Regenerative medicine company Tengion‘s (Nasdaq: TNGN) Chief Scientific Officer Timothy Bertram will handle CEO duties while the company searches for a new top executive.

Former CEO Dr. Steven Nichtberger resigned from the company on June 30. No reason was given for the resignation, but the company had said in securities filings that his departure “is not the result of a disagreement with the company.” Board Chairman David Scheer said in Tengion’s second-quarter earnings release that a search for a new CEO is under way.

In an Aug. 9 filing, Tengion said that Bertram, Tengion’s CSO and executive vice president of science and technology, will take on the additional functions of the top executive. Bertram has been with Tengion since 2004 and he leads the company’s R&D efforts. His experience includes executive positions at Pfizer (NYSE: PFE) and SmithKline Beecham.

Tengion went public in 2010 and raised $31 million through a stock sale this past March.

Tengion’s tissue regeneration technology was originally developed at Wake Forest University based on the research of Dr. Anthony Atala, director of the Wake Forest Institute for Regnerative Medicine. The technology can create organs and tissues that the body will recognize as its own. Tengion is headquartered in East Norriton, Pennsylvania but maintains its R&D operations and the bulk of its staff in Winston-Salem.

Tengion’s tissue regeneration technology has received an orphan drug designation from the U.S. Food and Drug Administration for addressing an unmet medical need. Tengion is currently testing its technology to help patients who have had their bladder removed due to bladder cancer. The technology is used to fashion a new conduit to carry urine from the body.

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