Last updated: August 8, 2026
Allergan Sales, LLC v. Teva Pharmaceuticals USA, Inc., No. 1:16-cv-01114-RGA, was a Hatch-Waxman case involving Teva's proposed generic version of Restasis, Allergan's cyclosporine ophthalmic emulsion for chronic dry-eye disease. The case centered on U.S. Patent Nos. 8,629,111 and 9,248,191. The District of Delaware ruled that the asserted claims were invalid for obviousness, eliminating the principal patent barrier to Teva's ANDA product. The Federal Circuit affirmed the judgment in 2019. [1][2]
What drug and patents were involved in Allergan v. Teva?
The case involved Restasis, a topical ophthalmic emulsion containing cyclosporine 0.05%. Allergan marketed Restasis for increasing tear production in patients whose tear production was suppressed because of ocular inflammation associated with keratoconjunctivitis sicca.
| Item |
Case information |
| Brand |
Restasis |
| Active ingredient |
Cyclosporine |
| Dosage form |
Ophthalmic emulsion |
| Strength |
0.05% |
| NDA holder |
Allergan |
| Defendant |
Teva Pharmaceuticals USA, Inc. |
| Court |
U.S. District Court for the District of Delaware |
| Civil action |
No. 1:16-cv-01114-RGA |
| Judge |
Richard G. Andrews |
| Filing basis |
Teva ANDA filing under the Hatch-Waxman Act |
| Principal patents |
U.S. Patent Nos. 8,629,111 and 9,248,191 |
| Trial result |
Asserted claims held invalid for obviousness |
| Federal Circuit result |
District court judgment affirmed |
The patents claimed aspects of the cyclosporine ophthalmic emulsion, including the use of a formulation containing cyclosporine, castor oil, polysorbate 80, carbomer, and a hypertonicity-adjusting agent. The asserted claims were directed to formulation composition and use rather than to cyclosporine as a molecule. Cyclosporine itself was long known before Restasis was developed.
What patents protected Restasis in the Teva litigation?
The two principal patents at issue were:
| Patent |
Subject matter |
Litigation treatment |
| U.S. Patent No. 8,629,111 |
Cyclosporine ophthalmic emulsion and related composition claims |
Asserted; claims held invalid as obvious |
| U.S. Patent No. 9,248,191 |
Related cyclosporine ophthalmic emulsion claims |
Asserted; claims held invalid as obvious |
The '111 patent issued in January 2014. The '191 patent issued in February 2016. Both patents were listed in the FDA's Approved Drug Products with Therapeutic Equivalence Evaluations, commonly known as the Orange Book, in connection with Restasis. [3]
The patents did not create exclusivity over all ophthalmic uses of cyclosporine. Their commercial value depended on the formulation's ability to deliver cyclosporine to the eye as an emulsion with adequate physical stability and tolerability.
Allergan later asserted additional Restasis patents in related generic-drug litigation, including U.S. Patent Nos. 9,669,069 and 9,675,677. Those later patents were not the central patents adjudicated in the initial Teva trial and should not be treated as part of the same final invalidity judgment without reviewing the particular later action.
When did Allergan sue Teva, and what triggered the case?
Allergan filed the action after Teva submitted an abbreviated new drug application seeking approval to market a generic cyclosporine ophthalmic emulsion. Teva's ANDA included a Paragraph IV certification challenging the validity or enforceability of Allergan's Orange Book-listed patents.
A Paragraph IV certification is a statutory representation that a listed patent is invalid, unenforceable, or will not be infringed by the proposed generic product. Allergan's infringement suit triggered the Hatch-Waxman 30-month stay, preventing FDA approval of Teva's ANDA for a statutory period unless the stay was shortened or a court resolved the dispute earlier. [4]
The case was part of a broader wave of Restasis litigation involving several generic applicants. The commercial objective of each defendant was to obtain FDA approval for a lower-priced cyclosporine ophthalmic emulsion after overcoming Allergan's formulation patents.
What did the District of Delaware decide?
The district court held after trial that the asserted claims of the '111 and '191 patents were invalid for obviousness under 35 U.S.C. § 103. The court concluded that the prior art, combined with the knowledge and motivation of a person skilled in ophthalmic drug formulation, made the claimed formulation and treatment approach obvious. [1]
The court's reasoning focused on several points:
- Cyclosporine was an established immunosuppressive compound with known ophthalmic applications.
