* Good news for new PCSK9 drug class but needs confirmation
* Sanofi, Regeneron vying with drugs from Amgen and Pfizer
* Data from four alirocumab studies unveiled at ESC congress
By Ben Hirschler
BARCELONA, Aug 31 An experimental
cholesterol-lowering drug from Sanofi and Regeneron
Pharmaceuticals roughly halved the number of heart
attacks and strokes in a clinical trial, researchers reported on
The result is not conclusive, because the analysis was done
retrospectively, but it provides the first evidence that
targeting a protein known as PCSK9 could slash cardiovascular
risks for millions of patients.
The injectable drug, alirocumab, is from a new class of
medicines, which are also being developed by Amgen and
Pfizer. They lower "bad" LDL cholesterol in a new way
and are widely expected to reap multibillion-dollar sales.
The finding is likely to spur enthusiasm about the drugs,
which could reach the market next year, although experts said it
still needed to be confirmed in a much larger trial.
Sanofi and Regeneron said in July that nine big studies
showed consistent LDL reductions with alirocumab, but details
from four of these trials have only now been unveiled at the
European Society of Cardiology annual meeting in Barcelona.
The encouraging cardiovascular data come from an interim
safety analysis of one of these studies showing patients on
alirocumab were less prone to a combination of cardiovascular
events, including cardiac death, heart attack, stroke and chest
pain requiring hospitalisation.
Both groups of patients got traditional anti-cholesterol
statin pills in addition to alirocumab or a placebo. Among the
alirocumab group, 1.4 percent of patients suffered a major
cardiovascular event against 3.0 percent of those on placebo.
The ongoing 2,341-patient study, called Odyssey Long Term,
is expected to conclude early next year but researchers said the
early sign of efficacy was clearly positive.
"To have this result emerge so quickly in this study is very
encouraging," said Jennifer Robinson, a cardiologist at the
University of Iowa, who led the study.
No other drugmaker has previously released data suggesting
reduced cardiovascular risk from PCSK9 inhibitors.
Patrick O'Gara of the Brigham and Women's Hospital in Boston
and president of the American College of Cardiology said the
finding was "biologically plausible" but the post-hoc or
retrospective nature of the analysis necessitated caution.
"It's so much wished-for that we must be careful," he said.
WATCHING SIDE EFFECTS
Sanofi and Regeneron are in a fierce race with Amgen, which
last week became the first company to file with regulators to
sell its product evolocumab.
The French and U.S. partners hope to close the gap after
paying $67.5 million last month for a voucher from BioMarin
Pharmaceutical designed to assure alirocumab an
expedited U.S. regulatory review.
It is unclear if the rival PCSK9 drugs will prove to be very
different from each other but Sanofi's research head Elias
Zerhouni thinks alirocumab should enjoy an early advantage from
the preliminary indication of improved cardiovascular results.
That may help convince cost-conscious healthcare providers
to pay up for an expensive new medicine before results from the
large 18,000-patient trial are available in 2017 or 2018.
"It has to be confirmed by the big outcomes study but it is
the first scientific indication that there is something other
than a statin that potentially shows you can get a reduction in
risk," Zerhouni told Reuters.
All four trials presented in Barcelona showed alirocumab cut
LDL by around 50-60 percent after 24 weeks. Side effects
included stuffy nose and upper respiratory tract infections.
Doctors and regulatory authorities are watching closely to
see if cutting LDL so sharply may have an adverse effect on
other parts of the body, notably the brain.
So far, there is no sign of this. There was a small
non-statistically significant trend towards more neurocognitive
problems in Odyssey Long Term but the other three studies showed
alirocumab patients had fewer such issues.
PCSK9 drugs will be targeted first at people with a rare
familial condition that raises their cholesterol dangerously, as
well as statin-intolerant patients and those at high-risk of a
heart attack who struggle to control LDL on current medicines.
Sanofi and Regeneron estimate this high-risk group totals
around 21 million patients in the United States and Europe.
Whether the drugs, which will be offered in pre-filled
syringes and auto-injector pens, will be used more generally
depends on how their cost-effective they are deemed to be.
The companies say it is premature to talk about price but it
is clear the antibody-based therapies will not be cheap, with
Barclays analysts suggesting $6,000 a year as a possible price
in the United States, with a lower price likely in Europe.
(Reporting by Ben Hirschler. Editing by Jane Merriman)