WILMINGTON, N.C. (AP) — Drug development contractor PPD Inc. recently bought a vaccine testing laboratory from Merck & Co. as part of a partnership to provide the drug developer with testing services over the next five years. In addition to buying the 130,000-square-foot facility in Wayne, Pa, PPD also hired nearly 80 Merck employees at the site.Financial details of the deal, which closed on Dec. 31, were not disclosed. PPD said it will provide central laboratory and sample storage services for Merck. PPD said the acquisition significantly expands its global central laboratory business, adding vaccine and biologic testing, assay development and sample storage capabilities.