due to immunosuppression associated with the disease and ongoing therapy. The same immune impairment accompanying CLL and MM also affects suboptimal vaccine response. The study assessed the effectiveness of the humoral and T cell‐mediated immunity following mRNA COVID‐19 vaccination (using either BNT162b2 or mRNA‐1273) in short‐term (2‐5 weeks after second dose) and long‐term follow‐up (12 weeks after vaccination). Between March and August 2021, blood samples were obtained from 62 CLL and 60 MM patients from eight different hematology departments in Poland. Total anti‐RBD antibodies were detected in 37% MM patients before vaccination, increased to 91% and 94% in short‐ and long‐term follow‐up, respectively. In CLL, serological responses were detectable in 21% of patients before vaccination and increased to 45% in the short‐term and 71% in long‐term observation. We detected a tendency to higher frequencies of specific CD8+ T cells against SARS‐CoV‐2 after vaccination compared to samples before vaccination in MM patients and no changes in frequencies of specific T cells in CLL patients. Our study provides novel insights into mRNA vaccination efficacy in immunocompromised MM and CLL patients, and our findings highlight that specific CD8+ T cells against SARS‐CoV‐2 might be induced by vaccination but do not correlate positively with serological responses.

Although the outcome has improved over the past decades, due to improved supportive care, a better understanding of risk factors, and intensified chemotherapy, pediatric acute myeloid leukemia remains a life-threatening disease, and overall survival (OS) remains near 70%. According to French-American-British (FAB) classification, AML is divided into eight subtypes (M0–M7), and each is characterized by a different pathogenesis and response to treatment. However, the curability of AML is due to the intensification of standard chemotherapy, more precise risk classification, improvements in supportive care, and the use of minimal residual disease to monitor response to therapy. The treatment of childhood AML continues to be based primarily on intensive, conventional chemotherapy. Therefore, it is essential to identify new, more precise molecules that are targeted to the specific abnormalities of each leukemia subtype. Here, we review abnormalities that are potential therapeutic targets for the treatment of AML in the pediatric population.

No abstract