HSBC Bank USA, N.A., and Trinity Capital provided venture debt financing to Zenflow Inc. The size of the debt financing was not disclosed.
The debt further supports an oversubscribed $52 million Series D equity financing led by Cook Medical, Zenflow said in a 5 October 2026 announcement. ClavystBio joined as a new investor, alongside existing backers Invus Opportunities, F-Prime, Medtech Venture Partners and others.
Zenflow said proceeds from the financing will be used to accelerate the commercial launch of the Zenflow Spring System after the device received FDA premarket approval in December 2025.
Zenflow, based in South San Francisco, is developing the Zenflow Spring System, an office-based, reversible implant for benign prostatic hyperplasia, or enlarged prostate. The company also has an exclusive US distribution agreement with Cook Medical for Zenflow Spring.
The financing follows Zenflow’s $24 million Series C in November 2024. That round included Cook Medical as a new investor, along with existing investors Invus Opportunities, F-Prime, Medtech Venture Partners and others.