A newly released report says the Food and Drug Administration may have failed to set strict enough standards and follow-through for training doctors about the risks associated with opioids. Researchers say lack of oversight and training problems happened while the opioid crisis killed tens of thousands of people a year.

The rules were part of what's called a Risk Evaluation and Mitigation Strategy, or REMS, which required manufacturers of long-acting and addictive opioids like OxyContin to pay for training for doctors prescribing the drugs, and to monitor and report back on how well that training was working. But in the study published in JAMA Internal Medicine, researchers at Johns Hopkins University found that didn't happen.

The report said long-acting or "extended-release" opioids such as oxycodone and morphine "were associated with greater risk of addiction, unintentional overdose and death than their immediate-release counterparts."

So in 2012, the FDA set up rules requiring painkiller manufacturers to deliver "continuing education" to doctors and "develop medication guides to inform patients about risks" as well as monitor and report on "patient access to drugs and safety."

But problem was that the FDA let the pharmaceutical companies themselves create the curriculum, experts say.

"One of the problems is that education is voluntary. The other problem was simply the content," said Dr. Andrew Kolodny, medical director for Opioid Policy Research at Brandis University. "It was a curriculum designed by the drug makers, a curriculum that didn't really discourage aggressive prescribing."

Researchers found in their review of thousands of FDA documents that the agency failed to follow up on problems with the program and reportedly never insisted on changes to address those problems.

"The consequences were that at a time when the CDC and other public health groups across the country were trying to get doctors to prescribe more cautiously, the FDA had a training program for doctors that was encouraging more aggressive prescribing. This was making it more difficult to tackle the opioid crisis," Kolodny said.

After this story ran on "CBS This Morning," an FDA spokesperson reached out to dispute Kolodny. She wrote that "the REMS program was an educational component, limited by lack of a mandatory federal requirement that prescribers take the training." The spokesperson also said "there is no evidence that at any point (the program) contributed to the crisis."

In an earlier statement to CBS News, the FDA said: "The opioid tragedy is a defining public health crisis. While we're grateful to see overdose deaths begin to decline thanks to effective federal and local community partnership, we know there's more work to do be done. The REMS program is one element in a broader national effort to stem the tide of addiction in communities."

Jennifer Wysong, who became addicted to opioids after having a C-section, said her addiction "basically controlled my life." It eventually landed her behind bars.

"Every single day when I woke up, my main focus was wake up, and figure out a way to get what I needed to just get through the day," she said. "I didn't care who I hurt or you know what I had to do to get it."

Her story is not uncommon. The Centers for Disease Control and Prevention (CDC) said in 2017, opioids were involved in more than 65% of all drug overdose deaths.

Wysong is now clean and sober but wonders if REMS program could have made a difference.

"I think that if they could know what we know now back then… things might have been a little bit different," Wysong said.

The CDC does lay out guidelines for proper opioid prescription. Those include evaluating the need for paid medications, proper selection of the right drug, and assessing the risk of addiction and explaining those risks to the patient. But it wasn't until 2017 that the FDA began requiring safety programs for all opioid painkillers, not just the long-acting ones.