Results of the NOR-SWITCH study – a clinical trial performed in Norway was designed to assess the effectiveness and safety of transitioning from the originator medication Remicade (infliximab) to the less expensive biosimilar medication (Remsima/Inflectra) in the treatment of Crohn's disease, ulcerative colitis, spondyloarthritis, rheumatoid arthritis, psoriatic arthritis, and chronic plaque psoriasis.
What are Biosimilars?
A new class of drugs called biosimilars is becoming increasingly available to consumers. Though these medications are very similar to already available drugs known as biologics, biosimilars are just now beginning to receive approval from the U.S. FDA.
To understand biosimilars and how they work, it’s important to first understand their predecessors, biologics. These drugs are approved by the FDA and used in treatment of a wide range of conditions and illnesses, from rheumatoid arthritis and inflammatory bowel disease to various forms of cancer as well as allergy shots and vaccines. Biologics are made from living organisms, including human sources, animals, bacteria, and yeast. Their makeup is incredibly complex, as is their development process.
A drug qualifies as a biosimilar if it is very similar to a FDA-approved biologic—similar in how it’s composed, how it works, and its safety. The preceding biologic drug is often called a reference medicine.
Biosimilars are different from generic medicines. Whereas generics and the original (trademarked) drug have identical active ingredients, such exact replication isn’t possible due to the complexity of biologics. As a result, biosimilars are similar to the reference medicine, but not identical. They must have very similar treatment outcomes and safety profiles to the biologic.
The aim of approving biosimilars and bringing them to the market is to increase access to biological medicines and reduce costs (compared with reference medicines). Access to healthcare is increasingly important around the world as we have aging populations and increasing incidence of chronic disease.
The NOR-SWITCH trial was a 52 week study where 482 patients who were previously on stable treatment regimen of Remicade originator were randomized to either continued Remicade originator treatment or to be switched to the biosimilar medication at the same dosing regimen. The primary endpoint of the study was disease worsening or falling outside of the non-inferiority margin of 15%.
Most of the patients in the analysis set had Crohn's disease (32%), with fewer having ulcerative colitis (19%), spondylitis (19%), RA (16%), PsA (6%) or psoriasis (7%).
The results showed no difference in disease worsening which occurred in 26% of the originator group and 30% of the biosimilar group. Differences between drugs for those with Crohn's disease appeared to be near significant, they were not. Adverse events were similar between groups, including adverse events leading to discontinuation (4% vs. 3%).
The NOR-SWITCH clinical trial appears to suggest that analytical proof of biosimilarity appears to be also result in similar clinical effectiveness.