The Medicines and Healthcare products Regulatory Agency (MHRA) has published Drug Safety Update for March 2025 (PDF).
This issue advises healthcare professionals that indication for the treatment of post-operative pain has been removed from the licences of all prolonged release opioids due to the increased risk of persistent post-operative opioid use (PPOU) and opioid-induced ventilatory impairment (OIVI). Hospitals are recommended to explain the risks before operative procedures. At discharge, a pain management plan should be shared with the primary care and the patient should be provided with an adequate supply of immediate-release opioids to treat acute post-operative pain to minimise the risk of PPOU, dependence, stock piling of unused opioids and potential for diversion. Primary care clinicians should be vigilant for post-operative opioid use and ensure that pain management plans are reviewed and implemented accordingly including the plan for end of treatment.
Action: Clinicians should be aware of this month's new guidance and implement any necessary changes to practice.
The New England Journal of Medicine has recently published the results of a long term study investigating the safety and efficacy of tirzepatide in reducing weight and delaying progression to type 2 diabetes.
The study recruited 2,539 participants with obesity, of whom 1,032 also had prediabetes. The study had four arms, tirzepatide at 5 mg, 10 mg, or 15 mg and placebo. Follow up was planned for 3 years. The last on-treatment review was performed at 176 weeks with an additional follow up after 17 weeks off treatment. At 176 weeks, the three treatment arms produced statistically significant weight loss of between 15.4% and 22.9% depending on the dose. (Table S4) And fewer participants in the treatment group received a diagnosis of type 2 diabetes.
The study concluded that tirzepatide treatment demonstrated a "substantial and sustained weight reduction and a markedly lower risk of progression to type 2 diabetes".
After the 17 week off-treatment phase, overall weight loss was reported to be between 12.3% and 17.9% (Table S5). Approximately 20% of the weight lost during the treatment phase had been regained. The confidence intervals (Fig 1B) for the data points at week 193 are discrete for each tirzepatide strength from the 176 week data point, indicating that the weight gain off treatment is statistically significant.
Weight gain after stopping weight loss treatments has been demonstrated for previous treatments including orlistat, sibutramine (withdrawn in 2010 over cardiovascular safety concerns), rimonabant (withdrawn in 2008 due to concerns over psychiatric side effects) and semaglutide.
Action: Clinicians will be aware that sustained weight loss requires long term lifestyle modification, including a calorie controlled diet and increased physical activity. The results of this study are not surprising; the weight gain observed during the off-treatment phase highlights how crucial it is for lifestyle changes to be maintained.
During February 2025 Clinical Knowledge Summaries were published or updated in the following areas.
The Hypokalaemia topic is new. All of the other topics have been reviewed and updated with minor structural and layout changes. The Hypertension in pregnancy topic has been updated with a recommendation to provide reassurance where inadvertent exposure to an ACEi or ARB has occurred; this is due to the lack strong evidence that use in the first trimester poses a teratogenic risk to the foetus. Recommendations for culture and sensitivity testing for women with asymptomatic bacteriuria were aligned with the latest guidance from NHS England. The Obesity topic has been updated in line with the new NICE Overweight and obesity management guideline.
Action: Clinicians who see patients with any of these conditions may find the new and updated information useful when reviewing current clinical practice.
The Medicines and Healthcare products Regulatory Agency (MHRA) has published Drug Safety Update for February 2025 (PDF).
This issue advises healthcare professionals that review by two specialists remains in place for patients initiating valproate under 55 years of age but the Commission on Human Medicines (CHM) has advised that it will not be required for men (or males) currently taking valproate. To aid the decision making process for initiation and review, three infographics have been produced, for female patients under 55 years old, for male patients under 55 years old and for male and female patients 55 years and older. Patients are recommended to continue taking valproate until reviewed by their specialist.
Lastly, this issue contains a summary of letters to healthcare professionals in January. These generally related to supply issues and recalls.
Action: Clinicians should be aware of this month's new guidance and implement any necessary changes to practice.
The National Institute for Health and Care Excellence (NICE) have published new or updated guidance for the month of February 2025. This month there is one guideline that impacts upon primary care.
The Tobacco: preventing uptake, promoting quitting and treating dependence guideline has been updated. It covers support to stop smoking for everyone aged 12 and over, and help to reduce people's harm from smoking if they are not ready to stop in one go. It also covers ways to prevent children, young people and young adults aged 24 and under from taking up smoking. This update reviewed the evidence for cytisinicline (sometimes referred to as cytisine) and made new and updated recommendations in the section on stop-smoking interventions.
Action: Clinicians should be aware of this month's new guidance and implement any necessary changes to practice.
