* Nine deaths in patients on top doses of Alzheimer's drug
* Testing of lower dose to continue in Phase II study
* Analysts say prospects for ELND005 now uncertain
* Elan shares down 2.3 percent
(Adds analyst comment, shares, background on bapineuzumab)
By Ben Hirschler
LONDON, Dec 15 Elan Corp ELN.I and Transition
Therapeutics Inc TTH.TO have dropped the two highest doses of
their experimental Alzheimer's drug from a mid-stage clinical
trial following nine deaths.
The news raised doubts as to whether the drug will now get
to market, industry analysts said, although the impact on
Irish-based Elan was limited as little value has so far been
attributed to the product.
Elan shares were off 2.3 percent in early trade on Tuesday.
Patients will be withdrawn immediately from the Phase II
study of ELND005 in the two higher dose groups, 1,000
and 2,000 mg dosed twice daily. The study will continue
unchanged for patients on 250 mg, the companies said.
The decision was agreed with the Independent Safety
Monitoring Committee for the 353-patient trial.
"Greater rates of serious adverse events, including nine
deaths, were observed among patients receiving the two highest
doses. A direct relationship between ELND005 and these deaths
has not been established," Elan and Transition said in a
Elan and Transition, a small Toronto-based drugmaker,
a worldwide development and commercialisation agreement in 2006
for the treatment.
An initial Phase I study for ELND005, an
drug, had produced encouraging results, showing that high
concentrations of the drug remained in brain tissue. The data
also found the treatment preserved choline acetyltransferase,
enzyme in neurons that helps protect nerve cells.
But Jack Gorman, an analyst at Davy Stockbrokers, said news
of the deaths in patients on high doses considerably increased
the perceived risk of the medicine reaching the market.
"At the very least efficacy at the lower dose will need to
be compelling to justify development and ultimate approval," he
said. "That said, we believe that little if anything is in
Elan's share price today for its Alzheimer's disease pipeline."
Elan is also developing another Alzheimer's drug called
bapineuzumab with Johnson & Johnson (JNJ.N), which has a
different mechanism of action and is in final-stage clinical
The highest dose of bapineuzumab was also dropped from
testing in April because of safety concerns.
Treating Alzheimer's disease is a "holy grail" of
but developing effective new therapies for the degenerative
brain disease has proved notoriously difficult.
(Editing by David Holmes; and Hans Peters)