Eisai Alzheimer’s Drug Gets Full US Approval, Widening Access to the Therapy

Eisai Co.’s breakthrough Alzheimer’s disease drug Leqembi gained full approval in the US. Yet, testing requirements and side effect warnings that may limit its use sent the company’s shares sliding.

(Bloomberg) — Eisai Co.’s breakthrough Alzheimer’s disease drug Leqembi gained full approval in the US. Yet, testing requirements and side effect warnings that may limit its use sent the company’s shares sliding.

The Food and Drug Administration decision marks a milestone, as Leqembi is the first drug shown to slow progression of the mind-robbing disease that afflicts some 6 million Americans. While the drug developed with Biogen Inc. was granted expedited authorization in January, the traditional approval was expected to spur greater insurance coverage of the medicine that costs $26,500 a year. 

It came with unexpected restrictions, however. MRI scans are required to monitor for early signs of side effects and the label includes a stringent black box warning about the danger of swelling and bleeding in the brain called ARIA. Doctors must closely monitor patients and detail their response in a Centers for Medicare & Medicaid Services registry every six months for the first two years. 

Eisai shares closed 4.7% lower in Tokyo as investors assessed the potential impact of the requirements. Biogen shares were halted in late trading on Thursday prior to the release of the decision. 

“Leqembi’s approval is a significant milestone,” said Evan Seigerman, a managing director at BMO Capital Markets Corp., in a note. “While enrolling in the CMS registry is unlikely to deter many patients, it could be a rate limiting activity, at least at launch.”

Why New Alzheimer’s Drugs Raise Hopes, But Modestly: QuickTake

Full approval also allows the companies to avoid the hurdles that plagued their earlier medicine, Aduhelm, which struggled to get insurance coverage and led to scant access for patients, he said. It was eventually abandoned.  

Patients with a genetic mutation called APOE4 are at even higher risk of complications, which are usually asymptomatic but in rare cases can become life-threatening. 

What Bloomberg Intelligence Says… 

Language in the product label adds another screening requirement that could add to adoption headwinds. A new boxed warning notes that patients must undergo ApoE gene testing to assess the risk of brain swelling (ARIA). We expect this, along with a CMS registry data requirement and the need for amyloid detection via brain scan or lumber puncture, to contribute to a slow rollout. 

— Marc Engelsgjerd

To read the full note, click here

The drug, also called lecanemab, is among the most potent of a new generation of antibodies that help clear amyloid, a toxic protein that slowly builds up in the brains of Alzheimer’s patients. Last fall, it became the first drug to clearly slow the disease in a large trial. Patients who received it declined at a 27% slower rate over 18 months than those given a sham treatment.

Eisai says the warning will apply to the entire class of drugs that Leqembi belongs to and is intended to raise awareness about side effects. The genetic tests shouldn’t have a significant impact on the number of people who get treatment, Chief Executive Officer Haruo Naito said. 

“We understand that the incidence of ARIA with lecanemab is low,” Naito said at a briefing in Tokyo on Friday. “The genetic test has already been used in quite a few cases since we won the accelerated approval but we aren’t seeing a fall in usage. It shouldn’t affect patients financially and we don’t expect it to have a significant impact of the number of people receiving the drug.” 

Prescribers Ready

About 1,200 neurologists are estimated to be ready to prescribe Leqembi and the number is expected to increase, Eisai said. Health providers at more than 700 infusion centers have been trained to administer it, according to the company. 

Eisai did a good job articulating why it thinks the enhanced warnings won’t impede adoption, which boosted shares in the afternoon, said Stephen Barker, an analyst at Jefferies, in a note to clients. The only constraints are the high cost of PET scans and the requirement for regular MRI scans, which are likely to slow the pace of adoption, he said. 

Read more: How a Japanese Drugmaker Clinched Win Over Alzheimer’s

Researchers have debated for decades about the degree to which amyloid contributes to Alzheimer’s, as numerous drugs that target the abnormal deposits failed in trials or showed ambiguous results. While far from a cure, Leqembi showed that removing amyloid could have a measurable effect on disease progression over long periods of time.

The Alzheimer’s Association, which pushed heavily for Leqembi’s approval and insurance coverage, called it the first treatment that “changes the underlying course of the disease.” It will help people at early stages maintain their independence for longer, said Joanne Pike, the advocacy group’s chief executive officer.  

Scant Use

Few patients have received Leqembi since its accelerated clearance in January because Medicare, the US government’s insurance program for the elderly, ruled against paying for amyloid-lowering drugs that weren’t fully approved based on a documented clinical benefit. In a statement, the Centers for Medicare & Medicaid Services confirmed it will now cover the drug.

“With FDA’s decision, CMS will cover this medication broadly while continuing to gather data that will help us understand how the drug works,” CMS Administrator Chiquita Brooks-LaSure said.  

Doctors must enroll patients in a registry that tracks their outcomes for two years, collect additional evidence about the drug’s risks and benefits, and submit data every six months. While an outside panel of experts recommended full approval of Leqembi in June, some worried about complications for select patients, including those taking anticoagulants.

Leqembi is not simple to use: It’s infused every two weeks by a medical provider. In addition to four MRI scans in the first year, patients need to get a separate test before treatment to confirm they have amyloid in the brain through PET scan or an invasive spinal tap. The drug has only been shown to help patients at the earliest stages of the disease.

Eisai has applied for approval of the drug in other markets including China, which has 10 million people 60 or older with dementia caused by Alzheimer’s disease. 

Read more: Lilly Gains as Therapy Slows Alzheimer’s Disease in Study

It could soon have competition. In May, Eli Lilly & Co. said its similar antibody drug, donanemab, slowed the disease in a final-stage trial. It has said it planned to complete a filing for full approval by the end of the second quarter. The drug is under review for approval in both Europe and Japan.

–With assistance from John Tozzi.

(Adds analyst comments in fifth paragraph.)

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