Australian biotechnology company Percheron Therapeutics (ASX: PER) has achieved a critical milestone by completing a nine-month toxicology study for its lead drug, avicursen, an antisense oligonucleotide aimed at treating Duchenne muscular dystrophy. This study, conducted in non-human primates, is a critical regulatory requirement as Percheron advances toward clinical trials and FDA discussions to bring avicursen closer to market.
Avicursen Development and Toxicology Testing
Avicursen targets the CD49d biomarker, known for its role in inflammatory diseases such as Duchenne muscular dystrophy. The toxicology study began in March 2023 and represents a critical step in Avicursen’s therapeutic development. It involved an extended dosing period that concluded on schedule in December 2023. Following the dosing phase, a six-month recovery phase was conducted, during which avicursen was no longer administered to the subjects.
The recovery phase is a standard practice in toxicology studies, designed to determine whether any adverse effects that emerged during the dosing period are reversible after treatment cessation. The final results, obtained in June 2024, were consistent with a previous six-month study, confirming no deaths or unexpected toxicities. Any low-grade findings observed were fully reversible, indicating a favourable safety profile for avicursen.
CEO Dr. James Garner highlighted the importance of completing this study on schedule, particularly as it meets critical toxicology requirements set by the US Food and Drug Administration (FDA) for clinical trials. “We are very pleased to have this important piece of work completed on schedule,” he said. Dr. Garner emphasized that the study’s results provide confidence for the next phase of avicursen’s development and lay the groundwork for regulatory discussions with the FDA.
Preparing for FDA Regulatory Discussions
The successful completion of this study allows Percheron to move closer to FDA communications regarding the future of avicursen. The company is waiting for clinical data availability from a Phase IIb clinical trial currently underway. This trial focuses on non-ambulant boys with Duchenne muscular dystrophy and is expected to provide further evidence of avicursen’s immunomodulatory effects, which have shown promise in earlier research.
The Phase IIb clinical trial builds on a previous study that indicated positive signals of activity for avicursen. Initial data from the ongoing trial is expected to be available by the end of 2024. Percheron plans to incorporate these results into its submission package when it engages in regulatory discussions with the FDA in early 2025.
Dr. Garner explained that the company is focused on presenting the strongest possible data package to the FDA. “We want to be able to present the agency with the strongest possible package of data, with a view to enabling the conduct of future clinical trials and supporting a potential product approval in that market,” he said. This will ensure that Percheron meets all regulatory requirements and can potentially secure a clinical hold release, allowing the company to advance to the next stage of US commercialization.
Toxicology Study and Future Clinical Trials
The toxicology study results are a major step toward fulfilling the drug approval process for avicursen. Conducted under stringent conditions, the study provided valuable insights into the drug’s safety profile. As no new or unexpected toxicities were observed, and all adverse effects were fully reversible, the findings reinforce the potential for avicursen to move forward in the therapeutic development pipeline.
Avicursen’s mechanism of action involves reducing CD49d-positive lymphocytes, which could help manage a range of inflammatory diseases. This therapeutic approach holds promise not only for Duchenne muscular dystrophy but also for other conditions linked to inflammatory pathways. The primate toxicology testing provides confidence in the drug’s safety, particularly as Percheron prepares for further FDA communications in the coming months.
With a solid foundation from the toxicology study and upcoming clinical data from the Phase IIb trial, Percheron Therapeutics is well-positioned to advance avicursen’s development. If the early 2025 discussions with the FDA go as planned, the company could soon move into future clinical trials in the US, with the ultimate goal of achieving US commercialization and offering a new treatment option for patients with Duchenne muscular dystrophy.
As Percheron Therapeutics progresses through the drug approval process, the company remains focused on meeting all regulatory requirements and bringing avicursen closer to approval. The results from the toxicology study represent a significant step forward, and the company eagerly awaits further developments from its ongoing research efforts.