Impaired T cells and "memory-like" NK-cell reconstitution is linked to late-onset HCMV reactivation after letermovir cessation

Allogeneic hematopoietic stem cell transplantation (alloSCT) is the only cure for many hematologic malignancies. However, alloSCT recipients are susceptible to opportunistic pathogens, such as human cytomegalovirus (HCMV). Letermovir prophylaxis has revolutionized HCMV management, but the challenge of late HCMV reactivations has emerged. Immunological surrogates of clinically significant HCMV infection (csCMVi) after discontinuation of letermovir remain to be defined. Therefore, we studied natural killer (NK)-cell reconstitution along with the global and HCMV pp65-specific T-cell repertoire of 24 alloSCT recipients at 7 time points before (day +90) and after (days +120-270) cessation of letermovir prophylaxis. Patients who experienced csCMVi had lower counts of IFN-

• Lauruschkat, C. D.
• Muchsin, I.
• Rein, A. F.
• Erhard, F.
• Grathwohl, D.
• Dölken, L.
• Köchel, C.
• Nehmer, A.
• Falk, C. S.
• Grigoleit, G. U.
• Einsele, H.
• Wurster, S.
• Kraus, S.