Skip to content

Page last checked: 20th March 2023
Last updated: 30th May 2018

The lower motor neurons in the spinal cord specifically deteriorate in SMA patients. Messages from the spinal cord can no longer be efficiently passed to their target muscles, which makes movement difficult. Muscles then waste or atrophy due to lack of use.

Neuroprotection aims to support motor neurons by restoring their function and / or preventing their death. Unlike approaches that target the SMN1 or SMN2 genes, this approach does not address the underlying genetics of SMA. However, it could be readily used in combination with therapies that do indeed attempt to restore SMN protein levels, such as SMN1 gene therapy.

The main neuroprotective strategy currently being studied for SMA is based on looking for neuroprotective small molecules that help nerve cells to stay alive and functional.

Olesoxime was a small molecule drug first identified and developed by the French pharmaceutical company Trophos, and was the main neuroprotective chemical being tested as a potential treatment for SMA. Available in liquid form, enabling easy oral administration. Olesoxime had been shown to protect nerve cells from damage in cell culture, while improving neuronal growth and function, however later results led to further investigations ending in May 2018.


May: Roche’s Community Update: Ending Trials of Olesoxime


December: Catalyst Pharmaceuticals announced that they were to investigate the potential of a drug called Firdapse (also called amifampridine and 3,4-diaminopyridine)in a small-scale, proof-of-concept phase 2 clinical trial that would include approximately 12 ambulatory SMA patients. Firdapse had been approved in Europe for the treatment of a neuromuscular disease called Lambert Eaton Myasthenic Syndrome, or LEMS. Results were expected from this phase 2 study of Firdapse in early 2019.


March: Trophos announced positive results from a two year-long Phase II clinical trial of the drug Olesoxime in SMA patients.

The Phase II double-blind trial of Olesoxime included 165 Type II and non-ambulatory Type III SMA patients aged 3-25, and was performed across 22 centres in seven different European countries. Olesoxime was administered daily in liquid form, facilitating oral delivery to young children, and patients were assessed every three months during the study.


5th April: Trophos pharmaceutical company announced that olesoxime had successfully passed a safety review by an independent group of experts.