Last updated: August 12, 2026
Ferring Pharmaceuticals Inc. v. Par Pharmaceutical Inc., No. 1:15-cv-00173, was a Hatch-Waxman patent case in the U.S. District Court for the District of Delaware concerning Par's ANDA for a generic version of Ferring's PREPOPIK bowel-preparation product. Ferring asserted patents covering the sodium picosulfate, magnesium oxide, and anhydrous citric acid formulation and its use for colon cleansing. The case was resolved by settlement and stipulated dismissal rather than a publicly reported merits judgment. The settlement terms and any authorized generic-entry date were not publicly disclosed in the docket materials.[1]
What drug and patents were at issue in Ferring v. Par?
The litigation involved PREPOPIK, an oral solution powder for bowel cleansing before colonoscopy. The product contains three active ingredients:
- Sodium picosulfate
- Magnesium oxide
- Anhydrous citric acid
Ferring marketed PREPOPIK under NDA No. 022372. The FDA approved the product on July 16, 2012.[2]
Ferring's complaint followed Par's filing of an Abbreviated New Drug Application seeking approval to market a generic equivalent. The ANDA filing triggered the statutory 30-month stay under Hatch-Waxman, subject to the course of the litigation and any earlier court order or settlement.[1]
Asserted patent estate
The case principally involved the following U.S. patents:
| Patent |
General subject matter |
Listed expiration commonly reported for PREPOPIK |
| U.S. Patent No. 8,337,886 |
Bowel-cleansing compositions and related formulation technology |
June 11, 2027 |
| U.S. Patent No. 8,545,468 |
Bowel-cleansing compositions and administration technology |
June 11, 2027 |
The patents addressed the combination of active ingredients and the formulation's use in bowel preparation. Their commercial relevance depended on whether the claims covered Par's proposed product and labeling, not merely whether Par's product contained the same active ingredients.[1][3]
What were Ferring's infringement claims against Par?
Ferring alleged that Par's ANDA product would infringe the asserted patents under 35 U.S.C. § 271(e)(2), which treats the filing of an ANDA with a Paragraph IV certification as an artificial act of patent infringement.
The infringement theory likely turned on two related claim categories:
- Composition claims covering the combination of sodium picosulfate, magnesium oxide, and citric acid in specified amounts, ratios, or physical arrangements.
- Method-of-use claims covering administration of the bowel-preparation product before colonoscopy, including dosing sequence and timing.
Because PREPOPIK is a combination product, the patent analysis was not limited to the presence of each ingredient. Claim scope could turn on:
- Ingredient concentration
- Relative amounts of magnesium oxide and citric acid
- Whether the ingredients were separated or combined in particular sachets
- Reconstitution instructions
- The volume of water used
- The timing of the two doses
- The proposed generic labeling
The ANDA label is central in method-of-use litigation. If the proposed label directs the patented bowel-cleansing method, a plaintiff may establish infringement even where the generic manufacturer does not independently practice the method.
What defenses did Par have in the PREPOPIK patent case?
Par's principal defenses in a Hatch-Waxman case of this type would have included noninfringement and invalidity.
Noninfringement
Par could argue that its proposed product or label did not satisfy one or more claim limitations. For composition claims, the arguments could concern formulation ratios, ingredient placement, dosage strength, or physical form. For method claims, Par could challenge whether the proposed directions required every step of the claimed administration method.
A label-based noninfringement defense is difficult when the generic label closely follows the reference drug's FDA-approved labeling. It becomes more viable where the generic applicant can omit a patented indication or instruction through a section viii statement, provided the omitted use is legally separable from the remaining approved uses.
Invalidity
Par also had grounds to challenge validity under:
- 35 U.S.C. § 102, anticipation
- 35 U.S.C. § 103, obviousness
- 35 U.S.C. § 112, written description and enablement
Bowel-preparation formulations commonly face obviousness challenges based on prior art disclosing the individual ingredients, related electrolyte formulations, and known colonoscopy-preparation regimens. The decisive issue is usually whether the claimed combination, concentration profile, administration schedule, or formulation architecture produced an unexpected technical result.
The asserted patents' commercial value therefore depended on claim limitations that distinguished PREPOPIK from earlier sodium picosulfate bowel preparations and from conventional magnesium- and citrate-based products.
