Dr Reddy’s Laboratories Ltd (DRL) on Tuesday said an antitrust litigation has been filed in the US against the company along with several generic pharmaceutical firms, including Celgene and Bristol Myers Squibb.

In a regulatory filing, the Hyderabad-based company said a complaint was filed on November 18, in the District of New Jersey, USA, and it along with other generic pharmaceutical firms have been named as defendants.

“The complaint, which purports to be on behalf of a class of indirect purchasers, asserts claims under federal and state antitrust laws and other state laws alleging that the defendants improperly restrained competition and maintained a shared monopoly in the sale of brand and generic Revlimid through their respective settlements of patent litigation,” DRL said.

Revlimid is a prescription medicine used to treat adults with multiple myeloma in combination with dexamethasone, or as maintenance treatment after a type of stem cell transplant that uses an individual’s own stem cells.

According to DRL, the complaint “alleges that the challenged agreements improperly delayed generic entry entirely until 2022 and then improperly limited generic competition through 2026”. While the complaint sought damages, Dr Reddy’s asserted that “the allegations against it lack merit and will vigorously defend the litigation”.

Shares of the company were not affected by the announcement.