A federal judge upheld a U.S. patent for Pfizer Inc.'s (PFE)
blockbuster anti-impotence pill Viagra, preserving Pfizer's market
exclusivity on the drug into 2019.
U.S. Judge Rebecca Beach Smith in federal court in Norfolk, Va.,
ruled Friday that Teva Pharmaceutical Industries Ltd.'s (TEVA,
TEVA.TV) proposed generic version of Viagra would infringe a Pfizer
patent for the drug and that the patent is valid and
enforceable.
The 2019 patent covers the use of Viagra's active ingredient,
sildenafil, to treat erectile dysfunction. An earlier patent,
covering the basic compound, is due to expire next year; Teva
didn't challenge that patent.
At a trial that began in June, Teva argued that the 2019 patent
was invalid and unenforceable, while Pfizer defended it.
"We are pleased that the court recognized the validity and
enforceability of our Viagra patent for the treatment of erectile
dysfunction," Pfizer's general counsel, Amy Schulman, said in a
press release. "Protecting the intellectual property rights of our
innovative core is critical, and Friday's court decision
acknowledges Teva's clear violation of our patent rights."
A Teva spokeswoman couldn't immediately be reached.
Pfizer shares recently rose 2% to $18.22. Teva shares rose 1.1%
to $40.14.
Pfizer's victory, if it withstands any appeals--will give it a
much-needed financial boost during a tough stretch of years ahead.
The drug generates about $1 billion in U.S. sales. Leerink Swann
has estimated that continued market exclusivity could boost Pfizer
earnings by roughly 3% annually between 2013 and 2018, a period in
which profit otherwise would be under pressure due to the expected
loss of exclusivity later this year for Pfizer's top-selling
Lipitor cholesterol pill.
Yet Pfizer likely won't be able to retain all Viagra sales.
Viagra shares the same active ingredient as Pfizer's Revatio
treatment for pulmonary arterial hypertension, which is due to lose
patent protection next year. Some doctors are expected to prescribe
generic Revatio for erectile dysfunction, even though the doses are
slightly different than Viagra.
Viagra became one of the fastest-selling drugs in medical
history after its 1998 launch. Before then, men with erectile
dysfunction had few options. Viagra's success, helped by ubiquitous
television ads, spurred rivals to develop similar drugs, including
Eli Lilly & Co.'s (LLY) Cialis.
Viagra's discovery was serendipitous. Pfizer originally had
conceived sildenafil to treat heart-related conditions such as high
blood pressure. The drug's composition was covered by a patent
issued in the early 1990s and due to expire in March 2012.
During clinical testing, however, men taking sildenafil
experienced spontaneous erections. This led to Pfizer's decision to
develop the drug for ED.
Pfizer applied in the early '90s for a second patent covering
sildenafil's use to treat ED, which was eventually issued by the
U.S. Patent and Trademark Office in 2002. That patent is due to
expire in October 2019.
In court documents, Pfizer argued that it initially wasn't
obvious to people skilled in the art of drug research that an oral
formulation of sildenafil could be used to successfully treat ED.
Thus, Pfizer argued that its discovery was patent-worthy.
Teva argued that certain claims of the second patent are invalid
because prior research would have suggested to anyone skilled in
the art of drug development that drugs like sildenafil could be
used to treat ED. Teva also argued the second patent amounts to
"double-patenting" of Viagra.
In siding with Pfizer, Smith wrote that in the early to
mid-'90s, a person trained in the art of drug development "would
have no expectation that oral administration of such compounds
would be successful in treating ED, and thus such method was not
obvious to try."
Teva also claimed the second patent is unenforceable because
Pfizer engaged in "inequitable conduct" by withholding certain
information from the U.S. patent office. Teva alleged Pfizer failed
to inform the office in a timely manner of a dispute surrounding a
corresponding patent application in Canada. Pfizer said the
information was immaterial and was ultimately disclosed to the
patent office.
Teva's inequitable-conduct claim, however, stood on shakier
ground following a May 25 decision by the U.S. Court of Appeals for
the Federal Circuit in a patent dispute between Abbott Laboratories
(ABT) and Becton Dickinson & Co. (BDX), in a case dubbed
"TheraSense," a company purchased by Abbott.
The TheraSense ruling, which upheld an Abbott patent for
blood-glucose test strips that had been challenged by Becton
Dickinson, raised the standard for proving inequitable conduct. The
appellate judges said that a patent should only be rendered
unenforceable if the information withheld from, or misrepresented
to, the patent office was material to the agency's decision to
issue a patent.
Indeed, Smith cited the TheraSense ruling in her ruling on
Viagra. She wrote there was "utterly no evidence" behind Teva's
claims that the Canadian patent dispute was material to the U.S.
patent application or that Pfizer intended to deceive the U.S.
patent office.
"It is as if Teva hopes to conjure up the flame of inequitable
conduct from thin air," the judge wrote, likening Teva's
allegations to a "smokescreen."
Pfizer litigation on the 2019 patent for Viagra remains pending
against other generic companies, but no trials are scheduled in
those other cases.
-By Peter Loftus, Dow Jones Newswires; 215-982-5581;
peter.loftus@dowjones.com
--Jonathan D. Rockoff contributed to this article.