Researchers at McMaster University are developing a pair of rapid diagnostic tools that could slash wait-times for critical drug-monitoring results, allowing clinicians to personalize treatments for mental health conditions in real-time.
With psychotropic medications, which are prescribed for many mental health disorders, the line between therapy and toxicity is vanishingly thin. Too small a dose, and the medication will have no effect. Too much, and the same drug can trigger dangerous side effects.
The challenge for prescribers is that there is no one-size-fits-all solution for these drugs. Age, genetics, metabolism, diet, and other medications can all change where the line between therapy and toxicity sits, making each individual patient a unique case.
In recent years, clinicians have eliminated much of the guesswork from dosing through an advanced laboratory technique called therapeutic drug monitoring (TDM). TDM allows for clinicians to more precisely tailor a drug’s dosage to a specific patient’s needs by monitoring exactly how much of the drug is circulating in their bloodstream, and adjusting dosage accordingly.
But TDM takes time — often up to 15 days for results to arrive from specialized laboratories.
“For patients, these delays can feel like an eternity,” says Leyla Soleymani, a professor of engineering physics at McMaster University. “Enduring weeks of ineffective treatment or serious side-effects is not only difficult for patients, but it can quickly shake their trust in health care and leave them even more vulnerable to the impacts of mental health disorders.”
That’s why Soleymani’s group is aiming to shrink TDM’s 15-day wait time down to just 10 short minutes.
With $1.2 million in new funding from the Natural Sciences and Engineering Research Council of Canada (NSERC), her team is developing the world’s first rapid, point-of-care diagnostics for TDM of psychotropic drugs: a handheld finger-prick blood test and a wearable device that uses microneedle tech for real-time drug monitoring.
Both devices are being designed to deliver lab-accurate results in the span of a single doctor’s appointment.
Karin Neufeld, chair of the Department of Psychiatry and Behavioural Neurosciences at McMaster and a collaborator on the project, says that the rising burden of mental health disorders is creating an urgent need for faster, more accessible approaches to TDM.
“Mental health disorders are very prevalent and there is a significant need for timely therapeutic drug monitoring strategies,” says Neufeld, who is also a psychiatrist at St. Joseph’s Healthcare Hamilton’s community psychiatry clinic. “These new technologies have the potential to transform drug monitoring in mental health, expand access in remote settings, and enable timely, personalized care with meaningful impact for patients and healthcare systems.”
The new wearable tech uses pain-free microneedle patches to detect drug volumes in the blood and interstitial fluid.
Both the finger-prick test and the wearable device will be powered by new aptamers — tiny strands of DNA that are engineered to recognize specific molecules. Researchers will integrate these aptamers into the devices’ electronic chips, which generate electrical signals when they detect traces of specific drugs within the bloodstream or the skin interstitial fluid. The data is then beamed to a nearby smartphone for almost instantaneous results.
Soleymani, who leads engineering innovation for NexusHealth at McMaster, notes that the development of these new diagnostics has been informed by personal discussions with patients, their families, and their care providers.
“Initially, we intended to develop a minute-by-minute, at-home monitoring device, but we heard directly from patients and clinicians that it didn’t resonate with them,” says Soleymani, who is also an associate member of McMaster’s Department of Biochemistry and Biomedical Sciences and School of Biomedical Engineering. “We heard about their wants and needs, and those of their care providers, and we changed course completely.”
These critical co-design consultations, brokered by the Research Institute at St. Joseph’s Health System, provided the research team with fundamental insights about product design. For example, determining where patients would use the devices changed their architecture, and understanding how frequently the devices would be used changed the chemistry involved.
“Patient voices and lived experience have helped shape this work from its earliest stages,” says Sarah Howe, chief operating officer at the Research Institute at St. Joseph’s Health System. “Building new technologies hand-in-hand with the patients, families, and clinicians who will use them is the definition of compassionate innovation.”
Soleymani’s team is now working closely on the development of these new diagnostics with Mahla Poudineh and Juewen Liu, both researchers at the University of Waterloo. Poudineh, an expert in wearable biosensing technologies for therapeutic and diagnostic applications, and Liu, a leader in DNA aptamer research, are both longtime collaborators of the McMaster team.
“This project comes after years of collaborative research between our groups,” says Poudineh, an associate professor of electrical and computer engineering. “By combining the McMaster team’s expertise in DNA sensors with Waterloo’s expertise in microneedle technologies and aptamers, we’re now working toward the development of new wearable diagnostics that could make TDM faster and more accessible for patients.”
“Our history of collaboration on aptamer-based biosensors positions this project for success,” adds Liu, a professor of chemistry. “Already, we have worked together on similar diagnostics for lactate monitoring, giving us a strong foundation to build from.”
As the new devices take shape, the research team will collaborate with experts at LifeLabs to bring this innovative technology into the hands of the healthcare teams and patients that need it most. That partnership is critical, Soleymani says, because LifeLabs has the infrastructure and expertise to support both the de-risking and validation needed to bring the new diagnostics into clinical practice.
Catherine Ross, vice-president of medical and quality affairs at LifeLabs, says the development of rapid, painless, and practical devices like these align well with LifeLabs’ commitment to delivering patient-centred solutions that elevate quality of care across the country.
“We have a responsibility to continually raise the bar for patient care,” says Ross. “That means making laboratory services that empower healthier Canadians while maintaining the highest standards of quality and clinical excellence.”
Soleymani anticipates that the new technologies will be prototyped and ready for clinical validation within four years.