Biosimilar SB15 Indicates Equivalent Efficacy to Aflibercept in nAMD Treatment

Se Joon Woo, MD, PhD

A new interim analysis indicated an equivalence in efficacy of SB15 and reference aflibercept in terms of best-corrected visual acuity (BCVA) at 8 weeks’ time in patients with neovascular age-related macular degeneration (nAMD).

Interim results from 32 weeks additionally demonstrated comparable clinical efficacy (BCVA/central subfield thickness [CST]), safety, immunogenicity, and pharmacokinetics of SB15 to reference aflibercept.

“The introduction of a safe and effective biosimilar may expand patients’ access to treatment options and support the implementation of an effective treatment regimen,” wrote study author Se Joon Woo, MD, PhD, Seoul National University Bundang Hospital.

The new data were presented at the American Academy of Ophthalmology 2022 Meeting.

Biosimilars can offer advantages to reference products without clinically meaningful differences, including being cost-effective for patients. SB15 is a proposed biosimilar of the reference aflibercept.

This phase 3, multicenter, randomized clinical trial was conducted to demonstrate the comparable clinical efficacy, safety, immunogenicity, and pharmacokinetics of SB15 to reference aflibercept in individuals with nAMD. Investigators presented the interim analysis results up to Week 32.

A total of 448 participants with treatment-naive nAMD and BCVA of 20/400 to 20/200 (letter score of 73 to 34, inclusive) were randomized 1:1 to intravitreal injection of 2mg SB15 or reference aflibercept for 48 weeks. Then, at week 32, those in the reference aflibercept group were rerandomized 1:1 by investigators to acquire switch data.

The primary endpoints were the change from baseline in BCVA at Week 8, with key secondary endpoints being the change from baseline in BCVA at Week 32 and change from baseline in CST at Week 32.

Data show 97.6% completed week 32 of the study, with a total of 449 patients randomized. After discontinuation, both SB15 and aflibercept had 219 patients at week 32 with a comparable mean number of injections.

Baseline characteristics were considered well-balanced. Each cohort had a mean age of 74 years with 118 female patients (52.7%) in the SB15 cohort and 132 female patients (58.7%) in the aflibercept cohort. The BCVA was 59.5 and 58.9, respectively.

The study primary endpoint was met, according to investigators. Data show the least squares mean change from baseline in BCVA at Week 8 was 6.7 letters for SB15 and 6.6 letters for aflibercept, at a mean difference 0.1 letters (95% confidence interval [CI], -1.3 to 1.4).

This was well contained within the previously defined equivalence margin of (-3 letters, +3 letters). Additionally, the least squares mean change from baseline in BCVA and CST over time up to Week 32 was comparable between SB15 and reference aflibercept.

There were no new safety signals identified, with a similar incidence and profile of treatment emergent adverse events between the two agents. A single intraocular inflammation event was identified only in reference aflibercept and no IOI event was observed in SB15.

The final 56-week findings are expected to be presented in the near future for additional long-term data of the biosmiliarity of SB15 to reference aflibercept.

The study, “SB15, a Proposed Biosimilar to Aflibercept, in nAMD: 32-Week Results,” was presented at AAO 2022.