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Editor’s Note: This is the second in a series of articles we are running on the major manufacturers of HIV medications. The articles do not focus on the companies themselves as much as the life-saving drugs they manufacture. The company featured this time around is Abbott Laboratories, which was founded in 1888 by Chicago physician Wallace Calvin Abbott. Abbott has been a leader in the fight against HIV since the very beginning: they developed the very first HIV blood screening test in the United States, which was approved by the FDA on March 2, 1985 – just four years after the first case of AIDS was reported in the U.S.

There are only two HIV drugs currently marketed by Abbott for the treatment of HIV. But they are both hugely important! They are: Norvir (ritonavir) and Kaletra (lopinavir/ritonavir).

Norvir was approved by the FDA on March 1, 1996. It was the seventh drug approved for treatment of HIV in the United States, and one of the first three in a category known as “protease inhibitors.” Clinical trials of Norvir were done in combination with both one and two of the nucleoside analogue drugs which were already available. Looking back, many scientists credit those early tests of Norvir as the start of the concept of using a “three-drug cocktail” to treat HIV. It was the first approach to treatment of HIV that worked. And it was nothing less than revolutionary! Suddenly even those in the late stages of AIDS had a new lease on life. Three-drug therapy produced results that were so incredible it was called the “Lazarus effect,” after the biblical character who was raised from the dead.

Norvir is rarely used as a primary protease inhibitor in HIV treatment today. Full-dose Norvir requires too many pills (12 a day) and the side-effects are difficult to live with. But scientists have found another use for the drug. Norvir inhibits a liver enzyme that metabolizes protease inhibitors. So prescribing a low dose (usually one or two 100mg capsules – sometimes more) with any of the other protease inhibitors makes them stay in your blood longer. Since they remain active longer, they are more effective. “Boosting” virtually all of the other protease inhibitors with a low dose of Norvir has become standard practice. Sometimes the Norvir “booster” makes it possible to take fewer of the main protease inhibitor, or makes it possible to take it less often, or removes food restrictions. The Norvir almost always makes the main protease inhibitor more effective.

Abbott’s other protease inhibitor, Kaletra, takes advantage of this boosting effect of Norvir. Kaletra, approved by the FDA in October, 2000, is actually a combination of a compound called lopinavir and Norvir (ritonavir).

Kaletra has become the first choice among the protease inhibitors. It is recommended as “preferred” in federal guidelines for those just starting HIV treatment. One reason it is so highly regarded is that it works for such a long time. With many other HIV drugs, the virus mutates over time, and the drug becomes ineffective. But that hasn’t happened with Kaletra.

“We’ve followed patients on Kaletra who were treatment-naïve for more than seven years, and more than 95% who are still in the study have an undetectable viral load,” says George Hanna, MD, Anti-viral Global Project Head for Abbott Laboratories. “There’s no evolution of drug resistance in any of the patients. It’s the longest-running prospective study of any HIV drug, by far.”

On October 28, 2005, Abbott received FDA approval to market a new formulation of Kaletra that replaces the old orange capsules with yellow tablets. Four of the new tablets contain exactly the same amount of medicine as six of the orange capsules, so the dosage has dropped from six-pills-a-day to four. People who are new to HIV treatment can take Kaletra once-a-day. In addition, the new tablets can be taken with or without food, and they do not have to be refrigerated. The old orange capsules were scheduled to have been replaced by the new yellow tablets by March, 2006.

Hats off to Abbott Laboratories for their groundbreaking work in the field of protease inhibitors!

Copyright 2010, Positive Health Publications, Inc.

This magazine is intended to enhance your relationship with your doctor - not replace it! Medical treatments and products should always be discussed with a licensed physician who has experience treating HIV and AIDS!