Obesity care gets personalised: tailoring therapies with Phenomix

Obesity treatment is undergoing a major shift, much like the advances seen in cancer care. Phenomix Sciences, led by CEO Mark Bagnall, is using precision medicine to make treatments more targeted and effective. In this interview, Bagnall explains how this approach is improving patient outcomes and driving the development of better obesity drugs.

A personalised approach to obesity treatment

Traditional obesity treatments have often followed a one-size-fits-all model, despite mounting evidence that obesity is not a singular disease but rather a collection of subtypes. Phenomix Sciences, built on over a decade of clinical research at the Mayo Clinic, is disrupting this outdated approach.

“The research demonstrated that obesity is not one disease, but many; each of which should be treated with different interventions,” says Bagnall.

To address this complexity, Phenomix developed the MyPhenome™ test, a saliva-based genetic test that identifies a patient’s specific obesity phenotype. This test provides critical insights into how a patient will respond to different treatment options, including medications, devices, bariatric surgery or lifestyle interventions.

“Knowing a patient’s subtype or phenotype can be used to guide obesity treatments of all kinds, including drug therapy, devices, bariatric surgery and even diet and lifestyle interventions,” Bagnall explains.

The MyPhenome test has already gained traction among obesity specialists, particularly in Chicago and Florida, and Phenomix has formed strategic partnerships with multiple pharmaceutical companies to support clinical trials and further analyse obesity-related data.

Lessons from oncology: precision medicine in action

The concept of precision medicine is not new – oncology has long relied on biomarkers to align patients with the most effective treatments. Advances in targeted therapies have significantly improved outcomes for cancer patients, and Phenomix aims to bring a similar level of precision to obesity care.

Much like cancer treatment, where some patients respond well to targeted therapies while others see little effect, obesity drugs also produce varied results. GLP-1 receptor agonists, such as Ozempic and Wegovy, have been hailed as game-changers in obesity care, but their effectiveness differs from person to person.

GLP-1 receptor agonists are a class of medications that mimic glucagon-like peptide-1 (GLP-1), a hormone that helps regulate blood sugar and appetite. These drugs slow digestion, reduce hunger and promote feelings of fullness, making them effective for both type 2 diabetes and weight loss.

This variability in patient response is referred to in oncology as the “Waterfall Plot Problem” – a phenomenon where some patients experience profound benefits from a therapy while others do not respond at all.

“Obesity specialists will tell you that their experience with GLP-1 medications follows the rule of ‘one-thirds’: one third of the patients will do really well, one third will experience good but not spectacular weight loss and one third will not benefit at all,” Bagnall notes.

By identifying which patients are most likely to benefit from GLP-1 drugs, Phenomix aims to streamline treatment selection, reducing the costly trial-and-error approach that currently dominates obesity care.

Obesity is rising worldwide, driven by lifestyle, diet, and genetics. This growing health challenge increases the risk of diabetes, heart disease, and other conditions.

The importance of patient stratification

Understanding the biological root causes of obesity is essential to improving treatment outcomes. Phenomix’s research has identified multiple obesity subtypes, including:

• Hungry Gut: patients whose stomachs empty too quickly, leading to excessive eating. These individuals respond four times better to GLP-1 medications.
• Hungry Brain: patients whose hunger signals are brain-driven, making GLP-1s less effective. These individuals may benefit more from alternative treatments such as Qysmia and/or bariatric surgeries.
• Emotional Hunger: patients who struggle with cravings and emotional eating patterns, requiring different pharmacological and psychological support. These individuals may benefit more from alternative treatments, such as Contrave or behavioural interventions.

By matching the right patient to the right treatment, Phenomix is dramatically increasing the success rates of obesity interventions. “Without understanding these differences, treatment becomes costly and a game of trial and error,” Bagnall points out.

Advancing drug development

The implications of precision medicine in obesity care extend beyond selecting the right treatment for individual patients; it is also reshaping the development of next-generation obesity drugs.

“In pharma, we’re supporting research into the development of more effective obesity drugs and leveraging our comprehensive data for improved clinical trial design and outcomes,” says Bagnall.

By integrating phenotyping into clinical trials, pharmaceutical companies can:

1. Improve drug efficacy by testing new treatments on the most responsive patient populations
2. Reduce trial failures by pre-selecting candidates who are likely to benefit
3. Optimise dosing strategies to minimise side effects and maximise effectiveness.

This level of data-driven precision is critical, especially as the demand for obesity treatments rises. With the growing acceptance of GLP-1 medications and the trend towards more convenient oral formulations, refining patient selection will be key to ensuring these drugs reach the right individuals while controlling healthcare costs.

The future of obesity treatment

Bagnall envisions a future where phenotyping becomes standard practice in obesity care, much like biomarker-driven treatment is in oncology.

“Phenotyping is still in its early stages, and we believe hundreds of additional obesity subtypes are yet to be identified,” he explains.

Currently, the MyPhenome test identifies three major subtypes highlighted above, Hungry Gut, Hungry Brain and Emotional Hunger. However, Phenomix is actively expanding its research to include additional categories, such as Slow Burn, which could provide new insights into metabolic variations.

Beyond refining treatment options, phenotyping could also play a major role in predicting obesity-related diseases such as diabetes, heart disease and certain cancers. By identifying patients at higher risk for these conditions, healthcare providers could implement preventative measures tailored to an individual’s unique biology. Phenomix is also working closely with insurance providers and healthcare systems to ensure obesity phenotyping is integrated into coverage policies. This would allow insurers to better allocate resources, ensuring that high-cost medications like GLP-1s are prescribed only to patients who will truly benefit.

Advances in genomics, biotechnology and AI-driven data analysis are driving a new era of personalised medicine, and obesity treatment is set to follow. With Phenomix Sciences leading the way, the trial-and-error approach to obesity care could soon become a thing of the past. As Bagnall puts it: “The future of obesity treatment will be personalised, just like oncology has become.”