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This article examines the development of antipsychotic medications in the period following the discovery of chlorpromazine in the mid-1950s up to the early 21st century. This era is defined by the identification of dopamine modulation as the central mechanism for treating psychosis, and by the development of a diversity of treatments around this mechanism. This strategy yielded a broad range of effective treatments and transformed clinical care; however, with the notable exception of clozapine, it failed to produce substantial gains in overall efficacy. Newer agents primarily differed in tolerability rather than therapeutic impact. Partial dopamine agonists refined, rather than replaced, this approach. As a result, the dopaminergic era offers a cautionary lesson for psychiatric drug development and underscores the need to move beyond dopamine-based models per se.
The recent introduction of the first non-dopaminergic antipsychotic marks a pivotal moment in psychopharmacology. This article revisits the development of chlorpromazine, the world’s first licensed antipsychotic, and considers what its history reveals about innovation in psychiatric drug discovery. Chlorpromazine emerged in the early 1950s as a treatment for surgical shock. Its subsequent recognition as an antipsychotic transformed psychiatric care, ushering in the modern era of psychopharmacology. This article argues that chlorpromazine’s success was not serendipitous: it depended on specific enabling conditions, including rigorous behavioural neuroscience, astute clinical observation across disciplines, close collaboration between clinicians and industry, and relatively agile regulatory frameworks. Understanding these factors is essential as psychiatry enters a new phase of drug development for the treatment of psychosis.
After more than seven decades in which antipsychotic drug development has been dominated by dopaminergic mechanisms, the recent emergence of a muscarinic receptor-based treatment represents a conceptual shift in the pharmacotherapy of psychosis. This article reviews the history and development of the first clinically effective non-dopaminergic antipsychotic, tracing its origins to unexpected behavioural effects observed during trials of muscarinic agonists developed for Alzheimer’s disease. Early studies of the muscarinic agonist xanomeline demonstrated antipsychotic efficacy, but were limited by poor tolerability due to peripheral cholinergic adverse effects. Subsequent progress depended on the dissociation of central therapeutic effects from peripheral side-effects, through the combination of xanomeline with the peripherally restricted muscarinic antagonist trospium. The development of this treatment highlights several broader lessons for psychiatric drug discovery, including the value of revisiting previously abandoned compounds, the benefits of leveraging existing human safety data on the importance of early-phase translational research and the role of innovative companies.
Alzheimer’s disease is a progressive and incurable condition and the leading cause of dementia worldwide. Lim et al’s (2024) Cochrane Review on the acetylcholinesterase inhibitor galantamine and its effects in Alzheimer’s disease and mild cognitive impairment (MCI) concluded that the drug slows cognitive and functional decline in Alzheimer’s disease, but not in MCI. However, in several studies the handling of data after drop-out was a potential source of bias. In this month’s Round the Corner, we also propose that the characteristics of the patient sample limit the external validity of the findings, and that the research question, although valid, is of limited practical importance.
Each study design has unique characteristics, strengths, and weaknesses. Study designs include descriptive (cross-sectional, case reports, case series), timed (prospective, retrospective, longitudinal), observational (case–control, cohort, non-concurrent cohort) and interventional (clinical trial). Which study design is chosen has an effect on how strong the resulting evidence will be.
This chapter explores research ethics, emphasising the principles and processes that safeguard participants and ensure integrity in health research. Foundational ethical principles, including respect for autonomy, beneficence, non-maleficence, and justice, are outlined, with reference to historical abuses that shaped modern ethical frameworks. The UK system for research governance is described, including the role of Research Ethics Committees (RECs), the Health Research Authority (HRA), and the Integrated Research Application System (IRAS). The process of ethical review, informed consent, data protection, and considerations for vulnerable populations are explained. Common challenges such as balancing risks and benefits, managing conflicts of interest, and ensuring transparency are discussed. The chapter highlights the ethical obligations of researchers throughout the study lifecycle, from protocol development to dissemination of results. Practical guidance is provided for preparing applications, engaging with RECs, and addressing feedback. By situating ethical principles within the regulatory framework, the chapter underscores the importance of embedding ethics into all stages of research. *This chapter maps to syllabus section 3.5
Social media offers research teams new opportunities for outreach and study recruitment; however, research teams often need guidance and tools on how to use social media to effectively recruit for their clinical trials. To address this gap, the Recruitment Innovation Center (RIC) developed a new, comprehensive toolkit informed by community feedback and extensive RIC experience. The toolkit contains guidance and considerations for using social media to recruit clinical trial participants, including best practices, platform-specific strategies, and customizable templates. This paper details the creation and contents of this new, free resource.
To evaluate the publication efficiency of registered cochlear implant (CI) trials and characterise evolving research trends following the 2022 update.
