Overcoming barriers to adherence through innovative injectable medications: A systematic review of therapeutic options for cardiovascular disease, reported adherence, and perspectives on their use

This review explored the development and use of injectable medications for cardiovascular disease (CVD), focusing on adherence and persistence rates, as well as barriers and facilitators to their use from the perspectives of patients and healthcare professionals. A systematic search was conducted across Web of Science, Academic Search Complete, CINAHL, PubMed and Medline for English-language studies published between January 2005 and March 2025. Eligible studies included those examining injectable CVD therapies which reported on adherence and persistence metrics, and stakeholder perspectives on their use. A total of 54 studies were included. Reported adherence and persistence rates varied widely across therapies, with PCSK9 inhibitors (typically administered once every 2-4 weeks) and once-weekly GLP-1 receptor agonists generally associated with higher persistence compared to daily injectable regimens. Key barriers included injection-related discomfort, needle anxiety, side effects, cost and limited knowledge of healthcare professionals (i.e. physicians). Patients have highlighted emotional and physical concerns, while healthcare professionals emphasized the need for education and support. Injectable therapies may improve cardiovascular risk management, and are often dosed less frequently than oral formulations, offering advantages in terms of adherence. However, challenges remain. Addressing both psychological and structural barriers through enhancing healthcare professionals training, patient education and system-level support may help improve adherence rates and improve long-term outcomes.