For the first time in 18 years, the Food and Drug Administration last week approved a new drug to treat Alzheimer’s disease, but for the more than 29,000 Hawaii residents suffering from the degenerative disease that destroys memory, questions remain about how to obtain the treatment and whether it will even work.

Up until now there were only five Alzheimer’s drugs on the market, all of which treat only symptoms. The drug aducanumab, which is being marketed by Biogen as Aduhelm, is intended to slow the progression of memory and thinking problems, though it can’t stop or cure the disease.

Patient advocacy groups pressured regulators to approve the drug, but top scientists, including a leading neurologist in Hawaii, have raised questions about the drug’s effectiveness. Kore Kai Liow, director and principal investigator at Hawaii Pacific Neuroscience, the only center in Hawaii to offer research treatments, said patients should be cautious in deciding whether to seek the treatment.

“I think it brings hope for the patient population currently that has no hope because this disease is without cure,” said Liow. “I’m happy for them that there is at least a disease-modifying drug. However, I’m skeptical, I’m cautious because most other drugs in this category have not been approved and have failed.”

The treatment, which involves a monthly intravenous infusion, is priced at $56,000 per year. It’s not yet clear how much of that cost may be picked up by health insurance, including Medicare.

Liow said patients might need to undergo a spinal tap to test for the disease in order for health insurance to cover the treatment because imaging scans aren’t available in Hawaii. He said a lot of the patients he treats tend to not opt for intravenous infusions because they are invasive and can be inconvenient.

The FDA’s approval of aducanumab has been plagued by controversy. An FDA advisory committee voted nearly unanimously against approving the drug. Three of the scientists on the 11 member committee resigned in protest of the FDA’s decision.

Aaron Kesselheim, a professor of medicine at Harvard Medical School and Brigham and Women’s Hospital, called the FDA’s approval of aducanumab “probably the worst drug approval decision in recent U.S. history,” in his resignation letter. He said the FDA’s approval of aducanumab, as well as another controversial drug, “would undermine the care of these patients, public trust in the FDA, the pursuit of useful therapeutic innovation, and the affordability of the health care system.”

Still, patient advocates applauded the FDA approval and coordinated a national media campaign around the announcement.

Maria Carrillo, chief science officer for the Alzheimer’s Association, said the FDA approval “ushers in a new era in Alzheimer’s treatment and research,” in a news release distributed locally. Joanne Pike, the association’s chief strategy officer, said eliminating barriers to accessing the drug was a top priority.

Liow, whose mother died of Alzheimer’s a dec­ade ago, said he understood where the patient advocacy groups were coming from.

“This is a very personal issue to me,” he said. “There was absolutely zero I could have done for my mother, so from a patient perspective I completely get it. The FDA is under tremendous pressure to approve something that gives them hope because there are so many drugs that fail. But to me, I think the evidence is weak at best.”