Methods
This study queried ClinicalTrials.gov to assess publication rates for trials completed before October 2022 and characterise research trends for subsequent registrations. Publication status was ascertained via PubMed and Google Scholar, and trial characteristics were analysed to identify predictors.
Results
Among 98 completed trials, only 26.5% were published. Publication was lowest for industry-sponsored (20.6%) and device trials (20.9%). Interventional design and larger enrolment showed positive but non-significant associations. Post-2022 registrations signalled diversification: device trials decreased (43.9% to 31.9%), while rehabilitation (13.3% to 20.3%) and procedural refinements (11.2% to 17.4%) expanded.
Conclusion
A marked gap persists in CI evidence dissemination, with only one-quarter of trials published. While device studies remain prominent, recent trends reflect a broadening research agenda with increasing emphasis on rehabilitation and surgical techniques, warranting continued monitoring.
Although randomised controlled trials (RCTs) have many merits and are suitable for interventions such as pharmaceuticals, there is a mismatch between RCTs and therapy. RCTs presuppose interventions that are standardised, specific, time-limited and measurable, characteristics that are less straightforward for therapy. Instead, a pluralistic evidence base is required for therapy.
People with schizophrenia spectrum disorders (SSDs) experience high rates of obesity and metabolic dysfunction, contributing substantially to excess morbidity and mortality. Glucagon-like peptide-1 receptor agonists (GLP-1 RAs) such as semaglutide and tirzepatide have demonstrated substantial efficacy for weight and glycaemic outcomes in the general population, but evidence in people with SSDs remains limited.
Aims
To synthesise all placebo-controlled, randomised controlled trials (RCTs) examining semaglutide and/or tirzepatide in people with SSDs.
Method
A preregistered systematic review and meta-analysis of RCTs examining the efficacy and safety of semaglutide and/or tirzepatide in adults with SSDs was conducted. Outcomes and adverse events were pooled using random-effects meta-analysis. Certainty of evidence was assessed using the GRADE criteria.
Results
Three trials (n = 258) met inclusion criteria, examining semaglutide dosages of 1.0–2.0 mg over 26–36 weeks. No trials examining tirzepatide were found. Semaglutide significantly reduced body weight (−11.32 kg; 95% CI −15.35 to −7.29), body mass index (−3.58 kg/m2; 95% CI −4.86 to −2.30), haemoglobin A1c (−0.37%; 95% CI −0.51 to −0.22) and fasting glucose (−0.54 mmol/L; 95% CI −0.94 to −0.13). In adverse event analyses, semaglutide was associated with increased risks of abdominal pain (risk ratio 2.93; 95% CI 1.13–7.60), vomiting (risk ratio 2.57; 95% CI 1.39–4.77) and constipation (risk ratio 3.23; 95% CI 1.14–9.18). There was no evidence of increased risk of serious adverse events.
Conclusions
Semaglutide produces clinically meaningful improvements in weight and glycaemic outcomes in people with SSDs, with an adverse event profile consistent with known gastrointestinal effects of GLP-1 RAs in the general population. These findings support semaglutide as a promising adjunctive metabolic intervention in this population, although larger and longer trials, specifically those testing tirzepatide, are needed to better characterise heterogeneity of effects and long-term safety of these promising pharmacological treatments.
Recruitment and retention challenges continue to hinder the success of clinical trials. Artificial intelligence (AI) has emerged as a promising means to optimize various clinical trial processes; however, its impact specifically on recruitment and retention has not been comprehensively evaluated. This scoping review utilized the Joanna Briggs Institute framework and adhered to PRISMA-ScR guidelines, systematically searching literature published between January 2018 and June 2024 across multiple databases. Of the 21,573 records screened, 121 studies were included. A meta-analysis was conducted to quantitatively assess the performance of AI-driven tools. AI applications for patient screening demonstrated strong performance, achieving a pooled sensitivity of 0.91 (95% CI: 0.84–0.95) and an area under the curve (AUC) of 0.79 (95% CI: 0.72–0.85). AI tools employed for eligibility identification and classification also exhibited strong outcomes, with pooled sensitivities of 0.80 (95% CI: 0.76–0.84) and 0.92 (95% CI: 0.84–0.96), respectively, and precisions of 0.84 (95% CI: 0.80–0.88) and 0.91 (95% CI: 0.85–0.95). AI tools aimed at identifying patient cohorts showed moderate effectiveness (pooled sensitivity: 0.70 [95% CI: 0.52–0.84]; AUC: 0.74 [95% CI: 0.61–0.84]). Overall, AI presents significant potential for enhancing clinical trial recruitment and retention, with effectiveness varying across specific applications. These findings underscore AI’s valuable role in improving trial efficiency and data quality.
