WASHINGTON -- Celgene Corp. under Bob Hugin, the Republican running for U.S. Senate in New Jersey, raised U.S. prices by 20 percent for its Revlimid cancer drug while cutting them by 45 percent in Russia last year, documents show.

The disparity in drug prices is not unusual, experts said, but the pricing practices could provide another line of attack for U.S. Sen. Robert Menendez, D-N.J., who has found fertile ground plowing through Hugin's tenure at Celgene.

Celgene under Hugin spent a record amount of money to help defeat legislation that would have made it easier for generlc companies to get drug samples, and President Donald Trump's Food and Drug Administration singled out the company for refusing to make those samples available to competitors.

Menendez has used the high cost of Revlimid in the U.S. -- the out of pocket costs for Medicare Part D enrollees was $11,538 in 2016, before last year's price hikes, according to the Kaiser Family Foundation -- to deflect the attacks on his own ethical problems that have been a theme of Hugin's campaign

"It's clear that Bob Hugin is more than happy to rip off American cancer patients to line his own pockets, but when he gets a little pressure from Vladimir Putin, like Donald Trump, he caves," Menendez campaign spokesman Steven Sandberg said. "If he can cut the price in Russia, then he can cut the price here at home. He just won't.''

The Hugin campaign's reply was blunt.

"Putin is a thug. Menendez is a crook and a liar," Hugin spokeswoman Megan Piwowar said. "And any attempt to link Marine Corps veteran Bob Hugin to Vladimir Putin doesn't even merit a response."

Integrity NJ, the pro-Hugin super political action committee whose principals have ties to Gov. Chris Christie, has begun airing commercials calling Menendez "shamelessly corrupt" and highlighting his 2015 indictment on federal corruption charges.

Menendez's trial ended with a deadlocked jury, and the Justice Department declined to try him again after a federal judge acquitted him of some of the charges. He later was "severely admonished" by the Senate Ethics Committee for accepting gifts from Dr. Salomon Melgen, a friend and campaign donor, while intervening with federal agencies on his behalf.

Celgene's pricing of the cancer drug Revlimid has come under attack by Trump and advocacy groups.

The price of a 21-tablet supply of Revlimid in 25 mg dose was $14,529 in the United States, according to a report by Patients for Affordable Drugs Action, a super political action committee opposing Hugin.

That same product cost $4,175 in Russia after the price reduction, according to the Russian Federation's Federal Antimonopoly Service.

Celgene spokesman Greg Geissman said there was nothing unusual about the practice of adjusting prices in different countries.

"Actions like these are a regular occurrence in many countries outside of the United States where the health authorities assess overall health care spending, including medicines, and impose price actions on the manufacturers," Geissman said.

The Russian Federal Antimonopoly Service reported in September 2017 that Celgene agreed to reduce the price of Revlimid by 45 percent following negotiations after suggesting that "manufacturers of appropriate medicines voluntarily reduce the inflated prices."

While Russia was able to obtain lower prices for Revlimid, its cost continued to rise in the U.S. even as Trump railed against high drug prices.

Last year, the U.S. price of Revlimid was raised three times, totaling around 20 percent, according to Yatin Suneja, a SunTrust Robinson Humphrey biotech analyst.

The price for a 28-count bottle rose to $18,546 in October 2017 from $15,483 in August 2016. It went up another 5 percent, to $19,473, last month.

Trump invited Pam Holt, an Indiana woman who said she had to refinance her house to afford Revlimid, to the White House in May when he announced efforts to reduce drug costs.

FDA Commissioner Scott Gottlieb then reported that the agency had received more requests from generic companies for samples of Revlimid than any other drug but one.

"Celgene is able to continue raising prices because it has managed to keep a generic off-market here and other countries negotiate more aggressively with these drug companies than we do," said David Mitchell, who heads Patients for Affordable Drugs, which supports actions to lower drug prices, and founder of the anti-Hugin super PAC.

Celgene's Geissman said drug prices reflect their value to patients and help fund research into new products. Celgene's research budget is equal to 45.5 percent of sales, one of the highest percentages of any large company in any industry, Geissman said.

In addition, on a per person basis, Russia's gross domestic product is much lower than that in the U.S., he said.

"To achieve our goal of access to our innovative medicines, one of Celgene's pricing principles is the concept of flexibility," Geissman said. "Celgene believes in providing broad global access to our therapies to patients from counties of differing economic circumstances."

Jonathan D. Salant may be reached at jsalant@njadvancemedia.com. Follow him on Twitter @JDSalant or on Facebook. Find NJ.com Politics on Facebook.