* EnVivo drug acts on nicotine receptors
* Drug showed a benefit on top of current treatments
By Julie Steenhuysen
VANCOUVER, British Columbia, July 18 An
experimental Alzheimer's drug that activates a specific nicotine
receptor in the brain improved measures of thinking and memory
over a six-month period in patients with mild to moderate
disease, U.S. researchers said on Wednesday.
Most drugs being studied for Alzheimer's aim to keep the
disease from progressing. But the experimental drug made by
privately held EnVivo Pharmaceuticals Inc of Watertown,
Massachusetts, is intended to improve Alzheimer's symptoms.
In the phase 2 study, EnVivo's drug called EVP-6124 was
tested in 409 patients with mild to moderate Alzheimer's, many
of whom were already taking Pfizer Inc's Aricept, known
generically as donepezil, or Novartis AG's Exelon,
known generically as rivastigmine.
Even so, patients who took the 2 milligram dose of EVP-6124
showed a statistically significant increase in measures of
cognitive function after 23 weeks.
"These are very encouraging data," said Dr. Dana Hilt, chief
medical officer of EnVivo, who is presenting the study's
findings at the Alzheimer's Association International Conference
in Vancouver, British Columbia.
He said that even though the drug was used in a mixed group
of patients, some of whom were taking additional medications and
others who were not, it improved both their thinking skills and
their ability to function in daily life.
"It is statistically and clinically significant," Hilt said.
Most current drugs under study to treat Alzheimer's,
including Pfizer and Johnson & Johnson's bapineuzumab
and Eli Lilly and Co's <LLY.N > solanezumab, are being tested in
the hopes of stopping progression of the brain-wasting disease,
but they will not necessarily improve existing symptoms.
Researchers say there is still a need for effective drugs to
treat the symptoms of Alzheimer's, which affects some 5 million
Americans and as many as 35 million people worldwide.
"The idea of developing a drug that improves symptoms that
we could use with a disease-modifying agent is very important to
me," said Dr. Jeffrey Cummings, who directs Alzheimer's programs
at the Cleveland Clinic in Las Vegas and Cleveland and is a paid
consultant for EnVivo.
"My patients want to get better. They don't just want to get
worse more slowly," Cummings said.
Aricept and several drugs like it work by keeping an enzyme
called cholinesterase from breaking down acetylcholine, an
important neurotransmitter for memory and thinking that declines
as Alzheimer's progresses.
EnVivo's drug works differently, targeting a nicotine
receptor in the brain called alpha 7 that is related to
cognition and memory.
Cummings said the drug selectively targets just that part of
the nicotine receptor that benefits cognition without
stimulating the effect that causes dependency.
"It was a relatively small, phase 2 study, but they did see
a cognitive benefit that suggests we would want to look
further," said Dr. Laurie Ryan, who heads up Alzheimer's
clinical trials at the National Institute on Aging, a part of
the National Institutes of Health.
The company plans to test the drug in large, phase 3
clinical trials starting next year.
"Every little bit of functionality we return moves patients
closer to normal and gives them a higher quality of life," said
William Thies, chief medical and scientific officer at the