Alzheimer's disease isn't something you must either passively accept or dread, a panel of doctors and scientific experts told an audience of more than 500.
There are new reasons to think Alzheimer's can eventually be cured or prevented, perhaps with drugs already on the market, according to the panel.
People can also strengthen their cognitive muscles in advance so their brains can better resist decline, panelists said at the annual Date With A Cure, held by Alzheimer's San Diego at Qualcomm Hall in Sorrento Valley, Calif. And they can help research by volunteering for clinical trials. Hispanics, who are underrepresented in studies, are especially needed.
Gloom descended on the field in March, when clinical testing of a much anticipated drug called aducanumab was halted for lack of efficacy. The drug clears a toxic brain protein called beta amyloid believed to trigger the disease. But the treatment apparently was given too late. So researchers have increased efforts to find drugs to prevent the disease.
Certain HIV drugs may prevent Alzheimer's, said panelist Dr. Jerold Chun of Sanford Burnham Prebys. These drugs inhibit an enzyme called reverse transcriptase that copies HIV into the genome of host cells. HIV patients, who get these drugs, have an extremely low rate of Alzheimer's compared to the general population Chun said.
The drugs might work by preventing genetic changes from taking place in the brain of Alzheimer's patients, caused by units of DNA that jump around the molecule, changing its sequence.
These changes during the patient's lifetime may help explain why anti-amyloid drugs haven't worked, Chun said. They target a single form of amyloid, while genetic recombination might generate thousands of varieties of amyloid that current drugs can't touch.
Doctors can prescribe reverse transcriptase inhibitors now to individual patients who in their judgment are at risk for Alzheimer's as an "off-label" use, Chun said. Risk factors include genetic variants, age and symptoms of early cognitive decline. But to move from these one-off uses to large-scale adoption, controlled clinical trials are necessary.
To give Alzheimer's drugs their best chance of success, those at elevated risk should be treated before damage begins. Major progress toward this goal has been made, said panelist Dr. Paul Aisen. He heads the University of Southern California's Alzheimer's Therapeutic Research Institute, based in San Diego.
Currently, amyloid deposits are detected in expensive PET imaging tests, Aisen said. These are useful to find appropriate subjects for clinical trials. But they're too costly for general use. So subjects are selected by pre-screening for early symptoms of potential decline.