It is the first drug proven to slow the progression of Alzheimer's disease. Why is it a slow start?

The first drug proven to slow the progression of Alzheimer's disease hit the U.S. market more than a year ago, but sales have been slow, major hospital systems are taking months to begin using it, and some insurance companies are slowing it down. Denied insurance coverage.

Doctors also expect some patients will be hesitant to take Rekenbi because of its limited efficacy and possible side effects. They say it will take years to learn how best to deploy the drug and work needs to be done to improve diagnosis.

“This is the beginning of a very exciting journey,” said Dr. Amber Krushleshta, a family physician in suburban Atlanta who specializes in dementia patients.

More than 6 million Americans and millions more around the world have Alzheimer's disease, the most common cause of dementia. Although there is no cure, Requembi removes a sticky brain protein called amyloid, which is a key indicator of Alzheimer's disease.

Studies have shown that when given to people with mild symptoms, it can slow the progression of the disease by several months. Some experts say this delay may be so subtle that patients don't notice it.

This drug can also cause swelling and bleeding in the brain. Patients need regular brain scans to monitor it.

The Food and Drug Administration last summer granted full approval to Requembi for patients in the early stages of the disease. The federal Medicare program for people age 65 and older covers the cost of the recembi and the scans needed to diagnose the patient.

The drug's maker, Japan's Eisai, initially expected 10,000 patients to take the infusion by the end of March. Company executives later retracted that forecast, although they said sales were growing.

Eisai Vice President Alexander Scott said it is taking longer than expected for hospitals and health systems to set up systems to administer Rekenbi.

“We're not adding drugs to an existing system,” he says. “They're building a drug system.”

Cedars-Sinai Health System in Los Angeles began administering the drug in early March. Getting there required months of meetings to develop a plan to coordinate diagnosis, treatment, and monitoring of the problem.

“We were very cautious about this,” said behavioral neurologist Dr. Sarah Klemen.

Banner Health in Arizona also recently began using Requembi at some specialty clinics in Phoenix, a spokesperson said.

“This is a very gradual and step-by-step approach,” said Dr. Alireza Atli, a neurologist who worked as a paid consultant for Eisai. “As we learn more, we will continue to expand and extend it.”

The Mayo Clinic in Rochester, Minn., began using Rekenbi in October, but limited it to patients living within a 100-mile radius so that it could be delivered quickly if side effects appeared. Dr. Ron Petersen, an Alzheimer's disease expert, said doctors evaluate three to five patients each week for possible treatment.

Health systems are still trying to figure out how coverage for the drug, its infusions, and the necessary tests will work so patients don't have to worry about the bills. This is an important variable for a drug that can cost more than $26,000 per year.

An Eisai spokeswoman said nearly three-quarters of U.S. commercial plans cover the drug outside of Medicare.

But doctors worry that coverage may still be difficult for some patients, especially those who are too young to qualify for Medicare.

Insurance denials delayed Scott Berkheiser's first IV infusion for several months until December of last year. The 57-year-old Venice, Florida, resident said the drug company ultimately agreed to give him the doses for free while he paid his co-pay for the IV.

“It was kind of crazy,” he said. “It seemed like a game that made sense for financial reasons.”

Starting treatment on time remains another challenge.

Texas Neurology had 60 patients tested and on a waiting list as candidates for Requemby when the drug was launched last year. Only eight people ultimately started treatment. The remaining patients either refused to be tested or had progressed beyond the mild stage when retested, CEO David Evans said.

“That period quickly becomes very short,” he said.

Doctors say more needs to be done to quickly identify patients and start treatment before the disease progresses. But it's a vague process.

When people mention memory problems, doctors need to rule out reversible causes such as thyroid problems, vitamin deficiencies, medication issues and depression, Kulshreshta said. That way, memory testing for dementia will require several visits.

Some patients may not be able to receive Rekenbi because it conflicts with medications they are already taking to prevent stroke.

And it can sometimes take months to see a neurologist and get a prescription for medication.

Those who successfully received their first infusion say that the treatment process is manageable. Berkheiser said the IV has been going “like clockwork” since the late start.

He fits them in between his job as an engineer and training six days a week to compete in an Ironman triathlon.

Charles “Bam” Clegg recently completed his 13th Rekenbi IV infusion. The Salem, Alabama resident visits his treatment center just 15 minutes from his home.

Mr Clegg and his wife Carol said there were no side effects and his short-term memory improved.

“This medicine gives you hope,” Carol said.

Access to treatment may improve over time. The FDA is considering another potential treatment that targets amyloid proteins, Eli Lilly's donamab. Eisai plans to seek approval for an injectable version of Rekenbi that is easier to use. Blood tests may eventually speed up the detection of amyloid.

But researchers say there's still a long way to go. The cause of Alzheimer's disease is not clear, and many believe that a combination of treatments is needed to stop Alzheimer's disease.

“We still have a lot to learn about Alzheimer's disease,” says Dr. Eric Widera, a geriatrics expert at the University of California, San Francisco. “It's complex and goes way beyond amyloid.”

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