Comparison of Two Financial Incentives to Encourage the Use of Adalimumab Biosimilars: Results of a French Experiment Close to Clinicians.

Background: In 2018, the French government introduced two mutually exclusive financial incentives to increase etanercept and insulin glargine biosimilar use. The general case redirects 20% of the price difference between the reference product and its biosimilars to hospitals for every biosimilar dispensed in community pharmacies from hospital prescriptions. The experimental case redirects 30% to prescribing clinical units after hospital selection. Adalimumab was added to these incentives in 2019, after its first biosimilar was launched.

Objective: This retrospective observational study aimed to compare both general and experimental incentives after 19 months to assess the impact of directly incentivizing clinical units for adalimumab biosimilars.

Method: The monthly number of adalimumab boxes dispensed in community pharmacies was linked to the corresponding hospital's prescription using IQVIA Xponent data from November 2017 to October 2020. The monthly mean rate of adalimumab biosimilars was compared between incentive groups and subgroups depending on hospitals' prior experience with the etanercept experimental case.

Results: General case hospitals had a significantly lower mean biosimilar uptake (16.7% vs 23.2%, p = 0.029) than those included in the experimental case. Twenty-three of the 40 hospitals in the experimental case and ten out of the 91 hospitals studied in the general case had already taken part in the etanercept experiment. Biosimilar uptake was higher, but not statistically significant, for hospitals with prior experience in the adalimumab general case group (p = 0.086).

Conclusions: This study confirmed that incentivizing close to physicians was more effective in increasing the biosimilar rate. It also suggested that previous incentive experience positively influenced biosimilar penetration.