AEON's ABP-450 Achieves Critical Analytical Milestone, Demonstrating High Biosimilarity to BOTOX

AEON Biopharma has announced a significant milestone in its biosimilar development program with the release of robust analytical data demonstrating that ABP-450 (prabotulinumtoxinA) is highly similar toonabotulinumtoxinA (BOTOX).¹ The results were submitted to the US Food and Drug Administration (FDA) ahead of a scheduled Biosimilar Biological Product Development (BPD) Type 2a meeting on November 19, 2025. These findings provide early but compelling evidence that ABP-450 may satisfy the stringent analytical foundation required under the 351(k) biosimilar pathway.

Primary Structure Results

Using high-sensitivity liquid chromatography and mass spectrometry (LC/MS), investigators analyzed over 3,400 peptides derived from 3 independent lots of ABP-450 and 2 lots of BOTOX. Sequence coverage ranged from 93% to 99% across all 5 constituent proteins of the 900 kDa botulinum toxin type A complex. Importantly, no amino acid differences or minor sequence variants were detected. According to AEON, this level of structural concordance satisfies a critical prerequisite for establishing biosimilar functional comparability and reduces residual uncertainty at the earliest stage of regulatory review.

Functional Analyses

Furthermore, initial functional analyses demonstrated similarity across several key performance attributes. Potency was assessed using 2 orthogonal approaches: the LD50 assay, which measures in vivo biological activity, and a cell-based potency assay (CBPA). ABP-450 performed in close alignment with BOTOX in both systems, supporting the potential for predictable clinical dosing. Composition studies using ELISA further showed comparable vial-to-vial active ingredient levels, reinforcing the reliability and consistency of the ABP-450 manufacturing process.

Enzymatic activity evaluation—a core indicator of BoNT/A’s mechanism of action—confirmed that ABP-450 effectively cleaves SNAP-25. Some lot-to-lot variability was observed, but the company reported that the values remain within standard analytical expectations and anticipates tighter convergence as additional lots undergo analysis. Collectively, these functional data provide supportive evidence that ABP-450 mirrors the biological behavior of the reference neurotoxin.

Next Steps

From a strategic perspective, AEON aims to achieve the first full-label BOTOX therapeutic biosimilar designation in the US, a position that could reshape a therapeutic neurotoxin market valued at more than $3 billion annually. Dermatology clinicians may be particularly interested in this development as therapeutic use of botulinum toxin extends beyond cosmetic procedures into indications such as hyperhidrosis, neuropathic and musculoskeletal pain syndromes, and other conditions where access and cost can limit patient care.

“We believe these results mark a major step forward in AEON’s 351(k) biosimilar pathway for ABP-450,” said Rob Bancroft, AEON’s President & Chief Executive Officer. “The confirmation of identical amino acid sequencing, together with strong similarity in potency and composition, provides compelling early evidence of biosimilarity to BOTOX. We expect the functional dataset to continue to strengthen as additional lots are evaluated. Importantly, these data build upon the extensive global body of evidence for ABP-450, which is already approved in 69 countries and manufactured at commercial scale by our partner Daewoong Pharmaceutical in FDA- and EMA-inspected facilities. Together, we believe these factors substantially de-risk our U.S. program and set the stage for constructive discussion with FDA this month.”¹

The upcoming FDA BPD Type 2a meeting on November 19 will determine the next steps in ABP-450’s biosimilarity review.

Reference

1. AEON Biopharma Reports Positive and Robust Biosimilarity Results: Identical Amino Acid Sequence and Highly Similar Functional Analysis Data. News release. BioSpace. Published November 14, 2025. Accessed November 17, 2025. https://www.biospace.com/press-releases/aeon-biopharma-reports-positive-and-robust-biosimilarity-results-identical-amino-acid-sequence-and-highly-similar-functional-analysis-data