Last Updated Jul 6, 2016 5:12 PM EDT
Pfizer (PFE), the world's second-biggest drug company, will now detail the risk of addiction to opioids.
The painkillers, heavily marketed by pharmaceutical firms in recent years as a treatment for chronic conditions, are blamed for tens of thousands of fatal overdoses and for helping fuel a heroin epidemic in Chicago and other parts of the country.
The policy was disclosed Wednesday in Chicago, a city that is suing five drug manufacturers for allegedly misleading consumers and physicians about the risks of opioids.
"This landmark agreement is a big step in the right direction to help protect and educate the public about the true risks and benefits of highly potent and highly addictive painkillers," Chicago Mayor Rahm Emanuel said in a news release. "Pfizer's cooperation is proof that companies can act responsibly."
Among other steps, Pfizer agreed to disclose the risk of addiction to opioids, even when used as directed, and acknowledge that using painkillers for longer than three months has not been adequately studied, even though they're often prescribed for chronic pain.
Pfizer confirmed the accord, saying in an email that it would "continue working with various stakeholders to address this important public health concern."
Adriane Fugh-Berman, an associate professor of pharmacology and physiology at Georgetown University School of Medicine, finds the agreement puzzling.
"It's rather strange. It seems to say that Pfizer is promising to obey the law and abide by the accreditation council and abide by its own policy," said Fugh-Berman, also director of Pharmed Out, a Georgetown University Medical Center project that advocates evidence-based prescribing and educates health care professionals about pharmaceutical marketing practices.
"We should not be counting on pharmaceutical companies to educate prescribers or consumers about drugs," she said.
Neha Wadhwa, a Pfizer spokeswoman, concurred that the city's announcement did not mark a change in the company's practices. "What's different is it's formalizing what we do. It's an important issue to address," said Wadhwa, who added that Pfizer volunteered to provide Chicago with an annual report on its marketing practices.
The agreement comes two years after Chicago sued a handful of pharmaceutical manufacturers, excluding Pfizer, over the drugs used for back pain, arthritis and other long-term conditions.
"Pfizer was not named as a defendant because the city's purchases of its opioids were miniscule," Bill McCaffrey, a spokesperson for the Chicago Department of Law, said. "In addition, Pfizer cooperated fully with our pre-suit investigation."
"We filed and continue to pursue our legal action against Purdue Pharma and other drug companies to stop these companies from deceptively and unlawfully marketing opioids and to hold these companies responsible for the harm their deception has caused," Chicago Corporation Counsel Stephen Patton said in the release.
Pfizer actively promotes just one opioid painkiller, Embeda, part of an "other" category of drugs that netted the company $171 million worldwide, according to a first-quarter financial filing.
Conversely, Purdue's OxyContin generated $3.1 billion in revenue in 2010. Still, OxyContin last year made up only 2 percent of the opioid analgesic market, according to the company.
Purdue Pharma, which declined comment on the development or the ongoing litigation, has been fingered as a primary culprit in the widespread use of painkillers across the country. The company in 2007 pleaded guilty to criminal charges of misleading doctors, regulators and the public about opioids with early claims that the long-acting formulation reduced the risk of abuse.
While a relatively tiny portion of Pfizer's business, one analyst, Fitch's Robert Kirby, applauded it for being part of "a discussion over a very significant issue in America." The company is also among those looking to develop "other drugs with less potential for abuse," he added.
Pfizer is among the companies developing a generic version of OxyContin in what's called an "abuse deterrent" formulation, Fugh-Berman noted. "It's a little harder to turn into an injectable drug, so theoretically it has less street value."
Almost 165,000 people have died from overdosing on prescription narcotics in the last 16 years, according to the Centers for Disease Control and Prevention. The government estimates 2.1 million Americans are addicted to prescription painkillers.
Chicago said the city's health insurance plan has reimbursed claims for approximately $12.3 million on the painkillers between 2008 and 2015. It estimated that visits to Chicago emergency rooms due to the misuse and abuse of prescription painkillers jumped 65 percent between 2004 and 2011. In 2015, there were 84 fatal overdoses in Chicago due to prescription opioid painkillers.