Gayasha Natheegama Gamarachchige picture

Dr Gayasha Batheegama Gamarachchige


Postgraduate Research Student

Academic and research departments

School of Health Sciences.

About

My research project

Publications

Gayasha Somathilake, Christopher Wood, Colm Andrews, Jonathan J. Aning, Jo Armes, Elizabeth Ford, Robert Stephen Kerrison, Brian MacKenna, Amir Mehrkar, Mary Rehman6, Alex J. Walker, Agnieszka Lemanska (2026)Changing trends in androgen deprivation therapy prescribing for prostate cancer in England, 2015–2024, In: Journal of Oncology Pharmacy Practice Sage

Abstract IntroductionGonadotropin-releasing hormone (GnRH) agonists are the most commonly used form of androgen deprivation therapy (ADT) for advanced prostate cancer, often prescribed with radiotherapy or chemotherapy. This study examined national trends in the prescribing of injectable GnRH agonists in England from 2015 to 2024, by formulation type and demographic factors (age, ethnicity, and deprivation). We hypothesised that the use of longer-acting formulations has been increasing over time, specifically during the COVID-19 pandemic when access to face-to-face appointments was limited, and that variation over time and by demographics could inform future service delivery.MethodsWith the approval of NHS England, we conducted a cohort study using the OpenSAFELY-TPP database of 24 million adults. Monthly prescription counts and rates (per 100,000 men with prostate cancer) were visualised over time. Generalised linear models were used to estimate the impact of the COVID-19 pandemic.ResultsThe cohort included 390,265 men with prostate cancer (mean age 69.8 years, SD 13.5). Overall, 1,535,725 prescriptions were issued to 208,010 participants (53%). Monthly prescription counts increased by 40%, from 11,787 in 2015 to 16,697 in 2024, while rates declined from 8,453 to 7,721. During 2020–2021, prescribing of 1- and 3-monthly formulations decreased, whereas 6-monthly formulations increased from 437 per month (245 per 100,000 men) in 2019 to 755 (349 per 100,000 men) in 2024, an excess of 29%.ConclusionsBefore the pandemic, 6-monthly formulations were rarely prescribed. Their uptake during the pandemic suggested a shift towards longer-acting formulations, reducing treatment burden. Declining GnRH rates may reflect earlier diagnosis and evolving treatment guidelines. Divergence between prescription counts and rates, and variation by demographic factors, reflected challenges faced by healthcare systems.Keywords: androgen deprivation therapy, ADT, gonadotropin-releasing hormone agonist, GnRHa, luteinising hormone-releasing hormone agonist, LHRHa, prostate cancer, COVID-19, healthcare provision