The implants need to be placed surgically, and the procedure can have complications that impair vision. In addition, intraocular implants do not protect against CMV in the GI tract or the lungs, two common sites of infection. However, the results of a recent study indicate that combining oral ganciclovir therapy with an implant can substantially reduce the risks that the patient will develop CMV disease in the untreated eye or elsewhere in the body. Cidofovir The F.D.A. recently approved another drug for use against cytomegalovirus infections. Cidofovir has the most potent activity against CMV of any of the available agents, and it does not need to be given daily.
Therapy begins with two weekly IV infusions, followed by maintenance doses every other week.
Because these infusions are given so infrequently, it is not necessary to implant a catheter, which is required when infusions are given daily. Unfortunately, cidofovir therapy can cause irreversible kidney damage, which may progress to renal failure. Recent reports indicate that cidofovir can also cause prolonged, painful inflammation of the eye or decreased pressure within the eye, either one of which can lead to loss of vision. In the era before protease inhibitors were widely available, most patients with CMV retinitis experienced disease progression despite antiretroviral treatment. Typically, these patients were re-treated with higher doses of their current drug or were switched from IV ganciclovir to foscarnet, or vice versa.