US Patent 9,216,982: Scope, Claims, Expiration, and Patent Landscape for Duvelisib
US Patent No. 9,216,982 is a treatment-method patent directed to administering a defined small-molecule compound, or a pharmaceutically acceptable salt, to treat leukemia and lymphoma. The claim set is broad at the disease-class level but narrower than a composition-of-matter patent because infringement requires use of the claimed compound for a covered cancer indication.
The patent is associated with duvelisib, also known as IPI-145, a PI3K-delta and PI3K-gamma inhibitor marketed in the United States as Copiktra. The principal commercial relevance is the potential use of the patent against generic or competing products labeled for chronic lymphocytic leukemia, small lymphocytic lymphoma, follicular lymphoma, diffuse large B-cell lymphoma, or related hematologic malignancies.
What does US Patent 9,216,982 cover?
US 9,216,982 covers methods of treating cancer by administering the claimed compound or a pharmaceutically acceptable salt. Independent claim 1 is the central claim:
- The compound must conform to the claimed chemical formula.
- The compound must be administered in an effective amount.
- The patient must have leukemia or lymphoma.
Claim 2 narrows the patent to the specifically identified compound. Based on the patent family and the commercial development history, that compound is duvelisib, subject to confirmation against the complete chemical structure in the issued patent.
The patent does not claim:
- The compound as a chemical composition in the abstract.
- Every PI3K inhibitor.
- Every treatment of solid tumors.
- Every use of duvelisib regardless of disease.
- A formulation independent of the treatment method.
- A manufacturing process for duvelisib.
The patent instead protects selected therapeutic uses of the compound.
Core claim structure
| Claim group |
Subject matter |
Commercial significance |
| Claims 1-2 |
Treatment of leukemia or lymphoma with the claimed compound or specific compound |
Main method-of-treatment protection |
| Claims 3-18 |
Specific leukemia subtypes |
Expands coverage across hematologic malignancies |
| Claims 24-27 |
Specific lymphoma subtypes |
Relevant to lymphoma labeling and clinical use |
| Claims 19-23 |
Combination treatment with chemotherapy, cytotoxic agents, radiation, or listed agents |
Protects combination-use scenarios |
| Claim 28 |
Combination with fludarabine, cyclophosphamide, rituximab, or combinations |
Relevant to chemoimmunotherapy regimens |
How broad are the leukemia claims?
Claims 3 through 18 create a disease-specific ladder descending from claim 1. They cover:
- B-cell acute lymphoblastic leukemia
- Acute lymphocytic leukemia
- Hairy cell leukemia
- Myelodysplasia
- Myeloproliferative disorders
- Acute myelogenous leukemia
- Chronic lymphocytic leukemia
- Multiple myeloma
- Myelodysplastic syndrome
- Chronic myelogenous leukemia
- Mast cell leukemia
- T-cell acute lymphoblastic leukemia
The broadest leukemia-dependent claim is claim 3, which simply requires that the cancer be leukemia. Claims 4 through 18 identify particular subtypes and disease categories.
From an enforcement perspective, the dependent claims provide fallback positions. If a court construes the general leukemia language narrowly, a patent holder can rely on a more specific disease claim, such as chronic lymphocytic leukemia or acute myelogenous leukemia.
The inclusion of multiple myeloma, myelodysplastic syndrome, myeloproliferative disorders, and mast cell leukemia makes the claim set materially broader than the current commercial label for duvelisib. Those claims may have limited immediate revenue relevance but remain relevant to off-label use, clinical trials, and future label expansion.
Which lymphoma indications are protected?
Claims 6 and 24 through 27 cover lymphoma generally and selected lymphoma subtypes. The express categories include:
- Non-Hodgkin lymphoma
- Hodgkin disease
- Diffuse large B-cell lymphoma
- Small non-cleaved cell lymphoma
- Adult T-cell lymphoma
- B-cell immunoblastic lymphoma
Claim 8 specifically covers diffuse large B-cell lymphoma, or DLBCL. Claims 25 through 27 add further lymphoma-specific limitations.
