Sensorion shares fell after the French medicines regulator authorized the company to start HearConnex, a Phase I/II trial in France for its gene therapy SENS-601 targeting hearing loss linked to GJB2 mutations. The approval from France’s ANSM came through the agency’s Fast Track assessment pathway, but the stock still closed lower as investors balanced the clinical milestone against broader biotech sentiment and upcoming milestones.
Key takeaways
- Price move: Sensorion shares closed Wednesday at €0.257, down 3.38%.
- Catalyst: ANSM authorized initiation of HearConnex, a Phase I/II trial of SENS-601 for GJB2-related hearing loss in France.
- Trial design: The study is structured in two parts, starting with safety and tolerability after unilateral dosing, followed by efficacy evaluation after bilateral dosing.
- Implication: The authorization advances Sensorion’s clinical program in Europe, while timing expectations place initial patient dosing in France in early 2027 and data generation throughout 2027.
What drove the move
Sensorion said the French National Agency for Medicines and Health Products Safety (ANSM) has granted authorization to initiate HearConnex, the company’s Phase I/II clinical study of SENS-601 for GJB2-related hearing loss. Importantly for drug developers, ANSM awarded the authorization following its Fast Track assessment procedure, a regulatory pathway intended to speed review for selected therapies.
The company linked the approval to multi-year collaboration with Professor Christine Petit, whose preclinical work reported meaningful hearing restoration with SENS-601 in animal models that were described as clinically relevant.
How HearConnex is structured
HearConnex is planned as an open-label, two-part study.
- Part 1 will focus on safety and tolerability. It will enroll participants receiving unilateral intra-cochlear administration across two ascending-dose cohorts.
- Part 2 will evaluate efficacy using an expansion cohort after bilateral intra-cochlear administration at the selected dose from Part 1.
Beyond clinical outcomes, Sensorion said the study will also assess the safety and usability of its injection system, an important factor for gene therapy trials that rely on precise delivery into target tissues.
Timeline and parallel regulatory progress
Site set-up in France is underway, with Sensorion targeting dosing of the first patient in early 2027. The company expects clinical data generation throughout 2027, aligning the regulatory green light with a longer runway typical for early-stage gene therapy programs.
Sensorion also highlighted ongoing international regulatory activity. It said Health Canada remains on track with its review of the Clinical Trial Application it submitted in June 2026. The company is targeting additional filings, including a CTA in Australia and an Investigational New Drug (IND) application in the United States by year-end 2026.
Reverse split may shape near-term trading
Separately, Sensorion recently announced a 50-for-1 reverse stock split, under which every 50 existing shares with a €0.10 par value will be consolidated into one new share with a €5 par value. The reverse split began August 13, 2026 and is scheduled to take effect September 15, 2026, covering 515.65 million existing shares.
Over the last year, the stock has traded in a range between €0.222 and €0.808. On Wednesday, it closed at €0.257, down 3.38%, reflecting a trading session where investors appeared to weigh the regulatory milestone against the company’s longer clinical timeline and ongoing execution demands.
Sensorion said it will host an online SENS-601 Program Day on September 22, 2026, focused on the underlying science, the patient population, and the design and endpoints of HearConnex.
Investors will be watching for updates on regulatory outcomes in Canada and other jurisdictions, as well as confirmation of France site readiness and enrollment pace ahead of first dosing targeted for early 2027. The next major inflection points for the program include clinical start-up execution in France and forthcoming data readouts expected across 2027.
