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United States Patent 10,004,745 (Method Claims) for Follicular Lymphoma After Prior Therapy: What the Claims Cover and How Competitors Can Design Around

US Patent 10,004,745 is a US method-of-treatment patent aimed at delivering a specific once-daily oral dosing regimen (about 560 mg) of a defined chemical entity to treat follicular lymphoma in patients who have failed at least one prior follicular lymphoma therapy. The claim set is broad at the method level, anchored by (i) the disease state (follicular lymphoma post-failure), (ii) the dosing parameters (once per day about 560 mg), and (iii) the administered chemical structure. Dependent claims narrow by histologic subgroup and response endpoint, with a final dependent claim tied to prior rituximab therapy.

This patent landscape analysis below focuses on what the asserted claim elements require, what types of FDA-labeled regimens can map to the claim boundaries, and how other sponsors typically invalidate or design around similar method-of-use claims: changing dose, changing frequency, changing patient selection criteria, changing end-point framing, or using a different active chemical entity.

What is claimed in US Patent 10,004,745 for follicular lymphoma after prior therapy?

Claim 1: Core method-of-use elements (the infringement backbone)

Claim 1 requires all of the following elements:

Indication / patient population
- Treating follicular lymphoma in an individual who has failed at least one prior therapy for follicular lymphoma.
Administration mode
- Administering to the individual an oral dose.
Dose amount
- Once per day and about 560 mg.
Chemical identity
- Administering a compound defined by a chemical structure (provided in the claim specification as a structural drawing).

Legal note for portfolio strategy: Method claims in US practice often hinge on whether the accused infringer’s product labeling, prescribing instructions, clinical use practices, or promotional materials induce or mediate the claimed steps. Even if a clinician could theoretically choose non-infringing steps, infringement risk rises sharply when commercial materials align with the claimed regimen.

Claims 2–7: Dependent limitations that narrow but also define safe harbors

Claim 2 (histology subset): folicular small cleaved, follicular mixed small cleaved/large, or follicular large cell.
Claim 3 (response latitude): stable disease, partial response, or complete response.
Claim 4 (response narrower): partial response or complete response.
Claim 5 (response strictest): complete response.
Claim 6 (progression endpoint): no progressive disease following administration.
Claim 7 (prior therapy anchor): prior therapy included rituximab.

Portfolio implication: Dependent claims do not replace Claim 1. They add additional constraints that can reduce infringement exposure for products that match Claim 1 but do not match a dependent limitation (for example, a product used at a different dose, or in a different failure population, or without histology subset emphasis).

Which elements of claim 1 most constrain infringement risk: the dose, the frequency, the “about 560 mg,” or the oral regimen?

Dose and frequency: the most design-around-friendly levers

Claim 1 is built around once per day and about 560 mg. These are the first places an innovator competitor will look for:

Lower or higher fixed-dose alternatives (for example, shifting to a dosing scheme that is not “about 560 mg”).
Different frequency (twice daily split doses, alternate-day dosing).
Different dosing unit presentation that could argue “about 560 mg” is not met by the prescriber’s practical regimen.

Why “about” matters: “About 560 mg” creates flexibility. Courts often interpret “about” in light of the specification and prosecution history. As a result, design-arounds typically avoid the gray zone by moving outside a reasonable “about” range rather than making minor adjustments.

Oral route: fewer alternatives, but could still be challenged

The claim requires an oral dose. Design-around pathways are narrower here:

Switching to an alternative route is structurally possible only if the active ingredient supports it, which is often not the case for kinase or orally bioavailable small molecules.

Patient selection (“failed at least one prior therapy”)

This is a second major infringement constraint:

If a competitor’s clinical use concentrates on front-line or earlier-line settings (no prior failure), it weakens mapping to Claim 1.
If the comparator product is used post-failure, infringement risk rises.

In practice, many follicular lymphoma regimens are used in relapsed/refractory settings, so this element is often met. Still, marketing and labeling matter: if the competing product’s approved indications are not aligned with “failed at least one prior therapy for follicular lymphoma,” risk shifts.

How do histology and response dependent claims (claims 2–6) change the infringement analysis?

Claim 2 histologic subset

Claim 2 locks to three histologic buckets:

follicular small cleaved cell lymphoma
follicular mixed small cleaved and large cell lymphoma
follicular large cell lymphoma

If the competing product is used in follicular lymphoma populations that include other histologic presentations (or if labeling and clinical trial cohorts broaden beyond those buckets), there is a pathway to contest dependent-claim infringement. Claim 1 still stands, but dependent claims often become important in damages and injunction arguments.

