REGENXBIO v. Sarepta: AAV Vector Patent Case Stayed for PTAB Review
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📋 Case Summary
| Case Name | REGENXBIO, Inc. and The Trustees of the University of Pennsylvania v. Sarepta Therapeutics, Inc., et al. |
| Case Number | 1:23-cv-00667 (D. Del.) |
| Court | U.S. District Court for the District of Delaware |
| Duration | June 20, 2023 – March 20, 2024 274 days |
| Outcome | Case Stayed — PTAB IPR Pending |
| Patents at Issue | |
| Accused Products | Methods of increasing the function of an AAV vector (used in gene therapy development/production) |
Case Overview
When a district court patent case collides with a parallel PTAB proceeding, the litigation strategy shifts entirely. That is precisely what unfolded in REGENXBIO, Inc. and The Trustees of the University of Pennsylvania v. Sarepta Therapeutics, Inc., et al., Case No. 1:23-cv-00667, before the U.S. District Court for the District of Delaware.
Filed on June 20, 2023, and administratively closed on March 20, 2024 — just 274 days later — this AAV vector patent infringement action was stayed pending inter partes review (IPR) proceedings before the Patent Trial and Appeal Board (PTAB). The case centers on U.S. Patent No. 11,680,274 B2, covering methods of increasing the function of an AAV (adeno-associated virus) vector, a technology at the heart of a rapidly expanding gene therapy market.
For patent litigators, IP professionals, and R&D leaders in the gene therapy space, this case offers a timely reminder of how PTAB proceedings can reshape — and temporarily freeze — district court litigation, even in high-stakes biotech disputes.
The Parties
⚖️ Plaintiffs
REGENXBIO is a leading clinical-stage gene therapy company focused on licensing AAV vector technology. The Trustees of the University of Pennsylvania reflect the academic origins of this foundational AAV technology.
🛡️ Defendants
Sarepta Therapeutics is a commercial-stage rare disease company with a significant gene therapy pipeline. Catalent, Inc. (CDMO) was also named as a defendant.
The Patent at Issue
This case involves U.S. Patent No. 11,680,274 B2, covering methods of increasing the function of an AAV vector. This technology is broadly applicable to gene therapy manufacturing and delivery platforms.
- • US 11,680,274 B2 — Methods of increasing AAV vector function
Developing AAV-based therapies?
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The Verdict & Legal Analysis
Outcome
The case was administratively closed on March 20, 2024, via a stay order. No merits judgment, damages award, or injunctive relief was issued. The case remains subject to reopening upon resolution of the parallel PTAB IPR proceedings concerning U.S. Patent No. 11,680,274 B2.
No damages figure is available, as the case did not reach trial or settlement disclosure. Injunctive relief was neither granted nor denied on the merits.
Key Legal Issues
The stay was entered due to pending inter partes review at the PTAB — a proceeding by which any party can challenge the validity of an issued patent on grounds of novelty and obviousness based on prior art patents and printed publications. Courts routinely stay district court proceedings when a PTAB IPR is pending, applying a three-factor balancing test:
- Whether a stay simplifies issues for trial
- Whether discovery is complete and a trial date set
- Whether a stay would unduly prejudice the non-moving party
In this instance, the court found sufficient grounds to stay and administratively close the case at the pre-trial stage. The early-stage posture — no claim construction order or summary judgment rulings appear in the record before closure — suggests the IPR petition was filed and granted relatively promptly after district court proceedings commenced.
This case exemplifies the “PTAB as leverage” strategy that has become standard defensive practice in high-value biotech patent litigation. By securing a stay, Sarepta effectively paused the district court action — including discovery obligations, potential preliminary injunction proceedings, and litigation costs — while PTAB evaluates the foundational validity of the asserted patent claims.
Freedom to Operate (FTO) Analysis
This case highlights critical IP risks in AAV gene therapy. Choose your next step:
📋 Understand This Case’s Impact
Learn about the specific risks and implications from this litigation.
- View all related patents in the AAV vector space
- See which companies are most active in gene therapy IP
- Understand patent claim scope and limitations
🔍 Check My Product’s Risk
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- Input your AAV vector details or manufacturing process
- AI identifies potentially blocking patents (e.g., REGENXBIO’s portfolio)
- Get actionable risk assessment report
High Risk Area
AAV vector optimization & manufacturing
Dense Prior Art
Expect IPR challenges in biotech
PTAB Outcomes
Directly impact commercial risk
✅ Key Takeaways
Administrative stays pending PTAB IPR are a viable early-stage defensive tool in biotech patent cases, effectively resetting the litigation timeline.
Search related case law →Delaware District Court remains a preferred venue for high-value AAV/gene therapy patent disputes.
Explore court analytics →CDMO defendants represent an expanding category of enforcement targets in biotech patent litigation, covering the entire supply chain.
Identify supply chain risks →Frequently Asked Questions
U.S. Patent No. 11,680,274 B2 (Application No. 16/368,758), covering methods of increasing the function of an AAV vector, a core gene therapy technology.
The District of Delaware stayed the case on March 20, 2024, due to pending inter partes review proceedings before the PTAB challenging the validity of the asserted patent. The case may be reopened upon PTAB resolution.
The case highlights that AAV vector technology patents face dual-track litigation risk — district court infringement exposure and PTAB validity challenges simultaneously — a dynamic all gene therapy developers and CDMOs must factor into IP risk management strategies.
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References
- USPTO Patent Center — U.S. Patent No. 11,680,274 B2
- PACER Case No. 1:23-cv-00667 (D. Del.)
- PTAB Docket Search
- Cornell Legal Information Institute — 35 U.S.C. § 311 (Inter Partes Review)
- PatSnap — IP Intelligence Solutions for Law Firms
This article is for informational purposes only and does not constitute legal advice. All case information is drawn from publicly available court records. For platform capabilities, visit PatSnap.