Biosimilars for the treatment of psoriatic arthritis

ABSTRACT

Introduction: In recent years, biosimilars of reference adalimumab (re-ADA), etanercept (re-ETN) and infliximab (re-IFX) have been licensed. In the absence of specific controlled studies, by the extrapolation principle, biosimilars have been approved for the treatment of psoriatic arthritis (PsA).

Areas covered: To assess the efficacy and safety of biosimilars in PsA, the literature, present until 30 June 2019, was reviewed. The literature search was undertaken using the PubMed database to identify English-language papers focusing on biosimilar efficacy in PsA. No specific PsA study was found, and the results were retrieved from trials on different inflammatory rheumatic diseases that were also enrolling patients with PsA. Data on re-IFX biosimilar CT-P13 and re-ETN SB4 were found, but not on re-ADA biosimilars. The results showed a trend toward a reduced efficacy of biosimilars. However, considering the small number of PsA patients, the non-statistically-powered studies, and the inappropriate outcome measures, these results could have occurred by chance.

Expert opinion: The few data do not allow to draw definitive conclusions, and emerging results suggest the need of specific trials, and of rigorous registries to evaluate the efficacy and safety of biosimilars in PsA.

KEYWORDS:

• Adalimumab
• anti-TNF biosimilars
• CT-P13
• etanercept
• infliximab
• psoriatic arthritis
• reference anti-TNFs
• SB4

Article highlights

• After the patent expiry of the respective originators, 6 adalimumab, 2 etanercept, and 3 infliximab biosimilars were licensed by the regulatory agencies in Europe and the USA.

• By extrapolation of indications, anti-TNF biosimilars were approved for the treatment of PsA.

• In the absence of specific trials, data of efficacy of biosimilars CT-P13 and SB4 were retrieved from PsA subgroups of studies on different inflammatory disorders.

• In 30 PsA patients enrolled in the NOR-SWITCH trial, CT-P13 did not reach the −15% non-inferiority cut-off of clinical equivalence.

• Overall, in comparison with the originators, a trend to a lower efficacy, and a higher discontinuation rate resulted in PsA patients receiving CT-P13 and SB4.

• The few available data, and the low grade of evidence do not allow to draw conclusive remarks, hence specific studies are required.

Declaration of interest

The authors have no relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript. This includes employment, consultancies, honoraria, stock ownership or options, expert testimony, grants or patents received or pending, or royalties.

Reviewer disclosures

Peer reviewers on this manuscript have no relevant financial or other relationships to disclose.

Additional information

Funding

This paper was not funded.