On Oct 26, 2018, Judge Kevin Mcnulty of District of New Jersey found method
of use patent of Zytiga® invalid under obviousness.
This is Hatch-Waxman actions for
infringement of US 8,822,438 brought by Janssen and BTG International
Ltd. The ‘438 patent contains twenty claims covering - methods for the treatment
of prostate cancer by administering various dosages of abiraterone acetate and
prednisone in combination. Plaintiffs alleged infringement of claims 4, 8,
11, 19 and 20, all of which dependent on claim 1 of the 438 patent, based on
the defendants’ filing of ANDAs. The Court conducted a bench trial beginning on
July 23, 2018 and concluding on August 2, 2018. As a defense to infringement,
defendants asserted that the ‘438 patent is invalid for lack of a written
description and for obviousness.
Written Description:
Defendants alleged that the
asserted claims in the ‘438 patent do not meet the written-description
requirement of 35 U.S.C. § 112. Specifically, defendants argued that the
specification is inadequate because it fails to disclose test results
showing that prednisone itself provides an anti-cancer benefit. Also, it
does not provide sufficient information to permit a POSA to understand that
both agents, abiraterone and prednisone, “treat” prostate cancer. Court
disagreed & said that the specification in the ‘438 patent sufficiently
identifies prednisone as an anti-cancer agent for purposes of
written-description requirement. The specification is directed to the
administration of abiraterone acetate with “at least one additional therapeutic
agent, such as an anti-cancer agent or a steroid.” Prednisone is explicitly
identified as an antibiotic agent under broad category of anti-cancer agent.
Second, the specification provides a list of steroids, including
hydrocortisone, prednisone, and dexamethasone. The specification also provides
the “amount of the steroid administered to a mammal having cancer is an amount
that is sufficient to treat the cancer whether administered alone or in
combination with a 170-hydroxylase/C17,2o-lyase inhibitor.” Thus, whether
identified as either an “anti-cancer agent” or a “steroid,” prednisone is
sufficiently identified in the specification as an agent that “treats” cancer.
Therefore, claims have written description support.
Obviousness:
Defendants alleged that the
combination therapy claimed in the ‘438 patent would already have been obvious
to a person of ordinary skill in the art (“POSA”) under 35 U.S.C. § 103.
Defendants asserted that, as of that date, a POSA familiar with the prior art
would have been motivated to combine abiraterone acetate with prednisone for
three reasons: (1) for its anti-cancer effects; (2) to mitigate abiraterone’s
side effects; or (3) for prednisone’s palliative properties. The crux of
defendants’ argument is that the prior art would have motivated a POSA to
combine abiraterone with prednisone with a reasonable expectation of success.
Court in its analysis said that by
the priority date of Aug. 25, 2006, it was understood that both ketoconazole
and abiraterone were steroid inhibitors, and both inhibited the CYP17 enzyme. Barrie
1994 and O’Donnell 2004 both used ketoconazole as a
starting point for their discussions regarding abiraterone and its potential to
be a more selective inhibitor. Barrie 1994, comparing the inhibition levels of
hormone production by abiraterone with ketoconazole, concludes that abiraterone
was more effective than ketoconazole in decreasing testosterone levels.
O’Donnell 2004 specifically notes that abiraterone’s ability to sustain
testosterone suppression in castrate males, when given in 500 to 800 milligram
doses, suggested that it could be used as a second-line treatment. From all of
this, it can be concluded that abiraterone had been identified in the prior art
as a second-line prostate cancer treatment. It can also be concluded that it
was regarded as a superior swap for ketoconazole, in that it performed a
parallel function in a more targeted manner. As for prednisone itself, Tannock
1996 suggested that corticosteroids provide some level of palliation to
cancer patients. Sartor 1998 goes farther, and suggests that
prednisone can cause reduced PSA levels, a marker of anticancer effect. That
conclusion is supported by three other prior art references: Fossa 2001,
Fakih 2002, and Harris 2002. Thus, there was more than sufficient
motivation for a POSA to combine abiraterone with prednisone.
Moreover, Gerber 1990
suggests that a patient whose PSA levels are increasing can be treated with a
combination of ketoconazole and a glucocorticoid, which can result in a
decrease in PSA levels. Gerber 1990 also teaches that the combination of
ketoconazole and 5mg a day of prednisone, twice daily, is safe and effective
for treating hormone-refractory advance prostate cancer. O’Donnell 2004
corroborates that in the clinical use of ketoconazole, it was “common practice”
to administer supplementary hvdrocortisone. It states cautiously that “further
studies with abiraterone acetate will be required to ascertain if concomitant
therapy with glucocorticoid is required on a continuous basis, at times of
physiological stress, if patients become symptomatic or indeed at all.” Thus, A POSA would have
interpreted ketoconazole’s clinical use as a basis to take the next
investigative steps with abiraterone. It made sense to replace ketoconazole
with abiraterone, as it became clear that abiraterone was a superior, more
selective inhibitor. Co-administration of 10mg per day of prednisone would
naturally carry over from the ketoconazole combination therapy to the
abiraterone combination therapy. There would have been concerned about the
potential reduction in cortisol as a side effect of abiraterone’s inhibition of
CYP17. Specifically, a POSA would have seen the potential for resulting excess
mineralocorticoid (aldosterone) and adrenal insufficiency. They do not,
however, outweigh the clear teaching in prior arts & court did not agree,
as plaintiffs suggest, that prior art “taught away” from the combination
therapy. In short, to the POSA, the prior art would have suggested that
abiraterone could be combined with prednisone with a reasonable probability of
success.
With respect to secondary
considerations court held that these factors do not overcome convincing
evidence of obviousness. As to the commercial success factor,
there can be no dispute that ZYTIGA® has yielded billions of dollars in sales.
“Evidence of commercial success . . . is only significant if there is a nexus
between the claimed invention and the commercial success.” Moreover, “if the
feature that creates the commercial success was known in the prior art, the
success is not pertinent.” Onnco, 463
F.3d at 1311-12; see also fT. Eaton, 106 F.3d at 1571. Also, “where ‘market
entry by others was precluded [due to blocking patents], the inference of
non-obviousness of [the asserted claims, from evidence of commercial success,
is weak.’” Galdenna Labs., L.P. v.
Tolmar, Mc, 737 F.3d 731, 740 (Fed. Cir. 2013) (quoting Merck, 395 F.3d at
1377). Defendants argued that Abiraterone was previously known in the art
& there is earlier blocking patent, US
5,604,213. From 1997 through 2016, that patent granted its holder the
exclusive right to market abiraterone. Also the sales of ZYTIGA may not be
wholly attributable to the patented combination therapy. These are powerful
offsetting factors. With respect to long-felt need and unexpected
results, Plaintiffs stated that the claimed invention was an advance on the
prior art in that it had less toxicity, was better tolerated, and improved
overall survival. Defendants pointed to existing contemporaneous alternatives: Jevtana was approved by the FDA in
2010, a year before ZYTIGA® was approved; Xtandi
was approved in 2012. Therefore, court held that it does not suggest that all
other efforts had failed, or that the abiraterone/prednisone combination
therapy was unexpected “ in kind and not merely in degree.” Thus, balancing the
entire prior art and the other indicia, court found that the evidence favors a
conclusion of obviousness.
Judge also ruled on infringement issue & found patent infringed by Defendants if it would have been held valid.