Sensorion Confidentially Submits Draft F-1 for Potential U.S. IPO

Sensorion has confidentially submitted a draft registration statement on Form F-1 to the U.S. Securities and Exchange Commission as it evaluates a potential initial public offering in the United States. The French clinical-stage biotechnology company said the possible offering would involve its ordinary shares, including shares represented by American Depositary Shares, with the ADSs potentially listed on a U.S. national exchange.

The submission is an early regulatory step, not a completed public filing or a commitment to proceed with an offering. Sensorion has not disclosed the number of shares that could be offered, an expected price range, a target exchange, a proposed ticker or a timetable, and it said any offering would remain subject to market and other conditions.

The company announced the development on September 16, with the notice appearing in Euronext’s official Paris issuer-news feed. Sensorion is already a public company in France and trades on Euronext Growth under the mnemonic ALSEN, so the potential deal would be its first U.S. public offering rather than its first stock-market listing anywhere.

A confidential draft starts the SEC review before public filing

Submitting a draft Form F-1 confidentially allows an issuer to begin an SEC staff review without immediately publishing the registration statement and the detailed financial, business and risk disclosures that will eventually accompany a public filing if the offering moves forward. Form F-1 is the Securities Act registration form commonly used by foreign private issuers for U.S. securities offerings.

The distinction matters because Sensorion’s draft is not currently a public prospectus that investors can inspect on EDGAR. The SEC’s current guidance on nonpublic draft registration statements says issuers using the expanded review process submit a draft through EDGAR as a DRS. For an initial public offering under that process, the registration statement and prior nonpublic drafts must be made public at least 15 days before a road show, or at least 15 days before the requested effective date if there is no road show.

That means the confidential submission can begin a regulatory dialogue without fixing the offering terms. SEC staff may comment on disclosure and request revisions, while the issuer can amend the draft before deciding whether to file publicly. Sensorion’s September 16 announcement does not indicate how far the review has progressed or when the company might make a public filing.

American Depositary Shares would provide a U.S.-market wrapper around Sensorion’s ordinary shares if the company chooses that route. The announcement says ordinary shares could be included directly or in ADS form, but it does not specify an ADS ratio, the number of ADSs that might be sold or whether existing shareholders would participate alongside any newly issued shares.

The capital-markets step comes during a major pipeline reset

Sensorion develops therapies intended to restore, treat or prevent hearing loss. Its current lead gene-therapy program is SENS-601, an AAV-based candidate targeting hearing loss associated with mutations in the GJB2 gene. The company has described GJB2-related hearing loss as a major genetic cause of deafness and is developing the program across congenital, pediatric progressive and adult-onset settings.

The program became Sensorion’s lead gene-therapy asset in June, when the company said it would stop clinical development of SENS-501 for OTOF-related hearing loss and concentrate resources on SENS-601. Sensorion said at that time that the portfolio reprioritization extended its cash runway to the end of 2027. It also said a U.S. investigational new drug submission for SENS-601 was targeted by the end of 2026.

Since then, the company has reported further regulatory progress. Its current pipeline materials say the SENS-601 clinical trial application has been cleared in France, remains under review in Canada and is being prepared for U.S. and Australian submissions. The planned U.S. IPO has not been tied publicly to a specific trial, program or use of proceeds, so the F-1 step should not be read as evidence that any particular development expense will be financed through an offering.

Sensorion had already strengthened its balance sheet earlier in 2026. In its full-year 2025 update, the company said a January financing raised €60 million, including a €20 million strategic investment from Sanofi. The later extension of the stated runway to end-2027 followed the June pipeline reprioritization rather than a disclosed U.S. financing.

A public F-1 would provide the missing offering details

The next document that would materially change what investors can evaluate is a public registration statement. If Sensorion decides to proceed, a public F-1 would be expected to provide substantially more detail on the proposed securities, financial statements, risk factors, capitalization and the intended use of proceeds, subject to the disclosure included in the filing at that stage.

Until then, the scope of the potential offering remains open. Sensorion has said only that it is evaluating a U.S. IPO of ordinary shares, including ADSs, and a U.S. national-exchange listing of the ADSs. The company has not identified which exchange it would use or how a U.S. listing would interact with trading of its existing Euronext Growth shares.

The confidential submission also leaves the company free not to proceed if market or other conditions are not suitable. The concrete milestone to watch is therefore a public F-1 or another company announcement that supplies offering terms. Under the SEC process, a public filing would also make the nonpublic draft and amendments available on the timetable applicable to an issuer that moves ahead with an IPO.