Current phase of trial: Phase 2
Type of MS: Secondary progressive MS
Find out more about fluoxetine
How does fluoxetine work?
Fluoxetine is a selective serotonin reuptake inhibitor (SSRI). It increases the amount of serotonin, a chemical messenger thought to influence mood, in the brain by preventing it from being absorbed.
Researchers think fluoxetine could be neuroprotective, making it an exciting potential treatment for progressive MS.
How is fluoxetine taken?
Fluoxetine is a tablet.
MS-SMART is a three year trial that will test the safety and effectiveness of three different drugs - fluoxetine, amiloride and riluzole – against a placebo treatment in 440 people with secondary progressive MS. The trial is expected to be completed in 2018.
FLUOX-PMS is a phase 2 trial that involved 134 people with primary and secondary progressive MS. It tested how effectively fluoxetine could slow progression compared to a placebo. Topline results from this trial were announced at a scientific conference in September 2016. Researchers found that fluoxetine did not slow progression compared with placebo.
In 2007, we set up the UK MS Clinical Trials Network (CTN): a group of MS experts tasked with developing and producing clinical trials for progressive MS. The group, funded by the MS Society, carried out £500,000 worth of underpinning research that was needed in order to develop the MS-SMART trial.
Through the work of the CTN, a number of drugs were established as having the potential to be neuroprotective, of which fluoxetine scored particularly highly.
Fluoxetine has shown promise in early phase clinical trials in people with MS. Two trials have tested fluoxetine as a treatment for people with MS (one for relapsing and one for progressive MS). Fluoxetine was found to be safe in the progressive MS trial, and was reported to reduce the number of lesions in the brain in 40 people with relapsing MS.
What are the side effects of fluoxetine?
The side effects associated with fluoxetine in people with MS are currently unknown. Although side effects reported in the early small stage trials included one heart attack in the primary progressive trial (however researchers believe that this is unlikely to be related to the treatment), along with milder effects of drowsiness and fatigue at the start of treatment. In the relapsing MS trial, nausea and drowsiness were reported at the start of treatment.
How does fluoxetine compare with other therapies?
There are currently no treatments for progressive MS.
When is fluoxetine likely to become available?
The MS-SMART trial is due to finish in 2018 and, if the results are positive, fluoxetine would then need to be tested in larger phase 3 trials before it could be licensed.