This summer while everyone was struggling to beat the heat in the U.S., some of us headed south of the equator (where it is winter!) to Buenos Aires, Argentina for the 1st IAS Conference on HIV Pathogenesis and Treatment sponsored by the International AIDS Society (IAS). The conference was held July 8-11, 2001 and was attended by more than 3,000 delegates from all over the world. This conference was organized in response to the need for a small (relative to the World AIDS Conference, which hosts about 13,000) meeting that focused on the latest treatment research and data available for treating physicians.

The sessions focused on antiretroviral drugs and treatment combinations, side effects and toxicities (such as liver and cardiac abnormalities and lipodystrophy), opportunistic infections and co-morbidities (such as hepatitis), immune-based therapies and vaccines, and treatment strategies (such as structured treatment interruptions or STI's). Interestingly, in each of these areas there was an underlying theme -- adherence.

Adherence

Several years ago the use of combination regimens and more potent treatments became the standard of care in the medical community and an ever-increasing norm among patients. Along with these advances came the issue of adherence. How were we going to be able to take complex, multi-pill regimens consistently -- perhaps even for decades? And the big question in the community became "How much adherence is enough adherence?" Well, we finally have some answers to that question. Several studies have now shown that I need to be 95 percent or more adherent to my regimen in order to maximize the effectiveness of my treatments. That roughly translates to about two missed doses a month on a twice-a-day regimen. The studies have also shown that those individuals who are 60-95 percent adherent are more likely to develop resistance to their treatments than those who take their medicines even less. Of course, those who take their medicines even less than 60 percent of the time, are also not likely to receive benefit from their treatments for long either. Which leads us to the next issue.

Potency vs. Durability

How strong (potent) are the drugs vs. how long will the drugs last (durable). Even if a drug is really strong, it may be too hard to take or have too many side effects. Therefore, a drug that is not quite as strong, but is easier to take and adhere to, may last longer for some people. Many of us will be looking at both of these issues when choosing our treatments, especially as we try to find regimens that will work for the long term.

The good news is that regimens are getting easier. There are fewer pills and less food restrictions for some of the protease inhibitors when used with either ritonavir (Norvir) or delavirdine (Rescriptor). Several of the newest drugs are co-formulated (more than one drug combined in a pill). And, there are even a few possible once-a-day treatments (although they are usually combined with twice-a-day treatments, but at least we're getting closer).

Data was released at this meeting showing that many of the triple combination regimens, including a triple nucleoside combination (Trizivir) continue to work well in more than half the people taking them for at least two years. The longest data set we currently have is the Merck 035 study, which still has participants with viral loads below the limit of detection on a combination of Crixivan, 3TC, and either AZT or d4T for more than five years now!

Structured Treatment Interruptions (STIs)

STI's have been a very hot topic for the past year or so. Data was presented at this meeting confirming that this is a complex issue. The theory behind doing an STI is not only will a person have a break from their treatment regimen, but they may also be causing their immune system to begin to respond to HIV infection again without relying on the anti-HIV meds. The hope is that, ultimately, this will make it possible for people to go off their meds for extended periods of time and still keep the virus under control.

Unfortunately, this theory has only worked in a handfull of people who have been monitored closely in clinical trials. In addition, the majority of people who have experienced some degree of success with this have been newly infected and using their first treatment regimen. The take home here is that the reasons to take a break from treatment are the same as they have always been -- toxicities, you need a break, changing meds, or whatever else. We still do not have enough info to suggest that using an STI will enhance someone's immune response nor do we have enough info to even tell someone how to do it. If you are interested in taking an STI, speak to your doctor, look at some information, and try to get enrolled in a clinical trial!

Side Effects and Toxicities

For many of us, this is the issue we struggle with the most. Each new treatment comes with a list of potential side effects usually identified while the treatment is in clinical trials. Fortunately, side effects are not universal. Most of them only happen in 10-20 percent of people. However, as more people take a drug, we discover more rare and long-term complications. In the last couple of years, the death rate has gone down dramatically in places where treatment is accessible. But as people live longer, take the medications longer, and have HIV longer, problems such as heart disease, liver failure, diabetes, lipodystrophy and bone-related disorders such as osteoperosis are becoming more common. It's important to remember that most of the things on this list are more common problems as people age even without HIV.

At this meeting, most of these issues were discussed, but there is still very little understanding of causes, treatments, or prevention to offer. Instead, a reminder that having a thorough review of your medical history as well as family history with your doctor is always a good idea when initiating new treatments. This October there will be an important conference just on lipodystrophy and adverse reactions in HIV disease, which will include both cardiac and bone density issues. We will report on those issues following that meeting.

So, what is the good news? The good news is that there are several new and promising treatments coming down the pike. Treatments are becoming easier to take, with fewer pills, and better combinations. There is finally some significant headway being made in the understanding of the immune system, what resistance really means (good and bad), our ability to monitor the health and well-being of an individual, and new targets for anti-HIV therapies.

Many of the sessions from this meeting are available to be viewed online. For more information, go to the conference website www.aids2001ias.org. If you are interested in more in-depth summaries of specific sessions, you can also go to http://www.thebody.com/confs/ias2001/ias2001.html and look at The Body's conference coverage.

Dawn Averitt is an HIV-positive woman (diagnosed in 1988) and the former Treatment Resource Specialist at AIDS Survival Project and founder of WISE at Project Inform. Dawn is a national AIDS treatment advocate (or treatment geek, as she puts it) and a well know speaker and writer. She completed a 2,167 mile hike of the Appalachian Trail last year to celebrate 12 years of HIV and was recently married. She lives in Asheville, North Carolina.