What is the treatment for Cytomegalovirus (CMV)?

Treatment of Cytomegalovirus (CMV) Infection

Valganciclovir and ganciclovir are the first-line agents of choice for the treatment of CMV infections, with specific regimens depending on the clinical scenario and patient population. 1

First-Line Treatment Options

For CMV Retinitis in AIDS Patients:

• Induction therapy:

  • Valganciclovir 900 mg PO twice daily for 21 days 2
  • OR Intravenous ganciclovir 5 mg/kg IV twice daily for 21 days 1, 3

• Maintenance therapy:

  • Valganciclovir 900 mg PO once daily 2

For CMV Disease in Transplant Recipients:

• First-line treatment:
  • Valganciclovir 900 mg PO twice daily for 2-3 weeks (if oral intake is possible) 1, 4
  • OR Intravenous ganciclovir 5 mg/kg IV twice daily for 2-3 weeks 1
  • After 3-5 days, consider switching to oral valganciclovir to complete the 2-3 week course 1

For CMV Esophagitis:

• Intravenous ganciclovir 5 mg/kg IV twice daily for 21-28 days 3
• OR Intravenous foscarnet 60 mg/kg IV every 8 hours or 90 mg/kg IV every 12 hours for 21-28 days 3

Second-Line and Refractory Treatment Options

For Patients Who Cannot Tolerate Ganciclovir or Have Resistant CMV:

• Foscarnet: 60 mg/kg IV every 8 hours or 90 mg/kg IV every 12 hours for 2-3 weeks 1, 3
• Cidofovir: Has shown response rates of 50% for CMV disease and 62% for primary pre-emptive therapy 1
• Maribavir: 400 mg twice daily for refractory or resistant CMV infections 1
  • Superior to other anti-CMV agents in transplant recipients (56% vs 24% clearance rate) 1
  • Associated with less kidney injury than foscarnet (8.5% vs 21.3%) and less neutropenia than valganciclovir/ganciclovir (9.4% vs 33.9%) 1

Monitoring During Treatment

• Complete blood counts and serum electrolytes should be monitored twice weekly during induction therapy and once weekly thereafter 3
• Renal function should be monitored regularly, especially with foscarnet therapy 3
• For CMV retinitis, ophthalmologic examinations should be performed at diagnosis, after completion of induction therapy, 1 month after initiation, and monthly thereafter 3

Important Considerations and Cautions

Adverse Effects:

• Ganciclovir/Valganciclovir: Severe leukopenia, neutropenia, anemia, thrombocytopenia, pancytopenia 2
• Foscarnet: Nephrotoxicity, electrolyte abnormalities (particularly calcium and phosphate), seizures 3
• Cidofovir: Nephrotoxicity, neutropenia, metabolic acidosis 3

Special Populations:

• Patients with hepatic dysfunction: Oral valganciclovir may have reduced efficacy due to decreased conversion to active form 1
• Patients with gastrointestinal GVHD: Intravenous therapy may be preferred over oral valganciclovir 1
• Patients with severe disease or high viral load: Initial intravenous therapy is recommended before transitioning to oral therapy 4

Prevention Strategies:

• For high-risk transplant patients (D+/R-), prophylaxis with valganciclovir 900 mg once daily is recommended:
  • Heart or kidney-pancreas transplant: Start within 10 days post-transplant and continue for 100 days 2
  • Kidney transplant: Start within 10 days post-transplant and continue for 200 days 2
  • Pediatric heart transplant (4 months to 16 years): Dosing based on body surface area and creatinine clearance 2

Treatment Algorithm

1. Assess severity and location of CMV disease
2. For mild to moderate disease with intact GI function:
   • Start valganciclovir 900 mg PO twice daily
3. For severe disease, impaired GI function, or high viral load:
   • Start IV ganciclovir 5 mg/kg twice daily
4. Monitor for response (clinical improvement and viral load decline)
5. If responding after 3-5 days on IV therapy:
   • Consider transition to oral valganciclovir
6. If not responding or developing toxicity:
   • Switch to foscarnet or consider combination therapy
7. For resistant cases:
   • Use maribavir 400 mg twice daily

The key to successful management is early initiation of appropriate antiviral therapy, careful monitoring for toxicity, and consideration of reducing immunosuppression when possible in transplant recipients.