Health officials said Friday that a new Alzheimer's drug is responsible for about half the reason why Medicare's "Part B" outpatient premium will have one of the most significant increases ever in 2022, according to The Associated Press.

The other half of the premium increase is due to the natural growth of the program and adjustments made by Congress last year as the coronavirus pandemic hit.

"The increase in the Part B premium for 2022 is continued evidence that rising drug costs threaten the affordability and sustainability of the Medicare program," Centers for Medicare & Medicaid Services chief Chiquita Brooks-LaSure said in a statement.

The new Part B premium will be $170.10 a month for 2022, a jump of $21.60 and the most considerable increase ever. The 2021 Medicare Trustees report published in August had projected a much smaller increase of $10 from the current $148.50.

One representative is sounding the alarm on the premium hike.

"Today's announcement ... confirms the need for Congress to finally give Medicare the ability to negotiate lower prescription drug costs," Rep. Frank Pallone, D-N.J., said in a press release. "We simply cannot wait any longer to provide real relief to seniors."

Aduhelm, the Alzheimer's medication causing the hike, is priced at $56,000 per year - but a nonprofit think tank pegged Aduhelm's actual value between $3,000 and $8,400 per year based on its unproven benefits, AP said.

The Food and Drug Administration (FDA) approved the drug in an accelerated manner this June, bypassing an independent panel of outside experts, according to CNBC.

Biogen CEO Michel Vounatsos defended Aduhelm's pricing to the network, saying it will allow the company to further invest in its pipeline of medicines for other diseases.

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