US Patent 9,931,334: Ivacaftor Amorphous-Form Claims, Exclusivity, Litigation Risk, and Patent Landscape
US Patent 9,931,334 protects selected amorphous solid forms of ivacaftor, the active ingredient in Kalydeco, when used to treat cystic fibrosis with another therapeutic agent. Its commercial scope is narrower than the underlying ivacaftor compound patents because it requires a defined physical state of ivacaftor, limits crystalline content, and generally requires combination use.
The patent is commercially relevant to Kalydeco and potentially to products containing ivacaftor, including combination regimens involving CFTR modulators. It is not a patent on all ivacaftor use, all cystic fibrosis treatment, or all ivacaftor formulations.
What drug does US Patent 9,931,334 protect?
The claimed chemical compound is ivacaftor, also known as VX-770 and marketed as Kalydeco. The chemical name in the claims is:
N-[2,4-bis(1,1-dimethylethyl)-5-hydroxyphenyl]-1,4-dihydro-4-oxoquinoline-3-carboxamide.
Ivacaftor is a CFTR potentiator approved by the FDA for treatment of cystic fibrosis in patients with qualifying CFTR mutations. Kalydeco was approved in 2012 under NDA 203188. The patent does not claim the molecular structure of ivacaftor itself. Earlier patents cover the compound and broader therapeutic uses.
What are the independent claims in US 9,931,334?
The patent has four principal independent claim groups.
| Claim |
Claim type |
Core limitation |
| 1 |
Method of treatment |
Administering a solid composition containing amorphous ivacaftor and less than about 30% crystalline ivacaftor, with another therapeutic agent |
| 7 |
Method of treatment |
Administering 100% amorphous ivacaftor, measured by Cu K-alpha X-ray powder diffraction, with another therapeutic agent |
| 9 |
Composition |
Solid composition containing amorphous ivacaftor, less than about 30% crystalline ivacaftor, and another therapeutic agent |
| 16 |
Composition |
Solid composition containing 100% amorphous ivacaftor and another therapeutic agent |
The dependent claims add:
- less than about 5% crystalline ivacaftor;
- a solid dispersion;
- a polymer;
- a pharmaceutically acceptable excipient;
- treatment of cystic fibrosis;
- specified categories of combination agents.
The patent therefore combines three claim concepts:
- Physical form: amorphous ivacaftor.
- Crystallinity threshold: less than approximately 30%, or less than approximately 5%, crystalline material.
- Combination use: another therapeutic agent must be present or administered.
How broad is the scope of the amorphous ivacaftor claims?
The patent’s strongest commercial protection is directed to a solid dosage product containing substantially amorphous ivacaftor together with a qualifying additional agent.
The claims do not require a specific polymer, excipient, manufacturing process, particle size, dose, tablet strength, or named combination product. That gives the composition claims some flexibility. A competing product could fall within the claims even if it uses different excipients or a different manufacturing process, provided the final product contains the claimed amorphous ivacaftor and additional agent.
The claims are limited in several important ways:
- The composition must be solid.
- The ivacaftor must be amorphous, either entirely or predominantly.
- Claims 1 and 9 require less than about 30% crystalline ivacaftor.
- Claims 5 and 14 narrow the threshold to less than about 5%.
- The claimed method must involve cystic fibrosis treatment.
- The product or treatment must include an additional therapeutic agent.
A product containing only crystalline ivacaftor would generally fall outside these claims. A liquid formulation may also avoid the solid-composition claims, although other method claims could require separate analysis. A product containing amorphous ivacaftor as an impurity or transient processing intermediate may raise different infringement questions from a finished dosage form intentionally containing the amorphous form.
What does “100% amorphous” mean under the patent?
Claims 7 and 16 define 100% amorphous ivacaftor by Cu K-alpha radiation X-ray powder diffraction. The claims therefore use an analytical method rather than an absolute molecular-state standard.
In practical enforcement, the central questions would include:
- Which XRPD peaks distinguish crystalline ivacaftor from the amorphous material?
- What detection limit applies?
- Does “100% amorphous” mean no detectable crystalline peaks or absolute absence of crystallinity?
- Must the test be performed on the finished product or isolated ivacaftor?
- How should crystallinity be measured when excipients, polymers, or other active ingredients interfere with the diffraction pattern?
- Does storage-induced recrystallization remove the product from the claim?
