Ganciclovir intraocular implant

Ganciclovir intraocular implant plus valganddovir 900 mg once daily until immune recovery from ART (Al)° Ganciclovir 5 mg/kg IV every 12 hours or foscarnet 180 mg/kg/day in two or three divided doses IV for 21 to 28 days (Bll)... 

Figure 3-19 Cross-section of ganciclovir implant. (Modified from Charles NC, Steiner GC. Ganciclovir intraocular implant. A cHnicopathologic study. Ophthalmology 1996 103 416-421.)...

Ganciclovir may be administered intravenously, orally, or via intraocular implant. The bioavailability of oral ganciclovir is poor. Cerebrospinal fluid concentrations are approximately 50% of those in serum. The elimination half-life is 4 hours, and the intracellular half-life is prolonged at 16-24 hours. Clearance of the drug is linearly related to creatinine clearance. Ganciclovir is readily cleared by hemodialysis. 

Intraocular implant (Vitrasert) 4.5 mg ganciclovir/implant Idoxuridine (Herplex)... 

Ganciclovir may be administered intravenously, orally, or via intraocular implant. 

In a rare cytomegalovirus comparison trial, a ganciclovir insert (an intraocular implant) plus oral ganciclovir was compared with intravenous cidofovir (18). Based on data from 61 patients (the trial was stopped early owing to low recruitment), cidofovir was associated with a raised serum creatinine concentration of 142 pmol/l (1.6 mg/dl) or greater (0.48 per person-year), 3+ or greater proteinuria (0.29 per person-year), uveitis (0.35 per person-year), and neutropenia (0.11 per person-year). 

Kunou N.-O.Y., Hashizoe, M., Honda, Y., Hyon, S.H. and Ikada, Y. (1995) Controlled intraocular delivery of ganciclovir with use of biodegradable scleral implant in rabbits. Journal of Controlled Release, 37 143-150. 

Martin DF, Parks DJ, Mellow SD, et al. Treatment of cytomegalovirus retinitis with an intraocular sustained-release ganciclovir implant. A randomized controlled clinical trial. Arch Ophthalmol 1994 112 1531-1539. 

Intravitreal ganciclovir injections have been used in some patients, and an intraocular sustained-release ganciclovir implant (vitrasert) is more effective than systemic dosing in suppressing retinitis progression. 

In advanced HIV disease, oral ganciclovir (1000 mg three times daily) may reduce the risk of CMV disease, and possibly mortality, in those not receiving didanosine. The addition of oral high-dose ganciclovir (1500 mg three times daily) to the intraocular ganciclovir implant further delays the time to retinitis progression and reduces the risk of new CMV disease and, possibly, the risk of Kaposi s sarcoma. 

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