The objective of the phase III EGALITY study was to show equivalence in efficacy, safety, and immunogenicity of the etanercept biosimilar GP2015 and the originator product (ETN) in patients with chronic plaque psoriasis. We present the 30-week data comparing repeated switching with continued treatment.
Patients (N=531) with moderate to severe plaque psoriasis were randomized to receive 50 mg GP2015 or ETN twice weekly s.c. up to week 12. Patients with ≥50% improvement in psoriasis area and severity index (PASI 50) at week 12 were re-randomized to continue with the same treatment or to undergo 3 consecutive switches until week 30, each at 50-mg once-weekly.
The primary endpoint of equivalence in PASI 75 response at week 12 was met. At week 30, the pooled continued and pooled switched treatment groups (n=446, per-protocol set) showed similar PASI 75 response rates of 86.6% and 85.9%. The proportion of patients with ≥1 treatment-emergent adverse event (AE) and the types of AEs reported were similar between groups (continued 34.9%; switched 36.7%). Similar proportion of patients experienced injection site reactions with continued (4.3%) or switched treatments (4.6%). The incidence of antidrug antibodies (ADAs) over 30 weeks was low (1.9%, n=5, all in ETN group). At week 36, 12 weeks after the last of multiple switches, another patient switching from ETN to GP2015 found ADA positive. All ADAs were transient and non-neutralizing.
Equivalence in efficacy of GP2015 and ETN was observed in moderate to severe psoriasis patients. Multiple switching between treatments did not impact efficacy, safety, or immunogenicity. AEs were consistent with previous ETN trials in psoriasis.

Switching treatments of etanercept biosimilar GP2015 with originator product does not impact efficacy,  safety and immunogenicity in patients with chronic plaque-type psoriasis