Background The biosimilar medicines are identical to authorised biological medicines. The biosimilar infliximab, a TNF-α inhibitor, was approved by the EMA for use in rheumatoid arthritis, ankylosing spondylitis, Crohn’s disease, ulcerative colitis, psoriatic arthritis and psoriasis. Studies have shown that the biosimilar of infliximab demonstrates pharmacokinetics and therapeutic equivalence relative to its reference, with lower costs, making it a useful alternative in terms of cost-efficacy. Portugal was the first EU country that authorised the the use of biosimilar monoclonal antibodies.

Purpose To analyse the efficacy and cost of treatment with the biosimilar infliximab in comparison with its reference.

Material and methods All new patients treated with infliximab between January 2014 and July 2015 were considered for our study. The criteria used to evaluate treatment efficacy were: for psoriatic and rheumatoid arthritis, the number of tender joints and the number of swollen joints; for ankylosing spondylitis, the BASDAI and BASFI scales; for patients with Crohn’s disease and ulcerative colitis, biochemical and clinical development before and after treatment with infliximab.

Results Our sample comprised 46 patients, 23 treated with the biological reference and 23 with the biosimilar. According to the medical records, there was similar efficacy between the reference and the biosimilar infliximab. 73.9% (17/23 in both arms) of treated patients were responders. 21.3% (5/23) of patients treated with the reference infliximab and 13.0% (3/23) in the biosimilar group stopped treatment because of inefficacy. One patient in the biosimilar treatment group stopped because of toxicity. The economic impact of switching all patients to a biosimilar could result in a 30% saving in annual spending on infliximab, corresponding to 200 000€ (for actual prices).

Conclusion The use and monitoring of biosimilars in hospitals, and their proven efficiency and safety compared with the reference, has opened the discussion on the therapeutic change (switch) between biopharmaceuticals and their biosimilars. The savings associated with the use of biosimilars contributes to the sustainability of the health system, relieving resources so that patients continue to take advantage of therapeutic innovation in Portugal.

References and/or Acknowledgements

1. McKeage K. Biodrugs 2014;28:313-21

2. What you need to know about biosimilar medical products, European Commission

References and/or AcknowledgementsNo conflict of interest.