Questions over the efficacy of Vytorin and Zetia could
prompt a sharp pullback on first- and second-line use of the drug, according to
a survey of physicians by GfK Market Measures, but docs are taking a
wait-and-see approach with the drugs and remain open to new data.
The study found general and family practitioners to be most
wary of the drugs, with those respondents reporting they will switch upwards of
40% of their patients on Vytorin and Zetia to other therapies over the next few
months. Cardiologists and internists, by contrast, anticipate switching 25%-30%
of their patients off the drugs.
Switches will be most precipitous in first-line use (general
and family practitioners would switch 20% of patients receiving the drug as a
first-line therapy), followed by second-line use (with an anticipated 8%-14% of
patients affected across all specialties). Use of Vytorin as a third-line
therapy is likely to increase—by as much as 30% of patients.
“There is obviously an opportunity over the next several
months for Lipitor and Crestor to capture additional market share,” said GfK's
Anna Marie Napolitano. “On the other hand, for Vytorin and Zetia, our research
shows a window of opportunity to mitigate the impact of the trial results.” The
survey found that physicians are counseling patients to wait until their next
visit to talk about alternatives, and Napolitano notes that they will be
watching closely for the results of the FDA's review and report on the trial,
which is not due until later this year.
The January Internet survey of 150 physicians, including
general/family practitioners, internists and cardiologists, was intended to
gauge doctor reaction to the ENHANCE trial, an imaging study which found
Vytorin was no more effective than simvastatin alone for reducing arterial wall
thickness in a small group of patients with a genetic predisposition to
Merck/Schering-Plough says the findings, which are expected
to be presented in full at the American College of Cardiology's annual
conference at the end of March, have been widely misrepresented in the press
and that the trial, involving a small number of patients with a particular
condition, should not be extrapolated to the broader population.
“We set a high hurdle for ourselves,” said Lee Davies,
global director of product communications for Schering-Plough, noting that 80%
of the trial patients had already been on a statin prior to the study. “The walls
were thin to begin with, so we were looking for even further reductions.”
The ACC and the American Heart Association have both urged
against reading too much into the results of the trial until more is known. The
results generated intensive coverage in the news media and attracted
congressional attention due to delays in their release and an attempt by the
companies—ultimately scuttled—to change the primary endpoint. Critics charge
the joint venture with trying to fudge embarrassing numbers. The companies say
the novelty of the imaging techniques used in the study presented difficulties
which prompted the delay.
Merck/Schering-Plough has three trials underway measuring
clinical outcomes, Davies said. The first, the SEAS trial of 3,500 patients
with aortic stenosis, could be available in time for the American Heart
Association convention in November. Two more trials are slated to wrap up in
2011—the SHARP trial involves 5,000 patients with chronic kidney disease and
the IMPROVE-IT trial involves 12,500 patients.