On Monday, the CDC released its draft guidelines for opioid prescribing, but now says the recommendations will be subject to further review, which will also incorporate public comments, resulting in the delay of the release.

The delay was first signaled yesterday when the CDC unexpectedly disclosed that public comments on its proposal would be accepted through Jan. 13. However, the agency will also tap the National Center for Injury Prevention and Control’s Board of Scientific Counselors, a federal advisory committee, to review the guidelines and public comments. Its first meeting is scheduled for Jan. 7.

The postponement follows complaints from representatives of other federal agencies and consumer advocacy groups that the CDC guidelines were based on weak evidence and would unfairly restrict some patients from obtaining needed pain relief. The agency was also chastised for using a “secretive” process to formulate the guidelines, which some critics argued had violated federal law.

The guidelines were assembled earlier this year in response to a long-running epidemic of opioid abuse and misuse. Every day, 52 Americans die from overdoses of opioid painkillers. And so, the CDC convened a group of outside experts to draft guidelines for primary care physicians, since family doctors and internists write the vast majority of prescriptions for these drugs.

The CDC guidelines call on doctors to prescribe opioids only after other therapies have failed. The proposal also suggests physicians start their patients on short-acting opioids instead of extended-release, long-acting opioids, and initially prescribe the lowest possible effective dosage. The overall theme is to bolster physician awareness of abuse problems and encourage greater monitoring.

But critics charge the guidelines will be far too restrictive, making it difficult for some patients to be treated with the most effective options. There is also concern that the guidelines, which are not binding, will be widely adopted by state legislatures and government agencies.

These objections began percolating after the CDC disclosed the guidelines last fall. Earlier this month, the National Institutes of Health’s Interagency Pain Research Coordinating Committee met and decided to file an objection to the CDC. In particular, many of the participants expressed concern that the CDC relied on what was termed weak evidence for some of its recommendations.

“It flies in the face of science,” Myra Christopher of the Center for Practical Bioethics, a nonprofit patient advocacy group, said at the meeting. The organization, by the way, is one of at least three patient groups that participated in the meeting and receive industry funding. Meanwhile, the Center for Practical Bioethics receives at least some of its funding from pharmaceutical firms, including Purdue Pharma, a spokesperson from the drug maker said. The Center for Practical Bioethics did not respond to questions.

“CDC’s plan to issue its guideline in January was thwarted by a well-organized, industry-funded effort,” said Dr. Andrew Kolodny, chief medical officer at Phoenix House, a nonprofit that runs alcohol and drug abuse treatment and prevention programs, and the head of Physicians for Responsible Opioid Prescribing, an education and advocacy group. A PROP member helped draft the guidelines.

Separately, a member of the CDC’s Core Expert Group, which helped the agency draft the guidelines, explained that the agency’s decision to rely on weak evidence reflected a stark reality. There is a lack of sufficient evidence to properly evaluate long-term opioid use or compare the drugs with other options, according to this group member.

Nonetheless, officials from other federal agencies also complained. The level of evidence cited to support the guidelines “is low to very low and that’s a problem,” said Sharon Hertz, who heads the FDA Division of Anesthesia, Analgesia and Addiction Products. And Richard Ricciardi, a health scientist at the Agency for Healthcare Research and Quality, called this “an embarrassment to the government.”

A CDC spokeswoman noted that other federal agencies were “a part of the review process and cleared the guidelines.” Nonetheless, the remarks by Hertz, in particular, were a reminder that the FDA and CDC are sometimes at odds over balancing pain relief and reducing abuse. The FDA, for instance, this summer approved a long-acting version of OxyContin for children as young as 11 years old.

Meanwhile, the CDC delay apparently reflects a desire to comply with the Federal Advisory Committee Act, which governs how expert groups are formed to provide official advice. The Washington Legal Foundation, a nonprofit that has often sided with the pharmaceutical industry in marketing matters, last month wrote the CDC to argue the agency violated the law.

The CDC is “certainly moving in right direction now,” said Richard Samp, the WLF’s chief counsel.