March 1 (Reuters) - Endo International Plc said on Thursday it had obtained a preliminary injunction preventing privately-held QuVa Pharma Inc from marketing and releasing a compounded drug that could rival its blood pressure shot Vasostrict.

The injunction was issued by U.S. District Judge Brian Martinotti in Trenton, New Jersey, to two Endo subsidiaries which are suing QuVa, claiming its compounded product misappropriates trade secrets related to Vasostrict.

Bulk compounding, whereby facilities are able to prepare tailored doses of drugs for individual patients, has become a widespread practice in the United States.

Endo separately filed a lawsuit against the U.S. Food and Drug Administration (FDA) in October, accusing the agency of improperly authorizing the bulk compounding of hundreds of drugs, including "essentially a copy" of Vasostrict.

Endo has since put that lawsuit on hold and the FDA is expected to issue new criteria this month for determining what substances can be used to produce drugs in bulk for hospitals and doctors' offices without individual patient prescriptions.

A 2013 law permitted "outsourcing facilities" that could register with the FDA and sell compounded products in bulk without prescriptions for individual patients in accordance with federal manufacturing standards.

Vasostrict, indicated to increase blood pressure in adults with vasodilatory shock, was approved by the U.S. regulator in 2014.

QuVa was founded in 2015 by former executives at Endo's subsidiary Par Sterile Products Llc.

The company's lawyers did not immediately respond to a request for comment. (Reporting by Tamara Mathias in Bengaluru; Editing by Daniel Wallis)