A human immunodeficiency virus (HIV) diagnosis is no longer the death sentence it once was. Thirty years ago, doctors had little more than comforting words to offer patients who had been diagnosed with the virus. And while there remains no cure for HIV or AIDS, remarkable advancements in treatments and clinical understanding of how the disease progresses are allowing doctors to help their patients live longer, fuller lives. Here, the medicines that are the future of HIV treatment.
How HIV Medications Work
Antiretroviral drugs do not cure HIV. Instead, they suppress the virus and slow its progression in the body. Sometimes, they suppress the virus to undetectable levels, but they do not eliminate the virus from the body. If antiretroviral medication is successful, a person may be able to add many healthy, productive years to his or her life. The person will still be infected and capable of transmitting the virus, but he or she will be able to maintain a higher health quality for a longer period of time. If the medications are not effective, the virus will likely advance more quickly, and the patient may reach the final stages of the infection in fewer years.
The most commonly prescribed U.S. Food and Drug Administration (FDA)–approved antiretroviral medications can be divided into four classes. These are:
- Reverse transcriptase (RT) inhibitors. RT inhibitors interrupt the life cycle of an HIV-infected cell as it tries to replicate itself. Two types of RT inhibitors exist: (1.) Non-nucleoside reverse transcriptase inhibitors (NNRTIs) prevent HIV from making copies of itself. Common NNRTIs include efavirenz (Sustiva), nevirapine (Viramune), and etravirine (Intelence). (2.) Nucleoside/nucleotide reverse transcriptase inhibitors (NRTIs) keep HIV-infected cells from making copies of themselves by interrupting the reconstruction of the disease’s DNA chain. The most common NRTI is abacavir (Ziagen). The most common combination NRTIs are emtricitabine and tenofovir (Truvada) and lamivudine and zidovudine (Combivir).
- Protease inhibitors (PIs) disable protease, a protein HIV needs to make copies of itself. The most common PIs include atazanavir (Reyataz), darunavir (Prezista), ritonavir (Norvir), and fosamprenavir (Lexiva).
- Entry or fusion inhibitors block HIV from entering CD4+ T-cells. These inhibitors include maraviroc (Selzentry) and enfuviritide (Fuzeon).
- Integrase inhibitors disable integrase, a protein that HIV uses to infect CD4+ T-cells. The most common integrase inhibitor is raltegravir (Isentress).
Multidrug Combination Therapy
HIV cells can mutate and become resistant to a single medicine. To avoid this, many doctors will prescribe a combination of medicines. A combination of three or more antiretroviral drugs is called highly active antiretroviral therapy (HAART), and it’s quickly becoming the initial treatment prescribed by physicians for patients with HIV. When HAART was first approved by the FDA in the late 1990s, HIV-related deaths in the United States were cut by more than half within three years. Advances in medicine are also making adherence to HAART much easier by reducing the number of pills a person must take and reducing side effects. The most common HAART treatment consists of two NRTIs and one NNRTI or a protease inhibitor.
In 2012, the FDA approved Stribild, a combination drug that contains four different medications for treating HIV—the drug Truvada (which contains both emtricitabine and tenofovir) and two new drugs, elvitegravir (an integrase inhibitor) and cobicistat. Stribild is one of the first complete regimen treatments for HIV—it’s a single pill, taken once daily, and it cannot be combined with other HIV medications. Together, these four medicines prevent HIV from replicating and lower the overall viral load in the blood.
In 2011, a similar drug, Complera, was introduced and made available for patients with HIV. This single, once-daily pill contains a combination of emtricitabine, rilpivirine, and tenofovir.
Though a promising advancement, not every patient with HIV is qualified to take these combination pills. Talk with your doctor to see if you are, or how you can become qualified.
Drugs on the Horizon
Each year, new therapies are finding stronger and stronger ground as the future for treating and possibly curing HIV/AIDS. A drug class known as maturation inhibitors may potentially prevent HIV from maturing and properly developing. If these drugs work as designed, they could block HIV from merging with healthy cells.