(Adds Vertex response, details on CVS)
Oct 30 (Reuters) - Vertex Pharmaceuticals Inc said it received a subpoena from the U.S. Department of Justice in the third quarter related to its marketed medicines, seeking documents related primarily to its "good laboratory practices" in a bioanalytical lab.
Good laboratory practices are rules that govern non-clinical safety studies, ensuring quality, integrity and reliability of data. Bioanalytical labs measures drug levels in biological samples, specifically in blood and urine.
"We are in the process of responding to the subpoena and intend to cooperate," Vertex said in a securities filing.
The subpoena will not impact the safety, effectiveness and commercialization of the company's existing drugs or those in development, Vertex spokesman Zach Barber told Reuters.
Shares of the cystic fibrosis drugmaker were marginally down after-hours.
Separately, drugmaker Mylan NV and drugstore chain CVS Health Corp said in their quarterly filings that they had received subpoenas from federal agencies.
CVS said the Drug Enforcement Administration (DEA) in September sought documents related to controlled substance policies, procedures and practices at eight pharmacy locations since May 2012.
Last May the company agreed to a fine of $22 million in a settlement with the U.S. Attorney's Office for the Middle District of Florida, resolving alleged violations of the Controlled Substances Act.
CVS, in its filing, said it is undergoing several audits by the DEA and is in discussions with the agency and the U.S. Attorney's office in several locations concerning allegations that it has violated certain requirements of the CSA.
Mylan said the U.S. Securities and Exchange Commission was seeking documents with regard to certain "related party matters."
CVS and Mylan's shares were little changed after the bell. Neither company was immediately available for comment. (Reporting by Natalie Grover and Ramkumar Iyer in Bengaluru; Editing by Anil D'Silva and Leslie Adler)