Innovate Calgary Background
Primary Biliary Cholangitis (PBC) is a progressive autoimmune liver disorder that ultimately leads to liver failure and death. It has been granted orphan status and affects approximately 1 in 3000-4000 individuals with over 90% of affected patients being female. Existing therapies are limited to ursodeoxycholic acid and the recently approved Ocaliva. However, ~40% of patients are not responsive to ursodeoxycholic acid.
In a retrospective study, the University of Calgary researchers discovered that mirtazapine usage in PBC patients is correlated with better liver outcomes (decompensation, liver transplant, mortality). Further investigations confirmed the protective effect of mirtazapine in a mouse model of autoimmune hepatitis and unravelled the mechanism through which mirtazapine acts. Interestingly, the mechanism may be applicable to a number of other common autoimmune diseases.
The atypical antidepressant mirtazapine is hepatoprotective in a mouse model of immune-mediated hepatitis. Almishri, W. et al. Journal of Hepatology , Volume 68 , April 2019.
The Antidepressant Mirtazapine Activates Hepatic Macrophages, Facilitating Pathogen Clearance While Limiting Tissue Damage in Mice. Rachelle, D. et al. Frontiers in Immunology, Volume 11. November 2020.
Orphan disease designation
Excellent side effect profile for mirtazapine
Targeted to ursodeoxycholic acid non-responders (40% of patients)
UofC researchers have direct access to 20% of PBC patients in Canada and the majority of Canadian patients through their networks
Clinical trial protocol for 12 week phase II can be conducted at a cost of CAD$700,000 using Remeron
Primary biliary cholangitis
Other autoimmune diseases (currently being investigated)
Innovate Calgary is seeking to license this approach to partners that can help reformulate the existing generic compound and to sponsor the clinical trial.