Impact Areas: HIV/AIDS-How Do ARVs Really Work?

Graph Source: http://www.avert.org/universal-access.htm 

Graph Source: http://www.avert.org/universal-access.htm

We hear a LOT about ARVs, but it’s often something we simply refer to when discussing HIV/AIDS treatment. We’ll take this week’s blog post to examine an essential, though sometimes overlooked, question among HIV educators and WC camp participants: How do ARVs actually work?

As most of you know, HIV is a retro-virus that attacks and kills the CD4 cells of a host’s immune system in order to reproduce. ARVs work by slowing, or even reversing, the progress of HIV.  Different ARVs work to do this in different ways. For example, the group of ARVs known as Entry Inhibitors work to block HIV from replicating in the DNA of a host cell.

Antiretroviral drugs (ARVs) are the most common method of treatment for HIV and AIDS. While ARVs cannot cure an infected person, they can significantly lengthen and improve the life of someone with HIV/AIDS. There are currently more than twenty approved ARVs worldwide, although the availability and licensure varies across countries.

Essentially, the goal of ARVs is to reduce and/or slow the replication of HIV in the body and allow the immune system to stabilize and recover.

When to start? There are quite a few factors that determine when an infected person should start taking ARVs. A medical professional must first assess all existing medical conditions (especially hepatitis, TB and pregnancy), current medications (including traditional and herbal), weight, and emotional/psychological readiness. The World Health Organization currently recommends that people living in areas of limited health system capacity and resources (like Malawi) start taking ARVs when their CD4 count drops to 350cells/mm3. In places where medical care is readily available, patients may begin ARV treatment at a much earlier stage of the disease.

Once started, ARVs must be taken every day for life. If the ARVs are not taken daily, the chances of acquired resistance, when the HIV virus becomes resistant to current ARVs, increases. Adherence is a major obstacle in many developing countries (see graph).

A few aspects of one’s life must be taken into account when deciding on the best choice of therapy. Since someone on ARVs must take their medicine at the same time every day, they must have a schedule that allows them to do so. Some drugs have specific food restrictions that must be taken into account. Potential drug interactions and special handling requirements must also be planned for so as to avoid complications.

Combination therapy: taking two or more ARVs at the same time to reduce the chance of resistance and increase strength. Taking three or more ARVs is sometimes called highly active antiretroviral therapy (HAART).

When a patient first begins ARV treatment, the combination of drugs is called first line therapy. If side effects are intolerable or if HIV becomes resistant, there is usually a change of drugs to second line therapy. Normally, second line therapy includes at least three new drugs.

Some possible side effects of ARVs include diarrhea, nausea, vomiting, rash, lipodystrophy (losing or gaining of body fat), appetite loss, central nervous system effects (including dizziness, mood changes, depression, anxiety and paranoia), fatigue, insomnia, weakness, frequent urination, increased thirst, kidney damage, liver damage, pancreas damage, or nerve damage.

So what does all of this mean for Malawi?

• Treatment requirements recently raised CD4 counts (from 230 to 250 in 2010). This is expected to double the number of Malawians eligible for treatment.
• The WHO has switched the ARVs Malawi will distribute. The new ARVs will reduce side effects and prolong the lives of those taking the drugs.

Submitted by: Karen Clark, WC Coordinator

Sources

• Avert.org
• http://www.aidsmeds.com/archive/Integrase_1687.shtml

**If you'd like to submit a post concerning one of 3 Impact Areas-HIV/AIDS, Environmental Issues or Gender Equality-, please email info@worldcampforkids.org or katy@worldcampforkids. Excerpts from current undergrad and grad research papers, discussions from classes, thoughts on articles, etc. are encouraged!**