The method claims can apply to an approved indication, an investigational use, or an off-label use if the other claim elements are satisfied. A generic applicant could therefore face risk from a label that expressly includes a protected lymphoma indication, even if the generic product is not marketed for every disease listed in the patent.
What combination therapies are protected?
Claim 19 covers treatment with the patented compound plus one or more second therapeutic agents selected from:
- Chemotherapeutic agents
- Cytotoxic agents
- Radiation
Claims 20 and 21 narrow the combination to an anti-CD20 antibody and specifically to rituximab. Claim 22 covers chlorambucil. Claim 23 lists a broad group of alkylating and cytotoxic agents, including fludarabine and cyclophosphamide. Claim 28 covers fludarabine, cyclophosphamide, rituximab, or combinations of those agents.
The combination claims create two principal risks.
First, a product label that recommends duvelisib with rituximab or chemotherapy could directly practice the claims. Second, a generic company could face induced-infringement allegations if its labeling encourages physicians to administer the generic product in a claimed combination.
The combination claims are narrower than claim 1 because they require an additional agent or radiation. They may nevertheless be commercially important because hematologic malignancies are frequently treated using multi-agent regimens.
What is the Orange Book status of US 9,216,982?
US 9,216,982 is part of the US patent estate associated with Copiktra and duvelisib. The relevant Orange Book analysis must distinguish between patent listing and practical enforcement.
A listed patent generally identifies one or more approved uses, dosage forms, or other aspects of an approved drug product. A method-of-use patent may be listed with a use code tied to a particular indication. The patent does not automatically block every generic version of the active ingredient if the generic applicant validly uses a section viii statement to carve out the protected indication.
For duvelisib, the principal Orange Book and patent-estate categories are:
| Protection category |
Representative patent role |
Generic significance |
| Composition of matter |
Protects duvelisib itself |
Highest barrier if unexpired |
| Therapeutic method |
US 9,216,982 |
Label and indication dependent |
| Formulation or dosage form |
Later-listed patents may apply |
Depends on generic formulation |
| Manufacturing or solid-state form |
Process or product-by-process limitations |
More difficult to assert against ordinary sales |
| Regulatory exclusivity |
Orphan or other FDA exclusivity |
Separate from patent term |
The precise use code and current listing status should be evaluated against the most recent FDA Orange Book edition. The presence of a patent listing does not establish validity or enforceability.
When does US 9,216,982 lose exclusivity?
The patent issued on December 22, 2015. Its nominal expiration date depends on the effective nonprovisional filing date, patent-term adjustment, terminal disclaimers, and any applicable patent-term extension.
The expected term for the method patent is in the late 2020s. Public patent records and commercial patent summaries generally place the expiration of US 9,216,982 around 2029, subject to the USPTO term calculation and any patent-term adjustment. A reliable diligence conclusion should use the USPTO Patent Examination Data System or Patent Center term calculation rather than an expiration estimate derived only from the issue date. [1]
The patent’s expiration is separate from FDA regulatory exclusivity:
- Patent expiration controls patent-based entry.
- Orphan-drug exclusivity can block approval of the same drug for the same disease or indication even after a patent expires.
- New clinical indications may receive separate regulatory exclusivity.
- Pediatric exclusivity, if granted, can add six months to qualifying patent and exclusivity periods.
For Copiktra, the FDA approved duvelisib for relapsed or refractory CLL/SLL after at least two prior systemic therapies in September 2018 and for relapsed or refractory follicular lymphoma after at least two prior systemic therapies in September 2021. [2] The regulatory exclusivity analysis must therefore be performed indication by indication.
What Paragraph IV challenges affect duvelisib?
A generic applicant seeking approval before patent expiry must address listed patents in an ANDA certification. The principal options are:
- Paragraph III certification, accepting delayed approval until patent expiry.
- Paragraph IV certification, asserting that a listed patent is invalid, unenforceable, or not infringed.
- Section viii statement, carving out a patented method of use from the proposed label.
