Is there a role for secondary CMV prophylaxis in solid organ transplant patients?

I do not think that secondary prophylaxis (SP) should be used routinely in solid organ transplant patients (SOTPs) after an episode of CMV disease. There is a fairly good retrospective study of SP with Valganciclovir (VGCV) that found no real benefit (Gardiner et al., PMID 29020220). There are some newer suggestions that letermovir (LMV) may be an option (Saullo & Miller, PMID 36332639) because it doesn't cause cytopenias and is approved for primary prophylaxis, but I am unaware of high-quality data in SOTPs that this is an effective strategy. All that being said, there are some situations where physicians may want to use SP for a short time or perhaps consider routine CMV monitoring (weekly CMV PCR) if the patient is able to reliably get labs and you have a good system in place to respond to those labs. For instance, If the patient recently had a rejection episode accompanied by immunosuppression intensification, then SP could be used until the immunosuppression returns to baseline. So in summary, I do not think SP should be routine practice, but one can consider using it in specific scenarios where the potential short-term benefits of preventing a CMV reactivation in the next few weeks to months outweigh the potential risks/costs.