Promising results from Phase 1/2 clinical trial of tofersen

July 9, 2020 – A study published today in the New England Journal of Medicine shows that an experimental drug, called tofersen, has promise for treating a genetic form of ALS caused by mutations in the gene SOD1.

Results from the Phase 1/2 clinical trial, sponsored by the pharmaceutical company Biogen, revealed that tofersen was safe and able to lower levels of the toxic SOD1 protein thought to contribute to disease progression. The preliminary data also showed potential for slowing loss of function and preserving neuronal health. Canadian researchers have played a key role in the studies so far as Dr. Angela Genge (Montreal) and Dr. Lorne Zinman (Toronto) have been involved since the beginning. The positive results from this study led to launch of the Phase 3 VALOR study that will further test the safety and effectiveness of tofersen and is ongoing at a number of sites globally, including at four Canadian sites: Calgary, Edmonton, Toronto and Montreal (Neuro).

If the Phase 3 trial is successful and tofersen moves forward as a new and proven treatment for ALS, it will directly benefit the small percentage of ALS patients who have a mutation in the SOD1 gene. However, the lessons learned from this pivotal study will help researchers when developing new approaches to treating all forms of ALS.