For US 9,216,982, the section viii route may be commercially significant because the patent is directed to specific cancer uses. A generic applicant could attempt to omit protected indications while retaining nonprotected indications. The strategy becomes more difficult if the approved label and prescribing information encourage use in a disease expressly covered by the patent.
A Paragraph IV challenge would likely focus on:
- Whether the asserted claims are anticipated or obvious.
- Whether the specification adequately supports the full disease list.
- Whether the compound in the generic product is the claimed compound or salt.
- Whether the proposed label induces physicians to practice the claimed method.
- Whether the claims are invalid for lack of enablement or written description.
- Whether the patent is enforceable after prosecution-history review.
No conclusion about a particular ANDA challenge, settlement, or district-court judgment should be drawn solely from the issued claims. ANDA litigation must be checked through FDA filings, PACER, and the relevant district-court docket.
Which companies compete with or challenge the duvelisib estate?
Duvelisib competes with other PI3K-pathway inhibitors and with targeted therapies used in CLL, SLL, and lymphoma.
| Drug |
Active ingredient |
Primary mechanism |
Competitive relevance |
| Copiktra |
Duvelisib |
PI3K-delta and PI3K-gamma inhibition |
Product protected by the patent estate analyzed here |
| Zydelig |
Idelalisib |
PI3K-delta inhibition |
Competing oral PI3K inhibitor |
| Aliqopa |
Copanlisib |
PI3K-alpha and PI3K-delta inhibition |
Competes in follicular lymphoma |
| Ukoniq |
Umbralisib |
PI3K-delta and casein kinase 1-epsilon inhibition |
Former competing PI3K product; US authorization was withdrawn |
| Imbruvica |
Ibrutinib |
BTK inhibition |
Major CLL/SLL competitor |
| Calquence |
Acalabrutinib |
BTK inhibition |
Competes in B-cell malignancies |
| Brukinsa |
Zanubrutinib |
BTK inhibition |
Competes in CLL and lymphoma settings |
| Rituxan and biosimilars |
Rituximab |
CD20 antibody |
Combination partner and therapeutic substitute |
The relevant competitive threat is not limited to a direct duvelisib generic. Physicians may switch to BTK inhibitors, BCL-2 inhibitors, anti-CD20 therapy, CAR-T therapy, or other lymphoma treatments without infringing US 9,216,982.
Does the patent create biosimilar risk?
No. Duvelisib is a chemically synthesized small molecule, not a biologic. A biosimilar pathway under the Public Health Service Act is therefore not the relevant entry mechanism.
The likely challenge pathway is an ANDA for a generic drug under the Federal Food, Drug, and Cosmetic Act. The key issues will be:
- Active-ingredient equivalence.
- Bioequivalence.
- Label carve-outs.
- Orange Book patent certifications.
- Paragraph IV litigation.
- Any remaining regulatory exclusivity.
Rituximab, which appears in the combination claims, is a biologic and has its own biosimilar competition. Rituximab biosimilar entry could reduce the commercial value of the combination claims without directly invalidating or expiring US 9,216,982.
How strong is the patent estate?
US 9,216,982 is strongest against a product that meets all of the following conditions:
- Contains duvelisib or the claimed salt.
- Is prescribed for CLL, lymphoma, or another expressly claimed malignancy.
- Uses a label that recommends or encourages the protected use.
- Is marketed before expiration.
- Cannot avoid the claims through a valid label carve-out.
The patent is weaker against:
- A generic label that excludes all patented indications.
- Use for a disease outside the claimed leukemia and lymphoma categories.
- A product that does not contain the claimed compound.
- Physician use that is not encouraged by the generic label.
- Claims limited by a combination agent that the generic label omits.
The composition-of-matter patents in the duvelisib portfolio are generally more important to generic entry than this method patent. A valid, unexpired composition patent can block all ordinary use of the active ingredient. US 9,216,982 has greater importance after composition protection expires or where a generic attempts a partial indication carve-out.
What litigation and settlement issues matter?
The principal litigation questions are likely to concern:
- ANDA certification against listed duvelisib patents.
- Whether the method patent is properly listed for the approved indication.
- Label-induced infringement.
- Validity of the disease-method claims.
