Emphasys Medical, maker of a valve that diverts air to only the healthy parts of lungs in emphysema patients, has put itself up for sale after the Food and Drug Administration rejected its lead product in December. This is the second relatively recent defeat for the Redwood City, Calif.-based company, which had to withdraw its IPO filing last May. Since then, all but five of its 50 employees have been laid off.

Founded in 2000, Emphasys had raised $90 million in capital and debt to develop and commercialize its product, called the Zephyr Endobronchial Valve, which quickly earned European market clearance in 2003, according to VentureWire. So the FDA’s 11-2 vote against it came as somewhat of a surprise, and the company was unable to retool and try again. Instead, it retained Gerbsman Brothers to help it find an appropriate buyer that might have the heft to urge FDA approval.

Previously, Emphasys raised $75 million in equity and $15 million in debt from the likes of Advanced Technology Ventures, Morgenthaler Ventures, St. Paul Venture Capital, ABS Ventures, Morgan Stanley Venture Partners, Cargill Ventures, New Enterprise Associates and OrbiMed Advisors.