By Donald Zuhn --
Today, in Tyco Healthcare Group LP v. Mutual Pharmaceutical Co., the Federal Circuit affirmed a decision on summary judgment by the District Court for the District of New Jersey that the claims of U.S. Patent No. 5,211,954 were invalid for obviousness. Tyco Healthcare Group LP and Mallinckrodt, Inc. ("Tyco") own the '954 patent, which has two independent claims directed to temazepan formulations. Claim 1 reads:
A hard gelatin capsule containing a temazepam formulation consisting essentially of 6 to 8 milligrams of crystalline temazepam having a surface area of from 0.65 to 1.1 m2/g and 95% of the temazepam having a particle size of less than 65 microns in admixture with a pharmaceutically acceptable carrier therefor.
Claim 2 differs from claim 1 only in that it recites a composition containing 7.5 mg of temazepam. Temazepam is a hypnotic (or sleep-inducing) drug that has been marketed internationally for the treatment of insomnia since the 1970's, and has been marketed in the U.S. since 1981 (under the name Restoril®). In 1991, Tyco's predecessor-in-interest began marketing Restoril® in 7.5 mg dosages.
Seeking approval to market a generic version of 7.5 mg temazepam, Mutual Pharmaceutical Co., Inc. filed an Abbreviated New Drug Application (ANDA) with the FDA. In response to Mutual's ANDA filing, Tyco brought suit against Mutual Pharmaceutical Co., Inc. and United Research Laboratories, Inc. ("Mutual") for infringement of claims 1 and 2 of the '954 patent. After Mutual received tentative approval for its ANDA, Tyco moved for a preliminary injunction. The District Court denied Tyco's motion on the basis that Mutual's ANDA disclosed a temazepam formulation in which the crystalline temazepam had a surface area of at least 2.2 m2/g, and therefore, the disclosed formulation could not literally infringe the '954 patent. Mutual then moved for summary judgment of noninfringement and invalidity, and the District Court granted Mutual's invalidity motion, determining that the '954 claims were obvious. In support of this determination, the District Court noted that Restoril® capsules had been sold in the U.S. in 15 mg and 30 mg dosages more than a year before the priority date of the '954 patent, the 1983 edition of the British National Formulary ("BNF reference") directed physicians to use temazepam at a dosage of between 5 and 15 mg for the treatment of insomnia in the elderly, and the parties agreed that physicians always seek to prescribe the lowest effective dose of any medication, particularly hypnotics such as temazepam.
In affirming the District Court's determination of obviousness, the Federal Circuit noted that "[t]he only physical feature distinguishing the ’954 claims from the Restoril® 15 mg capsules is the amount of temazepam contained in the capsule." The Court also noted that in a Supplemental New Drug Application filed for the 7.5 mg dosage, Tyco's predecessor-in-interest stated that for "[t]he formulation and manufacture of Restoril® Capsules, 7.5 mg are similar to that used for the 15 and 30 milligram capsules [and t]he formulation differs only in the reduction of the dose." "Given that uncontested description," the Court concluded that "the only limitation of the two '954 claims that was not fully disclosed by the prior art Restoril® capsules is the lower dosage of temazepam." As the Federal Circuit observed, that lower dosage can be found in the BNF reference, which discloses that temazepam can be used to treat insomnia and suggests the use of a dose of "10-30 mg (elderly patients 5-15 mg), increasing in severe insomnia to 60 mg." Citing Iron Grip Barbell Co. v. USA Sports, Inc., 392 F.3d 1317, 1322 (Fed. Cir. 2004), the Court noted that "[o]rdinarily, 'where there is a range disclosed in the prior art, and the claimed invention falls within that range, there is a presumption of obviousness.'"
On appeal, Tyco attempted to overcome this presumption of obviousness by showing unexpected results, that the 7.5 mg dosage enjoyed commercial success, and that the prior art teaches away from the claimed dosage range of 6 to 8 mg. Tyco also contested the District Court's interpretation of the BNF reference, relying on its expert's statement that the reference "nowhere states that a temazepam dose of 5 mg, 6 to 8 mg, or 7.5 mg, is effective in treating insomnia," nor "state[s] that 7.5 mg was effective" (emphasis added). Citing In re Spada, 911 F.2d 705, 708 (Fed. Cir. 1990), for the proposition that "[t]he discovery of a new property or use of a previously known composition, even when that property and use are unobvious from the prior art, can not impart patentability to the known composition," the Court countered that "[t]he recommendation in the BNF of a range of temazepam dosages that include the dosages claimed in the '954 patent renders obvious the claims to those dosages even in the absence of documentation in the BNF of the effectiveness of such dosages" (emphasis added).
In support of its teaching away argument, Tyco cited three references: (1) Nicholson 1976, which discloses that subjects given a 10 mg dose of temazepam produced a "marked reduction" in the time it took to fall asleep (i.e., sleep onset latency), but "little or no increase in total sleep time" (the '954 patent, in contrast, shows both reduced sleep onset latency and increased total sleep time); (2) Nicholson 1979, which discloses that subjects given 10, 20, or 30 mg doses of temazepam showed no statistically significant change in total sleep time or sleep onset latency; and (3) Matejcek, which states that "temazepam 5-mg values were excluded from the test procedure, since this dose is known to be of no clinical importance as a hypnotic." In response, the Federal Circuit observed that "none [of the references] states that a sleeping pill must achieve improvement on both parameters [i.e., total sleep time and sleep onset latency] in order to be considered effective." In addition, the Court noted that contrary to the cited statement in Matejcek, that reference "did include 5 mg temazepam capsules in its test procedure and displayed results for those capsules in two tables in the article."
With regard to Tyco's argument that secondary considerations support a finding of nonobviousness, the Federal Circuit discounted Tyco's citation of the '954 specification, which describes the experimental results as being "unexpected," stating that "[u]nsupported statements in the specification . . . cannot support a finding of unexpected results." As for Tyco's argument of commercial success (annual sales of the 7.5 mg capsules averaged more than $30 million over a decade), the Court stated that "[t]he district court acknowledged the product’s commercial success but properly found that the evidence as a whole did not overcome Mutual's strong prima facie case of obviousness." The Federal Circuit therefore upheld the District Court's determination on summary judgment that the two claims of the ’954 patent were invalid for obviousness.
Tyco Healthcare Group LP v. Mutual Pharmaceutical Co. (Fed. Cir. 2011)
Panel: Circuit Judges Newman, Bryson, and Gajarsa
Opinion by Circuit Judge Bryson
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