CMV-TCIP Directed Letermovir Prophylaxis After Allo-SCT

Inclusion Criteria:

* ≥ 18 years of age on the day of signing informed consent.
* Karnofsky performance \>70%
* Have documented seropositivity for CMV (either donor or recipient CMV IgG seropositivity) before AHCT.
* Eligible for AHCT from an HLA-matched related, matched unrelated, mismatched unrelated or haploidentical donor using either bone marrow or peripheral blood stem cells.
* Have undetectable CMV DNA from a plasma sample collected within 5 days prior to enrollment.
* Must be within Day-10 thru Day+28 days of planned HSCT at the time of enrollment.
* Be able to comply with medical recommendations or follow-up.
* Has adequate organ functions determined by

  1. Serum creatinine clearance ≥50 ml/min (calculated with Cockroft-Gault formula).
  2. Bilirubin ≤1.5 mg/dl except for Gilbert's disease.
  3. ALT or AST ≤200 IU/ml for adults.
  4. Conjugated (direct) bilirubin \< 2x upper limit of normal.
  5. Left ventricular ejection fraction ≥40%.
  6. Diffusing capacity for carbon monoxide (DLCO) ≥ 50% predicted corrected for hemoglobin.

Exclusion Criteria:

* Has a history of CMV end-organ disease or CS-CMVi within 6 months prior to enrollment.
* Received within 7 days prior to screening or plans to receive during the study any of the following:

  1. Ganciclovir
  2. Valganciclovir
  3. Foscarnet
  4. Acyclovir (\> 3200 mg PO per day or \> 25 mg/kg IV per day)
  5. Valacyclovir (\> 3000 mg/day)
  6. Famciclovir (\> 1500 mg/day)
* Received within 30 days prior to screening or plans to receive during the study any of the following drugs: cidofovir, CMV hyper-immune globulin, any investigational CMV antiviral agent/biologic therapy.
* Has suspected or known hypersensitivity to active or inactive ingredients of letermovir formulations.
* Has an uncontrolled infection
* Requires mechanical ventilation or is hemodynamically unstable