Pfizer, the world’s second-largest drug maker, has agreed to adhere to strict standards for marketing and promoting prescription opioids to treat common chronic pain conditions, such as arthritis and back pain.

The company made the agreement with the city of Chicago, which sued five other opioid manufacturers over alleged misleading marketing of opioids, The Washington Post reports. Pfizer was not named in the lawsuit. The company has been helping the city with its investigation and lawsuit, the city said in a news release.

The company said it will disclose in its promotional material that opioid painkillers carry serious risk of addiction, even when they are used correctly. Pfizer pledged not to promote opioids for unapproved, “off-label” uses, such as long-term back pain, and said it will acknowledge there is no good research on the drugs’ effectiveness beyond 12 weeks.

Adriane Fugh-Berman, Associate Professor of Pharmacology and Physiology at Georgetown University School of Medicine, said she thinks the agreement will have limited value.

“Maybe it’s a first step, but I think counting on pharmaceutical companies to get us out of this opioid mess is not likely to be successful,” said Fugh-Berman, who is also Director of Pharmed Out, which advocates rational prescribing practices.

Aggressive marketing by Purdue Pharma, which makes OxyContin, has been widely blamed for the quick growth of opioid painkiller use, the article notes.