News (Updated February 8,
2003)
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Tue Feb 4, 2:50 PM ET
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By Merritt McKinney
NEW YORK (Reuters Health) - Powerful drugs used to fight HIV, the virus that causes AIDS, are known to increase triglycerides and cholesterol in the blood, both of which can promote the development of artery disease.
Now, new research in mice suggests that the drugs, known as protease inhibitors, may directly contribute to artery disease even before triglyceride and cholesterol levels rise.
Since the research was carried out in animals, it is too soon to say whether protease inhibitors have the same effect in people, Dr. Eric J. Smart, the study's lead author, told Reuters Health in an interview.
"We now are checking to see if the same thing happens in patients," said Smart, who is at the University of Kentucky Medical School in Lexington.
"This doesn't mean that the protease inhibitors should be stopped," Smart said. He noted that the drugs, which are mostly used in combination with other anti-HIV drugs, can suppress HIV and extend life in many people.
But if protease inhibitors turn out to have the same effect on the arteries in humans as they do in mice, Smart said, "we may have to be a little more careful" in how the drugs are used.
Current screening for triglycerides and cholesterol do not detect the kind of artery problems found in the mouse study, according to the Kentucky researcher. There are several research screens, however, that might be developed into a clinically useful test, he said. Of course, Smart noted that whether such a screen will be needed depends on whether the mouse results are confirmed in humans.
In the study, Smart's team found that three different protease inhibitors--ritonavir, indinavir and amprenavir--increased levels of a protein called CD36 and enzymes called cholesteryl esters in cells called macrophages. These changes, which are typical of what happens in the lesions that build up to clog arteries, occurred both in mice and in samples of human cells.
And when the researchers tested low doses of the protease inhibitors in mice, the animals developed early artery disease. This was true even though their triglycerides and cholesterol levels remained normal.
The study provides the first evidence that protease inhibitors have a direct effect on the development of artery disease, according to Dr. David Y. Hui of the University of Cincinnati College of Medicine in Ohio.
It is possible that protease inhibitors increase the risk of artery disease not only by boosting levels of triglycerides and cholesterol but also by acting directly on macrophages, Hui notes in an editorial that accompanies the study.
Both of these actions share a common pathway, so if future evidence confirms the findings, it may be possible to develop drugs that would prevent the artery complications of protease inhibitors, Hui suggests.
The study was funded by the National Institutes of Health and drugmaker Bristol-Myers Squibb.
SOURCE: Journal of Clinical Investigation 2003;111:317-318,389-397.
In a paper (CD4+ T Cells Are Required for Secondary Expansion and Memory in CD8+ T Lymphocytes, Nature, February 2003) published today in the scientific journal Nature, Stephen P. Schoenberger, Ph.D., and a team of LIAI researchers shed light on just how the immune system responds to disease-causing pathogens such as viruses and bacteria.
The LIAI team found that certain T cells (CD8 killer cells) in the body can make an immediate response to invading pathogens, but it takes a second type of T cell, called a CD4 helper T cell, to create memory cells. Memory cells recognize and respond to repeated infections by the same pathogen and are essential in producing the long-term immunity sought from a vaccine.
Also CD4 helper T cells are the cells that are targeted and eventually eliminated by HIV, the virus that causes AIDS. This may help to explain why the CD8 T cells do not effectively protect people infected with HIV.
"Once we know how these helper cells work to stimulate the killers, researchers can use that knowledge to create more effective and safer vaccines," said Schoenberger. "At some point, they may be able to use this knowledge to create very specific immunizations for diseases such as cancer."
Schoenberger and his team were able to make their observations in vivo (within a living organism) using CD4-intact and CD4-deficient mice. Mice with intact CD4 cells were able to respond to a repeat exposure to a vaccination by producing a five-fold increase in the number of CD8 killer cells. Those lacking helper T cells were unable to make the same response.
"Our results provide new insight into the nature of T-cell help by demonstrating the helper cells are absolutely required for a repeat response to an antigen, but not for the initial response," Schoenberger said.
