SAN FRANCISCO (AP) — One of the companies alleged to have conspired to keep generic versions of a popular opioid treatment off the market says the antitrust lawsuit has no merit.

Attorneys general for 35 states filed a complaint in the U.S. District Court for the Eastern District of Pennsylvania on Thursday, alleging that British drugmaker Indivior and New Jersey’s MonoSol Rx conspired to corner the market on Suboxone.

The drug is used to treat people hooked on heroin and other painkillers. MonoSol Rx chief executive Keith Kendall said in a statement Friday that the product has saved countless lives.

The complaint alleges the two companies conspired to make an oral strip form of the drug that they then marketed as safer than tablets, squashing competition.

Indivior has not responded to requests for comment.