Lawsuits filedby state attorneys general in 2016 and this year allege aconspiracy among 20 drugmakers to carve up the market and raiseprices of more than 100 drugs.

Senator Bernie Sanders and Representative Elijah Cummings areopening an investigation into generic-drug giants Mylan NV and TevaPharmaceutical Industries Ltd. on allegations of “apparentcoordinated obstruction” in failing to provide lawmakers withdetails about their pricing practices.

Sanders, an independent from Vermont who is running for theDemocratic nomination for president, and Cummings, a Democrat fromMaryland, sent letters to Teva and Mylan as well as closely heldHeritage Pharmaceuticals Inc. The letters renewed a 2014 requestfor the companies to provide documents related to charges ofgeneric-drug price-fixing.

Related: Drugmakers accused of generic-drug price fixing innew antitrust lawsuit

The two companies have been at the center of state and federalprobes into allegations that generic-drug companies coordinatedwith one another on setting prices for a range of widely usedmedications.

Lawsuits filed by state attorneys general in 2016 and this yearallege a conspiracy among 20 drugmakers to carve up the market andraise prices of more than 100 drugs including commonly prescribedantibiotics as well as medications for reducing cholesterol andcontrolling seizures. Those actions, authorities allege, costtaxpayers and patients billions of dollars. The prices of somedrugs increased by as much as 8,281% between October 2013 and April2014, according to the lawmakers’ letter made public onWednesday.

The most recent lawsuit included emails from 2014 in whichexecutives at Teva, Mylan and Heritage planned to respond tocongressional inquiries with “polite f-u” letters.

“Not only did your company’s apparent obstruction undermine ourinvestigation, but it may have caused further harm to patients andhealth care providers by delaying the discovery of evidence aboutthe companies’ price-fixing,” Sanders and Cummings wrote to thecompanies on Tuesday. They said withholding or concealinginformation in a congressional investigation is a violation offederal law.

Teva spokeswoman Kelley Dougherty said the company will“continues to cooperate fully with all investigations.”

Mylan, which recently announced plans to combine its businesswith Pfizer Inc.’s unit of older blockbuster medicines, said in astatement that it did not obstruct the 2014 congressional inquiry,and “will continue to cooperate” with investigations.

“Mylan respects Congress’s long-standing interest in drugpricing and has worked and will continue to work constructivelywith Congress to provide it with information relevant to itsinquiries,” the company said in a statement.

A representative for Pfizer declined to comment. The companieshave said they expect their deal to close in mid-2020.

A representative for Heritage couldn’t immediately be reachedfor comment.

Mylan fell as much as 8.7 percent in New York onWednesday amid a broader stock-market sell-off. Teva’s U.S.-tradedstock fell as much as 8.6 percent; the shares hit theirlowest price since 1999 last week when the company set aside $646million for legal expenses related to its role in the opioidcrisis.

Probes hit roadblocks

The renewed investigation into the drugmakers comes as a federalprobe into the generics industry has hit significant obstacles.Over the course of a multiyear Justice Department investigation,only two executives from Heritage Pharmaceuticals have beencharged. Both pleaded guilty more than two years ago.

The Justice Department will likely bring additional chargessoon, Bloomberg reported in July, citing two people familiar withthe investigation, though it’s not clear who might be charged. Bothpeople said the probe has encountered challenges, but they saidit’s no different from any other complex case. On at least some ofthe conduct that has come to light, the five-year criminal statuteof limitations is set to expire next year.

Read more: 

• Doctors call for fight against generic drug priceincreases
• Pharma execs in the hot seat on drugprices
• Drugmakers vs. Trump: What’s next for theshowdown?

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