Biologics prescription for chronic inflammatory rheumatic diseases in Tunisia.

Aims: To analyse the prescription of biologics (bDMARDs) in chronic inflammatory rheumatic diseases (CIRD) from Tunisian National Health Insurance (CNAM) data and to estimate their direct costs and associated factors.

Methods: One hundred and nine consecutive patients who received at least one bDMARDs during a six-month period from January to June 2022 were analysed. Clinical and therapeutic parameters as well as data related to the choice of bDMARDs were identified. Direct costs were assessed. Excess costs were considered if the monthly costs exceeded 2200 Tunisian dinars (TD) per patient.

Results: The most common CIRD was axial spondylarthritis (AS) in 44% and rheumatoid arthritis (RA) in 37.6% of cases. Juvenile idiopathic arthritis represented 2.7% of cases. In Tunisia, prescribing of bDMARDs is concentrated in the coastal regions and follows the distribution of rheumatologists. Certolizumab pegol was the most prescribed agent in 45% of cases. No significant association was found between the choice of bDMARD and the characteristics of patients, CIRD or prescribers. The total monthly cost of bDMARDs was 225,535 ± 1269 TD. Overspending was significantly associated with initial high DAS28 in RA and young age and total hip replacement in AS.

Conclusion: Prescription of bDMARDs in CIRD is mainly for AS and in the coastal regions of Tunisia. The burden is considerable, partly due to the high cost of biologics. Data from this study may enable public health managers to better allocate the limited resources available for patient care and to develop medico-economic strategies to reduce health care costs.