The “100% amorphous” language creates a potential claim-construction and proof issue. Absolute absence of crystallinity is difficult to establish analytically. A generic or follow-on manufacturer could challenge whether the claim is indefinite, not enabled across its full scope, or limited by the patent’s XRPD disclosure.
What formulations are protected by US 9,931,334?
The claims expressly cover solid dispersions and compositions containing polymers, although the independent composition claims are not limited to a particular polymer or dispersion technology.
Potentially covered formats include:
- amorphous ivacaftor-polymer solid dispersions;
- tablets containing amorphous ivacaftor and a CFTR modulator;
- capsules containing amorphous ivacaftor and an antibiotic;
- granules containing amorphous ivacaftor and excipients;
- co-formulated solid products containing ivacaftor and another active ingredient;
- solid dosage forms with less than 5% crystalline ivacaftor.
The claims do not require that the additional agent be physically co-formulated with ivacaftor in every method scenario. Claim 1 requires administering a composition in combination with another therapeutic agent. That wording may cover co-administration of separate products, depending on claim construction and the facts of the accused regimen. Claims 9 and 16 are narrower product claims because the composition itself must comprise the additional therapeutic agent.
Which combination agents fall within the claims?
Claim 2 and related claims identify broad therapeutic categories:
| Category |
Examples potentially relevant to cystic fibrosis |
| Mucolytics |
Dornase alfa, hypertonic saline |
| Bronchodilators |
Albuterol and other inhaled bronchodilators |
| Antibiotics |
Tobramycin, aztreonam, ciprofloxacin |
| Anti-infectives |
Agents used against chronic pulmonary infection |
| Anti-inflammatory agents |
Selected anti-inflammatory therapies |
| CFTR modulators |
Tezacaftor, elexacaftor, lumacaftor |
| Nutritional agents |
Products supporting cystic fibrosis nutritional management |
The category language is broad, but the claims still require the claimed amorphous ivacaftor formulation. A regimen using Kalydeco with another therapy may implicate the method claims only if the ivacaftor product satisfies the amorphous and crystallinity limitations.
The patent does not automatically cover every use of Trikafta, Symdeko, or Orkambi. Those products contain different combinations and, in some cases, ivacaftor. Coverage depends on the physical form of ivacaftor in the relevant product and the precise claim language applicable to the product or regimen.
When does US Patent 9,931,334 lose exclusivity?
The patent was granted on April 3, 2018. Its term is governed by the earliest applicable nonprovisional or international filing date, subject to patent-term adjustment, terminal disclaimers, and any patent-term extension reflected in official records.
Public patent records associate the patent with an ivacaftor amorphous-form patent family originating from the 2011 filing period. The base term is therefore expected to fall around 2031, before accounting for any patent-term adjustment. The exact expiration date should be taken from the USPTO patent record and the FDA Orange Book listing applicable to the approved product.
The patent is separate from regulatory exclusivity. FDA new-drug exclusivity for Kalydeco does not extend for the life of the patent. Any generic applicant may use the ANDA pathway after applicable regulatory barriers expire, but a listed patent can delay approval or create litigation exposure.
Exclusivity timeline
| Event |
Date |
| Kalydeco FDA approval |
January 31, 2012 |
| US Patent 9,931,334 grant |
April 3, 2018 |
| Expected base patent-term period |
Approximately 2031, subject to official term calculation |
| Regulatory pathway for generic ivacaftor |
ANDA under Section 505(j), not biosimilar pathway |
What is the Orange Book status of US Patent 9,931,334?
US Patent 9,931,334 has been associated with the Kalydeco patent estate and is relevant to FDA-listed patent analysis for ivacaftor products. Orange Book listing status must be evaluated by product, NDA, dosage form, and current FDA publication.
A listed patent can create a Paragraph IV certification issue for an ANDA applicant. The applicant may certify that the patent is invalid, unenforceable, or will not be infringed. The NDA holder may then bring a patent infringement action under the Hatch-Waxman framework.
The key regulatory distinction is:
- Orange Book patents may delay approval of an ANDA through statutory litigation stays.
- Patent claims not properly listed for the relevant NDA may remain enforceable in district court but may not create the same ANDA approval barrier.
- The patent’s composition and method claims must be mapped to the approved Kalydeco product and labeling.
Which companies are challenging Kalydeco patents?
