AB Science SA announced that Health Canada has granted eligibility for reconsideration request for masitinib in amyotrophic lateral sclerosis (ALS). The reconsideration process will re-examine, with new assessors, the decision based on information that was included in the original submission. A Notice of Deficiency-Withdrawal (NOD/w) was issued on February 19, 2024 by Health Canada regarding the New Drug Submission (NDS) for masitinib in the treatment of ALS.

The intention to submit a reconsideration request was based on the arguments summarized in the press release dated 26 February 2024. Health Canada and AB Science have held a meeting to discuss the reconsideration process. AB Science is working closely with the agency to facilitate the review of masitinib conditional approval in ALS.

AB Science has 45 days to file the reconsideration request. The pivotal argument is on the treatment of missing data. Various sensitivity analyses show that study AB10015 was successful at week 48 when masitinib missing data are imputed as a placebo, which is recognized as a highly conservative methodology for missing data imputation (i.e., jump-to-reference).

Rerandomization calculation, which ignores whether the data distribution is linear or not, was also successful. Furthermore, the Combined Assessment of Function and Survival (CAFS) analysis showed a p-value of 0.078, even though study AB10015 was not powered for this endpoint. A related time-to-event endpoint, Progression Free Survival (PFS), did show significant improvement in favor of masitinib.

Additionally, in the subgroup of patients with ?ALS prior to any loss of function?, a logically defined cohort based on masitinib?s mechanism of action, a long-term median overall survival (OS) benefit of +22 months (p=0.0192) was observed.