La Jolla Institute for Allergy and Immunology is a non-profit, public benefit corporation conducting basic medical research on various diseases of the immune system, including diabetes, arthritis, multiple sclerosis, cancer, allergy and infectious diseases. The institute's research staff includes approximately 100 Ph.Ds.
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Tue Feb 4, 8:53 PM ET
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Randy Dotinga, Gay.com / PlanetOut.com Network
SUMMARY: Doctors in Pennsylvania have reported what may be a first: a likely case of HIV transmission between female sex partners.
Doctors in Pennsylvania have reported what may be a first: a likely case of HIV transmission between female sex partners.
An HIV-positive bisexual woman may have infected her partner by using sex toys so vigorously that she bled during intercourse, according to a report in the Feb. 1 issue of the medical journal Clinical Infectious Diseases.
The partner who became infected, a 20-year-old college student, said she had only engaged in lesbian sex over the past two years and always with the same woman. Genetic tests on the viruses within the women suggest that the bisexual woman infected the other.
The bisexual woman knew she was HIV-positive and took precautions when she had sex with men, as directed by her doctor, the report said. She also took care to not share toothbrushes and razors, according to the report by Dr. Helena Kwakwa of Philadelphia's Mercy Hospital and Dr. M.W. Ghobrial of Mercy Fitzgerald Hospital in Darby, Pa.
Doctors reported a few cases of apparent lesbian-to-lesbian HIV transmission in the late 1980s and early 1990s, said Dr. Jeanne Marrazzo, an expert in lesbian sexually transmitted diseases at the University of Washington. But the doctors had to rely on the women's reports about their sex lives.
"None suggest that transmission occurred as strongly as this case does," Marrazzo said. "It would be unlikely for the HIV virus to be so similar in both of these women if one hadn't given it to the other."
Transmission may have come through vaginal fluids infected with blood, she said, and the case confirms that lesbians should be aware of HIV risks, she said. "It's a good idea to know your partner in more ways than one. Does she have HIV? Ever been tested? Had sex with someone who had it, or was high risk for it? Used IV drugs or crack?"
Lesbians are vulnerable to a variety of STDs besides HIV, but many are unaware of the risks, Marrazzo said.
"We just finished several focus groups here (in Seattle) because we're starting a study on a safer sex intervention among lesbians. The lack of knowledge about basic STDs and how a woman might get them from another woman was really disturbing. There's a ton of education needed -- not just of lesbians, but of their health care providers," she said.
Women who have sex with women should get tested for diseases like chlamydia, herpes and HIV before beginning a sexual relationship, she said. "If that's not possible, know how to use barrier protection (gloves, condoms on sex toys) if indicated. It really depends on whether two women are planning to be monogamous, and what STDs they might be bringing into the relationship to start with."
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Tue Feb 4, 8:53 PM ET
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Christopher Lisotta, Gay.com / PlanetOut.com Network
SUMMARY: Doctors in San Francisco report that they are seeing an increase in cases of a drug-resistant bacterial skin infection among gay men.
Doctors in San Francisco report that they are seeing an increase in cases of a drug-resistant bacterial skin infection among gay men, just a week after similar reports started coming out of Los Angeles.
The bacteria, Staphylococcus aureus (better known as staph), has been a common problem in nursing homes and hospitals. But in the past several months, in both Los Angeles and San Francisco, there have been outbreaks among gay and HIV-positive men and groups of prisoners.
Although HIV-positive men are thought to be more susceptible to infections because they often have suppressed immune systems, doctors are not sure why apparently healthy people with no broken skin have been getting infected. Reports of the outbreaks have been spreading through gay communities in both cities, but doctors are quick to point out the infections can still be controlled.
"I don't want people to think this is the equivalent of a new HIV/AIDS disease," said San Francisco Department of Public Health Director Dr. Mitch Katz to the San Francisco Chronicle. As of yet there have been no reported cases of anyone dying from the infection, but the drugs needed to fight the resistant staph often have to be given intravenously and can require hospitalization.
The infections are usually spread by skin-to-skin contact or by touching a recently contaminated surface, according to the Chronicle.
No one is quite sure how many cases of the drug-resistant infection are out there, although one San Francisco doctor familiar with the outbreak estimated the city's cases number between 200 and 300.
