Some of Premier Research Group’s top management made a preliminary approach to its board, exploring an offer to buy the contract research organization (CRO), according to Thomson Financial.

London-based Premier said that there can be no guarantee that this initial approach will lead to an offer being made for the company.

Premier has been on acquisition spree by buying six CROs since it went public in London in 2004. In July, the company purchased its latest two CROs. Premier bought ARS Inc., based in Boston, and D-TARGET SA, located in Switzerland.

Premier expects ARS will strengthen its presence in the New England biotech market while D-Target's medical device focus will bring expanded expertise in that area to customers in the United States and Europe. The acquisitions continue Premier’s strategy of building an international business both organically and through strategic acquisitions.

Since January, Premier’s shares in London have fallen significantly, but closed up 13.6% on August 29.