Switching patients with IBD from intravenous to subcutaneous biologics might improve convenience for patients but results in a financial loss to health services.

The findings have prompted the Melbourne gastroenterologists behind the economic analysis to call for alternative models of funding that reduce reliance on intravenous biologic-generated income in IBD care and incentivise a switch.

Their retrospective analysis involved 344 patients who received intravenous infliximab or vedolizumab in the outpatient infusion centre of a tertiary IBD centre between July 2019 and June 2021.

Of the cohort (55% male, median age 37 for infliximab and 45 for vedolizumab), just over half had Crohn’s disease (54%) and the rest had ulcerative colitis (46%).

Data were collated from patients’ electronic medical records, pharmacy dispensing systems and the hospital business intelligence unit, while the financial impact was estimated under two additional scenarios using a random 10% and 30% of the cohort.

This accounted for the fact that an entire cohort switch would not be representative of real practice, said the researchers from the Austin Hospital and the Austin Academic Centre at the University of Melbourne.

Findings published in Internal Medicine Journal [link here] suggested that transitioning patients from intravenous to subcutaneous administration would result in a total loss of $2,732,123.75 (AUD) over two years to the health service.

This included $1,463,003.75 (AUD) in Weighted Inlier Equivalent Separation (WIES) – a funding model state governments use to pay hospitals based on the associated costs of treating patients – and $1,269,120 (AUD) in drug procurement revenue.

However, they also found a transition away from intravenous formulations would substantially ease capacity in the infusion centre by about 5256 hours of chair time, improving access to care for patients most in need of chair time.

“Loss of income appears to be substantial even when only 10% (AU$280,827.32) or 30% (AU $872,109.95) of the cohort is switched to subcutaneous administration with income generated from dispensing of subcutaneous drugs negligible in comparison,” the authors wrote.

“Given the lack of control by individual services to reallocate potential savings associated with a switch to subcutaneous administration, there is currently insufficient incentive for services to switch their patients, given the potential loss of revenue that may impact service provision unless there are significant changes to current funding models of IBD care.

“This further demonstrates the growing need for changes in how chronic diseases are funded in Australia.”