Top U.S. Scientist to Use New AIDS Drugs Seeking Cure
By John Lauerman (bloomberg.com, 15-5-2007)
AIDS may be cured in a select group of patients who now have extremely low levels of virus in their bodies by aggressively dosing them for a year with new HIV drugs from Roche Holding AG and Merck & Co., according to the top U.S. infectious disease scientist.
Research released yesterday suggested that 7.7 years of combination therapy might cut HIV to very low levels in those treated early and faithfully. The next step is to see if aggressive treatment with new drugs for a year will cure the disease, said Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases.
Patients are already being lined up for the new study. If doctors get the virus to levels where it seems to disappear, they'll stop treatment, Fauci said in a telephone interview yesterday. Patients will then be monitored so therapy can quickly resume if the virus reappears, he said.
"The first step is to see how far we can push the envelope,'' said Fauci, who co-authored the study published yesterday in the Journal of Infectious Disease. "We now have a scientific basis to feel that it's at least worth pursuing it in some select patients.''
The shares of Merck, based in New York, rose 42 cents to $52.50 at 10:49 a.m. in New York Stock Exchange composite trading, while Roche's shares rose $2.10 to $228.90.
HIV, the human immunodeficiency virus which causes AIDS, infects about 40 million people worldwide, and 1 million in the U.S. The virus mutates constantly to elude the body's defenses as well as drugs, such as Bristol-Myers Squibb Co.'s Sustiva. It can also hide in immune cells, called resting T-cells, where it is relatively safe from treatments.
Early Treatment
Early treatment can keep the virus from reaching high numbers within those T-cells, Fauci said. He and NIAID researcher Tae-Wook Chun followed seven HIV patients for three- and-a-half to four-and-a-half years, measuring the number of resting T-cells in which HIV remained as time went on.
They found that early treatment with drugs from three classes, each of which hits the virus at a different point of vulnerability, brings down viral levels quickly. With this treatment, the number of infected resting T-cells can be halved every 4.6 months, the study said. The study will be published in the June 15 issue of the Journal of Infectious Diseases.
Based on that finding, they and colleagues at the University of Washington in Seattle estimated that 7.7 years of three-drug therapy would all but eliminate HIV in patients who began treatment early.
Small Group
While the number of patients who got the three-drug regimen early, kept it up for years, and have low levels of virus may be small, studying them "will be of considerable value in assessing the feasibility of eradication of HIV,'' Fauci and his coauthors said in the journal article.
Treatment in the next group of patients will probably include Roche's Fuzeon, which prevents the virus from attaching to immune cells, and Merck's Isentress, which stops HIV from adding its genes to the cell's genome. Isentress is in the final stages of development.
Each drug attacks a part of the virus untouched by other classes of medications. Such drugs might give the best chance to eradicate HIV because the virus is unlikely to have mutated to develop defenses against the new medications, Fauci said.
The proposed study might also help doctors decide when and how to use currently available HIV drugs, some of which have been associated with complications such as heart disease after long-term use, Fauci said.
Stronger Treatment
If doctors have a chance of getting patients completely off drugs, it may be worth the risk of stronger treatment, he said.
Another risk is that measurement of low HIV levels isn't always accurate. If the virus actually takes longer than eight years to eliminate, or can't be driven out, patients who think they are cured may be taking a chance by halting HIV drugs, said David Margolis and Nancie Archin of the University of North Carolina in Chapel Hill, in an editorial in the same journal.
"The few infected cells remaining might be enough to reignite infection,'' they said. "And, of course, the possibility exists that HIV may rarely persist in cells other than resting T-cells.''
Patients will be closely monitored to make sure that treatment resumes quickly if viral levels begin rising again, Fauci said. The U.S. government recommended expanded testing for HIV last year to try to diminish spread by making infected people aware of their status. The strategy might also get more people into treatment early, offering the possibility that they could be cured, if aggressive, early treatment works.
By John Lauerman (bloomberg.com, 15-5-2007)
AIDS may be cured in a select group of patients who now have extremely low levels of virus in their bodies by aggressively dosing them for a year with new HIV drugs from Roche Holding AG and Merck & Co., according to the top U.S. infectious disease scientist.
Research released yesterday suggested that 7.7 years of combination therapy might cut HIV to very low levels in those treated early and faithfully. The next step is to see if aggressive treatment with new drugs for a year will cure the disease, said Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases.
Patients are already being lined up for the new study. If doctors get the virus to levels where it seems to disappear, they'll stop treatment, Fauci said in a telephone interview yesterday. Patients will then be monitored so therapy can quickly resume if the virus reappears, he said.
"The first step is to see how far we can push the envelope,'' said Fauci, who co-authored the study published yesterday in the Journal of Infectious Disease. "We now have a scientific basis to feel that it's at least worth pursuing it in some select patients.''
The shares of Merck, based in New York, rose 42 cents to $52.50 at 10:49 a.m. in New York Stock Exchange composite trading, while Roche's shares rose $2.10 to $228.90.
HIV, the human immunodeficiency virus which causes AIDS, infects about 40 million people worldwide, and 1 million in the U.S. The virus mutates constantly to elude the body's defenses as well as drugs, such as Bristol-Myers Squibb Co.'s Sustiva. It can also hide in immune cells, called resting T-cells, where it is relatively safe from treatments.
Early Treatment
Early treatment can keep the virus from reaching high numbers within those T-cells, Fauci said. He and NIAID researcher Tae-Wook Chun followed seven HIV patients for three- and-a-half to four-and-a-half years, measuring the number of resting T-cells in which HIV remained as time went on.
They found that early treatment with drugs from three classes, each of which hits the virus at a different point of vulnerability, brings down viral levels quickly. With this treatment, the number of infected resting T-cells can be halved every 4.6 months, the study said. The study will be published in the June 15 issue of the Journal of Infectious Diseases.
Based on that finding, they and colleagues at the University of Washington in Seattle estimated that 7.7 years of three-drug therapy would all but eliminate HIV in patients who began treatment early.
Small Group
While the number of patients who got the three-drug regimen early, kept it up for years, and have low levels of virus may be small, studying them "will be of considerable value in assessing the feasibility of eradication of HIV,'' Fauci and his coauthors said in the journal article.
Treatment in the next group of patients will probably include Roche's Fuzeon, which prevents the virus from attaching to immune cells, and Merck's Isentress, which stops HIV from adding its genes to the cell's genome. Isentress is in the final stages of development.
Each drug attacks a part of the virus untouched by other classes of medications. Such drugs might give the best chance to eradicate HIV because the virus is unlikely to have mutated to develop defenses against the new medications, Fauci said.
The proposed study might also help doctors decide when and how to use currently available HIV drugs, some of which have been associated with complications such as heart disease after long-term use, Fauci said.
Stronger Treatment
If doctors have a chance of getting patients completely off drugs, it may be worth the risk of stronger treatment, he said.
Another risk is that measurement of low HIV levels isn't always accurate. If the virus actually takes longer than eight years to eliminate, or can't be driven out, patients who think they are cured may be taking a chance by halting HIV drugs, said David Margolis and Nancie Archin of the University of North Carolina in Chapel Hill, in an editorial in the same journal.
"The few infected cells remaining might be enough to reignite infection,'' they said. "And, of course, the possibility exists that HIV may rarely persist in cells other than resting T-cells.''
Patients will be closely monitored to make sure that treatment resumes quickly if viral levels begin rising again, Fauci said. The U.S. government recommended expanded testing for HIV last year to try to diminish spread by making infected people aware of their status. The strategy might also get more people into treatment early, offering the possibility that they could be cured, if aggressive, early treatment works.
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