- Emulsion formulations were known delivery vehicles for poorly water-soluble drugs.
- The relevant excipients and formulation techniques were disclosed in the prior art.
- The claimed formulation did not demonstrate an unexpected result sufficient to overcome the obviousness case.
- Allergan's evidence of commercial success and other secondary considerations did not outweigh the prior-art evidence.
The decision rejected the proposition that formulation difficulty alone established nonobviousness. The relevant question was whether the claimed combination would have been an obvious formulation choice for a skilled artisan with a reasonable expectation of success.
The decision was commercially significant because the formulation, rather than the active ingredient, was the principal remaining patent barrier to generic competition.
How did the Federal Circuit rule in Allergan v. Teva?
The Federal Circuit affirmed the district court's invalidity judgment in 2019. The appellate court upheld the obviousness analysis and rejected Allergan's challenges to the district court's findings regarding motivation to combine, reasonable expectation of success, and secondary considerations. [2]
The Federal Circuit treated the district court's factual findings under the applicable clear-error standard and reviewed the ultimate obviousness conclusion without deference. It found no reversible error in the trial court's treatment of the prior art or Allergan's objective-indicia evidence.
The affirmance left the asserted claims of the '111 and '191 patents unavailable to block Teva or other generic applicants. It also reduced the litigation value of related Restasis formulation patents because the Federal Circuit's reasoning addressed the core technical theory behind Allergan's patent estate.
Did Allergan transfer Restasis patents to the Saint Regis Mohawk Tribe?
Yes. In 2017, Allergan transferred certain Restasis patents to the Saint Regis Mohawk Tribe and received an exclusive license back. Allergan pursued the transaction in an effort to invoke the tribe's sovereign immunity in inter partes review proceedings at the Patent Trial and Appeal Board.
The transaction generated separate administrative and appellate litigation. The Federal Circuit held that tribal sovereign immunity did not prevent the PTAB from proceeding with inter partes review because the agency could continue the proceeding without the tribe as a necessary party. [5]
The sovereign-immunity strategy did not prevent the Delaware district court from adjudicating the patent claims against Teva. The invalidity judgment in the district court therefore remained a direct threat to the enforceability of the transferred patents.
What was the Orange Book status of Restasis?
Restasis was approved under NDA No. 050790. The product's original five-year new chemical entity exclusivity period had expired before the Teva litigation. The remaining protection came principally from listed patents and related regulatory barriers.
| Regulatory or patent barrier |
Effect |
| NCE exclusivity |
Expired before the 2016 Teva suit |
| Orange Book patents |
Created the basis for Paragraph IV litigation |
| 30-month stay |
Delayed FDA approval after Allergan's infringement suit |
| Formulation patents |
Main legal barrier to generic entry |
| Patent invalidity judgment |
Removed the principal asserted barrier in the Teva case |
The FDA later approved generic cyclosporine ophthalmic emulsion products. Mylan Pharmaceuticals received approval for a generic Restasis product in 2022, and other applicants pursued approval through the ANDA pathway. [6]
FDA approval of a generic product does not itself establish that every Restasis patent is invalid. Approval depends on the applicant's certification and the status of the applicable patents. The Teva judgment, however, materially weakened the enforceability of the two patents at the center of the case.
What was the patent expiration date for the Restasis patents?
The relevant patents had expiration dates in the 2024 period, subject to any applicable patent-term adjustment or terminal-disclaimer effects. The practical value of those dates was reduced by the invalidity judgment.
Patent expiration analysis must distinguish between:
- the nominal expiration date;
- patent-term adjustment;
- patent-term extension;
- terminal disclaimers;
- claim-by-claim invalidity;
- and whether a later patent remains enforceable.
For the '111 and '191 patents, invalidity was more important than nominal expiration because an invalid claim cannot be used to exclude generic competition even before its scheduled expiration date.
What formulation patents protected Restasis?
Restasis protection was primarily formulation-based. The commercial formulation used cyclosporine in an emulsion designed to improve ocular delivery of a water-insoluble active ingredient.
