PTAB Denies Institution of IPR Based on Petitioner’s Failure to Rebut Strong Evidence of Objective Indicia of Non-Obviousness

Oct 6, 2016

Reading Time : 1 min

The patents under review are directed to methods of reducing the risk of adverse events, such as pulmonary edema, associated with treating a patient with inhaled nitric oxide gas. The specification of the patents describes a study, INOT22 that was conducted to assess the safety and efficacy of INOMax, an FDA-approved drug for treating neonates who have hypopoxic respiratory failure associated with evidence of pulmonary hypertension. Based on the results of this study, the inventors determined that patients with pre-existing left ventricular dysfunction (LVD) had an increased risk of experiencing serious adverse events, such as pulmonary edema, upon administration of INOMax. Therefore, the patents have a common limitation, which excludes a child from treatment with inhaled nitric oxide if the child has LVD.

The petitioners argued that the patents are obvious based on the disclosures in three references that were not presented in the prior set of petitions. In both the prior and current sets of petitions, the PTAB found that the INOT22 study provides compelling evidence that the claims were not obvious to a person of skill in the art because several leading experts in the field designed this study without excluding children with pre-existing LVD. The PTAB found that although the petitioners’ argument that the newly added references teach that children and neonates with LVD should be excluded from treatment, petitioners failed to rebut the evidence of secondary considerations because they do not explain why many experts in the field designed studies that did not exclude patients with pre-existing LVD if it were obvious to do so. In addition, the PTAB found that the newly added prior art references should have been known to Praxair when it filed its original petitions. Therefore, the PTAB declined to institute IPR reviews for any of the claims of the challenged patents.

Praxair Distribution, Inc. v. Mallinckrodt Hospital Products, Nos. IPR2016-00777, IPR2016-00778, IPR2016-00779, IPR2016-00780, Paper 10 (PTAB, Sep. 22, 2016).

Share This Insight

Previous Entries

IP Newsflash

July 22, 2026

The Court of Federal Claims recently denied the United States’ motion to dismiss a patent infringement suit related to production of a COVID-19 vaccine. The court held that it had jurisdiction because the plaintiff filed its claim there before it filed a parallel suit in a district court and because it adequately pleaded the government’s involvement.

...

Read More

IP Newsflash

July 13, 2026

In a precedential and sua sponte Director Review decision, USPTO Director Squires recently vacated three related institution decisions nearly six months after institution where a district court later found the challenged claims invalid. Because the fourteen-day deadline to request Director Review of the institution decisions had passed, the Director used this opportunity to formally extend the deadline in two ways. First, he extended the fourteen-day deadline under 37 C.F.R. § 42.75(c)(1) to thirty days, which “puts requests for Director Review of decisions to institute trial on equal footing to requests for Director Review of final decisions or decisions not to institute trial.” Second, he outlined certain “exceptional circumstances” that warrant a further extension of the deadline to account for changes in the case that “surface after the deadline.” In the case at hand, the Director found the district court’s invalidity finding to be such an “exceptional circumstance” and ultimately initiated review and vacated the institution decisions on that basis.

...

Read More

IP Newsflash

June 5, 2026

The Supreme Court unanimously held that for a complaint of induced infringement, a patent owner must allege that the accused infringer took affirmative, not passive, steps to encourage direct infringement. Thus, where a generic drug has a skinny label, to induce infringement of the carved-out patented use of the drug, the generic company must have taken steps that were designed to cause others to perform the patented use, not just steps that could cause such conduct.

...

Read More

IP Newsflash

May 07, 2026

The Northern District of Illinois granted a summary judgment motion of no invalidity based on indefiniteness because the qualitative terms like “sufficiently slow” and “desired period of time” were definite when viewed in light of the surrounding claim language and specification.

...

Read More

© 2026 Akin Gump Strauss Hauer & Feld LLP. All rights reserved. Attorney advertising. This document is distributed for informational use only; it does not constitute legal advice and should not be used as such. Prior results do not guarantee a similar outcome. Akin is the practicing name of Akin Gump LLP, a New York limited liability partnership authorized and regulated by the Solicitors Regulation Authority under number 267321. A list of the partners is available for inspection at Eighth Floor, Ten Bishops Square, London E1 6EG. For more information about Akin Gump LLP, Akin Gump Strauss Hauer & Feld LLP and other associated entities under which the Akin Gump network operates worldwide, please see our Legal Notices page.