Until recently, state and federal health officials were not asking doctors to report on individual cases. The Centers for Disease Control and Prevention (CDC) is now testing the strains that have appeared in San Francisco and Los Angeles to see if they are the same.
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Thu Feb 6, 2:32 AM ET
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By LISA LEFF, Associated Press Writer
SAN FRANCISCO - Government researchers from California and Mexico plan to jointly study the spread of AIDS among migrant workers and their families in hopes of preventing it from reaching epidemic proportions in Mexico.
The study will be the most comprehensive effort to track HIV infection rates in the migrant work population, said Dr. George Lemp, director of the University of California's AIDS Research Program.
The program was announced Wednesday as representatives from Mexico and California's health and social service agencies met in San Francisco to discuss details of the initiative. Its focus will be seasonal farm workers, day laborers and urban service workers in Fresno and San Diego counties in California; those same groups and their relatives will also be studied in the Mexican states of Oaxaca and Michoacan.
"Addressing the health needs of Mexican migrants is very important both to Mexico and California, and previously there hadn't been a collaborative effort to address the matter jointly," Lemp said.
For three years, scientists will conduct field interviews, collect blood and urine samples and develop statistical models before making specific policy and program recommendations.
Mexico's HIV-infection rate of 0.3 percent is five to six times lower than the United States, said Dr. Carlos Magis Rodriguez, research director for Mexico's National Center for the Prevention and Control of HIV/AIDS. While the rate has held steady in Mexico since the late 1980s, he said the threat of Mexicans contracting the virus when they head north for jobs cannot be ignored.
"That means we are in a position where people that are from Mexico who go to the states have more probability of getting infected with HIV than they would if they stayed in Mexico and engaged in the same behaviors," Magis said, adding that migrant workers may be more likely to participate in high risk activities "because a migrant loses all the social support system — friends, relatives and language."
Smaller studies conducted in the United States have attempted to pinpoint HIV-infection rates among migrant farm workers, with varied results. One such study found that 13 percent of 198 migrant farmers in South Carolina were HIV-positive; another in North Carolina revealed that 3 percent of patients at a rural health clinic who worked as seasonal laborers were infected.
The study will also track infection rates for other sexually transmitted diseases and tuberculosis.
| Press Release | Source: Boehringer Ingelheim |
Thursday February 6, 7:00 am ET
Clinical Trial Program Is Largest Ever for HIV-Positive
Patients Previously Treated With Three Classes of Antiretrovirals
Resistance to currently available anti-HIV drugs is an increasingly prevalent concern for highly treatment-experienced HIV-positive patients worldwide, creating an urgent need for new treatments that are effective against multi-drug resistant virus. Up to 14% of recently infected patients have been reported to be infected with a strain of virus that has drug resistance mutations or that has reduced susceptibility (effectiveness) to a particular drug.(1), (2), (3) Available clinical and in vitro data suggest that tipranavir may be active against strains of HIV-1 that are resistant to currently available peptidic protease inhibitors (PIs), offering hope for patients with multi-drug resistant virus. Phase III trials are designed to confirm these initial studies.
"This is an important milestone in the development of tipranavir," said Dr. Andreas Barner, Member of the Board of Managing Directors of Boehringer Ingelheim. "We have designed a clinically relevant Phase III trial program that includes resistance testing for all patients, allows the use of other expanded access HIV/AIDS therapies, and provides access to a significant number of triple class-experienced patients worldwide. It's the largest trial program ever conducted in this patient population, recruiting over 1500 patients in total."
The Phase III RESIST (Randomized Evaluation of Strategic Intervention in Multi-Drug ReSistant Patients with Tipranavir) clinical trial program has been designed to study the safety and efficacy of tipranavir (boosted with low-dose ritonavir) versus a low-dose ritonavir-boosted comparator protease inhibitor (PI) that is chosen by the patient's physician on the basis of treatment history and baseline resistance testing. Study participants will all be highly treatment-experienced HIV-positive adults. Phase III of clinical development is the final stage of testing before a drug is submitted to worldwide regulatory authorities for review and consideration for marketing approval. The RESIST Program consists of two Phase III pivotal trials (RESIST 1 and RESIST 2) and two companion trials (study 1182.51 and RESIST 3) available for even more advanced patients.
