Simple Facts Sheets: adefovir (Preveon)

	a Simple Facts Sheet from the AIDS Treatment Data Network
	adefovir (Preveon)
	For more information about clinical trials for anti-HIV treatments currently enrolling, see the clinical trials page Drugs for treating HIV.

Adefovir dipivoxil (Preveon) is the first available drug in a new class of anti-HIV drugs called nucleotide analogs. Nucleotide analogs work against HIV's reverse transcriptase enzyme as do the nucleoside analog drugs AZT, ddI, ddC, d4T and 3TC. The difference is that the nucleoside analogs have to go through complicated chemical processing inside cells in the body in order to work against HIV. Adefovir goes through a simpler chemical process.

Trial results: Studies show that adefovir can add some extra anti-HIV effect to combination treatment. One trial enrolled 442 people with viral loads over 2,500 copies who were already taking combination anti-HIV drugs. About half the participants added adefovir to their treatment, and the other half added a placebo or dummy pill. The group that added adefovir had an average decrease in viral load of just over 40% after six months. The group that didn't get adefovir showed no change in viral loads. Another study found that adefovir could reduce hepatitis B viral levels by more than 99%.

Side effects: The main side effects are nausea, diarrhea and liver problems. Kidney problems have also been seen. Two doses of adefovir have been tried: 60 mg and 120 mg, taken once a day. About 40% (more than a third) of the people in studies who took the higher dose for more than six months developed signs of serious kidney damage called Fanconi-like syndrome. If you take adefovir, you must have your kidney function checked every month.

Kidney function is checked by laboratory tests that measure serum creatinine and protein in the urine. If levels are high, you may have to stop the drug or reduce the dose. The expanded access program is providing adefovir at either 60 mg or 120 mg a day. The lower dose may have less risk for kidney damage and about the same anti-HIV effect; this is still being studied.

Taking the drug: Adefovir comes as one pill, taken once a day. Because adefovir reduces the amount of L-carnitine, a natural substance in the body needed for getting energy into muscles, you must take a daily L-carnitine supplement with adefovir.

Expanded access: To enroll in the Preveon expanded access program, you must have been taking a combination of at least two nucleoside analog anti-HIV drugs and one protease inhibitor, and the treatment is no longer working. For more information call Gilead Sciences at (800) GILEAD-5 (445-3235).

Two other experimental anti-HIV drugs are also available through expanded access programs: abacavir (Ziagen, formerly known as 1592U89), and efavirenz (Sustiva, formerly known as DMP266). The Network has separate Simple Fact Sheets on these drugs. Call (800) 734-7104 for free copies. To contact the expanded access programs directly, for abacavir call (800) 501-4672, and for efavirenz call (800) 998-6854.

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.

Simple Facts index Network home page