Sensorion raised €60M backed by €20M from Sanofi to advance gene therapies for hearing loss

The Montpellier-based biotech said its cash runway has been extended to the first half of 2027, and, according to the announcement, “The settlement-delivery of the Reserved Offering is expected to take place around January 30th, 2026, subject to customary conditions.”

Pushing forward genetic solutions

Sensorion’s pipeline focuses on innovative therapies designed to deliver long-term benefits for patients with, or at risk of, inner ear disorders. The assets include two gene therapies (SENS-501 and SENS-601) targeting genetic forms of hearing loss, and a first-in-class small-molecule (SENS-401) being developed to treat sudden sensorineural hearing loss.

In today’s announcement, the biotech company said the new raise will support the advancement of its genetic programs, key catalysts for the company at this stage.  “With the additional capital, the company plans to intensify the ongoing efforts to progress the research and development of SENS-601, including the advancement of the program into its clinical development, and to continue the clinical development of SENS-501 program,” stated Nawal Ouzren, CEO of Sensorion, in the press release.

Specific milestones for this quarter include regulatory approval of the Clinical Trial Application (CTA) and Investigational New Drug (IND) applications for SENS-601 (also known as GJB2-GT), along with first patient enrollment. SENS-601 is designed to treat congenital deafness, progressive hearing loss in children, and early presbycusis in adults. The company also said it will continue the clinical development of SENS-501 (also known as OTOF-GT) for otoferlin deficiency, anticipating a clinical readout of six-month follow-up data from the second cohort of the Phase 1/2 Audiogene trial. Moreover, Sensorion plans to share Phase 2a results from the Notoxis study of the SENS-401 small molecule in cisplatin-induced ototoxicity.

A wave of interest in gene therapy for hearing loss

This news comes the same day that Seamless Therapeutics GmbH (a Dresden-based biotech company with its US Inc. subsidiary based in the Boston area) has signed a worldwide strategic research and licensing agreement with Eli Lilly,  with the goal of developing and subsequently commercializing a programmable, recombinase-based gene therapy for selected forms of genetically caused hearing loss.

Under the Seamless-Lilly agreement, Seamless brings its proprietary recombinase platform, enabling precise, large-scale DNA insertions and modifications without relying on the cell’s natural DNA repair pathways. This approach sets it apart from the more commonly used CRISPR/Cas tool for DNA modifications (often referred to as “molecular scissors”). In contrast, Sensorion’s gene therapies are more “traditional” AAV-based approaches. Each approach comes with its own challenges: Seamless’s early preclinical platform has not yet been tested in humans, and even CRISPR/Cas technologies (one of the closest existing technologies under development) have limited clinical data and unknown long-term effects. Meanwhile, Sensorion’s well-established AAV-based gene therapies have a longer track record in humans, but their use can trigger immune responses that may limit effectiveness or prevent repeat dosing. So far, three patients (aged between 6 and 31 months) were treated with Sensorion’s SENS-501 gene therapy, and “the surgical procedure was well tolerated, and intra-cochlear administration of SENS-501 was uneventful, and no serious adverse events or serious side effects have been reported,” said the company.

The new funding positions Sensorion to focus on advancing its lead gene therapy programs through critical regulatory and clinical milestones over the coming months. With strong backing from existing investors and the strategic entry of Sanofi, the company is well placed to continue building the clinical evidence needed to bring potentially transformative treatments for genetic hearing loss closer to patients.