"The impressive activity seen in initial studies demonstrate that tipranavir may be a promising option for patients with existing PI-resistant virus. I look forward to seeing the outcome of these important Phase III trials," said Kathleen Squires, MD, Associate Professor of Medicine at the Keck School of Medicine of the University of Southern California, and an investigator in the RESIST program.
In initial clinical studies, the most common adverse events associated with tipranavir were diarrhea, nausea, fatigue, headache and vomiting. In addition, the elevation of transaminases has been observed in patients treated with tipranavir.
RESIST Clinical Trial Program Design
RESIST 1 will enroll more than 500 patients at more than 115 trial sites in the United States, Canada and Australia. All participants will receive resistance testing at baseline to determine the optimal drugs to combine with tipranavir, as each patient will receive an individualized background treatment regimen. The choice of comparator PI and background regimen is up to the investigator. A similar clinical trial, RESIST 2, will enroll more than 800 patients in Europe and South America.
Companion studies for patients with extremely limited treatment options will also be available at participating RESIST study sites for patients who do not qualify for the RESIST trials. Boehringer Ingelheim will also study tipranavir in treatment-naïve adult patients and conduct trials in children. The dose for tipranavir that will be studied in the Phase III clinical program is 500 mg of tipranavir taken with 200 mg of ritonavir (to boost tipranavir drug levels in the body) twice daily.
Tipranavir
Tipranavir has a non-peptidic chemical structure, which is believed to allow it to bind more flexibly to the active site of the HIV protease. This flexibility may explain why the resistance profile of tipranavir is different from available peptidic PIs. While the exact resistance profile of tipranavir is still being defined, initial clinical and in vitro data suggest that tipranavir may be active against strains of HIV-1 that are resistant to currently available peptidic protease inhibitors. Preliminary results from Phase II clinical studies, which require confirmation by the RESIST trial program, suggest that reduction in the susceptibility of HIV-1 to tipranavir is uncommon and is associated with at least 16 protease inhibitor mutations at baseline.
HIV Drug Resistance
The HIV-1 virus acquires HIV drug resistance after sub-optimal exposure to antiretroviral therapy, which becomes more of an issue the longer patients are receiving treatment. Drug resistance may render drugs less effective, or even ineffective, thus significantly limiting treatment options for people with HIV/AIDS. Resistance generally occurs as a result of changes -- or mutations -- in HIV's genetic code.
Boehringer Ingelheim
Boehringer Ingelheim is committed to the research and development of novel antiretroviral agents. VIRAMUNE (nevirapine) is a product of original research done at Boehringer Ingelheim. VIRAMUNE was the first member of the non-nucleoside reverse transcriptase inhibitor (NNRTI) class of anti-HIV drugs. Boehringer Ingelheim is committed to the rapid development of the investigational non-peptidic protease inhibitor tipranavir. The company is involved in basic research and is committed to improving HIV therapy by providing physicians and patients with innovative antiretrovirals.
| Press Release | Source: Roche Molecular Systems, Inc. |
Thursday February 6, 8:05 am ET
HIV viral load measurement is an essential parameter used in HIV treatment decisions. The COBAS AmpliPrep/COBAS AMPLICOR HIV-1 MONITOR Test, v1.5 was designed to address the increasing needs of clinical laboratories to enhance productivity and reduce operational costs.
The COBAS AmpliPrep(TM) instrument automates the purification of HIV-1 RNA, together with the COBAS AMPLICOR(TM) instrument, which uses PCR technology to amplify and identify genetic material. This allows for accurate detection of even small amounts of viral RNA in the blood.
The test is seen as an important breakthrough in making advanced molecular diagnostic resources more affordable to operate in laboratories.
