November 8, 2024

expert comments on the risks and benefits of tirzepatide following the death of Susan McGowan

Scientists comment on the risks and benefits of tirzepatide (Mounjaro) after a UK death linked to the drug.

Prof Naveed Sattar, Professor of Cardiometabolic Medicine/Honorary Consultant, University of Glasgow, said:

“The best quality evidence for the benefits and safety of medicines comes from randomised controlled trials conducted in a blinded fashion versus placebo in thousands of patients over a few years.  To date, data from around 10K people treated with tirzepatide in various trials in people living with diabetes or with obesity and risk factors, do not suggest a higher risk of pancreatitis.  Rather the data seem to show acceptable safety thus far, and a range of benefits including sizeable average weight loss (near 20%), strong diabetes prevention, and considerable benefits in people living with sleep apnoea, many of whom can stop their CPAP, and heart failure.  Further randomized trials with tirzepatide are ongoing in near 30 thousand patients which will report over the next 2-3 years are investigating effects on heart attacks, stroke, and kidney outcomes as well as all-cause mortality.  High quality trials are needed to give best evidence.  Single case reports cannot provide that evidence.  Given obesity is linked to many adverse events, many people stand to benefit from such medicines and as sad as this individual case is, it cannot on its own overturn the vast amount evidence that already exist.  Continued vigilance is needed of course, and authorities will continue to father all the evidence possible.”

Amanda Adler, Professor of Diabetic Medicine and Health Policy, Radcliffe Department of Medicine, University of Oxford said:

“Compared to new drugs in other disease areas, we know far more about these type of new drugs  – first marketed for type 2 diabetes, and now for overweight and obesity.  This is because the Food and Drug Administration in the US required very big studies.  These studies showed that the drugs were safe when used as in the studies. 

“Another drug which acts as a gut hormone, semaglutide (and specifically the formulation called Wegovy), has been shown to decrease the risk of having, or dying from, heart attacks and strokes compared to people who were allocated dummy drug in studies;  in the UK, in addition to the indications of type 2 diabetes and obesity, the drug now has a licence for cardiovascular risk prevention. 

“Susan McGowan’s death is sad indeed; whether or not it was related to tirzepatide may be difficult to prove. 

“Adverse reactions which the British regulators consider to be ‘very common’ include nausea, diarrhoea, vomiting, and constipation, and for people with type 2 diabetes on drugs called sulphonylurea or insulin, then low blood sugars.  Tirzepatide can be associated with ‘uncommon’ problems such as acute pancreatitis, but one can develop acute pancreatitis for many other reasons as well.

“This case highlights the importance of the ‘yellow card scheme’, run by the MHRA who has responsibility for the safety of medications.  Any member of the public or health profession can fill in a yellow card to list suspected side effects of drugs.”

Declared interests

Amanda Adler: I am an investigator on a Lilly-funded trial for a different drug.  I receive no money from this personally, nor does my unit.

Prof Naveed Sattar: “has consulted for several companies that make diabetes medicines but also contributed to several lifestyle trials.

For Novo Nordisk: have consulted for company in advisory boards but not on any of their weight loss drug trial committees; am on steering committee for ZEUS trial but this is not a weight loss trial product but anti-inflammatory.  Do not have any shares either for any product in health etc.

N.S. declares consulting fees and/or speaker honoraria from Abbott Laboratories, Afimmune, Amgen, AstraZeneca, Boehringer Ingelheim, Eli Lilly, Hanmi Pharmaceuticals, Janssen, Merck Sharp & Dohme, Novartis, Novo Nordisk, Pfizer, and Sanofi; and grant support paid to his university from AstraZeneca, Boehringer Ingelheim, Novartis, and Roche Diagnostics.”