Concomitant Administration of posaconazole and isavuconazole with Letermovir: Clinical and Pharmacological Considerations.

We sought in this case-control retrospective study to compare posaconazole/isavuconazole (PCZ/IVC)-Ctrough in high-risk allogeneic hematopoietic cell transplant (HCT) recipients who received letermovir (LET) or not. PCZ/IVC-Ctrough were not found to be significantly different between cases and controls: 1.31 mg/l (median) (0.90; IQR) vs 1.36 mg/l (1.16) (P-value: 0.31) and 3.20 mg/l (2.40) vs 2.35 mg/l (1.50) (P-value: 0.17), respectively. In conclusion, we observed PCZ/IVC-Ctrough levels within the expected range and no significant effect of LET co-administration.