Pharmacogenomic testing for antidepressants could help reduce the time and cost it takes to find the most effective medication for a patient, according to a new study.
Scientists developed a microsimulation model to evaluate the effectiveness of pharmacogenomic testing for adult patients in British Columbia, Canada, with newly diagnosed moderate to severe major depressive disorder (MDD). The model predicted that testing could result in 37% fewer patients developing refractory depression, 15% more time of patients feeling well, and a health system cost-savings of $956 million CAD over 20 years.
Shahzad Ghanbarian, PhD
“Our study shows that if pharmacogenomic testing guides the prescription of an effective antidepressant, it can reduce the lengthy trial-and-error process many patients experience and dramatically reduce the financial burden on the healthcare system,” Shahzad Ghanbarian, PhD, the lead author and a research analyst at the University of British Columbia’s Centre for Clinical Epidemiology and Evaluation, told Medscape Medical News.
“The next step should be developing implementation strategies and identifying the most suitable healthcare professionals to provide pharmacogenomic-guided care,” she said.
The study was published online on November 14, 2023 in the Canadian Medical Association Journal.
Developing a Model
The World Health Organization has predicted that depression will be the leading cause of disability worldwide by 2030. However, about half of patients don’t respond to the antidepressant that they are initially prescribed, and more than one quarter report adverse effects. Previous studies have found that up to 42% of the lack in response stems from genetic factors that affect medication metabolism.
Pharmacogenomic testing, which uses a blood, saliva, or buccal swab sample, could help identify genetic variants involved in drug metabolism and response as well as guide prescribing and reduce adverse effects, the authors write.
Ghanbarian and colleagues developed a microsimulation model in collaboration with patient partners, clinicians, and the health system to evaluate the effectiveness and cost-effectiveness of pharmacogenomic testing for adult patients with MDD in British Columbia. The model included unique patient characteristics, such as metabolizer phenotypes, and followed the experience of patients through diagnosis, treatment, and recurrence.
According to British Columbia administrative data from 2015 to 2020, the model simulated a population of 194,149 adults and incorporated 40 different antidepressants and other treatments, including electroconvulsive therapy (ECT) and psychotherapy. The research team compared treatment pathways for patients with and without pharmacogenomic testing over 20 years.
Overall, the model showed that pharmacogenomic-guided treatment resulted in higher remission rates and lower discontinuation rates, with 23,216 (37%) fewer patients developing refractory depression and decreased use of resource-intensive treatment options such as ECT and psychotherapy (by 28% and 22%, respectively). According to the model, these reductions would save the British Columbia health system $4926 CAD per patient, or about $56 million CAD over 20 years.
These findings provide a solid economic justification for clinical implementation of pharmacogenomic-guided depression treatment in Canada.
In addition, the model found that patients who underwent pharmacogenomic testing spent 15% more time in the “well” state without depression symptoms and 18% less time in the MDD state with recurrent episodes or refractory depression. In turn, this would mean 1,869 fewer deaths and 21,346 fewer all-cause hospital admissions over 20 years.
Pharmacogenomic testing also led to gains of .064 life-years and .381 quality-adjusted life-years (QALYs) per patient, or 12,436 life-years and 74,023 QALYs for all of British Columbia over 20 years.
From a cost perspective, the $121 million CAD cost of pharmacogenomic testing and $524 million CAD increase in episodic care were offset by a decrease in the cost of refractory MDD care. In sensitivity analyses, upfront investment in pharmacogenomic testing was typically offset after 2 years through lower direct medical costs, and it was also considered a cost-saving measure from that point forward.
“By incorporating the perspectives of patients with lived and living experience into this model, alongside robust data sets, we were able to carefully simulate the treatment journey of people with major depression,” Ghanbarian said. “The simulation model is designed to be flexible and could be applied to other jurisdictions beyond British Columbia, where we might expect to see similar benefits, particularly within a comparable Canadian context.”
Implementing the Model
Now, Ghanbarian and colleagues are interested in potential implementation strategies at a system-wide level. For now, pharmacogenomic tests aren’t offered through the public health systems across Canada, but patients can pay for them through private companies.
“These findings provide a solid economic justification for clinical implementation of pharmacogenomic-guided depression treatment in Canada,” Chad Bousman, PhD, associate professor of physiology and pharmacology at the University of Calgary, told Medscape Medical News.
Chad Bousman, PhD
Bousman, who was not involved with this study, co-authored the Clinical Pharmacogenetics Implementation Consortium guideline for several genotypes and serotonin reuptake inhibitor antidepressants. He and colleagues have also developed and evaluated web-based tools that translate pharmacogenetic data into evidence-based prescribing recommendations.
“The hope is that this work will facilitate investment in the establishment of the necessary infrastructure to ensure Canadians have equitable access to pharmacogenomic testing and ultimately improve mental health outcomes,” he said.
The study was funded by Genome BC, Genome Canada, and Michael Smith Health Research British Columbia. Ghanbarian and Bousman reported no relevant financial relationships.
The Canadian government says it will donate up to 200,000 vaccine doses to fight the mpox outbreak in Congo and other African countries.
It says the donated doses of Imvamune will come from Canada’s existing supply and will not affect the country’s preparedness for mpox cases in this country.
Minister of Health Mark Holland says the donation “will help to protect those in the most affected regions of Africa and will help prevent further spread of the virus.”