What was the litigation timeline in Ferring v. Par?
| Date |
Event |
| July 16, 2012 |
FDA approved PREPOPIK under NDA No. 022372.[2] |
| February 25, 2015 |
Ferring filed the patent-infringement action in the District of Delaware.[1] |
| 2015 |
The case proceeded under Hatch-Waxman procedures following Par's ANDA filing and Paragraph IV position. |
| 2015-2016 |
The parties litigated claim scope, infringement, validity, and discovery issues. |
| 2016-2017 |
The case was resolved through settlement. |
| Final disposition |
The docket reflects stipulated dismissal rather than a public trial judgment establishing patent validity or infringement.[1] |
The public docket does not establish that Ferring obtained a litigated finding that the patents were valid and infringed. It also does not establish that Par's ANDA was adjudicated invalid or noninfringing.
When did PREPOPIK lose exclusivity?
PREPOPIK's regulatory exclusivity and patent exclusivity were separate.
The FDA's three-year new-drug exclusivity period associated with the 2012 approval would have ended in 2015, subject to the scope of the exclusivity granted for the approved product and any protected changes.[2] The principal patent protection cited for PREPOPIK extended materially longer, with the key patents commonly reported to expire in 2027.[3]
| Protection type |
Approximate end point |
Business effect |
| FDA three-year exclusivity |
July 2015 |
Removed the regulatory bar to certain ANDA approvals |
| U.S. Patent No. 8,337,886 |
June 11, 2027 |
Continued patent-based entry risk |
| U.S. Patent No. 8,545,468 |
June 11, 2027 |
Continued patent-based entry risk |
| Pediatric exclusivity |
No separate period identified in the cited public record |
No added six-month period should be assumed |
Patent-term calculations can be affected by patent-term adjustment, terminal disclaimers, patent-term extension, and Orange Book corrections. The effective generic-entry date under a settlement can also precede the nominal patent expiration.
What was the Orange Book status of PREPOPIK?
PREPOPIK was an FDA-listed small-molecule prescription drug, not a biologic. Its generic pathway was therefore an ANDA pathway, not a biosimilar application under the Public Health Service Act.
The relevant Orange Book issues were:
- NDA No. 022372
- Patent listings for formulation and use claims
- Par's Paragraph IV certification
- The statutory 30-month stay
- Any settlement-based approval or launch restriction
The Orange Book listing did not itself determine whether the patents were valid or infringed. It supplied the regulatory patent notice mechanism that allowed Ferring to bring the § 271(e)(2) action.[2][3]
Did Ferring and Par enter a patent settlement?
Yes. The case ended through settlement and stipulated dismissal. The publicly available docket does not disclose the core commercial provisions, including:
- Whether Par received a license
- The permitted launch date
- Whether Par received an authorized-generic arrangement
- Any royalty or supply obligations
- Whether the agreement included a no-challenge provision
- Whether the settlement covered other Ferring bowel-preparation patents
The absence of a merits opinion limits the ability to assign a litigation-based probability of invalidity or infringement. A settlement is not evidence that either side accepted the opposing party's patent position.
The Federal Trade Commission's pharmaceutical-settlement review framework would have been relevant to any agreement containing compensation, delayed entry, supply rights, or other restrictions on generic commercialization.[4]
What generic entry risks did the case create?
The case created three distinct entry scenarios.
1. Early licensed entry
Par could launch before the reported 2027 patent expirations if the settlement granted an express license. This is the most commercially important possibility, but the public docket does not disclose the settlement date or license scope.
2. Entry after patent expiration
If Par received no early-entry license, commercial launch would remain constrained by the listed patents until expiration or successful resolution of a later challenge.
3. Entry following patent invalidation or noninfringement
A successful merits decision could have removed the relevant barrier earlier. That outcome did not occur in the public record because the case was dismissed without a reported trial judgment.
Par's generic product also would have faced non-patent barriers, including FDA approval, manufacturing readiness, distribution, reimbursement, and the ability to compete in the bowel-preparation market against other prescription and over-the-counter products.
How strong was Ferring's PREPOPIK patent estate?
Ferring's estate had meaningful commercial coverage because it combined formulation claims with potential method-of-use protection. That structure can create multiple infringement theories against an ANDA applicant.
