Once a Day: A New Line of HIV Drugs That Is Easier to Take

Until recently, doctors assumed an increase in HIV viral load meant that a patient's drugs were not working any more. It was assumed the virus had grown resistant to the drugs. Doctors quickly looked for new drug regimens because higher viral loads meant T-cells were being killed and the disease was progressing.

Today there are resistance tests. Now doctors can check to see how resistant the virus has become when a drug fails. Often the resistance tests showed the virus was not resistant to the drugs at all. So in theory, the drugs should be working.

The easiest way to explain this unexpected result is that people were missing doses. Skipping doses will lead to viral loads high enough to make doctors assume the drugs have failed.

People tend to skip doses for two basic reasons:

1. The medicines have bad side effects. One person put it this way: the first time he felt good in three years was also the first time he forgot to take his drugs.

2. The medicines have too complicated a dosing schedule. Many of the early treatment regimens required people to take one pill with no food for hours, another only with food, three times a day. This would lead to trying to remember as many as six times a day as many as a dozen pills.

But the world has changed.

Today, there are drugs with fewer side effects and drugs that only need to be taken once a day. Some are available now, and others will be available soon.

Sustiva (efaveranz), Videx (ddI), Viread (PMPA) are all once-a-day drugs. And soon, Zerit (d4t) and Epivir (3TC) are expected to be approved for once a day dosing.

FTC, presently in phase III testing, is a once-a-day drug. Under study for once-daily dosing are also abacavir, nevirapine, and most of the protease inhibitors when taken with a certain dose of ritonavir (Norvir).

Finally, in clinical trials there are several once-a-day drugs, including a protease inhibitor now called atazanavir (brand named Zrivada once known as BMS 232632).

Over the years, the 'three times a day with food restrictions' schedule for HIV drugs gave way to twice-a-day regimens -- a big improvement! Today there are once-a-day regimens that will help even more with compliance.

If you are starting therapy, one consideration needs to be how consistent you are likely to be given the particular dosing schedule. And if your drug regimen is failing, take a resistance test. Maybe you are missing doses and the dosing schedule is the problem, not resistance to the drugs.

David Scondras is the founder and chairman of Search For A Cure. Scondras developed the nationally recognized HIV treatment series, Reasons for Hope. All articles in the series are reviewed by expert HIV doctors and scientists and an HIV positive and negative focus group to ensure both accuracy and understandability.

This article was reviewed by Dr. Cal Cohen, Medical Director of Community Research Initiative of New England.