Just as Merck & Co is getting to finalise a $4.85 billion settlement with thousands of claimants over Vioxx, the state of Florida has hit the company with a lawsuit demanding damages of over $80 million for what it claims was deceptive marketing of the withdrawn painkiller.

Florida’s Attorney General Bill McCollum is suing Merck over what he claims was the company’s “repeated failure to disclose the adverse effects” of Vioxx (rofecoxib) while offering it to the state’s Medicaid programme as a safe painkiller. The C)X-2 inhibitor was removed from the market in 2004.

The lawsuit follows a three-year investigation which alleges that “due to the company’s marketing practices, numerous state agencies approved the inclusion of Vioxx as a covered or approved drug and agreed to reimburse or pay for it. Vioxx purchases by the Florida Medicaid programme alone exceeded $80 million between 1999 and 2004.

Furthermore, the lawsuit claims Merck’s “costly promotional campaign was intended to convince purchasers that the drug was not only safe, but that they should demand it from their health care professionals for pain treatment”. The company also “allegedly tried to intimidate physicians and researchers who questioned the safety of Vioxx and may have misrepresented or concealed published evidence, including its own, showing possible harmful effects of the drug”.

The Attorney General said that if the facts about Vioxx had been known earlier, doctors and their Medicaid patients “would have chosen other, less expensive prescriptions”. Florida is looking to recoup the cash it paid out, plus interest, and also seeks civil penalties of up to $10,000 per violation of the law.

Merck says it acted responsibly, and “we intend to defend against the complaint filed by Florida”. The company says the suit appears similar to Medicaid-related suits previously filed by other states – Alaska, Louisiana, Michigan, Mississippi, Montana, New York, Texas and Utah.

The New Jersey-based firm has already paid out $58 million under a settlement reached in May to end allegations that its advertisements for Vioxx downplayed potential health risks. That settlement ended cases brought by 29 states (including Florida) and the District of Columbia and also required Merck to submit TV commercials for its drugs to the US Food and Drug Administration for review.

The Florida charge comes just as Merck is going through the cases involved in a $4.85 billion settlement the company has agreed which will end about 50,000 lawsuits by people alleging Vioxx caused heart attacks or strokes.