(Adds study data details)
By Bill Berkrot
March 28 Vertex Pharmaceuticals Inc
said on Tuesday its Kalydeco cystic fibrosis treatment given
with an experimental drug demonstrated significant improvements
in lung function in a pair of late-stage trials the company
plans to use to seek approval for the combination therapy.
Patient discontinuations of the Kalydeco/tezacaftor
combination due to adverse side effects, including
respiratory-related side effects, were low and similar to
placebo. That is important as bronchial constriction has led up
to 30 percent of those prescribed Vertex's Orkambi combination
treatment to stop taking it.
"If we could get the same efficacy but have a cleaner, safer
drug (than Orkambi) that would be a win and the results are
actually better than that," said Dr. Patrick Flume, an
investigator on both trials.
"I think they should be very excited about the news," added
Flume, professor of medicine and pediatrics at Medical
University of South Carolina, who said he expects the
combination to win approval.
Vertex plans to apply for U.S. and European approvals in the
third quarter. It also owns tezacaftor.
CF is a rare, life-shortening genetic disease affecting
about 75,000 people in North America, Europe and Australia that
causes progressive lung damage and loss of lung function. The
studies tested CF patients aged 12 and over.
In a study of more than 500 patients with two copies of the
F508del genetic mutation, which represents about 50 percent of
the CF population, the Kalydeco/tezacaftor combination led to an
improvement of 4 percentage points versus placebo in volume of
air exhaled in one second, a measure known as FEV1.
Analysts have said an improvement of 4 points or better with
few discontinuations would likely be viewed favorably by
In addition to the primary goal of the study, the oral drugs
showed significant improvements on secondary goals, including a
35 percent reduction in the annualized rate of lung infections
known as pulmonary exacerbations that cause hospitalization and
speed loss of lung function.
In the other study, the combination led to a mean absolute
FEV1 improvement of 6.8 percentage points compared to placebo in
patients with one copy of the F508del mutation and a second
genetic mutation, representing a small percentage of CF
patients. The improvement with Kalydeco alone was 4.7 percentage
points versus placebo in those patients.
Kalydeco, known chemically as ivacaftor, was given every 12
hours, while tezacaftor, previously known as VX-661, was taken
once a day. Kalydeco was the first approved drug that addressed
the underlying cause of CF rather than symptoms.
Vertex's approved medicines address about 29,000 CF
patients. It is testing drugs for a triple combination with
Kalydeco and tezacaftor that could eventually treat 80-90
percent of all CF patients, with data expected later this year.
(Reporting by Bill Berkrot in New York; Editing by Matthew
Lewis and Cynthia Osterman)