Chronic Myeloid Leukemia in Children: Immune Function and Vaccinations

Abstract

Children with CML need TKI treatment for many years, and the lack of knowledge about immune dysfunction with TKI has hindered routine immunizations. This review attempts to provide an overview of the effects of TKIs licensed for children (e.g., imatinib, dasatinib, and nilotinib) on immune function, as well as its implications on immunizations. We discuss surveillance strategies (e.g., immunoglobulin blood serum levels and hepatitis B reactivation) and immunizations. All inactivated vaccines (e.g., influenza, pneumococcal, and streptococcal) can be given during the treatment of CML in the chronic phase, although their efficacy may be lower. As shown in single cases of children and adults with CML, live vaccines (e.g., varicella, measles, mumps, rubella, and yellow fever) may be administered under defined circumstances with great precautions. We also highlight important aspects of COVID-19 in this patient population (e.g., the outcome of COVID-19 infection in adults with CML and in children with varying hemato-oncological diseases) and discuss the highly dynamic field of presently available different vaccination options. In conclusion, TKI treatment for CML causes humoral and cellular immune dysfunction, which is mild in most patients, and thus infectious complications are rare. Routine immunizations are important for health maintenance of children, but vaccinations for children with CML on TKI therapy should be carefully considered.

Infectious Complications of Targeted Therapies in Children with Leukemias and Lymphomas

“…Although the data are scarce, a window for live attenuated vaccination can be created in children with CML receiving TKIs by temporarily interrupting the therapy. Despite the concerns for the safety of vaccines that contain live attenuated viruses, preliminary experience supports the safety of MMR vaccine administration, while indications of COVID-19 vaccination for children with CML do not differ from those for the general pediatric population [ 137 ].…”

Alterations in cellular metabolisms after TKI therapy for Philadelphia chromosome-positive leukemia in children: A review

“…In recent years, the way to manage tumor patients has significantly changed as a result of tumor immunotherapy ( 132 ). During the treatment, TKIs do not only target BCR-ABL1 but also inhibit additional targets such c-KIT, TEC, SRC, FLT3, Lck, and mitogen-activated kinases (MAPK) ( 133 ). This “off-target” effect can alter immune responses, both harmful and beneficial.…”