
ANTIRETROVIRAL THERAPY UNPACKED
What Is Antiretroviral Therapy (ART)?
Antiretroviral therapy is the use of HIV medicines to treat HIV infection. People on this treatment take a combination of HIV medicines called an HIV Regimen on a daily basis. This treatment does not cure HIV but helps the infected to live longer healthier lives, reducing the risk of infection.
WHAT IS HIV?
Human immunodeficiency virus (HIV) is a virus that causes the condition acquired immunodeficiency syndrome (AIDS). The virus attacks a specific type of immune system cell in the body, known as CD4 helper lymphocyte cells. HIV destroys these cells, making it harder for your body to fight off other infections. When you have HIV, even a minor infection, such as a flu can be much more severe because your body has difficulty healing.
HIV is transmitted through contact with bodily fluids such as blood, breast milk, semen and vaginal fluids. Sexual contact and sharing contaminated needles can result in the transmission of HIV. Not only does HIV attack CD4 cells, it also uses the cells to reproduce the virus. When the virus has destroyed a certain number of CD4 cells, doctors will call this stage AIDS. HIV does not always multiply rapidly. In some cases, it takes years for a person’s immune system to be affected enough to have symptoms. A person with HIV will often progress through several phases before their condition is considered AIDS. Taking medications carefully can help to slow the disease’s progression. Following is a discussion on how Antiretroviral therapy works, as well the medicines used to manage HIV.
How Does the Therapy work?
Antiretroviral therapy ensures that HIV does not multiply –reducing the amount of HIV in the body. Less HIV means the immune system has increased ability to recover when attacked by infections. Additionally, by reducing the amount of HIV in the body also reduces the risk of transmission.
Which Medicines are Included in the HIV Regimen?
Antiretroviral therapy is made up of a combination of drugs called a Regimen. Selection of this regimen is dependent on several factors such as side effects, drug interactions and the needs of each patient-thus several regimens to choose from. The HIV medicines are grouped in seven drug classes:
Non-Nucleoside Reverse Transcriptase Inhibitor (NNRTI): NNRTIs bind to and block HIV enzymes. Reverse transcription prevents HIV from replicating.
Efavirenz (EVF), Nevarapine (NVP), Delavirdine (DLV), Etravirine (ETR), Rilpivirine (RPV).
Nucleoside Reverse Transcriptase Inhibitor (NRTI): These are similar to NNRTIs in blocking and reversing transcription, reducing replication.
Zidovudine (AZT), Stavudine (d4T), Lamiduvine (3TC), Didanosine (ddl), Abacavir (ABC), Emtricitabine (FTC) and Zalcitabine (ddc).
Protease Inhibitor (PI): Protease inhibitors work in blocking protease. PIs prevent new (immature) HIV from becoming a mature virus that can infect other CD4 cells.
Indinavir(IDV), Nelfinavir(NFV), Saquinavir(SQV) ,Ritonavir(RTV), Lopinavir(LPV/r) , Atazanavir (ATV), Amprenavir (APV) , Darunavir ( DRV), Fosamprenavir (Fapv) and Tipranavir(TPV).
Fusion Inhibitor (FI): Fusion inhibitors block the HIV envelope from merging with the host CD4 cell membrane. This prevents HIV from entering the CD4 cell.
Enfuvirtide (ENF, T20).
CCR5 Antagonist: CCR5 antagonists block the CCR5 receptor on the surface of certain immune cells, such as CD4.This prevents HIV from entering the cell.
Maraviroc (MVC).
Integrate Strand Transfer Inhibitor (INSTI): INSTIs block integrate (an HIV enzyme. Blocking integrate prevents HIV from replicating.
Raltegravir (RAL), Elvitegravir (EVG) and Dolutegravir (DTG).
PK Enhancer.
Cobicistat.
Nucleotide Reverse Transcriptase Inhibitor (NtRTI)
Tenofovir (TDF), Tenofovir (TAF).
Goals of Anti-Retroviral Therapy
Reduced morbidity and mortality associated with HIV infection and its treatment.
Greatest possible reduction in Viral Load (is the number of HIV RNA copies per ml of blood. An important goal of antiretroviral therapy (ART) is to suppress a person’s VL to an undetectable level).
Immune reconstruction
Reduction in HIV transmission.
When To Start ARVs
It is advised that ARV treatment is initiated in everyone living with HIV as soon as possible.
Adults (older than 19): Therapy should be initiated in all adults with severe or advanced HIV at clinical stage 3 or 4 and a CD4 cell count of less than or equal to 350 / mm3.
Pregnant and Breastfeeding: ART should be initiated in all pregnant and breastfeeding women living with HIV, regardless of clinical stage or CD4 cell count. Treatment should be continued lifelong.
Adolescents (10-19): Therapy should be initiated in all adolescents with severe or advanced HIV at clinical stage 3 or 4 and a CD4 cell count of less than or equal to 350 / mm3.
Children (below 10): Children younger than 5 years of age should initiate therapy at stage 3 or 4, with CD4 cell count less than or equal to 750 /mm3.
Children older than 5 years of age should initiate therapy at stage 3 or 4, with CD4 cell count less than or equal to 350 /mm3.
Adults and Children with Tuberculosis: TB treatment should be initiated first, then followed by ART as soon as possible within the first 8 weeks of treatment.
HIV positive patients with profound immunosuppression (CD4 cell count of less than 50/mm3) should take ARVs within two week of initiating TB treatment.
ART should be started in any child with active TB disease as soon as possible and within 8 weeks following the initiation of anti- tuberculosis treatment regardless of clinical stage and CD4 cell count.
Side Effects of ARV Therapy
NNRT: rash, CNS toxicity, Hyperlipidemia, liver enzyme elevation, serious hepatoxicity and stevens-johnsons syndrome.
NrRTI: bone marrow suppression leading to Anaemia/ neutropenia, myopathy, risk of cardiovascular disease, hyper pigmentation, renal injury and reduction in BMD.
INSTI: The medicines are well tolerated.
LIVING WITH HIV
HIV is not a death sentence. Much progress in the medical and technology field has made living and coping with this virus easier. Sticking to your customised regimen and leading a healthy lifestyle is important. Additionally, learning how to live with HIV and getting in touch with a health care team that knows how to manage HIV will assist you to lead a healthy and fulfilling life. Taking care of your overall health can help you deal with HIV.
Take note to never break your daily medicine routine, get regular medical and dental check-ups, follow a healthy diet, exercise regularly, avoid smoking and recreational drug use, reduce your alcohol intake and use condoms during sex. Doing this will help you take care of and protect your health.