Medical Bulletin 14/August/2025

Led by Dr. Sue D. Pedersen, MD, endocrinologist and obesity medicine specialist in Calgary, the guidelines highlight a patient-centered, individualized approach to obesity treatment.

“Obesity pharmacotherapy is a safe and effective option to support long-term obesity care,” says Dr. Pedersen. “It is one of three pillars of treatment outlined in the full Canadian Adult Obesity Clinical Practice Guideline, with other pillars being behavioural and psychological and surgical approaches. Obesity treatment should always be tailored to each person’s specific health needs, values, and preferences. Recommendations also support sustained use of obesity pharmacotherapy as part of a long-term strategy to maintain improvements in health and quality of life.”

Notably, the new recommendations include the use of tirzepatide and setmelanotide, and address the management of obesity-related complications such as atherosclerotic cardiovascular disease, heart failure with preserved ejection fraction, and osteoarthritis. The guideline also advises against compounded obesity medications due to concerns over their safety, efficacy, and content quality.

Despite advancements, access to obesity treatment remains limited. The panel highlights that only Alberta currently recognizes obesity as a chronic disease, and barriers like stigma, cost, and inadequate insurance coverage continue to hinder access.

These updates aim to guide healthcare professionals in providing more equitable, evidence-based care and to reinforce the role of pharmacotherapy in improving both short- and long-term health outcomes for patients with obesity.

Reference: Pharmacotherapy for obesity management in adults: 2025 clinical practice guideline update, Sue D. Pedersen, Priya Manjoo, Satya Dash, Akshay Jain, Nicole Pearce, Megha Poddar

CMAJ Aug 2025, 197 (27) E797-E809; DOI: 10.1503/cmaj.250502

Surgical Implant Slows Vision Loss in Rare Eye Disease: NEJM Evidence Study

In a new development for patients suffering from macular telangiectasia type 2 (MacTel), a rare and progressive retinal disease, a surgically implanted neuroprotective device has been shown to slow vision loss. The findings, published in NEJM Evidence, are based on two Phase III clinical trials evaluating the effectiveness of ENCELTO—a device that delivers a therapeutic protein directly to the retina to preserve central vision.

MacTel is a degenerative condition that gradually destroys central vision, severely impacting quality of life. Until now, there have been no approved treatment options for this orphan retinal disorder. The ENCELTO device offers a novel approach: it is surgically implanted and continuously releases ciliary neurotrophic factor (CNTF), a protein known to protect retinal neurons.

The two randomized trials enrolled 228 participants across 47 international sites and followed them over 24 months. The study showed that the implant could significantly slow photoreceptor cell degeneration compared to sham-treated eyes.

The ENCELTO implant consists of genetically modified retinal pigment epithelial cells housed within a tiny, collagen-based capsule. This design shields the cells from immune rejection while enabling the sustained release of CNTF directly to the retina.

In one trial, ENCELTO led to a 54.8% reduction in the rate of ellipsoid zone loss—a key structural indicator of photoreceptor degeneration. The second trial also demonstrated a significant reduction of 30.6%, supporting the treatment’s efficacy.

"This is a step toward redefining how we think about vision loss. Instead of waiting for cells to die, we're learning how to protect and preserve them," said Professor Martin Friedlander of Scripps Research, US. "This is the first time we've seen a therapy meaningfully alter the course of MacTel. It confirms that neuroprotection can be a powerful strategy to preserve vision in degenerative retinal conditions," he added.

The research underscores the potential of neuroprotective strategies in managing vision-threatening conditions.

Reference: https://www.nei.nih.gov/about/news-and-events/news/study-confirms-long-term-benefit-implant-blinding-eye-disease

IISc’s Magnetic Nanobots Offer Durable Relief from Tooth Sensitivity

In an advancement for dental care, scientists at the Indian Institute of Science (IISc), in collaboration with Bengaluru-based deep-tech startup Theranautilus, have engineered “CalBots” — tiny magnetic nanobots capable of offering long-lasting relief from tooth sensitivity with a single treatment. The findings of the study are published in Advanced Science.

Tooth sensitivity, which affects nearly one in four people globally, arises when microscopic tubules in the dentin — the layer beneath enamel — are exposed, allowing sensations such as cold or heat to reach nerve endings. While desensitizing toothpastes offer only surface-level relief and require repeated use, CalBots aim to tackle the root cause with lasting impact.

“We didn't want to create a slightly better version of what's already out there,” said Shanmukh Peddi, lead author and postdoctoral researcher at IISc’s Centre for Nano Science and Engineering (CeNSE), and co-founder of Theranautilus. “We wanted a technology that solves a real problem in a way that no one's attempted before.”

The CalBots, each about 400 nanometers in size, are coated with a proprietary calcium silicate-based bioceramic cement. When guided by an external magnetic field, they penetrate deep into the dentinal tubules—up to 300–500 micrometers—and form cement-like plugs that mimic natural tooth structure. In lab tests using extracted human teeth, the bots successfully sealed the exposed dentin in just 20 minutes.

The team then conducted animal trials, where mice with induced tooth sensitivity avoided cold water. After treatment with CalBots, they resumed drinking cold water, indicating “100% behavioral recovery,” Peddi said.

Composed entirely of GRAS (Generally Recognized As Safe) materials, CalBots passed toxicity tests in mice without adverse effects.

Reference: Shanmukh Peddi et al, Directed Self-Assembly of Magnetic Bioceramic Deep Inside Dentinal Tubules May Alleviate Dental Hypersensitivity, Advanced Science (2025). DOI: 10.1002/advs.202507664