France’s ANSM has authorized the Phase I/II HearConnex clinical trial of SENS-601, Sensorion’s investigational AAV-based gene therapy targeting one of the most common causes of genetic congenital deafness, with patient dosing targeted for early 2027.
Sensorion has received authorization from France’s National Agency for Medicines and Health Products Safety (ANSM) to initiate HearConnex, a Phase I/II clinical trial evaluating SENS-601, the company’s lead gene therapy candidate for GJB2-related hearing loss. The authorization was granted on Aug 31, 2026, under the ANSM’s Fast Track assessment process, which provides a significantly reduced review period relative to the standard regulatory pathway.
Pathogenic variants in the GJB2 gene are among the most common causes of genetic deafness, accounting for approximately 50% of autosomal recessive non-syndromic hearing loss, and no approved treatment addressing the underlying cause currently exists.
Trial Design and Timeline
HearConnex is designed as a two-part, open-label study. Part 1 will assess the safety and tolerability of SENS-601 following unilateral intra-cochlear administration across two ascending-dose cohorts. Part 2 will assess efficacy in an expansion cohort following bilateral intra-cochlear administration at the selected dose. The trial will also evaluate the safety, tolerability, performance, and usability of Sensorion’s proprietary injection system.
Site start-up activities in France are now underway, with dosing of the first HearConnex patient targeted by early 2027. Clinical data generation is expected throughout 2027.
Recent research has also established that GJB2 mutations are found in early-onset forms of severe presbycusis in adults, which appear to be monogenic and potentially treatable by gene therapy.
HearConnex is designed as a multi-regional trial. The review by Health Canada of a clinical trial application submitted in Canada in June 2026 remains on track, and Sensorion is targeting submission of a clinical trial application in Australia and an Investigational New Drug (IND) application in the US by year-end 2026.
Investigators and Institutional Partners
The coordinating investigator for HearConnex is Dr Sharon Cushing, pediatric otolaryngologist and director of the Cochlear Implant Program at The Hospital for Sick Children (SickKids) in Toronto, who will also serve as principal investigator for the Canadian site, subject to completion of the ongoing regulatory review.
“We are entering an important new chapter in the treatment of hearing loss, one that carries both excitement and important scientific questions still to be answered,” says Dr Cushing, in a release. “With the courage and trust of the patients and families who take part in HearConnex, we look forward to learning as the program advances, and to the insights this trial will generate.”
The principal investigator for the French site is Prof Natalie Loundon, MD, director of the Center for Research in Pediatric Audiology, pediatric otolaryngologist and head and neck surgeon at Necker Enfants Malades, AP-HP, in Paris.
“Children born with GJB2-related hearing loss, and their families, hope for additional therapeutic options that address the underlying cause of the condition. Bringing gene therapy into the clinic for this population requires a highly specialized surgical and audiological environment, and the teams involved have built this experience over the years notably through the course of our Audiogene clinical trial,” says Prof Loundon, in a release. “We are glad to take part in HearConnex from the outset and to contribute to a rigorous evaluation of SENS-601 in this patient population.”
The clinical trial application approval follows extensive work conducted in collaboration with Prof Christine Petit’s team at Institut Pasteur–Institut de l’Audition/Institut reConnect, which has generated data demonstrating significant hearing restoration following SENS-601 administration in clinically relevant animal models. These findings were supported by a preclinical package assessing the toxicology and activity of SENS-601, alongside GMP manufacturing of the gene therapy drug product for the clinical trial.
“Securing approval to initiate HearConnex marks a significant milestone for Sensorion and, above all, for the children and families affected by congenital DFNB1A hearing loss, for whom no treatment addressing the underlying biological cause of the disease exists today,” says Fred Chereau, CEO of Sensorion, in a release. “It reflects the depth of the science built over many years with our partners at the Institut Pasteur–Institut de l’Audition/Institut reConnect, as well as the overall quality of the dossier assembled by our multidisciplinary teams.”
About SENS-601
SENS-601 is an AAV-based gene therapy developed in collaboration with Prof Petit’s team to treat hearing loss linked to mutations in the GJB2 gene, which plays a critical role in maintaining the ionic balance necessary for sound transduction in the inner ear. Recent research has also established that GJB2 mutations are found in early-onset forms of severe presbycusis in adults, which appear to be monogenic and potentially treatable by gene therapy. The program is partially funded by the French State as part of the France 2030 investment plan.
SENS-601 Program Day
Sensorion will host an online SENS-601 Program Day on Sept 22, 2026, covering the underlying science, patient population, and the design and endpoints of HearConnex. External speakers will include Prof Petit and Dr Cushing, joined by members of Sensorion’s management team. Registration details will be available at sensorion.com.
For more on Sensorion’s previous SENS-601 program updates, see The Hearing Review‘s earlier coverage:
Featured image: Dreamstime
