Washington (CNN) Several Hill Democrats are calling for action in the wake of a bombshell report that found the pharmaceutical industry successfully lobbied Congress to make it easier to distribute opioids across American communities and thwart the Drug Enforcement Administration's efforts to halt the addiction crisis.

Drug companies -- including Pharmaceutical Research and Manufacturers of America, CVS Health, and the National Association of Chain Drug Stores -- lobbied for a new bill that made it "virtually impossible for the DEA to freeze suspicious narcotics shipments" from drug distributors, according to an upcoming law review article cited in the report by CBS's "60 Minutes" and The Washington Post.

In a statement issued on Monday, PhRMA, which represents biopharmaceutical research companies, said it had not been contacted by the news organizations regarding the story.

"With regards to the recent Washington Post & 60 Minutes stories, we want to be clear that PhRMA did not support or lobby in favor of the Ensuring Patient Access and Effective Drug Enforcement Act and reports that PhRMA spent $40 million lobbying this bill are unequivocally false," a statement read. "Had we been contacted by these news outlets in advance of their stories running, we would have explained our longstanding support for enhanced law enforcement efforts to fight the opioid epidemic."

A DEA whistleblower told "60 Minutes" the US government slowed down enforcement against large pharmaceutical companies just as the opioid epidemic was taking hold. He said the companies turned a blind eye as the pills flooded US communities while lawmakers passed a law to help the industry at the same time.

The sponsor of the bill was Rep. Tom Marino, R-Pennsylvania, the man President Donald Trump has named to head the Office of National Drug Control Policy. The bill was signed into law by then-President Barack Obama in April 2016.

West Virginia Sen. Joe Manchin, who serves a state heavily impacted by the opioid epidemic, called for the White House to remove Marino from consideration for the position Monday morning.

"His advocacy for this legislation demonstrates that Congressman Marino either does not fully understand the scope and devastation of this epidemic or ties to industry overrode those concerns," Manchin said in a statement. "Either option leaves him unfit to serve as the head of the ONDCP."

After the report was published on Sunday, Sen. Claire McCaskill, D-Missouri, called for the 2016 bill to be repealed.

"Media reports indicate that this law has significantly affected the government's ability to crack down on opioid distributors that are failing to meet their obligations and endangering our communities," McCaskill said in a statement released by her office. "I'll be introducing legislation that repeals this law and continue my work investigating the role pharmaceutical distributors played in fueling this public health crisis."

Both Manchin and McCaskill, however, were among the senators who allowed the bill to pass by unanimous consent in the Senate without even a vote. McCaskill's office initially told CNN later Monday that the senator had taken a leave of absence at the time to undergo breast cancer treatment, though it later clarified that the Missouri Democrat had returned to Congress at the time of the vote.

At a Rose Garden news conference on Monday, Trump said he was going to look into the report and spoke warmly of Marino.

"He was a very early supporter of mine, the great state of Pennsylvania," Trump said. "He is a great guy. I did see the report. We are going to look into the report. We are going to take it very seriously."

Trump added that he will speak to Marino and "if I think it is 1% negative to doing what we want to do, I will make a change."

A spokesman for Senate Judiciary Chairman Chuck Grassley said Marino's questionnaire has not been received yet and, therefore, a confirmation hearing hasn't been scheduled.

The bill Marino pushed called the Ensuring Patient Access and Effective Drug Enforcement Act, gained supporters from the left and right. Some of the bill's sponsors -- including Marino, Utah Republican Sen. Orrin Hatch, and Tennessee Republican Rep. Marsha Blackburn -- all work for constituencies heavily affected by the opioid epidemic, the report said. The investigation said each raised at least six figures in campaign contributions from the pharmaceutical industry: Marino got nearly $100,000, Blackburn got $120,000, and Hatch got $177,000.

CNN has not verified the details of the investigation, which was based on interviews with former DEA agents and lawyers suing the opioid industry, Federal Election Committee filings, a review of a yet-to-be-published Marquette Law Review article, and Department of Justice documents obtained through the Freedom of Information Act. "60 Minutes" and The Washington Post are suing for more documents, some of which have been pending for 18 months.

Asked by CNN to comment on the article, the DEA said it was working on "preventing reckless doctors and rogue businesses from making an already troubling problem worse. Increasingly, more and more individuals are facing criminal charges. During the same timeframe, our investigators initiated more than 10,000 cases and averaged more than 2,000 arrests per year. We will continue fighting the opioid crisis and continue to use all the tools at our disposal to combat this epidemic."

In a statement to CNN, Matt Whitlock, a spokesperson for Hatch, said that while the investigation "seeks to establish a narrative that, while perhaps fitting for a Netflix original series, simply does not reflect the actual events surrounding the drafting, negotiation, and passage" of the law. Whitlock argued that DEA and DOJ "allowed the bill to pass by unanimous consent," suggesting that the organizations agreed with the legislation. However, as the Post reported , then-Attorney General Eric Holder publicly opposed the bill.

CNN has reached out to the offices of Marino and Blackburn for comment.

Aside from campaign contributions, the Post report suggests that Marino's staff reaped benefits of a cozy relationship with the drug industry, too. Seven months after the bill's passage, his chief of staff left Capitol Hill to work for National Association of Chain Drug Stores.

The law, which was supposed to further define "imminent danger," raised the bar for evidence on the suspension orders on drug shipments.

Former DEA lawyer Jonathan Novak said the result of the bill was fewer busts, and more DEA staff "auditioning" for the pharmaceutical industry as opioid deaths and overdoses continued to climb.

"There's no denying the numbers. At the height of the opioid epidemic, inexplicably, [suspensions] slowed down. ... Some of the best and brightest, DEA attorneys, are on the other side and know all the weak points," he told " 60 Minutes ." "Their fingerprints are all on the memos, and the policy and emails going out where you see this concoction of what they might argue in the future."

According to internal emails obtained by "60 Minutes" and the Post under the Freedom of Information Act, Justice ,Department officials said the bill was written by Liden Barber, a former DEA associate chief counsel who left to work for the drug industry in 2011. Barber declined requests to be interviewed for the article.

The whistleblower, former DEA agent Joe Rannazzisi, said he was forced out of the agency in 2015 after being outspoken about the threat of the pharmaceutical industry during his tenure heading the office of diversion control. Marino and Blackburn demanded an investigation into Rannazzisi after he allegedly said the bill's sponsors were aiding criminals, a claim Rannazzisi denied in the report.

This story has been updated to reflect additional comment from McCaskill's office.