Previous studies demonstrating equivalence of SB4 to etanercept in pharmacokinetics and safety have used pre-filled syringes, but these devices may be difficult for some patients to use if they have reduced hand dexterity due to the challenges of living with rheumatoid arthritis.
A crossover study comparing autoinjector and pre-filled syringe delivery methods of etanercept biosimilar SB4 showed bioequivalent pharmacokinetic parameters and similar safety profiles following a single administration in healthy men.
SB4, the etanercept biosimilar from Samsung Bioepis, which is sold as Benepali in European countries, was approved by the US FDA in 2019 for all indications of its originator (Enbrel). Switch studies have suggested that SB4 is similar in safety and effectiveness in patients switching from the originator.
According to the authors, previous studies demonstrating equivalence of SB4 to etanercept in pharmacokinetics and safety have used pre-filled syringes. However, these devices may be difficult for some patients to use if they have reduced hand dexterity due to the challenges of living with rheumatoid arthritis.
Autoinjector pens can provide an improved injection experience for these patients, resulting in better medication adherence. The authors also note that SB4 autoinjectors have demonstrated ease of use compared to originator etanercept in previous surveys of patients, nurses, and rheumatologists.
This phase 1, open-label, single-dose crossover study measured pharmacokinetics following a single dose of SB4 in 44 healthy men in The Netherlands. Participants were assigned to 1 of 2 sequences, in which they received a single 50 mg dose of SB4 via autoinjector or pre-filled syringe, followed by a 14-day washout period, and then a single dose via the other delivery method.
Mean values of the primary pharmacokinetic endpoints (area under the concentration-time curve from time zero to infinity (AUCinf), time zero to the last quantifiable concentration (AUClast), and maximum serum concentration (Cmax)) were similar between delivery methods. The ratios of autoinjector to pre-filled syringe methods for these pharmacokinetic factors for all fell within the pre-defined equivalence range of 80-125%. Comparing pharmacokinetic parameters in subgroups by body weight, the effect of body weight on pharmacokinetics also appeared similar between both delivery methods.
Autoinjector delivery was well tolerated, although treatment-associated adverse events were somewhat (64.0% of participants compared to 46.7% in the pre-filled syringe group). The most common adverse events overall were headache, oropharyngeal pain, pruritus, neutropenia, and rhinitis, and no serious adverse events occurred. Additionally, there were no severe injection site reactions for either delivery method.
Shin D, Kim Y, Go A, Velinova M. Comparison of the pharmacokinetics, safety, and tolerability of the autoinjector (AI) and pre-filled syringe (PFS) of SB4 in healthy subjects [published online January 8, 2020]. Drug Des Devel Ther. doi:10.2147/DDDT.S224103