By Toni Clarke
WASHINGTON May 22 Merck & Co's
experimental insomnia drug was safe and effective at the lower
of two doses studied, a panel of medical experts said on
Wednesday, increasing the chance it will be approved by the U.S.
Food and Drug Administration.
The advisory panel was convened to help the FDA decide
whether to approve the drug, suvorexant, which would be the
first in a new class of sedatives designed to help people fall
asleep and stay asleep.
On Monday, the FDA's internal reviewers published a report
expressing concern about the drug's potential to cause next-day
sleepiness and impaired driving. They asked the committee to
consider whether patients should be started at a lower dose than
that recommended by Merck.
Merck proposed that elderly patients start by taking 15
milligrams of the drug and increase that to 30 if necessary. The
company recommended non-elderly adults start on 20 milligrams
and increase it to 40 milligrams if needed.
On Wednesday, the FDA reiterated its opinion that there was
little evidence in Merck's data to show that the higher dose was
more effective than the lower dose, and considerable evidence to
show it was less safe.
The FDA's reviewers pointed to an increase in the risk of
suicidal thoughts and behaviors, an increased risk of impaired
driving, and an increased risk of severe sleep disturbances.
Speaking for the FDA, Dr. Ronald Farkas noted cases in which
patients had reported sleep paralysis and terrifying
hallucinations. He also expressed the agency's concern about the
drug's impact on driving.
"What we are trying to prevent is criminal prosecution of
patients taking their drug as prescribed," he said.
Merck celebrated the panel's recommendation, saying in a
statement that it was "excited about the potential of suvorexant
as a new and different approach to treating insomnia."
The FDA is not bound to follow the advice of its advisory
panels but typically does so.
The FDA had asked the panel to consider whether patients
should start with a 10 milligram dose, saying data from a
smaller trial showed that amount might work for some people.
Merck disputed that, saying 10 milligrams would not be
The FDA asked the panel if Merck should conduct an
additional trial to further evaluate a 10 milligram dose. The
panel voted against that. Some panelists agreed with Merck that
10 milligrams would not be effective. Others agreed in principal
with a lower starting dose, but said a new trial would not add
meaningfully to the information already in hand.
The panel voted 13-3, with one abstention, that the drug is
safe for elderly patients at 15 milligrams a day and for
non-elderly adults at 20 milligrams. It voted 8-7, with two
abstentions, that the drug is not safe at 30 and 40 milligrams.