"Classical non-automated PCR methods are labor intensive. The use of the AmpliPrep and COBAS AMPLICOR instruments to automate the classic PCR process has been shown to reduce the hands-on-time of specimen preparation, amplification and detection by 60 - 80 percent," said Prof. Donald Jungkind, PhD, Director of the Clinical Microbiology Laboratory at Thomas Jefferson University Hospital in Philadelphia, Pennsylvania, and principal investigator in early evaluations of this new assay. "Time saved by using this new system was significant and will increase overall laboratory productivity and result integrity while lowering labor costs."
Studies submitted to the FDA for review indicate that the COBAS AmpliPrep/COBAS AMPLICOR HIV-1 MONITOR Test, v 1.5, like the FDA-approved AMPLICOR HIV-1 MONITOR® Test, version 1.5 offered by Roche, provides consistent detection of viral load levels as low as 50 copies of HIV-1 RNA per milliliter (c/mL) of plasma. This level of sensitivity is critical for optimizing treatment strategies. Maintaining an infected patient's viral load below 50 c/mL (undetectable) has been associated with a more complete and durable viral suppression.
Of equal importance, this test has the continued ability to quantitate HIV-1 Group M subtypes A-G. While HIV-1 subtype B continues to predominate in Western Countries, studies now confirm that the incidence of HIV-1 non-B subtypes is increasing all over the world. A test's ability to detect a broader range of these genetically diverse viruses will, therefore, be crucial to HIV patient care on a global basis.
"Our FDA approved viral load assays have been used for the submission of most of the new HIV drugs approved by the FDA since 1996," said Dr. Heiner Dreismann, President and CEO of Roche Molecular Systems, Inc. "We are proud to bring HIV viral load testing to the next level by offering a more automated solution which will allow laboratories to address increasing demand for such testing."
Roche is a worldwide leader in developing PCR-based diagnostic tests. The company first developed a PCR assay for HIV-1 in 1996. This fully automated assay marks Roche's fifth HIV-1 PCR product submission to the FDA.
According to the World Health Organization, more than 42 million people worldwide were living with HIV at the end of 2002, an infection rate that is expected to increase. The demand for antiretroviral therapy and consequently, viral load testing, is expected to rise accordingly. Roche Molecular Systems, Inc. provides both manual and automated HIV-1 RNA reagent kits and testing systems to laboratories throughout the world.
| Press Release | Source: MedMira Inc. |
Thursday February 6, 8:10 am ET
"The delivery of this shipment to our Tunisia distributor is a significant milestone for our Sales and Marketing team", said Stephen Sham, Chairman and CEO of MedMira. "We have spent considerable time over the past years building relationships in anticipation of entering the rapid diagnostic product market in the African nations. This contract, while small, has opened the door to the private sector market, positioning MedMira to capture significant market share in the African diagnostic marketplace."
MedMira is a commercial biotechnology company that develops, manufactures and markets qualitative, in vitro diagnostic tests for the detection of antibodies to certain diseases, such as HIV, in human serum, plasma or whole blood. The most advanced of these products are the Reveal and MiraWell(TM) Rapid HIV tests, believed to be in the final stages of the United States FDA and Chinese SDA regulatory approval process. Other existing products include tests for Hepatitis B, Hepatitis C and combination tests for Hepatitis C/Hepatitis B/HIV. All of MedMira's diagnostic tests are based on the same flow-through technology platform thus facilitating the development of future products. MedMira's technology provides a quick (under 3 minutes), accurate, portable, safe and cost-effective alternative to conventional laboratory testing.
| Press Release | Source: Durex(R) Consumer Products |
Thursday February 6, 9:05 am ET
Durex GenSex Survey Reveals 80% of Young Adults Fib About Matters of the Heart
America's "sex generation" of young adults may have sex earlier, but are they more honest about their sexuality than previous generations? Nope. According to the GenSex Survey, lying tops the list of young adult relationship habits. About 80% of those 18-24 would lie to their sexual partners about ... well ... almost everything.
Fidelity is the number one fib young adults are telling. Only 15% of adults 18-20 and 11% of adults 21-24 would reveal having been unfaithful. On average more women (12%) than men (11%) were likely to tell their partners they'd done the deed with someone else.
Says Sari Locker, renowned educator and author, "The GenSex Survey reveals that while adults have sex earlier, many are still lacking the skills for engaging in those difficult discussions about sex, but honest communication in this regard is vital. For successful relationships, young adults should incorporate open dialogue as a basic, and often stimulating, component of their sexual experiences."
