2009年4月28日火曜日

先行技術文献の引用発明としての適格性

米国CAFC、2008年10月3日判決

1.事件の概要
(第一審原告-第二審控訴人)IMPAX LABORATORIES, INC.
(第一審被告-第二審被控訴人)AVENTIS PHARMACEUTICALS INC.

AVENTIS社が有する米国特許US 5,527,814 (‘814特許)は、リルゾル(riluzole)の筋萎縮性側索硬化症(ALS, 別名ルー・ゲーリック病)の治療用途に関わる発明がクレームされている。

IMPAX社は、自身がANDA承認申請を受けようとするリルゾルを用いるジェネリック医薬が、AVENTIS社の‘814特許を侵害しないことの確認を求めて連邦地裁に提訴した。

IMPAX社は、リルゾルをALSの治療に用いることは先行技術文献である US 5.236,940 (‘940特許)に記載されているから、’814特許は新規性がない旨を主張した。

第一審の連邦地裁は、‘940特許には、‘814特許のクレーム発明は実施可能に記載されておらず、新規性は否定されない旨、判断した。

第二審のCAFCは上記連邦地裁の判断を支持した。

争点は、実施可能に記載されていない先行技術文献の開示が、新規性否定の先行技術としての地位を有するか、という点。

2.判決の要点
“In order to anticipate a claimed invention, a prior art reference must enable one of ordinary skill in the art to make the invention without undue experimentation.”
“In other words, the prior art must enable the claimed invention.”
“The “undue experimentation” component of that equation examines (1) the quantity of experimentation; (2) the amount of direction or guidance present; (3) the presence or absence of working examples; (4) the nature of the invention; (5) the state of the prior art; (6) the relative skill of those in the art; (7) the predictability or unpredictability of the art; and (8) the breadth of the claims.”

“The district court found that excessive experimentation would have been necessary to practice the invention. Specifically the trial court opined that formula I of the alleged prior art discloses hundreds or thousands of compounds and several diseases. Moreover, nothing in the ’940 patent would direct one skilled in the art to recognize that riluzole could be used to treat ALS. The trial court rejected the notion that “the mere mention of riluzole is sufficient to put one skilled in the art in the possession of the claimed invention.””

“The district court also did not find the dosage information in the disclosure to teach a proper treatment. Instead the trial court noted that “the dosage guidelines are broad and not specific to any of the hundreds of formula I compounds of the claimed invention or to any of the listed diseases.””

“Moreover, the '940 patent ties the dosing information to “the compounds of the invention” and specifically excludes riluzole from the invention.”
“Finally, the trial court also noted the absence of working examples. “

“In view of these findings, the district court found that one of ordinary skill in the pharmaceutical arts would have needed extensive experimentation to link riluzole with the treatment of ALS. The district court then reached the ultimate conclusion that the ’940 patent does not enable claims 1-5 of the ’814 patent and thus, it is not anticipatory.
This court does not find error, let alone clear error, in the district court’s factual findings. Weighing the Wands factors, the trial court's findings properly support its conclusion that an ordinarily skilled artisan would have needed to experiment unduly to gain possession of the invention. As shown by the trial court, the '940 patent's dosage guidelines are broad and general without sufficient direction or guidance to prescribe a treatment regimen. The alleged prior art also contains no working examples. Finally, nothing in the '940 patent would have led one of skill in the art to identify riluzole as a treatment for ALS. In sum, each component of the claimed invention—identifying riluzole as a treatment for ALS and devising dosage parameters—would require undue experimentation based on the teachings of the '940 patent. Because the ’940 patent does not enable a person of ordinary skill in the art to treat ALS with riluzole, it does not anticipate claims 1-5 of the ’814 patent.”


3.ブログ管理人コメント
発明を完成させるために過度の実験を要する引用文献の開示は、当該発明の新規性を否定しない場合があることが判断された。

通常は、実施可能要件(米国特許法112条第1パラグラフ)を満たしているかの判断の指標として使われるWands の要件が、先行技術の開示が実施可能に記載されているかの判断において用いられている。