In Canada, more than 1-in-10 people will suffer a form of major depression at some point in their lives. Drug therapy is often used to treat major depressive disorder (MDD) and there are more than 35 antidepressants available in Canada. Despite this, many people with depression have challenges finding a treatment that relieves their symptoms and does not cause side effects. For more than half of those with MDD, the first medication prescribed is not effective. This may lead people to discontinue treatment, which can result in poorer long-term outcomes and higher overall costs. 

An individual’s genetic makeup can affect whether particular drugs work for them and whether they cause side effects. Pharmacogenomic (PGx) testing aims to use genetic information to guide medication selection and dosing. In other words, it uses information about a patient’s genetic makeup to find a helpful medication faster and avoid severe side effects. This test is not currently offered through the public health system in Canada. Results from this team’s previous project demonstrated that PGx testing could be beneficial for patients and lead to cost-savings for the health system.  

In this project, the team aims to determine the most appropriate and efficient way to introduce this testing in the British Columbian (BC) health system, including which healthcare professionals might deliver it. To do this, their multi-disciplinary team – importantly, including patient partners with lived experience of depression – will identify possible ways of implementing pharmacogenomic testing from available literature and interviewing pharmacogenomics experts, as well as asking the BC public what is important to them about how PGx data is used. Input from healthcare professionals will be used to develop possible implementation strategies and these will be evaluated considering economic perspectives and preferences of people with lived/living experience, policy and decision-makers. 

This research will guide policymaking around the implementation of pharmacogenomic testing for MDD. If adopted by the BC Ministry of Health, this could help physicians with prescribing decisions, improve the health and quality of life for the many Canadians impacted by MDD, and reduce health service use and associated costs.