Pharmaceutical Research and Manufacturers of America has increased membership dues by 50 percent to raise additional money as the group prepares to wage an expensive political and PR campaign against lawmakers who want to rein in rising drug prices, Politico reported Tuesday.

The dues increase will generate an additional $100 million for the association, swelling annual revenue to more than $300 million, according to the newspaper, which cited anonymous sources. PhRMA is preparing to spend potentially hundreds of millions of dollars on advertising against politicians who have been critical of price increases for prescription medications.

Drug prices have become a political liability for the pharmaceutical industry as the result of two recent controversies. The first was the decision by Turing Pharmaceuticals last year to raise the price of a potentially life-saving medication by more than 5,000 percent after acquiring the rights to manufacture the drug. More recently, drug manufacturer Mylan has faced harsh criticism for increasing the price of EpiPens to more than $600 for a pack of two of the devices.

Both Hillary Clinton and Donald Trump have pledged to take steps to prevent future drug price hikes if elected president. The issue also has been the subject of high-profile hearings on Capitol Hill, with polls showing the majority of voters want lawmakers to do something about drug prices.

PhRMA isn't planning to launch a campaign until after the election, but an upcoming ballot issue in California could prove a test case for what is to come. Proposition 61 would prevent state agencies from purchasing prescription medications at rates higher than the U.S. Department of Veterans Affairs pays for the same drugs.

Supports of Prop. 61 believe the proposed law will hold down drug prices. PhRMA has raised nearly $109 million from pharmaceutical companies to oppose the measure, according to state campaign finance records. So far the association's strategy doesn't appear to be working, with polls indicating California voters are likely to pass Prop. 61 on Election Day. http://politi.co/2dKA2eB

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