The relevant generic challengers are companies pursuing abbreviated applications for ivacaftor or related CFTR-modulator products. Public records should be checked for current Paragraph IV certifications, ANDA litigation complaints, and FDA patent-listing updates.
The supplied claim set alone does not establish that a particular company has filed a Paragraph IV certification against US Patent 9,931,334. No specific challenger, litigation docket, or settlement agreement can be attributed to this patent solely from the claim text.
A Paragraph IV challenge would likely focus on:
- whether the proposed product contains amorphous ivacaftor;
- whether crystalline content is below the claimed threshold;
- whether the proposed use includes cystic fibrosis treatment;
- whether the additional agent limitation is met;
- whether the asserted claims are obvious in view of known amorphous solid dispersions;
- whether “100% amorphous” is definite and analytically reproducible.
How strong is the patent estate for amorphous ivacaftor?
The patent has meaningful protection against an exact copy of the claimed amorphous formulation, but its strength is narrower than the core compound estate.
Strengths
- The claims cover both treatment methods and compositions.
- The composition claims do not require a single named polymer.
- The claims cover a crystallinity range below approximately 30%.
- The dependent claims provide a narrower less-than-5% crystalline fallback.
- The claims address a commercially relevant cystic fibrosis treatment setting.
- Solid-state form claims can be difficult to design around if the approved product depends on improved dissolution or bioavailability.
Vulnerabilities
- Amorphous forms and solid dispersions are established pharmaceutical technologies.
- The additional-agent limitation narrows infringement.
- The “100% amorphous” limitation may raise indefiniteness and proof questions.
- XRPD detection limits may produce disputes over the meaning of the claim.
- A manufacturer may develop a crystalline form, a different polymorph, a liquid formulation, or a separate-product regimen.
- Obviousness may be argued based on known methods for improving dissolution of poorly soluble compounds.
Overall, the estate is strongest against a product that reproduces the same amorphous ivacaftor solid dispersion and markets it for use with a qualifying cystic fibrosis therapy. It is weaker against products using a different solid state or avoiding the combination limitation.
What generic launch scenarios exist for ivacaftor?
| Launch scenario |
Patent risk under US 9,931,334 |
| Generic reproduces amorphous ivacaftor solid dispersion |
High |
| Generic uses less than 5% crystalline ivacaftor |
High if other limitations are met |
| Generic uses a predominantly crystalline formulation |
Lower under these claims |
| Generic sells ivacaftor alone without a combination product |
Lower for composition claims; method claims require separate analysis |
| Generic uses a liquid or non-solid formulation |
Potentially lower for composition claims |
| Generic labels only for non-patented uses |
Depends on the approved label and induced-infringement analysis |
| Generic uses a different polymer but retains amorphous ivacaftor |
Potentially high |
| Generic uses separate ivacaftor and companion products |
Depends on whether the method claims cover the combined administration |
A manufacturer seeking to avoid the patent would likely prioritize a demonstrably crystalline formulation or a product whose labeling does not encourage the claimed combination use. That strategy must be assessed against other ivacaftor patents and FDA requirements.
How does this patent compare with the broader ivacaftor patent estate?
The ivacaftor estate can be divided into four layers:
| Patent layer |
Typical subject matter |
Relative scope |
| Core compound patents |
Ivacaftor chemical structure and related quinoline compounds |
Broadest |
| Therapeutic-use patents |
Treatment of cystic fibrosis and CFTR-related disorders |
Broad method protection |
| Solid-state patents |
Amorphous ivacaftor, polymorphs, crystallinity, solid dispersions |
Narrower but product-focused |
| Combination and formulation patents |
Ivacaftor with other CFTR modulators, excipients, or dosage technologies |
Product- and regimen-specific |
US Patent 9,931,334 is a solid-state and combination patent. It does not replace the earlier compound and therapeutic-use patents. A generic launch may need to clear several patent families, not only this patent.
The patent is also relevant to products containing ivacaftor as part of a combination regimen, but protection for Trikafta, Symdeko, and Orkambi is determined separately through their own product patents, labeling, formulation claims, and Orange Book listings.
What licensing deals affect the ivacaftor patent landscape?
Ivacaftor originated from Vertex’s CFTR-modulator research, including historical collaboration and acquisition activity involving Aurora Biosciences. Vertex also has a long-standing relationship with the Cystic Fibrosis Foundation relating to CF drug development and commercialization economics.