Also Topping the Most Lied About List
5. Age
4. Number of Sexual Partners
3. Sexual Fantasies
2. Sexually Transmitted Diseases (STDs)
1. Fidelity
"As the world's leading condom brand, it is vital for Durex® to keep up with evolving trends in consumer preference when it comes to sexuality and we strive to provide products that match these trends," said Tonya Cramer, Associate Brand Manager, Durex® Consumer Products. "The GenSex Survey's youth-centric design and delivery helps us capture the voice of young adults and better understand their sexual feelings and experiences."
Other Revelations About GenSex
On Losing Virginity
On Infidelity
On Definitions of Sex
On Contraception
About the GenSex Survey
The GenSex Survey asked adults 18 and older about sexual education, lifestyles and preferences. The survey was commissioned by Durex® Consumer Products as part of its 2002 Durex® Global Sex Survey. A total of 2,548 men and women were surveyed, with only 300 of the respondents older than 30. Responses to the survey were analyzed by sex, age and relationship status providing a more detailed picture of behavioral differences. Data was collected online.
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Thu Feb 6, 5:46 PM ET
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NEW YORK (Reuters Health) - Young black men who have sex with other men are more likely than their peers to be closeted, meaning they have not disclosed their sexual orientation to others, according to a new report from the Centers for Disease Control and Prevention (CDC).
And while such closeted men don't have a higher risk of HIV and other sexually transmitted diseases (STDs) than "out" gay and bisexual men, "nondisclosers" are less likely to know that they carry the virus that causes AIDS and are more likely to have recently had sex with a woman, the CDC survey suggests.
The findings make it clear, the report's authors say, that more effort should be made to test closeted men and their sex partners--male and female--for HIV and STDs.
Men who have sex with other men but don't disclose their sexual orientation "are thought to be at particularly high risk for HIV infection because of low self-esteem, depression or lack of peer support and prevention services that are available" to men who are more open about their homosexuality, D. A. Shehan of the University of Texas Southwestern Medical Center in Dallas and colleagues write.
But the risks of HIV and other STDs that such men actually face are "unknown," the researchers note in the February 7th issue of the CDC's Morbidity and Mortality Weekly Report.
To investigate, the researchers evaluated a survey examining the sexual practices and attitudes of 5,589 men who have sex with men. Men aged 15 to 29 living in six US cities participated in the survey, which was conducted between 1994 and 2000.
All of the men also underwent testing for HIV and hepatitis B, a sexually transmitted disease that can harm the liver.
In all, 637 men reported that they were "not out to anyone" about the fact that they had sex with men. Of this group, 55% were between the ages of 15 and 22.
Tests revealed that overall, 8% of the closeted men were HIV-positive compared to 11% of men who were open about their sexuality.
Among blacks, the prevalence of HIV infection was 14% among closeted blacks compared to 24% of openly gay or bisexual blacks. About 18% of blacks said they had not disclosed their sexual orientation compared with 8% of whites, and 14% of black nondisclosers were HIV infected compared with 5% of nondisclosers of other ethnicities.
The researchers also found that among HIV-positive men, those who were closeted were less likely than "out" men to be aware of the infection. Of those with HIV, 98% of nondisclosers were unaware of the infection compared with 75% of those who were openly gay.
Although this study didn't find closeted men faced a higher HIV risk, "the data suggest that a substantial portion of nondisclosers are infected with HIV and other STDs and are at high risk for transmitting these infections to their male and female sex partners," the CDC states in an accompanying editorial note.
The survey finding that more than one in three closeted men reported having had sex with women recently suggests that such "nondisclosers" may play a major role in spreading HIV and STDs to women, according to the CDC.
This might be particularly true for closeted black men, the CDC adds, as about one in five were positive for hepatitis B and about one in seven were HIV positive.
"The findings in this report suggest that public-awareness and prevention programs should be developed" for closeted men "to reduce internalized homophobia and other factors that influence nondisclosure," the CDC concludes.
