Alzheimer’s trials offer little certainty for investors, patients

Data from two of the leading companies developing Alzheimer’s drugs left patients, researchers and investors with a frustrating message: keep waiting.

Trial results released Wednesday on two experimental drugs didn’t deliver a definitive answer as to whether the medications will work. Eli Lilly and Co.’s trial showed that patients who had been taking its drug longer did better on a cognitive test than those who hadn’t. Biogen Inc. reported data that further muddied the question of what dose of its drug is most effective.

That offered investors little clarity as to whether either company might be the first with an effective treatment to slow or stop the memory-destroying disease.

Lilly shares were essentially unchanged in late-morning trading, listed for $85.46, after an intial dip earlier in the day. Biogen shares slipped 3 percent to $397.76. Both stocks had climbed more than 34 percent over the past year as optimism spread about the potential of their drugs to impact the ailment.

Alzheimer’s has been a graveyard of drug development, leaving millions of Americans who have the disease waiting for a treatment. Companies have wagered that it’s worth the risk, since the first to get a successful therapy to market will probably reap billions of dollars in sales.

Data from the trials was released at the Alzheimer’s Association International Conference in Washington.

Biogen’s 166-patient, early-stage trial was an attempt to find which dose of the drug did the best at helping patients on cognitive tests.

Earlier data had already demonstrated that the drug showed a better response at higher doses, though it also showed harsher side effects. The new results didn’t provide clear direction on whether a dose somewhere in the middle would be the answer.

Lilly’s trial was a 1,322-patient extension of two previous experiments. The trial showed that patients who had gotten the Lilly drug solanezumab at the start of treatment instead of a placebo would maintain their better scores on cognitive tests. It was a positive result, though not the the definitive answer Lilly is seeking from another trial that would be used for regulatory approval.

A former Food and Drug Administration official questioned the usefulness of Lilly’s study, since the phase 3 trials it was built from weren’t successful.

“The primary analyses of both these trials were negative,” said Rusty Katz, former director of the FDA’s Division of Neurology Products.

“We sort of live and die by the primary analyses, and when the primary analyses are negative all other analyses are suspect,” he said at the AAIC meeting in Washington.

Both companies are pushing ahead with late-stage studies of their drugs, betting that patients will embrace a treatment that could slow their cognitive decline — even if it can’t stop it.

“Slowing the rate of progression of disease by one third is an important change on the long-term trajectory, on the long- term impact of the disease,” Paul Aisen, a neuroscientist at the University of California at San Diego who worked as a consultant for Lilly on its drug, said at the AAIC meeting.