When the F.D.A. mandates randomized double-blind clinical trials (RCTs) be successfully performed before allowing the use of a new drug, it also mandates that diverse promising drugs will never be tested. Some of those drugs might help or even cure Alzheimer’s. The reason that some diverse promising drugs will never be tested, as explained by Gina Kolata in the passage quoted below, is that there are too few diagnosed and willing Alzheimer’s patients to conduct the number and kind of RCTs that the government mandates, for all the promising drugs under development. What is the alternative to mandated RCTs? Allow physicians to prescribe drugs that have a promising rationale. If their patients benefit the physicians will continue to prescribe the drug and they will tell their colleagues.
(p. D1) The task facing Eli Lilly, the giant pharmaceutical company, sounds simple enough: Find 375 people with early Alzheimer’s disease for a bold new clinical trial aiming to slow or stop memory loss.
There are 5.4 million Alzheimer’s patients in the United States. You’d think it would be easy to find that many participants for a trial like this one.
But it’s not. And the problem has enormous implications for treatment of a disease that terrifies older Americans and has strained families in numbers too great to count.
The Global Alzheimer’s Platform Foundation, which is helping recruit participants for the Lilly trial, estimates that to begin finding participants, it will have to inform 15,000 to 18,000 people in the right age groups about the effort.
Of these, nearly 2,000 must pass the initial screening to be selected for further tests to see if they qualify.
Just 20 percent will meet the criteria to enroll in Lilly’s trial: They must be aged 60 to 89, have mild but progressive memory loss for at least six months, and have two types of brain scans showing Alzheimer’s is underway.
Yet an 80 percent screening failure rate is typical for Alzheimer’s trials, said John Dwyer, president of the foundation. There is just no good way to quickly diagnose the disease.
The onerous process of locating just 375 patients illustrates a grim truth: finding patients on whom to test new Alzheimer’s treatments is becoming an insurmountable obstacle — no matter how promising the trial.
With brain scans, lab tests and memory tests, the cost per diagnosis alone is daunting — as much as $100,000 for each person who ends up enrolled in a trial, Mr. Dwyer said — even before they begin the experimental treatment.
Complicating the problem, the number of trials has exploded in recent years. There (p. D4) are more than 100 Alzheimer’s studies looking for a whopping 25,000 participants, Mr. Dwyer said.
To begin filling them all, 37.5 million patients in the right age group would first have to be informed. Ten percent would be referred to a trial site for screening.
Just 4 percent will move forward with an evaluation, and of these, just over 17 percent will drop out, given the current rate, leaving roughly 125,000 to be screened. And with an 80 percent screening failure rate, that leaves 25,000 participants of the 37.5 million who were first informed.
The numbers make it clear: There’s no way scientists are going to find 25,000 participants for all of the Alzheimer’s trials that have been approved.
“The irony is that the science has never been more promising,” Mr. Dwyer said. “How many promising drugs will be abandoned or their evaluation seriously delayed? Some good science is going to be left on cutting-room floor.”
For the full story see:
(Note: the online version of the story has the date July 23, 2018 [sic], and has the title “For Scientists Racing to Cure Alzheimer’s, the Math Is Getting Ugly.”)