The International Progressive MS Alliance has received a Letter of Support from the U.S. Food and Drug Administration (FDA), marking a major milestone in the journey towards increasing the number and speed of clinical trials in progressive MS.

The letter from the FDA encourages the exploration and development of further studies on ‘neurofilament light chain’ (NfL), which is a molecule that enters the spinal fluid and blood when nerves are damaged. NfL can be used as a biomarker – an indicator of how the body is functioning and if a treatment is effective. NfL could potentially tell us whether or not an experimental therapy – tested in early clinical trials involving people with progressive MS – is working.

Studies of NfL have been underway to better define how this biomarker may be employed to help detect and predict disease activity and response to treatments, not only in MS but in other conditions. In early phase trials, NfL may give us a better picture of someone’s ongoing disease course and be more responsive to the effects of treatments than traditional detection methods such as an MRI scan.

This is the first time the FDA has provided a Letter of Support for further research on any MS-specific biomarker for use in clinical trials. Because further steps and research are needed for NfL to be approved as an outcome measure, this letter can encourage further development by signalling to industry and other researchers that drug regulators are aware of the evidence supporting this biomarker. The Alliance has also submitted support materials to the European Medicines Agency to request a similar letter from them.

The FDA’s Letter of Support resulted from an application that included a review of published research results on NfL that was compiled by the Alliance’s Fluid Biomarkers Implementation Team, a panel that includes experts from the pharmaceutical/biotech industry, academic research and people living with progressive MS. The team had previously published recommendations outlining evidence and priority research for developing NfL as a biomarker for progressive MS.

Dr. Robert J. Fox, Vice Chair of the Alliance’s Scientific Steering Committee and senior author of the Biomarkers Implementation Team paper said:

‘Receiving this Letter of Support is a critical step that signals to industry sponsors and academic researchers the potential value of including serum neurofilament light as an exploratory outcome measure in clinical trials focusing on progressive MS. Having a simple blood test to quickly track the potential benefits of experimental therapies would be an enormous step forward for people with progressive MS, for whom there are too few therapies.’

The Alliance is also investing in other initiatives to develop biomarkers of therapies for progressive MS, and recently announced funding 19 new Research Challenge Awards to improve the understanding of mechanisms that drive progression, an area where the current lack of knowledge is hindering treatment development.

Find out more about the International Progressive MS Alliance, its goals, track record and international partners.