- Patent-term calculation.
- Settlement terms governing generic launch.
- Potential authorized-generic arrangements.
- Licensing or asset-transfer agreements involving the Copiktra rights.
The commercial rights to duvelisib have involved Infinity Pharmaceuticals, Verastem, and later commercial counterparties. Patent ownership, enforcement authority, and licensing rights should be traced through the assignment chain at the USPTO, not inferred solely from the product label.
What generic launch scenarios exist?
Scenario 1: No early Paragraph IV challenge
A generic waits for the relevant composition and method patents to expire. Entry occurs after patent and regulatory barriers lapse.
Scenario 2: Section viii carve-out
The generic removes protected leukemia or lymphoma indications from its label. This reduces litigation exposure but can restrict the product’s commercial market.
Scenario 3: Paragraph IV litigation
The generic challenges validity or infringement. The brand may obtain a 30-month stay of approval under applicable ANDA litigation rules, subject to statutory exceptions and the timing of the litigation.
Scenario 4: Settlement or licensed entry
The parties agree to a negotiated launch date, potentially with an authorized generic, royalty, or other commercial restriction. The settlement must be reviewed for antitrust and FTC scrutiny.
Scenario 5: At-risk launch
The generic launches before final resolution of the patent dispute. This creates exposure to damages, injunctive relief, and possible market withdrawal.
Key Takeaways
- US 9,216,982 is a method-of-treatment patent associated with duvelisib and Copiktra.
- The core claims cover treatment of leukemia and lymphoma with the claimed compound or a pharmaceutically acceptable salt.
- Dependent claims cover CLL, AML, ALL, CML, MDS, multiple myeloma, DLBCL, Hodgkin disease, non-Hodgkin lymphoma, and other hematologic malignancies.
- Combination claims cover rituximab, chlorambucil, fludarabine, cyclophosphamide, radiation, and other agents.
- The patent is more label-sensitive than a composition-of-matter patent.
- A generic may pursue a section viii carve-out, Paragraph IV challenge, or delayed entry.
- Duvelisib has no biosimilar pathway because it is a small molecule.
- The expected patent term runs into the late 2020s, subject to the official USPTO term calculation.
- The commercial strength of US 9,216,982 depends on the status of stronger composition, formulation, and regulatory protections in the broader duvelisib estate.
FAQs
Can a generic duvelisib launch for CLL while carving out lymphoma?
Possibly. The feasibility depends on the Orange Book use codes, the approved label, and whether the remaining CLL language still practices an asserted claim of US 9,216,982.
Does claim 21 independently protect rituximab plus duvelisib?
Yes. Claim 21 depends on claim 19 and narrows the second therapeutic agent to rituximab. It requires the underlying duvelisib treatment and the rituximab combination.
Are multiple myeloma and myelodysplastic syndrome approved Copiktra indications?
The claims include those diseases, but patent coverage does not establish FDA approval. The FDA-approved label must be reviewed separately for each indication. [2]
Can off-label prescribing infringe US 9,216,982?
A physician’s use may fall within the literal scope of a method claim if all claim elements are satisfied. Generic-company liability usually turns on whether the product labeling or other conduct induces the claimed use.
Is a pharmaceutically acceptable duvelisib salt covered?
Yes, the supplied claims expressly include pharmaceutically acceptable salts. The scope still depends on whether the salt contains the claimed active compound and satisfies the applicable claim construction.
References
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United States Patent and Trademark Office. (2015). U.S. Patent No. 9,216,982, methods of treating cancer using PI3K inhibitors. U.S. Department of Commerce.
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U.S. Food and Drug Administration. (2021). Copiktra (duvelisib) prescribing information. FDA.
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U.S. Food and Drug Administration. (2024). Approved drug products with therapeutic equivalence evaluations: Orange Book. FDA.
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U.S. Food and Drug Administration. (2024). Drugs@FDA: FDA-approved drugs, Copiktra. FDA.
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U.S. Food and Drug Administration. (2024). Generic drug user fee amendments and abbreviated new drug application patent certifications. FDA.
