CMV Retinitis: What to Do When Cidofovir or Foscarnet Failed to Clear CMV Antigenemia

Clinical Scenario

This protocol addresses cytomegalovirus (CMV) retinitis that has become refractory or drug-resistant — where a prior antiviral regimen did not achieve the required virological response and the disease requires escalation to a next-line approach.

Previous Treatment — Escalation Trigger

The preceding line employed cidofovir (CDV), foscarnet (FOS), or combination therapy with ganciclovir plus foscarnet. The trigger for escalation to this protocol is failure to clear CMV antigenemia — the primary virological target of that prior regimen.

Next-Line Approach (Partial Overview)

Management of refractory or drug-resistant CMV retinitis involves antiviral agents with distinct resistance and pharmacological profiles — including options for both oral and intravenous administration — alongside immunological strategies. The full selection criteria, sequencing, and administration details are available in the complete protocol.

Treatment Goals

Clearance of CMV viremia and reduction of intraocular CMV viral load.

Instant Access to Structured Evidence-Based Regimens

References

DOI: 10.3390/v16091427

Letermovir (LET), a CMV-terminase inhibitor preventing viral DNA packaging, is used for drug-resistant CMVR in patients with acute immunodeficiency syndrome.
The recommended dose of LET for CMV retinitis is 480 mg once daily, continued for up to 100 days post-transplant.
It can be administered either orally or through an IV infusion over 1 h.
The recommended dose of MBV is at least 400 mg twice daily, demonstrating similar efficacy to VGCV in clearing CMV viremia among HSCT or SOT.
Despite this limitation, MBV's resistance profile and oral administration make it a valuable option for treating refractory or drug-resistant CMV infections in transplant recipients.
Studies indicate that infusing CMV-specific T cells can restore protective immunity.
Combination therapy with CMVIG and GCV significantly enhance visual outcomes and reduce intraocular CMV viral load in cases of vision-threatening CMVR.

View source ↗