Bexarotene is used to treat skin cancer, but was also tested as a treatment for MS in a Phase 2 clinical trial.
The results of this trial showed that bexarotene was able to repair myelin in humans. However, participants in the trial experienced some serious side effects so bexarotene will not be taken forward into a Phase 3 study.
- Current phase of trial:
- This treatment was tested in a Phase 2 trial but is not being taken forward into further trials.
- Type of MS:
- Relapsing MS
How does bexarotene work?
Bexarotene was being tested as a drug to repair myelin, the protective coating around nerves that is damaged in MS.
Previous research in the lab found that drugs which target a specific location in the brain (called retinoid X receptors) are able to encourage oligodendrocytes to produce myelin.
Bexarotene binds to retinoid X receptors on oligodendrocytes (myelin-making cells) and therefore researchers wanted to know whether it is able to boost myelin in the brain.
How was bexarotene taken?
Latest bexarotene research
The CCMR One trial
This Phase 2a trial involved 50 people with relapsing MS.
Top line results from this trial were announced at a scientific conference in September 2020. These results showed that bexarotene was able to boost myelin repair in people with MS.
However, bexarotene was very poorly tolerated by participants in the trial. 15% of trial participants chose not to continue with the trial due to the side effects, and 30% of participants were given a reduction in the dose. All participants experienced hypothyroidism (an underactive thyroid gland) and 90% of participants experienced high levels of triglycerides.
When is bexarotene likely to be available?
Due to the serious side effects that participants in the Phase 2 trial experienced, bexarotene will not be taken forward into any further trials.