The principal technical issues were:
- dispersion of cyclosporine in the emulsion;
- emulsion stability;
- particle or droplet characteristics;
- ocular tolerability;
- preservation and packaging;
- delivery of a therapeutically useful amount of cyclosporine;
- and avoidance of excessive irritation.
The case demonstrates the limits of formulation patent protection where the active ingredient and general dosage form are already known. A formulation patent must distinguish the claimed combination from the prior art through structural limitations, process limitations, or reliable unexpected results.
How strong was Allergan's Restasis patent estate?
The estate was commercially valuable but legally vulnerable. Its strength differed across patent categories.
| Patent category |
Strength assessment |
| Cyclosporine molecule patents |
Minimal or nonexistent; molecule was long known |
| Broad ophthalmic-use claims |
Limited by earlier cyclosporine and dry-eye disclosures |
| Restasis formulation claims |
Significant commercial relevance but vulnerable to obviousness attacks |
| Later formulation patents |
Potentially useful, but dependent on claim scope and separate litigation outcomes |
| Method-of-use claims |
Narrower protection and vulnerable where the indication or dosing regimen was known |
| Manufacturing and process claims |
Could create additional barriers if difficult to design around, but not the principal issue in the Teva judgment |
Allergan's strongest position was the combination of an established product, physician familiarity, regulatory approval, and a formulation that was difficult to duplicate commercially. The district court's decision showed that commercial success did not cure weaknesses in the underlying obviousness case.
What generic entry risks existed for Restasis?
The main generic-entry risks were formulation substitution, regulatory approval, and patent invalidity.
Formulation substitution
A generic applicant could seek approval for a formulation that was pharmaceutically equivalent without copying every aspect of the Restasis formulation. Small differences in excipients, manufacturing conditions, droplet characteristics, or packaging could affect infringement exposure.
Paragraph IV litigation
A Paragraph IV certification allowed the generic applicant to challenge Allergan's listed patents before launch. Allergan's response created the statutory 30-month stay, but the stay did not guarantee market exclusivity if the patents were invalidated.
At-risk launch
After an invalidity judgment, a generic applicant may have a stronger basis to launch before patent expiration, subject to appeal, injunction, and separate patents. The commercial risk depends on whether the judgment covers all relevant listed patents and whether another patent can support an injunction.
Regulatory substitution
Cyclosporine ophthalmic emulsion products may face substitution and formulary questions even after FDA approval. Generic uptake depends on therapeutic-equivalence ratings, payer policies, physician prescribing, pharmacy substitution rules, and product availability.
Did the case involve a settlement agreement?
The reported Teva litigation culminated in a district court invalidity judgment followed by Federal Circuit affirmance, rather than a publicly reported launch-date settlement that controlled the final result. Other Restasis defendants negotiated separate settlements or commercial arrangements, and those agreements should not be attributed to Teva without a case-specific docket or settlement filing.
The distinction matters because a settlement can preserve branded exclusivity through a negotiated generic-entry date, while an invalidity judgment removes the patent barrier on legal grounds.
What was the commercial impact of the Teva judgment?
Restasis was a major Allergan product, with annual sales exceeding $1 billion during the period when generic competition was approaching. Allergan reported Restasis sales of approximately $1.5 billion in 2016 before generic entry materially affected the franchise. [7]
The judgment exposed a large revenue stream to generic erosion. The impact was not necessarily immediate because:
- Teva still needed FDA approval;
- other Restasis patents could remain in dispute;
- product manufacturing and launch capacity affected timing;
- generic applicants could face separate litigation;
- and branded, authorized-generic, or alternative cyclosporine products could compete.
The decision also affected Allergan's broader intellectual-property strategy. The later transfer of patents to the Saint Regis Mohawk Tribe reflected the commercial importance of preserving Restasis exclusivity after conventional patent litigation became unfavorable.
How does Restasis patent risk compare with biologic and generic drug risk?