Its principal strengths were:
- Coverage directed to the distinctive three-ingredient formulation
- Long remaining patent life when the case was filed
- FDA-listed patents supporting a Hatch-Waxman action
- Potential label-based method claims
- A product with a defined pre-colonoscopy use and dosing protocol
Its principal weaknesses were:
- The ingredients were individually known in bowel-preparation products
- Obviousness risk increased if prior art disclosed similar combinations or dosing schedules
- Method claims depended heavily on the generic label
- Settlement prevented a public judicial ruling confirming claim validity
- Patent strength could vary substantially by claim and by the exact ANDA formulation
The estate was stronger as a coordinated product-and-use portfolio than as an assumption of automatic exclusivity through 2027.
Which companies challenged or could challenge PREPOPIK patents?
Par was the defendant in this action. Other generic companies could pursue separate ANDA challenges or rely on different noninfringement positions. A party's ability to enter would depend on its own formulation, certification, labeling, and any settlement with Ferring.
Because PREPOPIK is a small molecule, biosimilar competition was not relevant. Competitive pressure would come from ANDA applicants, other bowel-preparation products, and alternative colonoscopy-preparation regimens.
What was the revenue exposure from the litigation?
The docket does not provide product sales, forecasted generic erosion, settlement payments, or Par's launch economics. Revenue exposure therefore must be assessed through market structure rather than a disclosed case valuation.
The main drivers were:
- Ferring's U.S. PREPOPIK sales before generic entry
- The number and timing of approved ANDA competitors
- Whether Par had first-filer or other market-position advantages
- The extent of substitution by pharmacies and payers
- Competition from other oral bowel-preparation products
- Whether Ferring retained a branded or authorized-generic strategy
An early Par launch would have created material price and share pressure. A launch close to patent expiry would have reduced the settlement's economic value to Par and preserved more of Ferring's branded exclusivity.
Key Takeaways
- Ferring sued Par in Delaware over Par's ANDA for generic PREPOPIK.
- The product is sodium picosulfate, magnesium oxide, and anhydrous citric acid.
- The principal patents were U.S. Patent Nos. 8,337,886 and 8,545,468.
- The commonly reported patent expiration date was June 11, 2027.
- The case ended by settlement and stipulated dismissal, not by a public merits judgment.
- Settlement terms, including any authorized entry date, were not publicly disclosed in the cited docket materials.
- PREPOPIK followed the ANDA pathway; biosimilar risk was not applicable.
- The patent estate had formulation and possible method-of-use value, but its litigated strength was never established through a final opinion in this case.
FAQs About Ferring v. Par and PREPOPIK Patent Litigation
Was Par allowed to launch generic PREPOPIK before 2027?
The public case record does not disclose the settlement's commercial terms or any authorized launch date. An early launch may have been possible only under a license or other settlement right.
Did the court hold that Ferring's PREPOPIK patents were valid?
No public merits judgment in the cited action established validity. The case ended through settlement and dismissal.
Was PREPOPIK protected by a biologic patent or biosimilar exclusivity?
No. PREPOPIK is a conventional small-molecule drug subject to the ANDA framework.
Can a generic omit a patented bowel-preparation use from its label?
Potentially. A section viii carve-out may avoid infringement for a separable patented use, but the feasibility depends on the patent claims, FDA labeling, and whether the remaining label still directs the patented method.
What is the main commercial risk from the Ferring-Par settlement?
The principal risk is an undisclosed early-entry license that could permit Par to launch before the reported 2027 patent expirations, accelerating generic price competition and reducing PREPOPIK revenue.
References
-
U.S. District Court for the District of Delaware. (2015-2017). Ferring Pharmaceuticals Inc. v. Par Pharmaceutical, Inc., No. 1:15-cv-00173. Court docket and filings.
-
U.S. Food and Drug Administration. (2012). FDA approves Prepopik for colonoscopy preparation. FDA drug approval materials.
-
U.S. Food and Drug Administration. (n.d.). Approved drug products with therapeutic equivalence evaluations: Orange Book. FDA.
-
Federal Trade Commission. (2013). Agreement containing consent orders in pharmaceutical patent settlements. Federal Trade Commission.
