For the tens of millions of people with type 2 diabetes managed on basal insulin, the question of whether continuous glucose monitoring offers meaningful advantages over traditional finger-stick testing has remained frustratingly unresolved — particularly as newer drug classes like GLP-1 receptor agonists and SGLT2 inhibitors have reshaped standard care. The FreeDM2 trial offers some of the most rigorous evidence yet on this question, with direct implications for how glucose monitoring technology should be allocated and prescribed.
The FreeDM2 trial enrolled adults with type 2 diabetes across 24 UK primary and secondary care centres. Eligible participants were managed on basal insulin alongside SGLT2 inhibitors, GLP-1 receptor agonists, or dual GIP/GLP-1 receptor agonists, with baseline HbA1c between 7.5% and 11.0%. Using a 2:1 randomisation, participants were assigned to real-time continuous glucose monitoring (CGM) or continued self-monitoring of blood glucose (SMBG). The trial ran in two phases: a 16-week self-management period with basal insulin self-titration, followed by a 16-week clinician-supported phase in which additional therapies could be initiated per national guidance. The primary endpoint was the between-group difference in HbA1c at 16 weeks.
This is a notable addition to the CGM literature because prior pivotal CGM trials — most prominently the DIAMOND and GOLD studies — focused on individuals using multiple daily injections of insulin, a population with arguably greater need for granular glucose data. The FreeDM2 population, using basal-only insulin alongside agents that themselves carry low hypoglycaemia risk, represents a much broader and more heterogeneous real-world group. Demonstrating superiority over SMBG in this context, if confirmed in the full results, would substantially expand the evidence base for CGM reimbursement decisions. Key limitations include the open-label design — inevitable given the nature of the intervention — and the relatively short 32-week follow-up, which may not capture durability of glycaemic benefit or long-term complication endpoints. Whether improvements in HbA1c translate to reduced microvascular or cardiovascular events over years remains an open question. Overall, this is a well-powered, clinically relevant superiority trial that could be incrementally paradigm-shifting for primary care diabetes management.