Claims 3–6: response endpoint framing

Claims 3–6 are post-treatment outcome dependent:

stable disease
partial response
complete response
no progressive disease

These claims can be difficult to police unless:

labeling, trial results, or promotional materials emphasize the same endpoints; and
the infringement theory includes method execution after the clinical evaluation timepoints.

In licensing disputes, these types of claims also become sensitive to:

definitions of response and progression (RECIST-based, follicular lymphoma response criteria, time windows); and
whether the claimed “following administration” is satisfied in the accused use population and practice.

What does claim 7 add by tying prior therapy to rituximab?

Claim 7 adds an anchor: prior therapy included rituximab. In competitive infringement terms:

If a competitor can show its relapsed/refractory patients are pretreated with other regimens but not rituximab, it can weaken dependent claim coverage.
Rituximab is standard-of-care historically in follicular lymphoma. Many real-world populations will have received it. That said, the claim requires “prior therapy comprised administration of rituximab,” which can be contested based on actual patient history and how promotion frames eligible populations.

How strong is the claim set as a patent estate for blocking generics or competing branded drugs?

Strengths

Tight regimen anchors: oral route, once-daily dosing, and a specific approximate dose.
Clear clinical population: follicular lymphoma after failure of at least one prior follicular lymphoma therapy.
Chemical identity anchor: structural claim element prevents simple substitution with another active (design-around must change the chemical entity).

Weaknesses typical of this structure

Even where Claim 1 is strong on paper, method claims face common challenges:

Indefiniteness / claim construction around “about 560 mg”
- The scope of “about” can be litigated. If the specification does not calibrate the range tightly, defenders push for narrower constructions or argue non-equivalency.
Medical practice variance
- If the accused product dosing in practice or in labeling is not once per day and/or does not hit an amount that fits “about 560 mg,” infringement risk decreases.
Prior therapy failure criterion
- If indications differ across geographies or if the product is used in earlier lines or in clinical studies that exclude relapsed/refractory failures, mapping is reduced.
Response/outcome dependence (claims 3–6)
- Outcome-based dependent claims can be harder to enforce without direct evidence tying treated patients to the endpoint claims.

What competitor design-around options are most realistic for a method-of-treatment claim tied to 560 mg once daily oral dosing?

Option 1: Change dose amount outside the “about 560 mg” boundary

The most common approach is a different tablet strength and regimen such that the total daily amount is materially different.

Option 2: Change dosing frequency

A two-times-daily schedule can be an effective route if it is clinically standard for the competing product.

Option 3: Change the eligible patient population via labeling and marketing

If a product’s labeled indication is earlier line (or non-failure), the method claim can be avoided.

Option 4: Use the same mechanism but a different chemical entity

Because Claim 1’s administered compound is defined by structure, a different active ingredient avoids literal structural infringement. The only remaining risk becomes doctrine of equivalents, which is narrower for structural chemical definitions.

What patents likely coexist with US 10,004,745 in the same technology family, and what would that mean for freedom-to-operate?

Without the underlying identity of the compound from the structural drawing, a complete, accurate family mapping cannot be performed. A method-of-use patent like 10,004,745 usually sits alongside some combination of:

composition-of-matter patents (active chemical structures),
formulation patents (tablet/capsule, dissolution profile),
dosing regimen patents (treatment schedules and dose amounts),
method patents tied to specific biomarkers, response criteria, or combination therapies.

Business impact: If 10,004,745 is a method-of-use patent without broad compound coverage, a generic competitor may face fewer barriers for chemical synthesis, but still face risk if it markets a product intended for the same dosing and patient failure population.

Orange Book status and FDA regulatory entry risks: what matters for method-of-use patents?

For US method-of-use patents, FDA listing in the Orange Book can create leverage in Paragraph IV litigation. The infringement question becomes whether the generic’s proposed labeling “carves in” the method-of-use steps:

the same indication language,
the same dose and schedule, and
similar “after prior therapy failure” qualifiers.

If a generic can propose labeling that omits the claimed dosing regimen or changes indication wording, the practical risk often shifts from inevitability to dispute. Conversely, if the generic’s label mirrors the innovator’s method-of-use language, litigation pressure increases.

How does patent expiration timing affect generic entry scenarios for US 10,004,745?

Method-of-use patents typically expire 20 years from the earliest non-provisional priority date (subject to PTA/PTE adjustments). The earliest filing date is not provided in the claim text, so an exact expiration calendar cannot be computed here.

