Behind the counter: Switching to injectables for HIV

Antiretroviral injectables are the newest form of antiretroviral therapy that healthcare professionals can give to people living with HIV.

These long-acting medications allow people to avoid taking oral daily medication to treat HIV. The first antiretroviral injectable medication with Food and Drug Administration (FDA) approval has the brand name Cabenuva. It contains the active ingredients cabotegravir and rilpivirine.

Some other injectable options include lenacapravir (Sunlenca), which is an HIV capsid inhibitor, and ibalizumab (Trogarzo), which is a monoclonal antibody that can treat multidrug-resistant HIV.

Each antiretroviral injectable works in a different way.

Combination antiretroviral therapy

Cabenuva is a combination antiretroviral therapy that includes an integrase inhibitor known as cabotegravir, and a non-nucleoside reverse transcriptase inhibitor (NNRTI) known as rilpivirine.

Integrase inhibitors work by blocking the integrase enzyme that is used by HIV to insert its viral RNA into the host’s DNA. This means blocking the integrase enzyme prevents HIV from replicating.

NNRTIs work by blocking the HIV reverse transcriptase enzyme. This also prevents HIV replication.

Capsid inhibitors

HIV capsid inhibitors, such as Sunlenca, work by blocking the HIV capsid, which protects HIV’s genetic material and the enzymes required for HIV replication. By interfering with the capsid, this drug can interrupt the HIV viral life cycle.

Monoclonal antibodies

HIV monoclonal antibodies, such as Trogarzo, work by binding to the CD4+ T cells and blocking HIV-1 from infecting the CD4+ T cells. This means that HIV monoclonal antibodies help decrease HIV transmission between cells.

There are several benefits of injectables including a decrease in pill burden.

People living with HIV who are on injectable antiretroviral therapy such as Cabenuva do not typically require additional oral antiretroviral therapy. People receive Cabenuva injections every 1–2 months, allowing for less frequency in taking antiretroviral medications.

Injectable antiretroviral therapy can be a better option than oral medication for people who have trouble swallowing medications or experience gastrointestinal malabsorption conditions.

If a person has multidrug-resistant HIV, injectable antiretrovirals such as Sunleca and Trogarzo may be an option to treat HIV.

A physician may recommend injectable therapy for people living with HIV who are on stable oral antiretroviral therapy and whose HIV viral load is less than 50 (or undetectable).

There are also additional factors to consider, such as age, weight, and HIV drug resistance. Injectables are not recommended for use in people with a detectable HIV viral load or who have a new HIV diagnosis.

Depending on the injectable antiretroviral therapy, it is important to note where healthcare professionals give the injection. For example, they give Cabenuva into the muscle in the gluteal region, also called the buttock area.

It consists of two injections every 1–2 months, which a medical professional will give in a clinic setting. The medication stays in the body for several weeks to months after the injection and the amount of the medication slowly decreases over time.

Once a person starts having the injections, it is important they do not miss scheduled appointments to ensure continued efficacy of the treatment, and also to ensure no drug resistance develops if there are missed doses.

The most common side effects of Cabenuva include the following at the injection site:

• pain
• swelling
• bruising
• lumps

These tend to resolve within the first few days after each injection.

Other common side effects include:

• headaches
• nausea
• fatigue
• fevers
• muscle aches
• dizziness

Cabenuva may also cause serious side effects, including the following:

• allergic reactions
• liver problems
• mood changes

It is important for people to inform their physician of all medical conditions, current medications, and allergies so they can make an informed clinical decision before prescribing a new medication.

The main challenge is compliance with the treatment regimen.

To maintain the medication’s efficacy and an undetectable HIV viral load, it is important to consistently attend all treatment appointments.

Missed appointments can lead to a gap in treatment, which can increase the risk of HIV drug resistance. As a result, HIV viral load levels can increase and the immune system can become weak, which may lead to the later stages of HIV.

Currently, no medication can cure HIV. However, injectable antiretroviral therapy can help a person maintain an undetectable HIV viral load and, as a result, have a long and healthy life.

If an antiretroviral injectable stops working, it means there is likely new drug resistance to the treatment. In this situation, it is important for the person to undergo blood tests to identify any HIV drug resistance. This will lead to a change in antiretroviral therapy to find a regimen that will work to bring the HIV viral load to undetectable again.

Dr. Avi Varma is the founder and CEO of Equal Health, a digital health company whose mission is to provide comprehensive healthcare services to the LGBTQIA+ community. She is a board certified family medicine physician and AAHIVM-credentialed HIV specialist experienced in providing HIV PrEP and PEP services, HIV/AIDS management, LGBTQIA+ primary care services, gender-affirming care, and other infectious disease management (hepatitis B, hepatitis C, latent/active TB, STIs, etc).

Dr. Varma is passionate about promoting health equity through caring for the underserved and eliminating health disparities and its determinants that adversely impact marginalized communities.