Caution still advised despite ever-improving HIV drugs

Caution still advised despite ever-improving HIV drugs
Credit: Keystone

Combination therapies for AIDS are becoming increasingly effective, but they cannot protect against other sexually transmitted illnesses. It is unsafe for patients taking antiretroviral drugs to stop using condoms. This is one of the findings of research conducted in the Swiss HIV Cohort Study, which is supported by the SNSF.

Drugs for HIV, the virus causing AIDS, have existed for more than two decades. Therapies have been continually refined and the standard approach in the West is now a involving various antiretroviral substances. The rationale behind this idea is that the constantly changing virus finds it harder to develop resistances against three or more drugs administered simultaneously.

Less resistance to new drugs

At the beginning of the year, Huldrych Günthard (University Hospital Zurich) and his colleagues from the Swiss HIV showed that new combination therapies are better at keeping viruses in check than the therapies used ten years ago. For the older therapies, resistant viruses developed on average 2.6 times per 100 patient-years (i.e. 100 patients over the course of one year, 50 over the course of two years) while resistance to the newer therapies developed only 1.5–1.9 times. Researchers believe that this improvement is not only the result of greater drug effectiveness – patients also tend to take the drugs more regularly because they have less side-effects.

Dramatic spread of hepatitis C

The continual improvement of combination therapies reduces the risk of . Recently published results of the Swiss HIV Cohort Study suggest that this leads to a false sense of security in certain patients. Figures show that has spread rapidly among HIV-positive gay men during the last few years. While the rate of infection among has remained low (on average 0.4 infections per 100 patient-years), it has risen drastically among : 4.1 persons are infected per 100 patient-years. This rate is 18 times higher than the one recorded in 1998.

Researchers point to the inconsistent use of condoms as the greatest risk factor. While the fear of AIDS has understandably diminished, there may be a tendency now to neglect other sexually transmitted illnesses. "Caution is still called for," says Günthard.

The Swiss HIV Cohort Study

Established in 1988, the Cohort Study aims to generate knowledge about HIV infection and AIDS as well as to improve the care given to patients. All Swiss hospitals specialising in HIV (Basel, Berne, Geneva, Lausanne, Lugano, St. Gallen and Zurich) have collected and analysed data from over 16,000 HIV-positive persons. Currently, more than 8,400 persons are taking part in the Swiss HIV Cohort Study. Almost a third of them are women.

More information: von Wyl V, et al., Swiss HIV Cohort Study (2012). Incidence of HIV-1 drug resistance among antiretroviral treatment-naive individuals starting modern therapy combinations. Clin Infect Dis. 54:131-40

Wandeler G, et al., Swiss HIV Cohort Study (2012). Hepatitis C Virus Infections in the Swiss HIV Cohort Study: A Rapidly Evolving Epidemic. Clin Infect Dis. 55:1408-1416

www.shcs.ch/

Related Stories

New book on HIV from Cold Spring Harbor Laboratory Press

date Dec 15, 2011

The worldwide AIDS epidemic makes research on HIV, the disease processes it induces, and potential HIV therapies among the most critical in biomedical science. Furthermore, the basic biology of HIV infections ...

Recommended for you

HIV prevention and risk behaviors follow weekly patterns

date 12 hours ago

The peak time for seeking information on topics related to HIV, such as prevention and testing, is at the beginning of the week, while risky sexual behaviors tend to increase on the weekends, according to a new analysis by ...

Mathematical model seeks functional cure for HIV

date 14 hours ago

(Medical Xpress)—Individuals with the natural ability to control HIV infection in the absence of treatment are referred to as elite controllers (ECs). Such individuals maintain undetectable viral loads ...

Indiana HIV outbreak, hepatitis C epidemic sparks US alert

date Apr 24, 2015

Federal health officials helping to contain an HIV outbreak in Indiana state issued an alert to health departments across the U.S. on Friday, urging them to take steps to identify and track HIV and hepatitis C cases in an ...

Why are HIV survival rates lower in the Deep South than the rest of the US?

date Apr 22, 2015

The Deep South region has become the epicenter of the US HIV epidemic. Despite having only 28% of the total US population, nine states in the Deep South account for nearly 40% of national HIV diagnoses. This region has the highest HIV diagnosis rates and the highest number of people living with HIV of any ...

User comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.