Dr. Madhukar Pai, Canada research chair in epidemiology and global health, says although the donation is welcome, it is a very small portion of the estimated 10 million vaccine doses needed to control the outbreak.
Vaccine donations from wealthier countries have only recently started arriving in Africa, almost a month after the World Health Organization declared the mpox outbreak a public health emergency of international concern.
A few days after the declaration in August, Global Affairs Canada announced a contribution of $1 million for mpox surveillance, diagnostic tools, research and community awareness in Africa.
On Thursday, the Africa Centres for Disease Control and Prevention said mpox is still on the rise and that testing rates are “insufficient” across the continent.
Jason Kindrachuk, Canada research chair in emerging viruses at the University of Manitoba, said donating vaccines, in addition to supporting surveillance and diagnostic tests, is “massively important.”
But Kindrachuk, who has worked on the ground in Congo during the epidemic, also said that the international response to the mpox outbreak is “better late than never (but) better never late.”
“It would have been fantastic for us globally to not be in this position by having provided doses a much, much longer time prior than when we are,” he said, noting that the outbreak of clade I mpox in Congo started in early 2023.
Clade II mpox, endemic in regions of West Africa, came to the world’s attention even earlier — in 2022 — as that strain of virus spread to other countries, including Canada.
Two doses are recommended for mpox vaccination, so the donation may only benefit 100,000 people, Pai said.
Pai questioned whether Canada is contributing enough, as the federal government hasn’t said what percentage of its mpox vaccine stockpile it is donating.
“Small donations are simply not going to help end this crisis. We need to show greater solidarity and support,” he said in an email.
“That is the biggest lesson from the COVID-19 pandemic — our collective safety is tied with that of other nations.”
This report by The Canadian Press was first published Sept. 13, 2024.
Canadian Press health coverage receives support through a partnership with the Canadian Medical Association. CP is solely responsible for this content.
HALIFAX – The Nova Scotia government says it could be months before it reveals how many people are on the wait-list for a family doctor.
The head of the province’s health authority told reporters Wednesday that the government won’t release updated data until the 160,000 people who were on the wait-list in June are contacted to verify whether they still need primary care.
Karen Oldfield said Nova Scotia Health is working on validating the primary care wait-list data before posting new numbers, and that work may take a matter of months. The most recent public wait-list figures are from June 1, when 160,234 people, or about 16 per cent of the population, were on it.
“It’s going to take time to make 160,000 calls,” Oldfield said. “We are not talking weeks, we are talking months.”
The interim CEO and president of Nova Scotia Health said people on the list are being asked where they live, whether they still need a family doctor, and to give an update on their health.
A spokesperson with the province’s Health Department says the government and its health authority are “working hard” to turn the wait-list registry into a useful tool, adding that the data will be shared once it is validated.
Nova Scotia’s NDP are calling on Premier Tim Houston to immediately release statistics on how many people are looking for a family doctor. On Tuesday, the NDP introduced a bill that would require the health minister to make the number public every month.
“It is unacceptable for the list to be more than three months out of date,” NDP Leader Claudia Chender said Tuesday.
Chender said releasing this data regularly is vital so Nova Scotians can track the government’s progress on its main 2021 campaign promise: fixing health care.
The number of people in need of a family doctor has more than doubled between the 2021 summer election campaign and June 2024. Since September 2021 about 300 doctors have been added to the provincial health system, the Health Department said.
“We’ll know if Tim Houston is keeping his 2021 election promise to fix health care when Nova Scotians are attached to primary care,” Chender said.
This report by The Canadian Press was first published Sept. 11, 2024.
ST. JOHN’S, N.L. – Newfoundland and Labrador‘s chief medical officer is monitoring the rise of whooping cough infections across the province as cases of the highly contagious disease continue to grow across Canada.
Dr. Janice Fitzgerald says that so far this year, the province has recorded 230 confirmed cases of the vaccine-preventable respiratory tract infection, also known as pertussis.
Late last month, Quebec reported more than 11,000 cases during the same time period, while Ontario counted 470 cases, well above the five-year average of 98. In Quebec, the majority of patients are between the ages of 10 and 14.
Meanwhile, New Brunswick has declared a whooping cough outbreak across the province. A total of 141 cases were reported by last month, exceeding the five-year average of 34.
The disease can lead to severe complications among vulnerable populations including infants, who are at the highest risk of suffering from complications like pneumonia and seizures. Symptoms may start with a runny nose, mild fever and cough, then progress to severe coughing accompanied by a distinctive “whooping” sound during inhalation.
“The public, especially pregnant people and those in close contact with infants, are encouraged to be aware of symptoms related to pertussis and to ensure vaccinations are up to date,” Newfoundland and Labrador’s Health Department said in a statement.
Whooping cough can be treated with antibiotics, but vaccination is the most effective way to control the spread of the disease. As a result, the province has expanded immunization efforts this school year. While booster doses are already offered in Grade 9, the vaccine is now being offered to Grade 8 students as well.
Public health officials say whooping cough is a cyclical disease that increases every two to five or six years.
Meanwhile, New Brunswick’s acting chief medical officer of health expects the current case count to get worse before tapering off.
A rise in whooping cough cases has also been reported in the United States and elsewhere. The Pan American Health Organization issued an alert in July encouraging countries to ramp up their surveillance and vaccination coverage.
This report by The Canadian Press was first published Sept. 10, 2024.
