A cancer drug that costs $129,000 a year—more than three times the price in Japan and Sweden and four times the cost in Canada—has become the latest subject of public and congressional scrutiny, as 12 representatives joined nonprofits to call for a public hearing on the drug’s price.

Xtandi, a prostate cancer drug co-licenced by Japan’s Astellas Pharma Inc. 4503, +0.46% and Medivation Inc. US:MDVN, was developed at a U.S. university with grants funded by taxpayer dollars. That gives the federal government the right to revoke the patent if the terms are unreasonable, said the letter, dated Monday.

“We do not think that charging U.S. residents more than anyone else in the world meets the obligation to make the invention available to U.S. residents on reasonable terms,” said the letter, which had Sen. and presidential candidate Bernie Sanders, Sen. Elizabeth Warren and Rep. Elijah Cummings among its signatories.

Astellas said that the $129,000 price tag “fails to reflect what payers or patients actually pay for the medicine.”

Of the 20,000 patients on Xtandi last year, 81% of the privately insured paid $300 or less out of pocket per year and 79% of patients on Medicare had no out of pocket costs a month, the company said in a written statement, also noting its access program made the drug free for more than 2,000 advanced prostate cancer patients last year.

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The nonprofits Knowledge Ecology International and the Union for Affordable Cancer Treatment first petitioned the National Institutes of Health for such a hearing in a mid-January letter, asking top brass at the Department of Health and Human Services, the National Institutes of Health and the Department of Defense to revoke Medivation’s exclusive patent rights and allow other licenses.

The NIH has been petitioning for such a move, termed “march-in rights” and spelled out in the 1980 Bayh-Dole Act, in prior years.

In 2004, the agency granted a hearing on the pricing of an antiretroviral medication put out by Abbott Laboratories ABT, +0.18% ABT, +0.18% but it decided “the issue of drug pricing is one that would be more appropriately addressed by Congress, as it considers these matters in a larger context.”

However, Abbott did lower the drug’s price for programs such as Medicaid and improve its financial assistance programs in the hearing’s wake, the Monday letter noted.

Medivation wrote in an emailed statement that the bid for march-in rights for Xtandi “does not meet the criteria laid out in the Bayh-Dole Act nor is it an appropriate way to address perceived pricing disparities in different health care systems.”

“Furthermore, we believe taking measures such as exercising ‘march-in’ rights would stifle the kind of innovation and collaborations with public institutions which have resulted in innovative medicines, such as Xtandi, that have made meaningful clinical improvements in the lives of patients,” the company said.

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Several other advocacy organizations joined KEI and UACT’s request in late March, with the congressional letter following a week later.

“Price can be a clear barrier to access for consumers, and despite this law being in place for over 35 years, the NIH has never used this broad and powerful authority to protect consumers from excessive prescription drug prices,” the congressional letter said.

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In the ferocious debate about whether drug prices are too high, pharmaceutical companies often say that the cost finances research and development of new, lifesaving drugs.

But Medivation can’t invoke that argument in this case, said KEI founder and director Jamie Love.

“The system’s working great for everyone but the taxpayers and the patients,” Love said.

The $129,000 cost impedes patient access, he said, “but it also affects people even when the patient gets access, because the price is too high.”

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An earlier version of this article incorrectly described Medivation as a unit of Astellas. It has been corrected.