Does Biktarvy cause weight gain?

Official answer

by Drugs.com

Key Points

Weight gain is common in patients initiated on antiretroviral treatment (ART). HIV disease can lead to weight loss and demands on energy, so halting HIV replication can lower metabolic needs and lead to weight gain if caloric intake remains the same or increases.

However, some recent studies have suggested that some treatments, including integrase strand inhibitors (INSTIs) such as bictegravir, dolutegravir or elvitegravir may be associated with weight gain in HIV patients.

What do studies say about weight gain with Biktary?

A large, 2019 meta-analysis of randomised trials published in Clinical Infectious Diseases found that some newer antiretroviral therapies (ART), including the integrase strand inhibitor (INSTI) bictegravir, appear to be linked with weight gain, as do newer studies of ART in general.

Investigators looked for an association between demographic factors, ART, disease characteristics and weight gain in previously untreated people living with HIV. The group included over 5,600 patients who received treatment between 2003 and 2015.

Drugs evaluated in the study included:

In the pooled analysis of all treatments, each study group showed some weight gain. The overall median weight gain of 2 kg (4.4 lbs) occurred primarily in the first year of treatment (48 weeks) in 12.8% of treatment-naive patients (never treated with HIV medications). Over a 2 year period, 17.3% of participants gained weight but 30.2% had weight loss.

Statistically significant risk factors linked to weight gain (over 48 weeks) included:

Biktarvy Weight Gain

Bictegravir, a component of Biktarvy, was associated with weight gain in this analysis, as were other integrase inhibitors. INSTI use was linked with more weight gain than were protease inhibitors or nonnucleoside reverse transcriptase inhibitors (NNRTIs).

Participants taking bictegravir or dolutegravir demonstrated similar weight gain. A significant risk of weight gain of more than 10% from baseline was seen with both bictegravir or dolutegravir.

Weight Gain: Integrase Strand Inhibitors (INSTI)

Patients who had a lower CD4 count at study entry had more weight gain. Researchers also reported that weight gain can be linked to a “return to health” effect in patients who had active HIV disease for years.

Why do integrase inhibitors like bictegravir cause weight gain?

As suggested in this research, improved gastrointestinal tolerability and less nausea may play a role with newer agents such as bictegravir or TAF. There may be other biological effects not yet identified, as well as this population may gain weight similar to the population at-large.

Researchers did not find an association between >10% weight gain and metabolic effects such as elevated blood sugar or types 2 diabetes onset. Pre-existing obesity was not found to be a risk factor for weight gain in the meta-analysis.

Other studies have also found a risk of weight gain with integrase inhibitors with a median weight gain of between 1 kg (2.2 lbs) and 4 (8.8 lbs) kg over one to two years of follow-up.

How is Biktary used?

Biktarvy, from Gilead, is an oral, 3-drug combination tablet used to treat immunodeficiency virus type 1 (HIV-1). It contains the integrase strand transfer inhibitor (INSTI) bictegravir 50 mg, along with 200 mg of emtricitabine (FTC) and 25 mg of tenofovir alafenamide (TAF), both HIV-1 nucleoside analog reverse transcriptase inhibitors (NRTIs).

Biktarvy is FDA-approved as a complete regimen for the treatment of HIV-1 infection in adults and children weighing at least 14 kg (31 lbs):

Biktarvy is taken once a day, every day, with or without food. A new lower-dose formulation tablet for children was approved in October 2021.

Three integrase inhibitors are currently approved for use in the US for people living with HIV:

Elvitegravir (Vitekta) as a single agent was discontinued from the U.S. market in 2016.

Other side effects with Biktarvy

The most common side effects with Biktary include:

Hepatitis B (HBV) infection

Biktarvy may worsen hepatitis B (HBV) infection. If you have both HIV-1 and HBV and stop taking this treatment, your HBV may suddenly worsen. Do not stop taking Biktarvy without first talking to your healthcare provider, as they will need to monitor your health.

Other serious side effects for Biktarvy include:

Tell your doctor right away if you get symptoms such as:

These are not all the side effects with Biktary. Tell your doctor immediately if any new or worsening side effects occur during treatment.

Bottom Line

Biktary is not listed as being associated with weight gain in the package insert. However, recent research suggests all integrase strand inhibitors such as bictegravir found in Biktary may be linked with some weight gain.

Studies have demonstrated a median weight gain of between 1 kg (2.2 lbs) and 4 (8.8 lbs) kg over one to two years of follow-up. However, some patients have seen a >10% weight gain.

Mechanisms for weight gain are not well-defined; however, less nausea and better tolerability of newer agents may play a role. Weight gain is also common in patients living with HIV who receive ART for the first time and have a reduction in viral activity and overall improved health.