Pfizer Inc said it received subpoenas from the U.S. Attorney's Office for the District of Massachusetts related to its support for organizations that provide financial help to Medicare patients.
"Pfizer is among a number of companies that have received subpoenas regarding this matter," the New York-based company said in an emailed statement on Friday.
Drugmakers including Valeant Pharmaceuticals International Inc and Regeneron Pharmaceuticals Inc have disclosed involvement in similar government investigations.
In a regulatory filing on Thursday, Pfizer said the December 2015 and July 2016 subpoenas were related to groups that help cover patient co-payments for prescription drugs.
Medicare is the U.S. government healthcare plan for seniors.
As aggressive price increases for certain prescription medications have drawn the ire of politicians and the healthcare industry, concern has grown that donations made by pharmaceutical companies to patient assistance groups may be contributing to the price inflation.
"We support initiatives, including co-pay foundations, to help patients most in need gain access to medicines," Pfizer said. "We strive to follow government guidelines associated with any contributions we make."
Pfizer said it has been providing information to the government in response to the subpoenas.
(Reporting by Deena Beasley; Editing by Cynthia Osterman and Leslie Adler)