By Toni Clarke
Nov 15 An experimental drug to treat a rare
genetic disorder that causes skeletal malformation and a host of
related lung, eye, ear and heart problems confers "modest"
benefit, according to an initial review by the U.S. Food and
The drug, Vimizim, is being developed by BioMarin
Pharmaceutical Inc to treat Morquio A Syndrome, also
known as MPS IV-A. BioMarin shares rose as much as 8 percent.
The FDA review was posted on the regulator's website on
Thursday ahead of a meeting of outside advisers to the agency
scheduled for Nov. 19. The advisory panel will be asked to give
its own opinion on the drug. The FDA is not bound to follow the
advice of its advisory panels but typically does so.
The FDA review said the main safety concerns on Vimizim
relate to anaphylaxis and allergic reactions. It also said
further studies might be needed to better understand the role of
antibody development on long-term efficacy and safety.
Analysts, however, said they expected the advisory panel's
opinion to be favorable.
"Though the FDA may have expressed somewhat more caution
than some may have expected regarding Vimizim's efficacy ...
overall we did not see any major surprises given what is already
known about Vimizim's profile," Wells Fargo Securities analyst
Brian Abrahams wrote in a note.
Vimizim has been given "orphan drug" status by the FDA,
which means it will receive seven years of market exclusivity if
approved. An orphan drug treats diseases that affect fewer than
Vimizim, also known as elosulfase alfa, is expected to
generate sales of $532 million by 2018 if approved, according to
the average estimate of eight analysts polled by Thomson
Janney Capital Markets analyst Kimberly Lee said she
expected the drug to be approved by its Feb. 28 review date. Lee
has a "buy" rating on BioMarin's stock and a fair value estimate
Morquio A Syndrome is characterized by a deficiency of an
enzyme known as N-acetylgalactosamine-6-sulfatase (GALNS), which
causes excessive storage in the body of long chains of sugars
known as glycosaminoglycans.
This build-up can lead to short stature and joint
abnormalities that limit mobility and endurance. The disease can
also cause hearing loss, eye problems and heart disease.
Symptoms often appear before the age of five.
Morquio A Syndrome is one of a group of lysosomal storage
disorders known as mucopolysaccharidoses (MPS). Lysosomal
storage disorders are typically chronic and progressive, and
involve multiple organs of the body.
The FDA reviewed a BioMarin late-stage, or Phase III,
clinical trial of Vimizim. The main goal of the trial was to
improve symptoms as measured by a six-minute walk test. A
secondary goal was change measured by a three-minute stair climb
The company reported that after 24 weeks of treatment with
the drug, Vimizim increased patients' six-minute walk distance
by 22.5 meters compared with a placebo, a benefit the FDA
reviewers called "modest."
The advisory panel will be asked to give an opinion on
whether the 22.5 meter improvement is clinically meaningful.
There was no statistically significant change in the stair
test compared with placebo.
BioMarin shares were up 7 percent at $69.07 on the Nasdaq.
The stock touched a high of $69.59 earlier in the day.