Retension Pharmaceuticals (RTSN) files S-1 for Nasdaq IPO

As seen on the 24/7 Wall St. homepage on September 18, 2026.

THE IPO WIRE
Retension Pharmaceuticals, Inc. RTSN · Nasdaq

Retension Pharmaceuticals files for Nasdaq IPO

Another biotech is testing the reopened IPO window: Retension Pharmaceuticals registered an S-1 to list on Nasdaq. Leerink Partners, Guggenheim Securities, Oppenheimer and Titan Partners are running the books, a four-bank syndicate that signals a real deal. Terms and deal size come with the first amendment.

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Retension Pharmaceuticals has filed an S-1 registration statement with the SEC, formally starting the clock on what would be a Nasdaq debut. The filing puts the company in the queue of biotechs probing an IPO market that has shown signs of reopening after a prolonged drought.

The syndicate behind the deal is a telling signal of intent. Leerink Partners, Guggenheim Securities, Oppenheimer, and Titan Partners are all named as bookrunners, a four-bank lineup that typically reflects serious institutional backing and a coordinated effort to build a broad investor book.

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Pricing terms and deal size have not yet been disclosed, as is standard for an initial S-1 filing. Those figures will appear in the first amendment to the registration statement, which is the next concrete milestone to watch for.

For investors tracking the biotech IPO pipeline, the composition of the banking syndicate and the speed of the first amendment filing will be early indicators of how aggressively Retension plans to move and how much institutional demand the company believes it can attract.

Sources

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