Advancing AAV therapies to regulatory approval - Eurofins BPT supports methods for EU release

Mirinda Tattan, PhD, Technical Consultant, Advanced Therapies, Eurofins BioPharma Product Testing Ireland, Mirinda.Tattan@bpt.eurofinseu.com

The genetic medicine landscape continues to accelerate, with rapid advances across modalities, including lentiviral ex vivo therapies, CRISPR‑based gene editing, and RNA/oligonucleotide technologies. Among these, in vivo AAV (Adeno‑Associated Virus) gene replacement therapies represent the largest portion of late‑stage clinical pipelines and the majority of gene therapies progressing toward regulatory approval. AAV vectors deliver a functional gene directly to patient cells using a replication‑incompetent viral system – an approach that introduces unique analytical challenges due to biological complexity, lot‑to‑lot variability, and inherently small batch sizes.

Since 2017, approximately 10 AAV therapies have received FDA approval, with seven also approved by the EMA. While both agencies maintain rigorous review standards, their approaches to QC release requirements differ. The FDA typically applies a flexible, risk‑based philosophy, whereas the EMA requires a more prescriptive, fully developed analytical package prior to commercialisation. In the EU, AAV gene therapies fall under the category of Advanced Therapy Medicinal Products (ATMPs) and, importantly, are not covered by any Mutual Recognition Agreements. As mandated by EU Directive 2001/83/EC, Article 51(1)(b), ATMPs must undergo in‑country testing within an EU member state before market release.

To meet EMA expectations, manufacturers must apply orthogonal analytical strategies for each Critical Quality Attribute (CQA), including identity, potency, purity, quantity, safety, and stability. The accompanying table outlines these CQAs and the gold‑standard analytical methods typically required.

At Eurofins BPT Ireland, we are exceptionally well positioned to support clients preparing AAV therapies for the European market, with extensive experience in the commercial release of AAV programmes and in generating data packages for regulatory filings. As shown in the accompanying table, our laboratory delivers the complete suite of QC methods required for both AAV drug substance and drug product, supported by deep technical expertise in method development, validation, transfer, and comparability assessments essential for EMA submissions. Leveraging our strong track record in producing robust regulatory‑ready datasets, we help de-risk submissions and accelerate programme progression right through to commercial release.

Significant recent investment has further strengthened our gene therapy offering, including the expansion of our Biosafety Level 2 facilities and the addition of a purpose-built laboratory dedicated to AAV potency testing. We are also proud to be the first contract testing laboratory in Europe to offer GMP AUC, underscoring our leadership in advanced AAV characterisation and our commitment to expanding industry leading and life-enhancing capabilities.

With cutting‑edge capabilities, regulatory expertise, and a proven record in supporting commercial release for global gene therapy programs, Eurofins BPT Ireland stands ready to help bring the next generation of transformative AAV therapies to patients across Europe.

For more information contact us at: EurofinsBPT-IE@bpt.eurofinseu.com or visit: www.eurofins.com/biopharma-services/product-testing/locations/ireland/.