a Simple Facts Sheet from the AIDS Treatment Data Network

oral ganciclovir (Cytovene)

CMV is an infection caused by a herpesvirus called cytomegalovirus. When CMV infects the eyes, it's called CMV retinitis. If CMV retinitis isn't treated, it can cause blindness. CMV can also infect other parts of the body, but retinitis is the most common CMV infection in people with AIDS. Although there is no cure for CMV, treatments can delay progression and help prevent blindness.

Ganciclovir (trade name Cytovene), foscarnet (Foscavir) and cidofovir (Vistide) are the approved drugs for treating CMV retinitis. Ganciclovir and foscarnet are usually given by intravenous infusion, which means directly into a vein, twice daily. The infusions are given through a permanent catheter that's placed in your chest in order to have access to a large vein. Cidofovir is also given by infusion, but does not require a catheter because treatments are given once every other week. Once you have CMV disease you need ongoing treatment to prevent the CMV from progressing, and this is called maintenance treatment.

A pill form of ganciclovir was recently approved for maintenance treatment in some cases. You have to take 12 capsules a day. If you add 12 capsules to all the other drugs you may have to take, it's a lot. But while the 12 capsules may seem like a lot, the capsules are easier to take than IV ganciclovir.

Although IV infusion is still necessary for the first part of treatment, called induction therapy, oral ganciclovir can be used for maintenance. Oral ganciclovir is taken with food, either three times a day or six times a day.

Clinical trials comparing the capsule and IV forms of ganciclovir for maintenance treatment showed that progression of CMV retinitis in those taking the oral form was somewhat faster than those on IV infusion. The major side effects of the capsules, as with IV ganciclovir, are blood disorders called granulocytopenia, anemia and thrombocytopenia. The most common side effects experienced by those taking the capsules compared to IV infusion were diarrhea, fever, leukopenia, and nausea.

The pill form of ganciclovir has now been approved for the prevention of CMV disease in people at risk. People at risk for CMV are usually those with low T cells (usually under 50) who have been exposed to CMV in the past. The doctor can do a test to see if you have been exposed to CMV.

Oral ganciclovir was approved for CMV prevention because the results of one study showed that prophylaxis can delay the onset of CMV disease in people with low T4 cell counts. Prophylaxis is when a drug is taken to prevent active disease. Taking the capsules for prevention in this study seemed to reduce active CMV disease by about half. Because of the side effects, those taking the ganciclovir capsules had to take G-CSF and erythropoietin, which stimulate growth of new blood cells, more often than study participants who got placebo.

Another CMV prevention study was very recently completed by the government-sponsored Community Programs for Clinical Research on AIDS (CPCRA). This results of this study did not support the use of oral ganciclovir for prevention of CMV disease. This study has been criticized for not giving participants regular check ups with an opthamologist (eye doctor). Further studies of oral ganciclovir for CMV prevention are planned to try and work out who can benefit from preventive therapy the most.

Other studies for treatment of CMV are ongoing. A study of oral versus IV ganciclovir for the treatment of CMV colitis is enrolling. CMV colitis is CMV infection in the upper or lower gastrointestinal tract.

A study comparing different treatments for CMV retinitis is also enrolling. Participants will be treated with IV ganciclovir, an eye implant with oral ganciclovir, or an eye implant alone. To participate, you must only have CMV retinitis in one eye. Call The Network for more information.

The decision whether to take oral ganciclovir for prevention of CMV is a difficult one. You should discuss your risk for CMV with your doctor. There is a possiblity that if you develop CMV while taking oral ganciclovir the CMV will be harder to treat because of resistance. The company that makes the drug says that after 10 months of treatment only 1 percent of people became resistant to ganciclovir. It is known that one person on the CMV prevention study developed CMV disease that could not be treated with ganciclovir, foscarnet or cidofovir.

The Simple Facts Project is a program of The Network. If you need help finding out whether or not a specific drug or therapy is covered by private or public insurance, contact The Network at (800) 734-7104. This information does not intend to promote or endorse any specific treatment for any health related condition.