SOURCE: Morbidity and Mortality Weekly Report 2003;52:81-85.
| Press Release | Source: Medivir |
Friday February 7, 5:09 am ET
Medivir's HIV & Hepatitis B Antiviral MIV-210 Enters Oral Multiple Dose Study
The goal of the study is to further ensure the compounds safety after multiple oral dosing and to further investigate its good oral bioavailability and pharmacokinetic properties to establish dose levels for entering phase II trials.
MIV-210 is a polymerase inhibitor effective against both multiple drug resistant HIV-1 and hepatitis B (HBV) in vitro and in vivo. The development plan for the compound includes clinical phase II studies in both HIV and hepatitis B patients. Medivir has a second drug in clinical development targeting multidrug resistant HIV-1, namely MIV-310 (alovudine) which is in clinical phase II. MIV-210 and MIV-310 have shown synergistic effects against HIV-1 in vitro.
There are more than 1.5 million of HIV/AIDS patients in the Western world of whom a considerable portion harbour drug resistant HIV-strains. The number of patients with multiresistant HIV is increasing rapidly and there is a considerable need for new antivirals. Current HIV therapy employs combinations of several antivirals from different classes with different resistance profiles. MIV-210 has in vitro been found to inhibit HIV-1 strains that are resistant to other polymerase inhibitors. Sales of polymerase inhibitors against HIV-1 amounted to $3.5 billion US during 2001.
There are more than 350 million chronically infected hepatitis B patients worldwide, of whom 5-6 million are in the Western world and approximately 100 million are in China. The number of patients treated is comparatively low but growing rapidly as new antivirals are introduced. The emergence of HBV strains resistant to the available medications will increase the need for new antivirals. Sales of HBV antivirals in 2001 were approximately $0.6 billion US despite their limited efficacy.
| Press Release | Source: ViroLogic, Inc. |
Friday February 7, 8:01 am ET
The four oral presentations and 16 poster sessions by scientists at ViroLogic and their collaborators at pharmaceutical companies, medical centers and research institutions in the United States and abroad represent "a substantial amount of important, cutting-edge data," according to Nicholas Hellmann, M.D., Vice President of Clinical Research at ViroLogic. "ViroLogic is a world leader in defining how best to apply resistance testing and replication capacity assays to the management of anti-retroviral therapy," he said.
Christos Petropoulos, Ph.D., Vice President of Research and Development at ViroLogic commented, "The extensive range of presentations shows that ViroLogic continues to contribute significant research at the forefront of the drug resistance testing field. Our technologies are helping to improve patient management and facilitating the development of new drugs."
ViroLogic's replication capacity assay, known as PhenoSense(TM) RC, is the only commercially-available measurement of viral "fitness;" i.e., the ability of patient-derived HIV isolates to replicate in the absence of anti-retroviral drugs. Changes in the replication capacity of the virus, which often occur after an alteration in the susceptibility of virus to drug therapy, may indicate a change in the rate of disease progression. Data from many recent studies increasingly suggest that replication capacity is an important, clinically useful parameter in HIV infection and AIDS.
In several of the studies being presented at the conference this year, PhenoSense RC was used to explore the relationship between replication capacity of HIV and clinical parameters (e.g., viral load, drug susceptibility and CD4 counts) in recently-infected or treatment-experienced patients. This body of research supports the potential diverse clinical applications of PhenoSense RC as a significant new prognostic and decision-making tool for the management of newly-infected patients and treatment-experienced patients failing therapy.
PhenoSense RC and ViroLogic's new PhenoSense HIV Entry assay are the only commercially-available tests of their kind, determining phenotypic drug susceptibility to anti-retroviral agents with established and new mechanisms of action. The novel PhenoSense Entry Assay can be used to measure HIV susceptibility to experimental inhibitors of entry (e.g., inhibitors of attachment, co-receptor antagonists, and fusion inhibitors) co-receptor tropism and neutralizing antibody responses. Two presentations at the conference this year report on the use of the PhenoSense Entry Assay in the Phase III clinical trials of enfuvirtide, a fusion inhibitor to assess drug susceptibility in viruses before starting therapy and to detect the emergence of resistance. A third presentation describes the use of the PhenoSense Entry Assay in a clinical trial of PRO 542, an antibody-based inhibitor of HIV attachment to cells. A fourth presentation details the use of the PhenoSense Entry Assay in preclinical studies of AMD3100 (a CXCR4 antagonist) and Compound A (a CCR5 antagonist).
