Safety, Efficacy of the Etanercept Biosimilar SB4 in Psoriatic Arthritis

Etanercept biosimilar SB4 is a cost-effective alternative therapy that can be considered for the treatment of patients with plaque psoriasis and psoriatic arthritis (PsA), according to a research letter published in the British Journal of Dermatology.

Researchers from the University of Rome conducted an observational, retrospective, single-center study of 40 patients with plaque psoriasis and PsA to determine the efficacy of etanercept biosimilar SB4 in this patient population.

Between October 2016 and March 2017, the investigators evaluated 21 men and 19 women (mean age: 55.10 years; range: 19.89 to 79.15 years) who received etanercept biosimilar SB4. At baseline and each follow-up visit, data were collected on psoriasis area severity index (PASI), visual analog scale for pain, erythrocyte sedimentation rate (ESR), C-reactive protein, tender joint count, and swollen joint count. Based on these data, the Disease Activity Score on 28 joints with ESR as a variable (DAS28-ESR) was calculated.

Within the study population, 35% of patients had plaque-type psoriasis (mean baseline PASI: 9.61); 65% had PsA (mean PASI, 4.69; mean DAS29-ESR, 5.27). Ten patients (25%) had previously received treatment with the etanercept originator via a 24-week intermittent regimen, interrupted at clinical resolution. No other treatment was administered between the original etanercept therapy and treatment with the SB4 biosimilar. Mean exposure of patients to the etanercept originator was 50.4 weeks (range: 24 to 96); average wash-out period between the originator and the biosimilar was 12.1 weeks (range: 8 to 24).

At 24 weeks, the mean PASI score significantly improved among those with plaque psoriasis or PsA (P <.0001 and P <.001, respectively). All markers, with the exception of swollen joint count, improved markedly but not significantly. Results from a sub-analysis of patients who had previously received the etanercept originator found no significant differences between PASI scores, DAS28-ESR, or VAS pain improvement vs patients who were etanercept naive. No serious adverse events were reported.

Study limitations included small sample size and a limited follow-up period. Despite this, the researchers concluded that etanercept biosimilar SB4 “is an effective treatment for patients [with plaque psoriasis and PsA] even if previously exposed to [the etanercept] originator.” In particular, they noted that this may be an observation of interest when price differences between the medications are considered — a savings of 61.58% and 62.55% for a 50 mg and 25 mg vial, respectively.

Disclosure

Dr Giunta reports working as a consultant and speaker for Abbvie, Biogen, Eli Lilly, and Pfizer. Dr Esposito reports working as a consultant and speaker at Abbvie, Eli Lilly, Pfizer, and Novartis. Dr Bianchi reports working as a consultant and speaker at Abbvie, Janssen, Pfizer, and Novartis.

Reference

Giunta A, Manfreda V, Esposito M, Del Duca E, Bianchi L. Etanercept biosimilar SB4 in the treatment of plaque-type psoriasis and psoriatic arthritis: a single-center, observational, retrospective, real-life study [published online May 3, 2019]. Br J Dermatol. doi: 10.1111/bjd.18090