Strategic reality for generic and biosimilar-adjacent cases (for small molecules) is that expiration timing interacts with:

Orange Book listing status,
settlement timing,
patent term adjustments,
and whether the patent is asserted in first-wave Paragraph IV actions.

What would a Paragraph IV challenge to US 10,004,745 likely argue?

Common invalidity and non-infringement routes for method-of-treatment patents like this include:

Non-infringement

The accused regimen does not administer a compound with the same structural features.
The accused regimen does not use oral once-daily dosing or does not deliver about 560 mg daily.
The patient population does not meet “failed at least one prior therapy for follicular lymphoma.”
Clinical endpoints are not the same or not achieved in a way that satisfies dependent claims (3–6).

Invalidity

Obviousness based on prior art showing similar dosing schedules, oral administration, and follicular lymphoma treatment post-relapse.
Lack of enablement or written description if the method and dosing are broader than the evidence supporting it.
Indefiniteness or claim construction disputes around “about 560 mg.”

Claim-chart criticality: where exactly are the infringement trigger points?

Below is a practical claim-element matrix that a litigant typically uses:

Claim element	What must be shown	Most common evidence sources
Follicular lymphoma	Patient diagnosis	Medical records, trial inclusion criteria
Failed ≥1 prior follicular lymphoma therapy	Relapsed/refractory history	Records, prior treatment lines
Oral dose	Route of administration	Labeling, prescribing info, pharmacy records
Once per day	Dosing schedule	Labeling, medication history
About 560 mg	Daily dose amount	Pill strength, regimen instructions, adherence records
Compound structure	Chemical identity	Product identity, ANDA chemistry, reference to structure in patents

Dependent claims then add:

histology subclass (Claim 2),
response categories (Claims 3–6),
rituximab prior therapy (Claim 7).

Key Takeaways

US 10,004,745 is a method-of-treatment patent built on a specific regimen: oral, once-daily dosing at about 560 mg of a structurally defined compound for follicular lymphoma after failure of at least one prior follicular lymphoma therapy.
Claim 1 is the main risk anchor. The most realistic design-arounds target dose amount, frequency, and patient selection/labeling rather than route or disease definition.
Dependent claims (2–7) add narrower histology and outcome constraints, which can reduce enforcement reach but do not eliminate Claim 1 risk when the regimen and patient population match.
Litigation leverage typically turns on Orange Book listing and whether generic labels and real-world prescribing practices align with the claimed regimen and failure-line indication framing.

FAQs

What dosing changes would likely avoid infringement of the “once per day about 560 mg” method?

A regimen that is not once daily and/or that produces a daily administered amount that falls outside a reasonable interpretation of “about 560 mg” reduces literal infringement risk.

Can a generic product avoid infringement by changing indication language from relapsed to first-line follicular lymphoma?

Yes. If labeling and promotional materials do not target the “failed at least one prior therapy” population for follicular lymphoma, method-of-use infringement theories weaken.

Do response-based dependent claims (stable disease, partial response, complete response) matter in enforcement?

They can matter for damages narratives, but they are harder to prove as a matter of routine labeling risk because they depend on clinical outcomes after treatment.

Does prior rituximab history (Claim 7) affect infringement only for that dependent claim?

Yes. Claim 7 adds a prior-therapy composition limitation. It does not remove Claim 1 coverage if the once-daily 560 mg oral regimen for failed follicular lymphoma is otherwise met.

How does product labeling influence whether method-of-use steps are “encouraged” in practice?

Labels and prescribing information that mirror the claimed regimen and eligible patient population make it more likely that the method steps are followed in the market, supporting inducement-style theories.

References

No external sources were cited because the claim set provided does not include the patent’s specification details, earliest priority date, assignee(s), prosecution history, related family members, or FDA/Orange Book listing status.

Applicant	Tradename	Biologic Ingredient	Dosage Form	BLA	Approval Date	Patent No.	Expiredate
Genentech, Inc.	RITUXAN	rituximab	Injection	103705	November 26, 1997	⤷ Start Trial	2036-03-10
Genentech, Inc.	RITUXAN HYCELA	rituximab and hyaluronidase human	Injection	761064	June 22, 2017	⤷ Start Trial	2036-03-10
>Applicant	>Tradename	>Biologic Ingredient	>Dosage Form	>BLA	>Approval Date	>Patent No.	>Expiredate

Patent: 10,004,745

Summary for Patent: 10,004,745