A single pill once a day to treat HIV is the goal set by two drug companies that have agreed to collaborate. It may be on the market within two years.
Bristol-Myers Squibb produces Sustiva, recommended in most treatment guidelines as part of a preferred initial therapy. It is in the class of drugs known as non-nucleoside reverse transcriptase inhibitors ( NNRTIs ) .
Gilead Sciences produces Viread and Emtriva, two popular and potent second-generation drugs in the reverse transcriptase inhibitor ( NRTI ) class. They also may be used as part of an initial regimen.
The combination of these three drugs has been used in thousands of patients with good results. However, a new round of trials will be required to demonstrate that packing them all into the same pill results in the same therapeutic effect with no additional side effects.
It is the first time that two companies have agreed to collaborate to produce a single anti-HIV pill that contains multiple drugs. Success is not assured.
Several years ago Merck created Trizavir, a combination of AZT, 3tc, and abacavir, three drugs in the NRTI class. It hoped that the single pill might become a standard treatment. But a clinical trial was stopped early in 2003 when it became apparent Trizavir was not as effective in controlling HIV as combining drugs from two classes. Trizavir is recommended for use only in combination with another class of antiretroviral drug.
Kaletra is another possible single drug therapy. It combines the protease inhibitor lopinavir with a sub-therapeutic dose of the protease inhibitor ritonavir to keep it in the bloodstream longer.
A pilot trial at a Houston clinic has demonstrated promising results and the manufacturer, Abbott Laboratories, is backing full-scale clinical trials of this use. Kaletra currently it is approved for use only in combination with other drugs.
Some industry analysts see the Bristol-Myers/Gilead alliance in developing their combination single pill as a defensive move to protect their market share against the ease of use of Kaletra, should it be approved for single drug use.