The type 2 diabetes drug metformin can also help people with HIV

• Research suggests that metformin may help reduce the viral reservoir in HIV patients.
• Metformin is currently used to treat type 2 diabetes.
• It appears to reduce inflammation, which may reduce the risk of metabolic diseases.
• It can also make it more difficult for HIV to evade the immune system.
• Metformin may help increase the effectiveness of antiretroviral drugs in the future.

Canadian researchers say the type 2 diabetes drug metformin could help shrink or even completely eliminate the viral reservoir in people living with the human immunodeficiency virus (HIV) while also taking antiretroviral therapy.

The authors of September 2024 studypublished in the magazine iSciencestate that previous studies showed improvements in immunity and a reduction in inflammation when people took the drug for three months.

In the current study, they found that metformin increased the number of cells containing the HIV virus while preventing the virus from leaving the cells.

They point out that these effects could be used to enhance the effectiveness of antiretroviral drugs.

This is important because although antiretroviral therapy can reduce viral replication to undetectable levels, it cannot completely eradicate the virus.

Although these drugs can improve people's quality of life, the remaining viral reservoir can lead to chronic inflammation and associated diseases such as cardiovascular disease, cancer and metabolic disorders.

The authors explain that metformin is able to inhibit the activity of the molecule mechanistic target of rapamycin (mTOR).

In their study, this inhibition helped slow HIV replication in the CD4 gene.⁺ This suggests that metformin may help reduce a person's viral load.

The researchers explain that metformin also causes overexpression of the BST2 protein, which helps bind virions (the infectious form of the virus) to the surface of infected cells.

This allows the immune system to locate them and send antibodies to attack them.

“Metformin does this by increasing the number of HIV-infected cells to expose them to the HIV drug,” he explained. “So metformin seems to help the HIV drug work more effectively.”

However, Bosa-Osorio, who was not involved in the study, pointed out that these studies were only conducted in the laboratory.

“So the reality is that the evidence needs to be at eye level,” he said. “That means clinicians need to move on to clinical trials that can tell us more about whether what they see in vitro is applicable to actual patients.”

John Lowe, MD, a physician at Restore Care who was not involved in the study, said that while metformin is primarily used to lower blood sugar levels in people with type 2 diabetes, it is also effective as an anti-inflammatory agent.

“Inflammation is important in HIV because it contributes significantly to the persistence of the virus. Metformin can help to dampen this inflammation and thus help the virus escape,” he said.

Lowe added that this reduction in immune activity could make it more difficult for virus reservoirs to persist.

“In addition, metformin may be useful in HIV treatment because it reduces insulin resistance and thereby reduces the chance of suitable conditions for HIV reproduction,” he explained.

If future research bears fruit, Lowe says it could change the way HIV therapy is delivered.

“Today's therapies can effectively suppress viral replication, but cannot eradicate the virus. Therefore, the patient needs medication for the rest of his life,” he said.

Lowe also noted that metformin has a positive safety record and could make HIV treatment more cost-effective.

This would also broaden the range of possible treatments for the disease, he added, and for some people, such as diabetics, it could reduce the number of medications that would need to be administered.

“If the results of antiretroviral therapy were positive, it would not be surprising if metformin continued to work,” he said.

“This study suggests the possibility of using metformin to achieve a faster response to the drugs we currently use to fight HIV,” added Bosa-Osorio.

He explained, however, that it will not replace these drugs because it does not appear to directly affect the virus, although it may increase the effectiveness of antiretroviral drugs.

“And because metformin also has anti-inflammatory effects, it may also help alleviate cardiovascular disease, which HIV patients are prone to, since HIV is a pro-inflammatory disease,” concluded Bosa-Osorio.

A new study reports that the type 2 diabetes drug metformin may help HIV-infected people taking antiretroviral drugs.

A previous study found reduced inflammation and improved immunity in people after taking metformin for three months.

This is important because the chronic inflammation associated with HIV puts patients at higher risk for cardiovascular disease, diabetes and metabolic disorders.

Metformin also appears to induce changes in the immune system that make antiretroviral drugs more effective at reducing the viral reservoir.

Although this has so far only been proven in the laboratory, experts say that metformin could one day become a valuable addition to antiretroviral therapy.