Will Medicare Part B premiums go up again in 2024?

Next year’s Medicare Part B premiums are expected to be announced soon and there is speculation that coverage of another pricey new Alzheimer’s medication could cause monthly costs to go up, echoing what occurred in 2022.

Leqembi received full approval from the Food and Drug Administration (FDA) in July, becoming the second drug of its kind to hit the market after Aduhelm. The drug comes with an annual cost of $26,500.

While only approved for patients with mild cognitive impairment or mild dementia who are also confirmed to have a brain plaque called amyloid, the pharmaceutical industry expects Leqembi to be popular.

While the medication is not a cure for Alzheimer’s disease, Leqembi is the first drug to demonstrate clinical benefits to patients by slowing down the progression of the disease. This is accomplished by targeting and reducing amyloid plaque in the brain, the buildup of which is linked to cognitive decline.

Leqembi’s manufacturer Eisai estimates about 100,000 people will be eligible to take the drug in the U.S. by the third year of its availability, and Medicare’s coverage of the drug should open up access to it. But some have posited that 100,000 in three years could be a conservative estimate.

Tricia Neuman, KFF senior vice president and executive director for its program on Medicare policy, noted the exact uptake of Alzheimer’s medications among Medicare beneficiaries isn’t known.

The true number of patients who could benefit from Leqembi is unclear because it’s difficult to accurately estimate how many people with Alzheimer’s disease have mild cases.

“The number and proportion of older adults who have [Mild Cognitive Impairment] due to Alzheimer’s disease is currently difficult to estimate because they require population-based prevalence measures of MCI and Alzheimer’s biomarkers, and this line of research is in its infancy,” the Alzheimer’s Association noted in its 2023 Alzheimer’s Disease Facts and Figures report. 

The criteria for MCI is also different across different studies, further complicating estimates. The Alzheimer’s Association observed that some studies estimate 17 percent of people 65 and older have MCI while others estimate anywhere between 8 and 11 percent.

As KFF noted in a report earlier this year, an uptake of 100,000 would represent 1.5 percent of U.S. adults with Alzheimer’s — an estimated 6.5 million people — and even that degree of use would make Leqembi the third most costly drug to be covered by Medicare Part B.

In 2023, the monthly premium of Medicare Part B fell for the first time in 10 years, going from $170.10 a month to $164.90.

This drop was preceded by a major premium hike in 2022 — 15 percent — that was attributed to Medicare’s coverage of the new Alzheimer’s drug Aduhelm. The Department of Health and Human Services (HHS) would later determine that the increase due to Aduhlem was overestimated, leading to the premium being lowered.

The Medicare Board of Trustees estimated the Medicare Part B premium for 2024 could be $174.80 in its annual report released this year, marking a 6 percent increase. This change would not be among the highest jumps seen in recent years. Neuman noted the estimate, put out six months ago, could change due to numerous factors separate from Medicare’s coverage of Leqembi.

“It's difficult to know exactly what the Part B premium will be in 2024 or how it will be influenced by any given drug, including Leqembi,” said Neuman.

“The Part B premium is influenced by a number of factors, like growth in spending for other services like physician services and hospital outpatient services and the drugs that are administered by physicians,” she added.

When reached for comment on when the final Medicare Part B premium for 2024 will be announced, the Centers for Medicare and Medicaid (CMS) said it expects to release that information some time in the fall.