Key Information
Memantineexternal link, opens in a new tab, an oral medication that’s been used for decades to help treat Alzheimer’s disease, is generally tolerated well by people with sickle cell diseaseexternal link, opens in a new tab (SCD) and may help prevent painful disease crises, especially in children.
Those are the findings of a small, one-year study in Israel that tested the medication’s effects, particularly its safety, in adults and children with SCD.
Although more, larger-scale research needs to be done, the results imply that this Alzheimer’s treatment — which is no longer patent-protected and can therefore be produced relatively cheaply — might be able to be repurposed as a therapy for SCD patients, the scientists noted.
According to the researchers, “memantine has the potential to become a supportive and low-cost therapy in conjunction with [SCD prescription medication] hydroxycarbamide,” also known as hydroxyurea.
The study, “MeMAGEN: A Phase IIa/IIb open-label trial of memantine testing safety and tolerability in sickle cell patients,external link, opens in a new tab” was published in the journal HemaSphere. by a team from institutions in Israel and Switzerland.
An inherited disorder, SCD is causedexternal link, opens in a new tab by mutations in a gene needed to produce hemoglobin, the protein that red blood cells use to ferry oxygen in the bloodstream. The mutated hemoglobin tends to form clumps in red blood cells, deforming them into the sickle shape that gives the disease its name. Sickled blood cells are prone to getting stuck in blood vessels, which can block blood flow and lead to painful episodes known as vaso-occlusive crisesexternal link, opens in a new tab (VOCs).
Alzheimer’s drug memantine no longer patent-protected
Memantine is an oral therapy that’s been used since the early 2000s to help manage symptoms of Alzheimer’sexternal link, opens in a new tab, a progessive neurological disorder. It’s sold under the brand name Namendaexternal link, opens in a new tab, but the medication is no longer patent-protected and generic versions are available at a fairly low cost.
Previous studies have suggested that memantine can aid in stabilizing red blood cells, helping to prevent the clumping of mutated hemoglobin that causes disease complications in SCD. These findings have led some scientists to speculate that this cheaply available therapy might be able to be repurposed as an SCD treatment.
“In the best case, memantine would be available for the treatment of sickle cell anemia, as a well-tolerated, easy-to-store, and very cost-effective drug that is no longer patent-protected,” Max Gassmann, PhD, senior author of the study at the University of Zurich in Switzerland, said in a university news storyexternal link, opens in a new tab detailing the findings.
Having a cheap, easy-to-store option could be especially important in places such as Africa and India, where SCD is common and healthcare systems often lack resources.
An earlier pilot study (NCT02615847external link, opens in a new tab) tested memantine in four adults with SCD, with the results indicating that the therapy was generally tolerated wellexternal link, opens in a new tab. Now, researchers conducted a Phase 2 trial called MeMAGEN (NCT03247218)external link, opens in a new tab that tested memantine in 17 SCD patients who ranged in age from 10 to 40.
All of the patients were also taking hydroxyurea, an approved SCD treatment. Gassmann therefore noted that the study results “should … be interpreted as complementary to hydroxyurea.”