Prevymis Dosage/Direction for Use

General: PREVYMIS Tablets: Administer with or without food.
Swallow tablets whole. Do not divide, crush or chew. 
PREVYMIS tablet and concentrate for solution for infusion may be used interchangeably at the discretion of the physician, and no dose adjustment is necessary.
Missed Dose: Instruct patients that if they miss a dose of PREVYMIS, they should take it as soon as they remember. If they do not remember until it is time for the next dose, instruct them to skip the missed dose and go back to the regular schedule. Instruct patients not to double their next dose or take more than the prescribed dose.
Recommended Dosage in Adults: The recommended dosage of PREVYMIS is 480 mg administered once daily.
PREVYMIS should be started after HSCT. PREVYMIS may be started on the day of transplant and no later than 28 days post-transplant. PREVYMIS may be started before or after engraftment. Continue PREVYMIS through 100 days post-transplant.
The safety and efficacy of letermovir use for more than 100 days has not been studied in clinical trials.
Dosage Adjustment in Adults: If PREVYMIS is co-administered with cyclosporine, the dosage of PREVYMIS should be decreased to 240 mg once daily [see Table 6 in Established and Other Potential Drug Interactions under INTERACTIONS].
If cyclosporine is initiated after starting PREVYMIS, the next dose of PREVYMIS should be decreased to 240 mg once daily.
If cyclosporine is discontinued after starting PREVYMIS, the next dose of PREVYMIS should be increased to 480 mg once daily.
If cyclosporine dosing is temporarily interrupted due to high cyclosporine levels, no dose adjustment of PREVYMIS is needed.
Pediatric Patients: Safety and efficacy of PREVYMIS have not been established in pediatric patients less than 18 years of age.
Geriatric Patients: No dose adjustment of PREVYMIS is required based on age [see Use in Elderly under PRECAUTIONS].
Renal Impairment: No dose adjustment of PREVYMIS is required based on renal impairment [see Hepatic Impairment as follows, Renal Impairment under PRECAUTIONS].
Hepatic Impairment: No dose adjustment of PREVYMIS is required based on mild (Child-Pugh Class A) to moderate (Child-Pugh Class B) hepatic impairment. PREVYMIS is not recommended for patients with severe (Child-Pugh Class C) hepatic impairment.
PREVYMIS is not recommended in patients with moderate hepatic impairment combined with moderate or severe renal impairment [see Hepatic Impairment under PRECAUTIONS].