The CEO of pharmaceutical developer Biogen said that a list price of $56,000 for a new drug to treat Alzheimer’s is a “fair” price, citing the cost of development over two decades, CNBC reports.

During the network’s “Powerlunch” program, CEO Michel Vounatsos said the company’s FDA-approved Alzheimer’s disease drug aducanumab, brand-named Aduhelm, the first Alzheimer’s drug in nearly 20 years to be approved by the FDA, is working toward approval by Medicare and insurance companies’ formularies.

Currently, an estimated six million Americans suffer from some degree of Alzheimer’s.  Aducanumab was approved for use in early-phase patients, suffering from mild cognitive loss, not dementia. 

The support for approval was not universal, nor was the approval of the distribution of the drug.  Biogen will have to go through what’s known as a “post-approval Stage 4” trial, meaning that patients receiving the drug will be tracked and their conditions reported.

“We have to really temper expectations and explain to people that this drug is meant for the earliest symptomatic phases,” Dr. Richard Isaacson, director of the Alzheimer’s Prevention Clinic at Weill Cornell Medicine and NewYork-Presbyterian in New York, told CNN. “It pains me to say this but if I have a severe Alzheimer’s patient that can no longer speak or interact much with others and their family member is begging me to give them this drug, I won’t be able to do it.”

Biogen says patients should receive doses of aducanumab every four weeks, putting the cost per injection at $4,312, amounting to a $56,000 annual tab for patients or their insurance carriers.  The independent Institute for Clinical and Economic Review, a watchdog group that reviews drug prices, said that a fair market price for the drug should be $2,560 to $8,290 per year.  It also notes “the evidence is insufficient to conclude that the clinical benefits of aducanumab outweigh its harms or, indeed, that it reduces progression [of Alzheimer’s disease].”

“Biogen and Eisai [Biogen’s Japanese partner in development] are committed to providing access to ADUHELM for patients across a spectrum of financial situations,” the company noted in its announcement. “For qualified, commercially insured ADUHELM patients, co-pay and infusion cost assistance programs may reduce out-of-pocket costs to as low as $0. Patients who are covered by Medicare through a Medicare Advantage plan have a maximum annual out-of-pocket cap.”