(Reuters) -Drugmaker AstraZeneca said on Monday it would cap out-of-pocket costs for its inhaled respiratory products at $35 per month in the United States from June, following a similar move by rival Boehringer Ingelheim earlier in the month.

High drug prices in the United States have been the subject of growing political scrutiny for years.

Senator Bernie Sanders and other lawmakers in January criticized the top four manufacturers of inhalers sold in the U.S. — AstraZeneca, Boehringer, Teva Pharmaceuticals and GSK — over high prices.

They had also launched an investigation into the prices at which inhalers for asthma and chronic obstructive pulmonary disease were sold in the U.S. versus other countries.

UK-based AstraZeneca’s cap would apply to all of its respiratory products, including inhalers such as Airsupra, Bevespi Aerosphere and Breztri Aerosphere, and would be applicable for patients who are uninsured or underinsured.

“This is a very positive step which will help save Americans thousands of dollars a year on the inhalers,” Sanders said on Monday about AstraZeneca’s decision.

The senator also urged Teva and GSK to take similar action.

“We remain committed to working with Senator Sanders and the HELP Committee to provide greater transparency into healthcare costs in the United States,” GSK said.

Teva did not immediately respond to a Reuters request for comment.

Breztri Aerosphere costs $645 in the U.S. but $49 in the UK, according to a letter by Sanders and other lawmakers sent to the four companies earlier this year.

AstraZeneca CEO Pascal Soriot said the company remains dedicated to addressing the need for affordability, but added that it is “critical that Congress bring together key stakeholders to help reform the healthcare system so patients can afford the medicines they need”.

Boehringer had also said it would cap out-of-pocket costs for its inhaler products for chronic lung disease and asthma to $35 per month, starting June 1.

Last year, Sanofi and Eli Lilly — the two major insulin makers — had also announced that they would cap insulin prices at $35 a month.

(Reporting by Puyaan Singh in Bengaluru; Editing by Shilpi Majumdar)

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