Wyeth v. Abbott Labs. – Picking Plaintiff’s Poison

In July of 2011, I wrote a post for this blog on BSC v. J&J, a Fed. Cir. decision in which four J&J patents claiming stents eluting rapamycin, a drug that inhibits restenosis after balloon angioplasty, were held invalid for failure to meet the requirements of the written description requirement of s. 112 (1) [now s. 112(a)]. While the specification only disclosed stents releasing rapamycin, the claims used broader language, such as “rapamycin or a macrocyclic triene analog of rapamycin.” While such analogs were known, none were named in the specification. Still, J&J must have felt that they had a fighting chance, since a specification need not describe that which is known to the art.

A three-judge panel of Moore, Bryson and Gajarsa found that the claims failed to meet the WDR. However, instead of explaining why the specification read in combination with the knowledge available to the art about rapamycin analogs fails the UC v. Lilly WDR standards, Moore and Bryson relied on the deficiencies they found in the specification:

“Given the absence of information regarding structural characteristics of [rapamycin analogs] in the specification, the unpredictability of the art and the nascent state of using drug eluting stents…we affirm the [grant of SJ]. The patent laws do not reward an inventor’s invitation to other researchers to discover which of the thousands of macrocyclic lactone analogs of rapamycin could conceivably work in a drug-eluting stent.”

Judge Gajarsa concurred in the result, but noted that this rationale sounds a lot like it is based on a failure to meet the enablement requirement of s.112(a):

“The majority’s opinion further extends the [WDR] into the realm of enablement. Much of the confusion in this case is due to the difficulty of determining how the [WDR] applies to novel compounds as opposed to novel combinations of known elements…the enablement analysis is simpler and more appropriate.”

Judges Moore and Bryson must have been listening since, on June 26th, a three-judge panel of Moore, Bryson and Wallace invalidated two patents claiming a method to use rapamycin to treat or prevent restenosis by administering an effective amount of rapamycin to a mammal. (U.S. Pat. Nos. 5,516,781 and 5,563,146) on the basis that the specification does not enable one of ordinary skill in the art to practice the asserted claims without undue experimentation. (The decision can be found here.) The arguments by defendants that the specification also failed the WDR were not addressed.

What made it easy for the panel was the fact that Wyeth wanted to assert literal infringement by Abbott et al., that were using two rapamycin analogs, and the parties had agreed that the claim term “rapamycin” was not to be limited to a single compound, sirolimus (Merck 8202) but should be construed to include any anti-restenotic compound containing a macrocyclic triene ring structure, produced by S. hygroscopius. The minute Wyeth et al. agreed to that claim construction, which they must have felt they needed to ensnare the defendants who were using two related sirolimus analogs, Abbott et al. could let the champagne flow. The panel could get to “pick the poison” from s.112(a), and this time they picked non-enablement. Why not? The district court had granted summary judgment of invalidity after marching through the Wands factors, and the panel did the same thing, finding that “practicing the full scope of the invention, measured at the time of filing [1992], would require undue experimentation to both synthesize and screen “tens of thousands of candidates” for anti-restenotic effects. The court noted that “[h]ere the specification similarly [to precedent] discloses only a starting point for further iterative research in an unpredictable and poorly understood field.”

Sound familiar. This language could be taken from the BSC opinion discussed above and, as noted by Judge Gajarsa, it really fits a non-enablement rejection better than a WDR rejection, but that is certainly cold comfort for Wyeth.

What if Wyeth had tried a different approach: “Wide is the gate, but narrow the road.” If the two analogs of sirolimus used by the defendants were unknown or not known to be useful for the recited medical uses in 1992, could Wyeth have argued for a construction of the claim that would limit its literal scope to sirolimus and then argued that the defendants infringed under the doctrine of equivalents? If the analogs used by the defendants were not known as of the filing date of the Wyeth applications, Wyeth would not be estopped from arguing equivalency, since Wyeth could not have included the analogs in its specification in 1992. See Festo. Of course, litigators generally will do almost anything to not have to rely on doe infringement with all its “function, way, result” baggage, but how could things have come out any worse?


One Response to “Wyeth v. Abbott Labs. – Picking Plaintiff’s Poison”

  1. Paul Cole says:

    Those studying this case may wish also to review earlier but parallel litigation involving the 2-hydroxyethyl rapalog called everolimus. The UK case was American Home products v Novartis [2000 R.P.C 547 for which the Court of Appeal opinion is downloadable from the Bailii database:


    The main claim in issue read:

    Use of rapamycin for the preparation of a medicament for inhibiting organ or tissue transplant rejection in a mammal in need thereof

    There was a broadening statement in the description which read:

    “The present invention includes the use of natural and synthetic rapamycin, genetically engineered rapamycin, and all derivatives and prodrugs of rapamycin, such as described in … US Patent Nos. 3929992, 3993749, 4316885 and 4650803.”

    In the outcome the Court of Appeal held that if claim 1 had a broader scope for which the patentees had argued, then the specification would be non-enabling. The requirements for enablement were (a) that the claim should be enabled over its whole scope and (b) the skilled person should not be required to carry out research to ascertain how the invention was to be performed (though he could be required to use appropriate skill and tenacity). In this case, if the patent had covered derivatives of rapamycin (which was what sirolimus was then called), it would have needed to teach how to perform the invention with such derivatives. The specification did not do so because although it told the skilled man where to start, it left him to ascertain by research which derivatives worked, the number of derivatives was vast and the task of ascertaining those which would satisfy the functional part of the claim was vast and correspondingly burdensome. A claim covering derivatives would cover all molecules that would work while leaving it uncertain which ones did and how many of them there were. Such a claim did not reflect a class with a unifying characteristic but was a claim to a number of compounds with the number and identity being left to the skilled person to find out.

    Great minds, as they say, think alike. For a contrary view, it is instructive to read the opinion of Laddie J at first instance. After concluding that “rapamycin” meant the single named chemical, he concluded that there was a distinction between the meaning of the words used in a claim and the meaning of the patent. In the present case the inventor had not made it clear that his intention was only to seek limited protection, but instead there were factors e.g. the statement about derivatives and prodrugs that showed that the intention was to cover more than rapamycin. If the specification were limited to a single compound, it would be virtually valueless because: “It would have disclosed to the art the novel seam of interrelated molecules but have claimed only one of them.” Any reasonable addressee would have been surprised at such a limitation. Instead, the patent covered those derivatives of rapamycin that produced the same type of inhibition of organ rejection as did rapamycin itself. Because there was no sure way of predicting which derivatives would be effective, the inventor should not be forced into a choice between accepting narrow protection and putting forward a wider claim with neatly defined boundaries but where the appearance of certainty was an illusion and the claim was in truth a calculated gamble. “Where the technology makes prediction impossible it cannot be right that the law requires it.”