Gene testing war looms for AstraZeneca heart drug

* Studies: AZ’s Brilinta, Lilly’s Effient don’t need tests

* Conflicting data on whether gene tests needed for Plavix

* Arrival of generic Plavix makes issue key to future sales

* Sanofi’s Plavix is world No. 2 drug with sales of $9.5 bln

By Ben Hirschler, European Pharmaceuticals Correspondent

STOCKHOLM, Aug 29 (BestGrowthStock) – Gene testing is shaping up to
be a marketing battleground for new blood thinners like
AstraZeneca’s (AZN.L: ) Brilinta, underscoring the power and
limitations of genetics as a tool to predict medical outcomes.

The arrival of generic copies of Sanofi-Aventis (SASY.PA: )
and Bristol-Myers Squibb’s (BMY.N: ) top-seller Plavix makes the
issue a hot topic scientifically and commercially, new studies
at the European Society of Cardiology congress on Sunday showed.

One study found AstraZeneca’s Brilinta, unlike Plavix,
requires no genetic testing to check if it will work, while
another showed Eli Lilly (LLY.N: ) and Daiichi Sankyo’s (4568.T: )
Effient also worked irrespective of gene variations.

On the face of it, the results of the two company-sponsored
trials give the firms valuable ammunition in a looming marketing
war with cheap copies of Plavix, or clopidogrel.

“Physicians don’t like complications, so if there was an
alternative to clopidogrel that worked the same way that did not
have these variations then most people would jump on it,” said
Alfred Bove of Philadelphia’s Temple University School of
Medicine.

But the evidence is far from clear-cut. A third study,
sponsored by Sanofi and Bristol, contradicted the idea that
people with a certain genetic make-up don’t benefit from Plavix.

The stakes are high because Plavix is the world’s second
biggest drug, with sales last year of more than $9.5 billion.
The drug is already off patent in parts of Europe and will lose
U.S. patent protection in 2012.

BRILINTA AWAITS APPROVAL

AstraZeneca believes Brilinta is better than either Plavix
or Effient, which has been linked to higher bleeding risk, and
is hoping the new gene data will add another string to its bow.

Brilinta is expected to win a green light to go on sale in
the United States as early as next month, after being endorsed
by a U.S. advisory panel last month. [ID:nN28178213]

An analysis of more than 10,000 patients in the PLATO study
found Brilinta cut the risk of heart attacks, strokes and
cardiovascular deaths more than Plavix, whether or not they had
a genetic variability that has been previously shown to affect a
patient’s response to clopidogrel.

The Effient study showed similar lack of impact from gene
variations, based on a smaller analysis of data from the TRITON
study. Both studies were published in The Lancet journal.

The link between Plavix response rates and genetics hit the
headlines in March, when the U.S. Food and Drug Administration
warned that some patients have a poor response to the drug
because they do not break it down well.

European regulators have not yet followed suit and Gilles
Montalescot of Hospital Pitie-Salpetriere in Paris said more
studies were needed before conclusions could be drawn about the
value of widespread genetic profiling.

That uncertainty was underlined by the third study, in the
New England Journal of Medicine, showing no difference between
poor metabolisers of Plavix and others among 6,000 participants
from two other trials, CURE and ACTIVE.

The lead researcher of that study, Guillaume Pare, said it
added “a further layer of complexity”, by showing that reported
genetic variants had no effect in certain patient populations.

“The whole field is in flux,” said David Holmes of the U.S.
Mayo Clinic in Rochester, commenting on the three studies.

“Everybody would like to think that personalised medicine is
going to be perfect. We just don’t have chapter and verse to
make sure that’s the case.”

Robert Califf of Duke University School of Medicine said it
appeared genetic variability was probably important for sicker
patients, including those having a stent to prop open clogged
arteries, but was less significant for lower-risk patients like
those in the CURE and ACTIVE studies.

For AstraZeneca, the dynamic situation means the company
will have to carefully balance superiority claims against the
price it plans to charge for Brilinta, medical experts said.

“It’s probably better to have more of your drug on the
market at half the price you thought it was going to be than
take 10 years to get it adopted,” said Bove.
(Editing by David Cowell)

($1=.7861 Euro)

Gene testing war looms for AstraZeneca heart drug