Research review: a look at the latest clinical papers

In this monthly round-up, we review the latest clinical research from high-impact medical journals and draw out the findings most relevant to primary care and community pharmacy. Cahal McQuillan reports.

Endometriosis increases breast and ovarian cancer risk

People with endometriosis or adenomyosis have a higher risk of developing gynaecological and breast cancers for more than a decade after diagnosis, a Swedish study has found.

The nationwide cohort study, published in Acta Obstetricia et Gynecologica Scandinavica, used data belonging to almost 50,000 women diagnosed with endometriosis or adenomyosis between 1997 and 2018, and compared cancer incidence against the broader female population.

Although previous research had already established that people with an endometriosis or adenomyosis diagnosis were at an elevated risk of certain cancers, this paper clearly separated same-year diagnoses from subsequent-year diagnoses.

Related Article: Interview: closing the 9-year gap in endometriosis diagnosis

Ultimately, the study found that, for most cancers, the increased risks were confined to the same calendar year as endometriosis or adenomyosis diagnosis, with the authors highlighting the possible role of concurrent detection – cases identified through investigations prompted by suspicion of one condition leading to discovery of the other.

Nevertheless, a slightly elevated risk of developing ovarian and breast cancers persisted for more than a decade in individuals with endometriosis or adenomyosis. The researchers, therefore, emphasise that clinicians should have a higher index of suspicion for gynaecological or breast cancers in this demographic.

Vaping linked to more smoking relapses than other cessation methods

People who use vapes or e-cigarettes for smoking cessation have a higher risk of relapsing than those who use other nicotine replacement therapies (NRTs), a new study has found.

The study, led by researchers in the USA and published in BMJ Open, used data from more than 4,000 individuals to assess the relapse rates of people who were smoking or had quit smoking in 2015, but later switched exclusively to vapes or NRT.

The researchers found that among those who had quit smoking by 2015, users who had switched to vapes were roughly three times more likely to have relapsed to cigarette smoking by 2018 than NRT users.

The authors suggest that the physical and sensory similarities of e-cigarettes and cigarettes, as well as nicotine dosage, may make relapse more likely than with NRTs but call for further research into this.

Semaglutide and Alzheimer’s disease progression

Despite a growing body of observational evidence from animal, clinical, and real-world studies, oral semaglutide was found to be ineffective at slowing the progression of Alzheimer's disease in two phase 3, randomised, placebo-controlled trials.

The study, which included nearly 10,000 individuals with early-stage Alzheimer's disease across 40 countries, investigated whether 14 mg semaglutide taken once daily for three years could slow disease progression.

Related Article: Cochrane review finds anti-amyloid Alzheimer’s drugs show no 'clinically meaningful effect'

While the treatment significantly reduced several clinical biomarkers associated with Alzheimer's disease, neuroinflammation, neurodegeneration, and synaptic function, it did not slow clinical decline in patients.

The authors of the Lancet study, which was funded by Novo Nordisk, suggested the disconnect between their results and observational evidence possibly lay in the fact that trial participants were already symptomatic when the study began.

They, therefore, recommend that future trials investigate earlier-stage, asymptomatic populations, suggesting any protective effect of GLP-1 agonists may operate in a prevention window rather than a treatment window.

Phase 3 trial for new Tourette syndrome drug

Ecopipam maintained a clinically meaningful reduction in Tourette syndrome symptoms for up to 24 weeks in younger patients, a new phase 3 trial has found.

The study, published in JAMA Neurology, included 216 individuals – 167 children and 49 adults – with Tourette syndrome across 12 countries. Participants were randomised to receive either a target dose of 1.8 mg/kg of ecopipam or placebo daily for 12 weeks.

The researchers found that paediatric patients receiving ecopipam had a 53% lower risk of tic relapse than those receiving a placebo. Furthermore, while the trial was not designed to test efficacy in adults, study data support future investigations in this cohort.

Related Article: Experimental drug functionally cures hepatitis B for one-in-five people

Adverse events from ecopipam were mostly mild-to-moderate and primarily linked to the central nervous system. The most frequent side-effects were excessive drowsiness, anxiety, headache, and insomnia.

Crucially, ecopipam was not associated with any of the weight gain or movement disorders caused by existing Tourette syndrome medicines that target dopamine D2 receptors, which have often resulted in treatment cessation.

Ecopipam is the first drug for Tourette syndrome to target the D1 receptor, and these findings suggest it might offer an effective long-term treatment for tic suppression, particularly for younger patients.