An expanding number of studies that utilized the PhenoSense(TM) HIV Assay have validated the sensitivity, accuracy, and precision of the assay and further clarified the utility of the technology in patient management. In one of the presentations, ViroLogic scientists will describe the use of PhenoSense HIV to investigate the phenotypic susceptibility and define the clinical cut-offs (i.e., clinically relevant levels of drug resistance) in patients treated with a regimen containing the two commonly-prescribed protease inhibitors, indinavir and ritonavir. Another study of more than 2,000 clinical isolates of wild-type virus defines the natural variability of drug susceptibility to all marketed antiretroviral drugs among these viruses and demonstrates the superior performance of the PhenoSense assay compared to other phenotypic assays. Another study describes the use of the growing ViroLogic database of phenotypic and genotypic results, which are derived from routine patient testing, in the analysis of common drug resistance patterns to predict drug susceptibility to reverse transcriptase inhibitors. Two other presentations demonstrate the utility of PhenoSense HIV in studying susceptibility to the investigational protease inhibitors, atazanavir and RO033-4649.
Key presentations featuring ViroLogic's assays include:
-- High Replication Capacity is Associated with High Baseline Viral Load
in Untreated Subjects with Primary HIV Infection, Dr. S.J. Little,
University of California, San Diego.
-- Discordant CD4/VL Response to NNRTI and Protease Inhibitor (PI)-Based
Antiretroviral Therapy (ART) is Associated with CCR-5 Tropism and
Differing Levels of Replication Capacity, C. Hicks, Duke University
Medical Center, Durham, NC.
-- Baseline (BL) and on-Treatment Susceptibility to Enfuvirtide seen in
TORO-1 and TORO-2 Through 24 Weeks, M.L. Greenberg, Trimeris,
Durham, NC.
-- Continued Reverse Transcriptase Inhibitor Therapy is Sufficient to
Maintain Short-Term Partial Suppression of Multi-Drug Resistant
Viremia, S.G. Deeks, University of California, San Francisco.
-- Distribution of Phenotypic Drug Susceptibility among > 2000 Wild Type
Viruses, N.T. Parkin, ViroLogic, South San Francisco, CA.
About ViroLogic
ViroLogic is a biotechnology company advancing individualized medicine by discovering, developing and marketing innovative products to guide and improve treatment of serious viral diseases such as AIDS and hepatitis. The Company's products are designed to help doctors optimize treatment regimens for their patients that lead to better outcomes and reduced costs. The Company's technology is also being used by numerous biopharmaceutical companies to develop new and improved antiviral therapeutics and vaccines targeted at emerging drug-resistant viruses.
Certain statements in this press release are forward-looking, including statements relating to expected proceeds from financing activities. These forward-looking statements are subject to risks and uncertainties and other factors, which may cause actual results to differ materially from the anticipated results or other expectations expressed in such forward-looking statements. These risks and uncertainties include, but are not limited to, the risks that preliminary investigations initiated by governmental agencies may continue for a prolonged period and may not be concluded in the manner expected by ViroLogic, whether ViroLogic's products will achieve market acceptance, the timing of pharmaceutical company clinical trials, whether payors will authorize reimbursement for its products, whether the Company will be able to expand its sales and marketing capabilities, whether the FDA or any other agency will decide to regulate its products or services, whether the Company encounters problems or delays in automating its processes, whether it successfully introduces new products, whether others introduce competitive products, whether intellectual property underlying its PhenoSense technology is adequate, whether it is able to build brand loyalty and expand revenues, and whether ViroLogic will be able to raise sufficient capital. For a discussion of other factors that may cause ViroLogic's actual events to differ from those projected, please refer to the Company's most recent annual report on Form 10-K and quarterly reports on Form 10-Q, as well as other subsequent filings with the Securities and Exchange Commission.