FDA Greenlights Eli Lilly’s Alzheimer’s Drug Donanemab

On Tuesday, the Food and Drug Administration (FDA) granted approval for Eli Lilly’s Alzheimer’s drug, donanemab, marking a significant milestone in the treatment of the disease. The approval comes after extensive clinical trials demonstrated that donanemab could considerably slow cognitive decline, overcoming multiple delays in bringing this experimental therapy to market.

Eli Lilly’s donanemab, branded as Kisunla, is now approved as a monthly injection. This follows an 18-month clinical trial that revealed substantial results in slowing both cognitive and functional decline among Alzheimer’s patients. The trial, involving over 1,700 participants, was designed to assess the drug’s efficacy in both early and advanced stages of the disease. Results showed that patients treated with donanemab experienced a 39% reduced risk of worsening disease compared to those given a placebo.

The trial results also indicated that 17% of participants discontinued donanemab treatment after six months, while 47% stopped within a year, and 69% ceased after 18 months. Remarkably, those who discontinued the drug continued to show a slowdown in cognitive decline, suggesting lasting benefits beyond the treatment period.

The cost of Kisunla is substantial: a 12-month treatment will cost $32,000, a six-month regimen will exceed $12,500, and an 18-month supply will amount to nearly $49,000, according to Eli Lilly.

Donanemab is only the second Alzheimer’s drug to receive FDA approval, following Biogen and Eisai’s lecanemab, marketed as Leqembi, which was approved last year. Like donanemab, lecanemab targets amyloid proteins in the brain, which are linked to Alzheimer’s disease. However, lecanemab requires biweekly administration and continues treatment even after sufficient amyloid has been cleared. The annual out-of-pocket cost for lecanemab is about $26,000. Anne White, Eli Lilly’s executive vice president, explained that the higher cost of donanemab reflects its anticipated benefit of allowing patients to stop treatment after removing enough amyloid, potentially lowering long-term expenses for patients.

Eli Lilly’s donanemab was initially subjected to scrutiny after its late-stage clinical data was released last year. Medical organizations and experts urged for its approval, but the FDA postponed its decision in March to conduct a more thorough review of the drug’s safety and efficacy. The delay was fueled by concerns that the drug’s benefits were not statistically significant and that removing amyloid proteins might not effectively slow cognitive decline. Additionally, there were apprehensions about potential risks, such as brain swelling and bleeding, following reports of three trial participants’ deaths due to side effects.

On the same day as the FDA’s approval, Eli Lilly and Novo Nordisk saw their stock prices fall by up to 4% in response to an op-ed from President Joe Biden and Senator Bernie Sanders. The op-ed criticized the high prices of their weight loss drugs, Ozempic and Mounjaro, compared to international pricing. Biden and Sanders condemned the companies for what they deemed “unconscionably high prices” in the U.S., contrasting them with lower costs in other countries. Sanders, in particular, has been vocal about Novo Nordisk’s pricing, pointing to a Yale University study suggesting that the manufacturing cost of Ozempic and Wegovy injection pens could be as low as $5 per month, while the retail price in the U.S. is $1,000 per month, compared to $300 in Canada.