An intricate landscape of bias permeates biomedical research. In this groundbreaking exploration the myriad sources of bias shaping research outcomes, from cognitive biases inherent in researchers to the selection of study subjects and data interpretation, are examined in detail. With a focus on randomized controlled trials, pharmacologic studies, genetic research, animal studies, and pandemic analyses, it illuminates how bias distorts the quest for scientific truth. Historical and contemporary examples vividly illustrate the impact of biases across research domains. Offering insights on recognizing and mitigating bias, this comprehensive work equips scientists and research teams with tools to navigate the complex terrain of biased research practices. A must-read for anyone seeking a deeper understanding of the critical role biases play in shaping the reliability and reproducibility of biomedical research.
This case report presents the case of a 25-year-old woman who developed ketamine addiction following a single sub-anaesthetic dose of intranasal ketamine in a pilot study investigating intranasal racemic ketamine for acute suicidality. She had a history of depression, obsessive–compulsive disorder, autism spectrum disorder and anorexia nervosa, and she had sporadically used alcohol and cannabis. Following the intervention, she reported a transient reduction in suicidal ideation but later sought illicit ketamine to recreate its calming effects on intrusive thoughts. Subsequently she also started abusing cocaine and 3-methylmethcathinone (3-MMC). Within weeks she had escalated to daily use, which led to financial distress, housing instability and a suicide attempt when access was cut off. Although she initially ceased use, she later relapsed into ketamine and cocaine addiction. This case highlights the addictive risk of ketamine, even in controlled settings. Given ketamine’s rising use in psychiatric treatment, careful screening, monitoring and awareness of addiction potential are essential. Future research should evaluate patient-specific risk factors and dosing strategies to minimise abuse liability.
People with intellectual disability experience substantial health inequities, including higher multimorbidity, increased healthcare utilisation and markedly reduced life expectancy. High-quality research is essential to address these disparities. The National Institute for Health and Care Research (NIHR) funded Research Delivery Network provides the infrastructure/expertise/support needed to deliver NIHR-funded studies, and supports studies funded by a non-commercial/industry partner. However, the effectiveness of NIHR-funded studies versus those supported in driving impactful intellectual disability research remains unclear.
Aims
To evaluate and compare the outcomes of NIHR-funded and supported intellectual disability research.
Method
All NIHR studies (funded/supported) relating to intellectual disability (2010–2020) were identified through systematic register searches. Primary outcomes included publication rates and impact on local, national and international clinical guidelines. Data collection was supplemented with a questionnaire to chief investigators and literature searches. Quantitative analyses examined associations between funding status, study design, publication and guideline impact, whereas qualitative responses explored implementation challenges.
Results
In total, 88 projects were identified, and 42% (37/88) were NIHR-funded. Overall, 81% of studies generated at least one publication and 28% informed clinical guidelines. NIHR funding was not significantly associated with publication or guideline impact. Randomised controlled trials (RCTs) were significantly more likely to be published and more likely to influence non-UK national and international guidelines than non-RCTs. The amount of funding showed no association with impact. Qualitative findings highlighted funding constraints, staff capacity and stakeholder engagement as key determinants of implementation.
Conclusions
NIHR-funded intellectual disability research was no more likely than NIHR-supported studies to result in publications or guideline impact.
It remains unclear whether the US clinical trial ecosystem is optimized to evaluate medical interventions efficiently. This study characterizes interventional clinical trials in the USA and examines trial progress over five years.
Methods:
Using the Aggregate Analysis of ClinicalTrials.gov (AACT) database, we conducted a cross-sectional study of interventional trials initiated in 2023 and a follow-up cohort tracking five-year completion for trials started in 2018 and registered in ClinicalTrials.gov as of 05/01/2024 by sponsor and therapeutic area. Trials with at least one US site were included. Primary outcomes were enrollment, completion status, intervention type, study arm design, and plan to share individual participant data.
Results:
Over 7,500 trials met inclusion criteria for each cohort. Most trials started in 2018 (68.4%) and 2023 (62.5%) enrolled fewer than 100 participants. Median enrollment in 2023 was higher for NIH (90) than industry-sponsored (76) trials. Within five years, 60.5% of the 2018 trials were completed, with higher completion among industry (60.9%) than NIH-sponsored (54.3%) trials. In 2023, industry predominantly funded cancer studies and trials testing drug interventions, whereas the NIH prioritized mental health studies and behavioral interventions. More than one-quarter of trials used a single-group design, 72.0% did not plan to share participant-level data, and 72.6% of drug trials were early phase.
Conclusion:
Many clinical trials are small, lack a control group, and are incomplete within five years, with differences by sponsor. Given the urgent need to improve health through rigorous evidence generation, there are likely opportunities to improve the US clinical trial ecosystem.