A New York-based investment firm has bought a 5 percent stake in Durham-based Fennec Pharmaceuticals Inc. and states that it believes the biotech company’s stock is “undervalued,” according to a filing with the Securities and Exchange Commission.

Varana Capital LLC is based in Manhattan near Grand Central. It said in the filing that it bought the shares because the company is “an attractive investment opportunity.”

Its managing partner is Philip Broenniman, who started the firm in 2012. Broenniman was previously a portfolio manager and managing partner of Cadence Investment Partners LLC, a hedge fund started in 2003.

His partner is Ezra Gardner, who was a co-founder and portfolio manager of Omnium Capital Management. Prior to Varana, Gardner served as lead project manager and managing partner at KCPS/Omnium Capital Management.

Fennec Pharmaceuticals is a small stage biotechnology company focused on the development of sodium thiosulfate for the prevention of loss of hearing in pediatric cancer patients.

Children undergoing chemotherapy face the loss of hearing. Fennec Pharma hopes that sodium thiosulfate will allow these children to keep their hearing and prevent permanent disability.

The drug has received orphan drug designation, which means it is intended for the safe and effective treatment, diagnosis or prevention of rare diseases and disorders that affect fewer than 200,000 people in the U.S.

Fennec’s shares closed Friday at $3.70, up 20 cents, or 5.7 percent.