Former Amerigroup Corp. CEO James Carlson will leave WellPoint Inc., the company said Friday—three days after he lost a bid for the top job at the Indianapolis-based insurer.

Carlson will leave WellPoint on Feb. 28, according to a statement e-mailed by company spokeswoman Kristin Binns. He had joined the nation's second-largest health insurer in December, after WellPoint closed its $4.9 billion acquisition of Amerigroup.

WellPoint said Feb. 12 that it had chosen Joseph Swedish, CEO of the not-for-profit hospital system Trinity Health Corp., to be its next leader, ending a six-month search. Carlson, 60, was among the other candidates under consideration, a person familiar with the process told Bloomberg News last month.

“After helping close the Amerigroup transaction and assisting over the past six weeks with the integration of the two companies, Jim Carlson will be leaving WellPoint effective Feb. 28,” WellPoint said in the statement. “We wish Jim well, and thank him for his many contributions.”

While Carlson had signed a contract to remain with WellPoint for two years, the pact allowed the two sides to part under “changed circumstances,” said Carl McDonald, a Citigroup analyst, in a Feb. 13 note to clients. The WellPoint statement didn’t mention Carlson’s contract.

Binns declined to comment when asked how Carlson’s contract would be handled. WellPoint said last month that Richard Zoretic, Amerigroup’s former chief operating officer, would run its Medicaid business.