• Federal Circuit Remands Sequenom Down Syndrome Test Platform Patent for Consideration Under Myriad
  • August 14, 2013 | Author: Courtenay C. Brinckerhoff
  • Law Firm: Foley & Lardner LLP - Washington Office
  • In Aria Diagnostics, Inc. v. Sequenom, Inc., the Federal Circuit vacated and remanded the district court’s decision denying Sequenom’s motion for a preliminary injunction relating to a patent covering the non-invasive Sequenom Down Syndrome test. The Federal Circuit found that the district court had “incorrectly interpreted the asserted claims and improperly balanced factors regarding issuance of a preliminary injunction.” The Federal Circuit also directed the district court to reexamine the patent eligibility issues in view of the Myriad Supreme Court decision, but I do not understand how the claims at issue could be invalid under 35 USC § 101.

    The Patent at Issue

    The patent at issue was U.S. Patent 6,258,540, which is owned by Isis Innovation Limited and exclusively licensed to Sequenom.

    The Federal Circuit describes the invention as follows:

    The ’540 patent discloses methods to identify fetal genetic defects by analyzing ... maternal plasma or serum. The ’540 patent discloses that non-nucleated free floating fetal DNA (the cffDNA) exists in maternal blood. ... The specification explains that not only does analysis of cffDNA permit more efficient determination of genetic defects (for example, trisomy of chromosome 21) but that a pregnant woman carrying a fetus with certain genetic defects will have more cffDNA in her blood than do women with normal fetuses. ... In other words, the ’540 patent claims methods to detect fetal genetic characteristics by analyzing cffDNA obtained from a maternal blood sample. These new tests presented fewer risks and a more dependable rate of abnormality detection.

    Claim 1 recites:

    A method for detecting a paternally inherited nucleic acid of fetal origin performed on a maternal serum or plasma sample from a pregnant female, which method comprises amplifying a paternally inherited nucleic acid from the serum or plasma sample and detecting the presence of a paternally inherited nucleic acid of fetal origin in the sample.

    (The claim terms involved in the claim construction dispute are highlighted.)

    The District Court Proceedings

    Aria Diagnostics, Inc. (now known as Ariosa Diagnostics, Inc.) brought a declaratory judgment action seeking a declaration that its “Harmony” test did not infringe the ‘540 patent. Sequenom brought an infringement counterclaim and sought a preliminary injunction. The district court construed the claims, found a substantial question of non-infringement, considered the other factors pertinent to a preliminary injunction inquiry, and denied the preliminary injunction. Sequenom appealed.

    The Federal Circuit Decision

    Chief Judge Rader authored the opinion for a unanimous panel of the Federal Circuit. (Judges Dyk and Reyna also were on the panel.)

    Claim Construction

    At the outset, the decision notes debate as to whether the Federal Circuit should “definitively construe” claims or apply a “more relaxed” standard of review at the preliminary injunction stage. However, the Federal Circuit avoids deciding this issue, finding that the district court’s claim construction was incorrect under either standard of review.

    The district court had construed “paternally inherited nucleic acid” as meaning “DNA sequence known [in advance] to be received only from the father which is not possessed by the mother.”

    (The Federal Circuit explains that the district court did not expressly include the bracketed language in its claim construction, but the parties agreed that the district court had read that limitation into the claims such that “infringement can only occur after a user knows the father’s gene sequence (for example, through genotyping).”)

    The Federal Circuit found no basis for the “known [in advance]” limitation, in any of the claims, specification, or prosecution history. To the contrary, the Federal Circuit found that one example where maternal, but not paternal, RhD gene status was determined weighed against the district court’s claim construction. The Federal Circuit also considered the prosecution history of a subsequent continuation application, but found no arguments that even implied that “paternally inherited nucleic acid” must be “known [in advance].”

    The district court had construed “amplifying” to mean “increasing the concentration of a paternally inherited nucleic acid relative to the other DNA in the sample.” The Federal Circuit found no basis for the “relative” aspect of this definition. For example, the Federal Circuit noted that “[t]he claim does not state that paternally inherited nucleic acid is ‘selectively’ or ‘only’ amplified.” The Federal Circuit also noted that the specification discussed the amplification of DNA separately from the selective enrichment of fetal DNA.

    Having found that the district court’s claim construction was erroneous, the Federal Circuit reversed its conclusion that Ariosa had raised a substantial question of noninfringement.

    Preliminary Injunction

    With regard Sequenom’s motion for a preliminary injunction, the Federal Circuit explained:

    [I]f the district court finds no substantial question of validity or infringement, it must address the traditional equitable factors for a preliminary injunction. ... [I]n addition to showing the likelihood of success on the merits, Sequenom must show it likely will suffer irreparable harm, that the balance of equities tips in its favor, and that an injunction is in the public interest.

    The Federal Circuit’s guidance on the “irreparable harm” and “public interest” factors are interesting.

    On irreparable harm. the Federal Circuit criticized the district court for finding that “price and market erosion would occur,” but reasoning that these harms “were not irreparable,” based on Sequenom’s arguments that its own tests “would set new standards of care.” According to the Federal Circuit, “[i]n the face of that kind of universal assumption, patents would lose their character as an exclusive right as articulated by the Constitution and become at best a judicially imposed and monitored compulsory license.”

    On public interest, “the district court reasoned that the public interest favored denial of the preliminary injunction” because Ariosa marketed its test to low and high-risk women, while “Sequenom marketed its tests only to women over 35 and at high risk both of having a fetus with Down’s Syndrome and of losing a fetus through invasive testing.” However, the Federal Circuit had taken “judicial notice” that “an expert organization had warned that cffDNA tests should not, yet, be used in low risk women,” citing Am. Coll. of Obstetricians and Gynecologists Comm. on Genetics, Noninvasive Prenatal Testing for Fetal Aneuploidy, Op. No. 545 (Dec. 2012). The Federal Circuit advised the district court to “consider this and any other evidence pertaining to the public interest anew.”

    How might this guidance play out in the pending litigation between Myriad and Ambry?

    Where Is the Patent Eligibility Issue Here?

    When I first saw that this case related to a diagnostic method, I thought it would focus on 35 USC § 101 issues, but then I read the claims. I certainly do not find any “natural phenomenon” that might bring them under Mayo v. Prometheus, or any “isolated DNA” that might bring them under Myriad. So, why did the Federal Circuit not criticize the district court’s finding that “there was a substantial question over whether the subject matter of the asserted claims was to eligible subject matter,” but instead remanded “for the district court to examine subject matter eligibility [under the Myriad Supreme Court decision] in the first instance”?