The companies named in the suit are Purdue Pharma, Endo Pharmaceuticals, and Janssen Pharmaceuticals.
"These companies knew that the drugs they sell and market are highly addictive, even life-threatening if misused. And yet they have engaged in a deliberate campaign of fraud to convince Missouri doctors and Missouri consumers otherwise.
"They used bogus front organizations and fake research; they used fraudulent advertising and deceptive trade practices. And they repeatedly lied about the risks and true nature of the drugs they sold," Hawley said at a news conference. "Their fraud has been devastating."
Hawley says 500 Missourians died of opioid overdoses or complications and 300 more died from heroin misuse in 2015.
"In 2012, physicians wrote some 259 million opiod prescriptions in the United States -- that's 10 million more prescriptions than there are adults living in the United States of America," he said.
Companies respond to lawsuit
The three manufacturers named in the suit responded to its announcement Wednesday.
While Endo Pharmaceuticals said it was company policy not to comment on current litigation, it did put out a statement.
"At Endo, our top priorities include patient safety and ensuring that patients with chronic pain have access to safe and effective therapeutic options. We share in the FDA's goal of appropriately supporting the needs of patients with chronic pain while preventing misuse and diversion of opioid products," the statement said.
Purdue Pharma denied the allegations in the lawsuit and said it was an "industry leader" in abuse-deterrent technology.
"While we vigorously deny the allegations in the complaint, we share the attorney general's concerns about the opioid crisis and we are committed to working collaboratively to find solutions. OxyContin accounts for less than 2% of the opioid analgesic prescription market nationally, but we are an industry leader in the development of abuse-deterrent technology, advocating for the use of prescription drug monitoring programs and supporting access to Naloxone -- all important components for combating the opioid crisis," Purdue's statement said.
Janssen Pharmaceuticals spokeswoman Jessica Castles Smith said the company recognizes that "opioid abuse is a serious public health issue. Janssen has acted appropriately, responsibly and in the best interests of patients regarding our opioid pain medications, which are FDA-approved and carry FDA-mandated warnings about the known risks of the medications on every product label."
Hawley was joined at the news conference by a mother who lost her teenage daughter to opioid addiction and a man recovering from opioid abuse.
Hawley said beyond "seeking one of the largest judgments in Missouri history," he wants to implement "anti-addiction programs and public awareness education" as well as "rehabilitation opportunities and job training."
Previous suits filed
The Missouri suit follows a filing by Ohio
suing five drug companies, accusing them of fueling the opioid crisis there by misleading doctors about the risks of addiction.
In adddition to those actions, counties and cities across the country have begun filing lawsuits against manufacturers over their roles in the drug epidemic. In Cabell County, West Virginia a complaint was filed
(PDF) earlier this month alleging that between 2007 and 2012, drug companies and distributors, including pharmacies such as Walgreen's and Rite Aid, sold nearly 40 million doses of prescription opiates such as hydrocodone and oxycodone to county pharmacies.
The county population during those years grew from just over 94,000 to just over 96,000 people. Similarly, nearby Kanawha County, West Virginia, filed a lawsuit
(PDF) at the same time alleging the drug companies sold 66 million doses of these medications during the same time period when the county population ranged from about 191,000 to 192,000 residents."
Earlier this month several state attorneys general announced an initiative to investigate what role manufacturers may have played
in contributing to the opioid epidemic.