There is no cure for an HIV infection. Even with the currently available antiviral combination therapies, the virus cannot be removed from the body and the HIV genetic information cannot be removed from the cell nucleus, but a significant increase in survival time (compared to untreated HIV infection) is possible. Immediately after the diagnosis of an HIV infection, counseling and support as well as possibly psychotherapeutic measures to cope with the new life situation are in the foreground. Antiviral therapy has so far been carried out depending on the CD4 cell count and viral load. However, new studies show that starting treatment as soon as an HIV infection is established significantly reduces the risk of transmission within a relationship. Note:Human Immunodeficiency Virus is often abbreviated as HIV by AbbreviationFinder.
When AIDS was first described, there were practically no antiviral drugs (antivirals to inhibit virus replication). Therefore the treatment of AIDS-associated diseases was in the foreground. In the case of Pneumocystis carinii pneumonia, toxoplasmosis that causes severe brain damage, and fungal infections, the development of new drugs and treatment approaches have made significant advances in the treatment and prophylaxis, while in the case of other bacterial infections (e.g. atypical mycobacteriosis, for which there are up to there are hardly any effective drugs today) only minor therapeutic successes have been recorded.
Even before highly effective combination therapies directed against HIV became available, antiviral therapies or prophylaxis against infections with herpes and cytomegaloviruses could be developed. The treatment of tumor diseases basically follows similar principles as the treatment of tumor diseases in patients without HIV infection, but leads to significantly less tumor regression or is associated with a higher relapse rate. For AIDS-associated Kaposi’s sarcoma there is no effective treatment to date. In addition to the treatment of infections and tumors, the treatment of symptoms such as weight loss, diarrhea without evidence of a pathogen and pain were in the foreground, whereby considerable success was often achieved here using traditional medical methods.
Antiretroviral drugs
The multiplication (replication) of HIV can be inhibited at various starting points. The antiretroviral drugs available today can be divided into five substance classes:
- Nucleoside analogs (nucleoside reverse transcriptase inhibitors, NRTIs), e.g. B. zidovudine, didanosine, stavudine, lamivudine or abacavir. With the drug azidothymidine (AZT, today’s name zidovudine), antiretroviral therapy targeted against HIV became possible for the first time in 1987.
- Non-nucleoside analogs (non-nucleoside reverse transcriptase inhibitors, NNRTIs), e.g. B. nevirapine or efavirenz.
- Nucleotide analogs (nucleotide reverse transcriptase inhibitors, NtRTIs), e.g. B. Tenofovir, inhibit the viral enzyme reverse transcriptase by incorporating a defective building block and thus suppress the virus replication.
- Protease inhibitors (e.g. saquinavir, ritonavir, lopinavir, atazanavir or nelfinavir), which inhibit the maturation of infectious HIV particles and the development of the virus structure (core protein), were introduced like the NNRTIs in 1996. In connection with the NRTIs, a highly effective antiretroviral combination therapy (HAART) became available with these drugs.
- Fusion inhibitors (e.g. T-20), which are supposed to prevent the binding of HIV to or fusion with target cells, were approved in 2002.
With chemokine receptor blockers (e.g. CCR5 inhibitors) and integrase inhibitors (raltegravir), active ingredients from other substance classes with new points of attack are under development.
The aim of antiretroviral therapy is to suppress the multiplication of HIV as permanently and completely as possible and thus lower the viral load, since according to today’s opinion, the damage to the immune system is caused by a high viral load and the continued multiplication of the virus, and also to the development of resistances to prevent the drugs used as much as possible. The standard today is a combination therapy consisting of at least three antiretroviral agents (“highly active antiretroviral therapy”), or HAART for short. Because the body has to have sufficiently high concentrations of active ingredients at all times, it is necessary to take the medication on a regular basis.
It is important to begin treatment before serious complications or AIDS-defining illnesses develop. New studies even show that starting treatment early can lower the risk of transmission to the partner. There is a clear indication for treatment for patients with HIV-related symptoms and HIV-associated diseases. An argument against starting treatment early is that daily drug intake can become a significant physical and psychological burden, especially if it leads to a greater feeling of illness and a reduction in quality of life in patients who are still symptom-free, e.g. B. by side effects, contributes. The current German-Austrian therapy guidelines for antiretroviral therapy in adults,
Limiting factors of antiretroviral therapy are, on the one hand, the build-up of resistance to the drugs used, which can lead to a complete loss of effectiveness, and the sometimes massive side effects of the drugs: In addition to complaints in the gastrointestinal tract (diarrhea, flatulence, nausea), skin reactions, mental disorders (e.g. nightmares, depression) or interactions with other drugs occur in a high percentage of those treated to varying degrees and degrees of long-term side effects that affect the peripheral nervous system (polyneuropathy), hormone, carbohydrate and lipid metabolism, affect the distribution of fatty tissue, bone strength or the function of individual organs (e.g. liver, kidneys).
Further therapeutic approaches
Immunotherapeutic approaches are predominantly in the experimental stage, which pursue the goal of strengthening the body’s own immune response against HIV or functional failures of the immune system, e.g. B. by administering interleukin-2 (cytokines) to stimulate the formation of new helper cells to compensate. Therapeutic vaccines aim to stimulate the cellular immune response by eliciting neutralizing antibodies. Various attempts, e.g. B. with immunoglobulins or envelope proteins from the virus envelope, have so far not proven to be successful.
»Genetic vaccines« under development with single or multiple viral genes, which are administered as DNA or in safe vectors, are intended to inhibit virus replication in combination with immune-stimulating cytokines. Current research is taking place in the field of stem cell transplantation and gene therapy.
