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Raltegravir (also known as Isentress) is an oral treatment used to treat HIV. It was tested as a treatment for relapsing MS, but initial results have shown no benefits.

Current phase of trial:
phase 2
Type of MS:
Relapsing MS

Find out more about raltegravir

How does raltegravir work?

Raltegravir is an antiretroviral treatment – a drug that can fight off certain viral infections. It works by stopping the virus creating more of itself (replicating). Raltegravir has been used as to treat HIV for over a decade.

There is now evidence that viruses like Human Endogenous Retrovirus (HERV) could be involved in causing or triggering MS. This has led researchers to investigate if raltegravir may alter course of relapsing MS by controlling HERV infection.

How is raltegravir taken?

Raltegravir is a tablet taken twice a day.

Latest research

The INSPIRE trial

This phase 2 trial involved 24 people with relapsing MS, who took raltegravir for three months. Initial results announced in September 2016 showed that raltegravir did not reduce MRI activity.

What are the side effects of raltegravir?

Raltegravir has been used to treat HIV for over a decade and is generally very well tolerated. The most common side effects include trouble sleeping, headache, dizziness, nausea and tiredness.

How does raltegravir compare with current treatments?

Raltegravir has not been directly compared to other treatments for MS.

When is raltegravir likely to become available?

Raltegravir is already licensed for some conditions, but not for MS. As the phase 2 INSPIRE trial failed to meet its primary endpoint, it's currently not clear what will happen next for raltegravir.