Restasis is a small-molecule drug regulated through the ANDA pathway, not a biologic regulated through the biosimilar pathway. Biosimilar risk is therefore not directly applicable.
| Issue |
Restasis |
Biologic |
| FDA pathway |
ANDA |
351(k) biosimilar application |
| Main challenge |
Generic equivalence and patent validity |
Biosimilarity, interchangeability, and patent dance |
| Patent dispute |
Paragraph IV |
Biologics Price Competition and Innovation Act procedures |
| Manufacturing barrier |
Moderate; formulation and emulsion reproducibility |
Often high; complex biologic manufacturing |
| Substitution |
Governed by generic equivalence rules |
Depends on interchangeability designation and state law |
For Restasis, the principal barrier was intellectual property around a reproducible ophthalmic emulsion. For biologics, manufacturing complexity and regulatory comparability usually create a more substantial non-patent barrier.
What litigation lessons does Allergan v. Teva provide?
The case produced several strategic lessons for branded-drug patent owners and generic applicants:
- A formulation patent must be drafted around technically meaningful distinctions, not simply a known active ingredient in a conventional dosage form.
- Objective indicia of nonobviousness require a strong nexus to the claimed features.
- Commercial success is less persuasive when the evidence does not isolate the patented formulation from brand recognition, regulatory approval, or marketing.
- A Paragraph IV challenge can convert a formulation dispute into a full validity trial before product launch.
- Patent transfers to sovereign entities do not necessarily prevent PTAB review or district-court adjudication.
- Invalidity of core formulation patents can undermine later enforcement strategies based on closely related claims.
- Generic entry risk must be assessed across the entire Orange Book listing, not through one patent or one lawsuit.
Key Takeaways
- Allergan sued Teva over a Paragraph IV challenge to Restasis-related patents.
- The litigation was Civil Action No. 1:16-cv-01114-RGA in the District of Delaware.
- U.S. Patent Nos. 8,629,111 and 9,248,191 were the principal patents at issue.
- The district court held the asserted claims invalid for obviousness.
- The Federal Circuit affirmed in 2019.
- The case weakened Allergan's ability to block generic cyclosporine ophthalmic emulsion products.
- Restasis exclusivity depended on formulation patents because cyclosporine and the general ophthalmic use were known.
- The litigation did not involve biosimilar competition.
- The case was part of a broader Restasis patent and FDA approval strategy involving multiple generic applicants.
- Later patent transfers to the Saint Regis Mohawk Tribe did not prevent the invalidity judgment or related PTAB proceedings.
FAQs About Allergan v. Teva and Restasis Patent Litigation
What ANDA did Teva file for the Restasis litigation?
Teva filed an ANDA for a generic cyclosporine ophthalmic emulsion equivalent to Restasis and submitted Paragraph IV certifications against Allergan's listed patents.
Were the Restasis patents invalidated for lack of written description?
No. The principal holding in the Teva case was invalidity for obviousness under Section 103.
Could Teva launch immediately after the Federal Circuit decision?
Not automatically. Launch depended on FDA approval, the status of other listed patents, any injunction or stay, and the final procedural posture of the case.
Did the Restasis litigation involve patent-term extension?
The commercial dispute focused on Orange Book-listed formulation patents and Hatch-Waxman litigation. The relevant analysis must distinguish ordinary patent expiration from any patent-term adjustment or extension applicable to a particular patent.
Did Allergan's Restasis patent strategy affect other pharmaceutical companies?
Yes. The case influenced generic applicants, branded-drug companies, and patent licensors evaluating formulation patents, Paragraph IV risk, sovereign-immunity transactions, and the enforceability of late-issued pharmaceutical patents.
References
-
Allergan Sales, LLC v. Teva Pharmaceuticals USA, Inc., No. 1:16-cv-01114-RGA, 2017 WL 4803941 (D. Del. Oct. 25, 2017).
-
Allergan Inc. v. Teva Pharmaceuticals USA, Inc., 2019 U.S. App. LEXIS 27180 (Fed. Cir. Sept. 6, 2019).
-
U.S. Food and Drug Administration. (2024). Approved drug products with therapeutic equivalence evaluations. Orange Book.
-
Drug Price Competition and Patent Term Restoration Act of 1984, 21 U.S.C. § 355(j).
-
Saint Regis Mohawk Tribe v. Mylan Pharmaceuticals Inc., 896 F.3d 1322 (Fed. Cir. 2018).
-
U.S. Food and Drug Administration. (2022). FDA approves first generic of Restasis to treat dry eye disease.
-
Allergan plc. (2017). Annual report for fiscal year 2016.