Those relationships do not establish that a third party owns or licenses the specific claims of US Patent 9,931,334. The patent should be treated as part of the Vertex-controlled ivacaftor intellectual-property portfolio unless an assignment, exclusive license, or settlement agreement states otherwise.
What litigation and settlement issues should companies monitor?
The main litigation risks are:
- Hatch-Waxman litigation following a Paragraph IV certification.
- Claim-construction disputes over “100% amorphous.”
- Expert disputes over XRPD methodology and detection limits.
- Obviousness challenges based on solid-dispersion literature.
- Induced-infringement claims based on cystic fibrosis labeling.
- Product-by-process and manufacturing evidence concerning recrystallization.
- Settlement agreements that restrict generic launch dates or licensing rights.
A settlement can materially alter the practical expiration date even when the statutory patent term remains unchanged. A public patent number alone does not establish whether a settlement exists or whether a generic has a licensed entry date.
Is there biosimilar risk for ivacaftor?
No. Ivacaftor is a chemically synthesized small molecule, not a biologic. Competitors would generally pursue an ANDA under Section 505(j), not a biosimilar application under Section 351(k) of the Public Health Service Act.
The relevant competitive risks are generic ivacaftor, authorized generic entry, formulation workarounds, and combination-product competition. Biosimilar interchangeability standards do not apply.
Key Takeaways
- US Patent 9,931,334 covers amorphous ivacaftor solid compositions and cystic fibrosis treatment using those compositions with another therapeutic agent.
- The principal thresholds are less than approximately 30% crystalline ivacaftor and, in narrower claims, less than approximately 5%.
- Claims 7 and 16 require 100% amorphous ivacaftor as measured by Cu K-alpha XRPD.
- The patent does not claim all ivacaftor products or all cystic fibrosis uses.
- A crystalline formulation, non-solid formulation, or regimen avoiding the additional-agent limitation may provide a design-around path.
- The patent was granted April 3, 2018, with an expected base term around 2031, subject to the official USPTO term calculation.
- Generic applicants face ANDA and Paragraph IV risks rather than biosimilar litigation.
- The strongest infringement case would involve an amorphous ivacaftor solid dispersion substantially matching the claimed composition and labeled for combination cystic fibrosis treatment.
- Commercial clearance requires review of the entire Vertex ivacaftor estate, including compound, use, formulation, combination, and Orange Book-listed patents.
FAQs
Does US Patent 9,931,334 cover Kalydeco tablets?
It may be relevant to Kalydeco if the marketed product contains the claimed amorphous form and satisfies the combination-use or composition limitations. Product-specific coverage depends on the applicable FDA listing and the formulation’s verified solid-state characteristics.
Can a generic avoid the patent by using a different polymer?
Not necessarily. The independent claims do not require a particular polymer. A different polymer may still infringe if the product contains amorphous ivacaftor, satisfies the crystalline-content limitation, and includes the required additional therapeutic agent.
Does the patent cover ivacaftor monotherapy?
The claims supplied require an additional therapeutic agent. Ivacaftor monotherapy therefore presents a stronger non-infringement position under these claims, although other ivacaftor method and compound patents may apply.
What test determines whether a product is 100% amorphous?
The claims identify Cu K-alpha radiation X-ray powder diffraction. The litigation issue would be whether the product has no detectable crystalline peaks under the validated test conditions and detection limits used to interpret the patent.
Is US Patent 9,931,334 relevant to Trikafta?
It can be relevant only if the ivacaftor component in the relevant product or regimen satisfies the claimed amorphous-form and combination limitations. Trikafta has its own patent and regulatory estate, which must be analyzed separately.
References
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U.S. Patent No. 9,931,334. (2018). Amorphous forms of ivacaftor and methods of use thereof. United States Patent and Trademark Office.
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U.S. Food and Drug Administration. (2012). Kalydeco (ivacaftor) prescribing information. FDA.
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U.S. Food and Drug Administration. (n.d.). Approved drug products with therapeutic equivalence evaluations. FDA, Orange Book.
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U.S. Patent and Trademark Office. (n.d.). Patent term adjustment and patent term calculation records. USPTO.
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Vertex Pharmaceuticals Incorporated. (2024). Annual report pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934. U.S. Securities and Exchange Commission.
