NOR-SWITCH Study Validates Biosimilar Use in Multiple Indications Save

Lancet reports the results of the NOR-SWITCH study - a trial performed in Norway as biosimilars were being introduced. This study was designed to assess the efficacy and safety of transitioning from the originator (Remicade) to the less expensive biosimilar CT-P13 (Remsima/Inflectra) in the treatment of Crohn's disease, ulcerative colitis, spondyloarthritis, rheumatoid arthritis, psoriatic arthritis, and chronic plaque psoriasis.

NOR-SWITCH was a phase IV, 52 week, randomised, non-inferiority, double-blind trial with 52 weeks where 482 patients (previously on stable regimen of infliximab originator) randomised 1:1 to either continued infliximab originator or to CT-P13 treatment, with unchanged dosing regimen. The primary endpoint was disease worsening (according to different disease activity measures for each inflammatory condition) falling outside of the non-inferiority margin of 15%.

Most of the patients in the analysis set had Crohn's disease (32%), with fewer havng ulcerative colitis (19%), spondylitis (19%), RA (16%), PsA (6%) or psoriasis (7%).

Disease worsening occurred in 26% of the originator group and 30% of the biosimilar (CT-P13) group - thereby meeting the definition of noninferiority at 52 weeks. While the differences between drugs for those with Crohn's disease appeared to be near significant, they were not. Moreover, this trial was powered to assess noninferiority for all conditions combined and not individual disorders.Adverse events was similar between groups, including adverse events leading to discontinuation (4% vs. 3%).

The NOR-SWITCH trial will be one of the most cited trials as biosimilars are introduced in the US and worldwide. The data suggests that analytical proof of biosimilarity appears to be extrapolatable to the clinical indications afforded new biosimilars.

This trial is registered with ClinicalTrials.gov, number NCT02148640.