Table 1. Summary of the Existing Drugs for the Treatment of CMV Retinitis.
| Existing Antiviral Agents | Mechanism of Action | Mode of Delivery | Side Effects |
|---|---|---|---|
| Ganciclovir | Inhibits viral DNA synthesis | Intravenous formulation-Cytovene- IV® (Roche) Oral formulation-Cytovene® (Roche) Intraocular implant-Vitrasert® (Bausch & Lomb) |
Hematological abnormalities Poor oral bioavailability (5%) leading to insufficient viral suppression Infection in the contralateral eye and risk of retinal detachment |
| Valganciclovir | Inhibits viral DNA synthesis | Oral formulation-Valcyte® (Roche) | Myelosuppression |
| Foscarnet | Blocks the cleavage of pyrophosphate from the terminal nucleoside triphosphate |
Intravenous formulation-Foscavir® AstraZeneca LP) |
Renal impairment |
| Cidofovir | Inhibits viral DNA synthesis | Intravenous formulation-Vistide® (Gilead Sciences) |
Severe renal toxicity |
| Fomivirsen | Inhibits translation of early CMV proteins | Intravitreal injection-Vitravene® (Isis Pharmaceuticals) |
Adverse ocular side effects such as uveitis |