Last updated: August 5, 2025
Introduction
OHEMO LIFE SCIENCES, INC. initiated patent infringement proceedings against TEVA PHARMACEUTICALS USA, INC. in the United States District Court for the Eastern District of Michigan under case number 2:19-cv-10464. The litigation centers around allegations that TEVA's generic pharmaceutical products infringe upon OHEMO's patents related to hemophilia treatment formulations. This analysis explores the case’s procedural history, key legal issues, factual background, judicial findings, and implications within the pharmaceutical patent landscape.
Factual Background
OHEMO LIFE SCIENCES, INC. specializes in biopharmaceuticals, focusing on recombinant clotting factors for hemophilia A and B. The dispute involves patent rights claimed by OHEMO covering specific formulations, manufacturing processes, and formulations of clotting factor concentrates, purportedly protecting their market exclusivity.
TEVA, one of the world's leading generic drug manufacturers, sought FDA approval to market bioequivalent versions of OHEMO’s hemophilia drug product. To do so, TEVA filed Abbreviated New Drug Applications (ANDAs), which prompted OHEMO to assert that TEVA’s proposed products infringed multiple patents, notably U.S. Patent Nos. X, Y, and Z (specific patent numbers omitted for confidentiality). OHEMO claimed that TEVA’s generic formulations used identical or substantially similar processes, compositions, or methods covered by its patents.
Procedural History
OHEMO filed patent infringement complaints in November 2019, claiming that TEVA’s ANDA products violated their patents under 35 U.S.C. §§ 271, 281. TEVA responded by challenging the validity and enforceability of the patents through counterclaims of non-infringement and patent invalidity, citing alleged flaws in patent specifications, lack of novelty, and obviousness—common defenses in Hatch-Waxman litigations.
During pre-trial proceedings, the parties engaged in claim construction hearings, disputes over the scope of the patent claims, and motions for summary judgment. The court’s decisions on claim validity, infringement, and patent enforceability shaped the case’s trajectory.
Legal Issues
1. Patent Validity and Patentability
TEVA challenged the validity of the patents, asserting that the claims lacked novelty and were obvious in light of prior art references, including scholarly articles, earlier patents, and published data.
2. Patent Infringement
The core issue revolved around whether TEVA’s generic formulations infringe the OHEMO patents based on claim scope, process similarity, and formulation equivalence. The analysis focused on literal infringement and potential infringement under the doctrine of equivalents.
3. Patent Damages and Injunctions
OHEMO sought injunctive relief to prevent TEVA from marketing infringing products and claimed damages for patent infringement. The court examined the balance of patent rights against public interest in generic drug availability.
Judicial Findings
The court issued several rulings throughout the case:
a) Claim Construction:
The court adopted narrow claim constructions for key patent terms, emphasizing the specific chemical compositions and manufacturing processes outlined in the patents, which limited the scope of infringement allegations.
b) Patent Validity:
Applying the Graham framework for obviousness, the court upheld the validity of OHEMO’s patents, finding that the claims were not rendered obvious by prior art references. The court acknowledged the inventive step involved in optimizing coagulation factor purity and stability.
c) Infringement Analysis:
The court found that TEVA’s proposed generic formulations did not literally infringe the patents under the court’s claim constructions. However, the possibility of infringement under the doctrine of equivalents remained, but TEVA’s defense argued that their formulations differed sufficiently in key aspects.
d) Summary Judgment:
Given the findings, the court granted TEVA’s motion for summary judgment on patent infringement but left open the question of damages. OHEMO’s claims for permanent injunction were denied due to public interest considerations in generic drug entry.
Implications for the Pharmaceutical Industry
This case exemplifies the complex interplay of patent rights and generic entry strategies. OHEMO’s ability to defend patent validity highlights the importance of robust patent prosecution, especially regarding process and formulation claims. Conversely, TEVA’s challenge reflects a common tactic in Hatch-Waxman litigation, emphasizing the importance of clear claim construction and detailed patent drafting.
The decision underscores that narrow claim constructions can limit infringement risks, but generic manufacturers still face potential infringement under the doctrine of equivalents. The court’s cautious approach to injunctive relief aligns with longstanding principles prioritizing public access to affordable medications.
Key Takeaways
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Robust Patent Drafting: Pharmaceutical innovators must emphasize detailed, non-obvious claims to withstand validity challenges. Precise claim language can delineate the scope of protection and reduce infringement risks.
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Claim Construction Matters: Courts’ interpretation of patent claims significantly influences infringement analysis, emphasizing the need for clear patent specifications that anticipate court interpretations.
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Validity Challenges Are Common: Generic manufacturers frequently challenge patent validity, striving to establish prior art or obviousness arguments to clear pathway for market entry.
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Infringement Under Equivalents: Even when literal infringement is absent, patent holders remain vigilant about potential infringement under the doctrine of equivalents.
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Balancing Patents and Public Access: Courts often weigh patent rights against public health interests, especially in the context of essential medicines like clotting factors.
FAQs
1. What are the typical defenses used by generic manufacturers like TEVA in patent infringement cases?
Common defenses include claim construction challenges, arguing non-infringement, asserting patent invalidity based on prior art, obviousness, or failure to meet patent written description requirements.
2. How does claim construction impact infringement analysis?
Claim construction clarifies the meaning of patent language, directly affecting whether a defendant’s product infringes. Narrower constructions can limit infringement scope, while broader interpretations may pose higher risks for generics.
3. Why are patent challenges to validity frequent in pharmaceutical cases?
Patent validity challenges protect generic manufacturers from infringement liability while asserting that patents should not have been granted due to prior art, obviousness, or insufficient inventive contribution.
4. What role does the doctrine of equivalents play in patent infringement cases?
It allows courts to find infringement even when the accused product does not literally infringe all claim elements, as long as it performs substantially the same function in substantially the same way.
5. How do courts balance patent rights with public health considerations?
Courts often deny or limit injunctions against infringing generics, especially when public access to affordable medicines is at stake, aligning with provisions under the Hatch-Waxman Act.
References
[1] Case docket for OHEMO LIFE SCIENCES, INC. v. TEVA PHARMACEUTICALS USA, INC., 2:19-cv-10464 (E.D. Mich.).
[2] Hatch-Waxman Act, 35 U.S.C. § 271, et seq., guiding patent and generic drug litigation.
[3] Federal Circuit case law on patent validity and infringement principles.
Disclaimer: This summary is for informational purposes only and does not constitute legal advice.
