Sensorion (ALSEN) Status update summary

Program overview and regulatory milestones

• SENS-601, a gene therapy for GJB2-related hearing loss, has entered the clinic with French ANSM authorization for the HearConnex trial as of August 31, 2026, and first patient dosing targeted for early 2027 with data expected throughout that year.

• Clinical trial application approved in France, under review in Canada, with US IND and Australian CTA filings expected by year-end 2026.

• Enrollment will proceed as regulatory clearances are obtained, with sites in France, Canada, the US, and Australia already identified and trained.

• The program builds on years of inner ear biology expertise, leveraging collaborations with Institut Pasteur and prior clinical experience in cochlear delivery.

• The approach is designed to enable rapid transition to pivotal trials and broader patient populations, aiming to establish a franchise in genetic hearing loss.

Disease background and patient journey

• GJB2-related hearing loss is the most common recessive genetic cause of congenital deafness, affecting about 2,000 newborns annually in the U.S., EU4, and U.K.

• Early identification through newborn screening and genetic testing is critical, with universal genetic screening programs showing high parental acceptance and effectiveness.

• Current standard of care is cochlear implantation, which, while transformative, has limitations such as device dependency and lack of true binaural hearing.

• Gene therapy aims to provide physiologic, always-on hearing, potentially overcoming these limitations and enabling binaural integration.

Scientific and preclinical foundation

• The program is grounded in decades of genetic research, with GJB2 identified as the leading cause of congenital deafness and connexin 26 as the key protein.

• SENS-601 uses an AAV-DJ vector with a microRNA-based silencing mechanism to ensure selective expression in supporting cells, avoiding hair cells.

• Preclinical models, including conditional knockout mice, have clarified the role of connexin 26 in cochlear function and provided a platform for testing gene therapy.

• Preclinical studies in mice and non-human primates demonstrated robust, durable, and selective transgene expression, restoration of hearing thresholds, normalization of cochlear networks, and functional restoration of hearing.

• Safety studies showed good tolerability, limited biodistribution outside the target organ, and no concerning toxicity signals; the surgical procedure is well tolerated.