United States Patent 9,642,911 (Valganciclovir Oral Liquid): What Is Claimed, What It Covers, and the US Patent Landscape
Executive summary: US Patent 9,642,911 claims a specific oral liquid pharmaceutical dosage form with a defined per‑mL composition centered on valganciclovir HCl. The claim scope is composition-centric (exact amounts) and framed as a liquid oral dosage form rather than a process claim. Competitive freedom-to-operate around the patent turns primarily on whether a generic can match the claimed composition and concentrations, whether carve-outs exist via dependent claims not provided here, and whether other US patents in the valganciclovir liquid space create blocking “secondary” barriers even if 9,642,911 is designed around.
What does US Patent 9,642,911 claim about valganciclovir oral liquid dosage forms?
Claim type and core scope. Claim 1 is directed to:
- A liquid pharmaceutical dosage form for oral administration
- Having a specific composition per mL, consisting of the following components and quantities
Claim 1 composition (per mL):
- Valganciclovir HCl: 55.15 mg (equivalent to 50 mg valganciclovir free base on a dry basis)
- Povidone K30: 2.00 mg
- Fumaric acid: 2.00 mg
- Sodium benzoate: 1.00 mg
- Sodium saccharin: 0.25 mg
- Mannitol: 57.80 mg
- Tutti-frutti flavor: 1.80 mg
- Purified water: 0.91 mL
Structural implication for infringement. If a competitor’s marketed “valganciclovir oral liquid” uses materially different concentrations or substitutes a different buffer, sweetener, bulking agent, flavor system, or polymer, it is the most direct path to potential non-infringement of claim 1. Conversely, copying the formulation quantities is the most direct route to exposure.
Does claim 1 require an exact match of excipient identity and amounts?
Claim 1 is drafted as a “composition comprising” style dosage formulation with explicit component identities and explicit per‑mL quantities. That drafting pattern typically makes scope tight because:
- The claim sets numerical ranges only if present; here, claim 1 presents specific amounts.
- It recites specific excipients (povidone K30, fumaric acid, sodium benzoate, sodium saccharin, mannitol, and “tutti-frutti flavor”) rather than functional descriptors alone.
A design-around usually needs to change at least one of:
- active salt form (valganciclovir HCl vs different salt or form),
- one or more excipient identities, and/or
- one or more per‑mL quantities.
How is the valganciclovir dose defined in US 9,642,911, and what does “equivalent to 50 mg free base” mean for claim scope?
Active-dose anchor. The claim specifies:
- 55.15 mg valganciclovir HCl per mL, and
- “Equivalent to 50 mg of valganciclovir (as free base) on a dry basis.”
Practical reading for formulation comparison. This converts the claimed salt quantity into a free-base equivalence. For infringement analysis, that equivalence matters because a competitor might try to argue that it doesn’t match the “free base” content even if its HCl content differs slightly, or vice versa.
Design-around patterns.
- A generic trying to keep the same free-base exposure (per mL) but change the salt form would still need to avoid matching the valganciclovir HCl element of the claim.
- A generic matching HCl quantity but altering “dry basis” determination would need analytical leverage, but infringement analysis typically begins with the claimed numeric formulation target.
What formulations are covered by US 9,642,911: oral liquids with buffering/tonicity/sweetening like mannitol, sodium benzoate, and sodium saccharin?
Claim 1 is not a generic “valganciclovir liquid” concept. It is a defined excipient system:
- Povidone K30 (2.00 mg/mL): polymer binder/solubilizer role in many liquid systems
- Fumaric acid (2.00 mg/mL): acidic component and pH control component
- Sodium benzoate (1.00 mg/mL): preservative
- Sodium saccharin (0.25 mg/mL): sweetener
- Mannitol (57.80 mg/mL): tonicity and bulking agent
- Tutti-frutti flavor (1.80 mg/mL): flavor component
- Purified water (0.91 mL/mL): vehicle volume (the residual volume after solids)
Scope conclusion. The claim covers a particular formulation “fingerprint” rather than a broad class defined by functional properties.
What is the patent landscape for valganciclovir liquid formulations in the US, and how does 9,642,911 fit?
Important constraint: Only the claim text provided for US 9,642,911 is available in your prompt. A complete landscape requires the patent’s bibliographic details (publication number, filing date, assignee, related continuation family, and whether there are dependent claims or other US patents in the same family). Without those, a complete and accurate US landscape cannot be produced under the operating constraints.
Given only claim 1, the actionable landscape assessment is limited to scope mechanics:
- US 9,642,911 is most likely relevant to companies developing or licensing valganciclovir oral liquid generics or authorized pediatric formulations that match this exact per‑mL composition.
- Even if a competitor designs around by changing excipients, the market may still face other formulation patents (e.g., different concentration strengths, different buffering systems, different preservatives, or different taste masking approaches).
Because additional US patent documents are not provided, no reliable enumeration of specific other patents, expiration dates, Orange Book listings, or litigation is possible.
When does US 9,642,911 lose exclusivity in the US: how to compute expiration and exclusivity blockers?
Important constraint: Expiration and any potential patent term adjustments or extensions depend on:
- priority date,
- filing/issue dates,
- continuation/claim strategy,
- any PTA/PTA caps,
- regulatory exclusivity (if any) interplay.
The prompt does not provide those bibliographic data. Producing “expiration” numbers or timelines would be inaccurate.
What can be said from claim structure alone:
- US 9,642,911 is a utility patent (composition claim) and would expire based on its statutory term from the relevant filing/priority schedule plus any adjustments.
- Any loss of exclusivity for a generic depends on whether the ANDA formulation infringes and whether there are other blocking patents in the same therapeutic and dosage form space.
A timing schedule cannot be stated without the patent’s key dates.
What generic entry risks exist for valganciclovir oral liquid under 9,642,911?
Primary risk: direct claim 1 infringement.
A generic entrant that manufactures an oral liquid matching:
- valganciclovir HCl at 55.15 mg/mL,
- plus the specified excipient set and amounts,
- and uses it as an oral liquid dosage form,
creates the highest infringement exposure.
Secondary risks (structural, not enumerated):
- If the entrant uses the same active concentration but reformulates excipients, claim 1 may be avoided, but other patents could cover alternate excipient systems, methods of preparing the liquid, taste masking, or stability approaches.
- If the entrant targets a pediatric population and proposes a different concentration strength, claim 1 might be avoided, but dependent claims (not provided) could still capture other strengths.
What patents protect methods of using valganciclovir oral liquid, and do they interact with formulation claim 1?
Important constraint: No method-of-use or other related claims/patents are provided in your prompt. Interactions cannot be mapped without:
- the rest of US 9,642,911’s claim set (dependent claims),
- and other US patents in the family or related families.
General claim-interaction principle: A formulation patent typically does not require a particular method of use, while a method-of-use patent would require use steps. In litigation, that distinction affects whether ANDA-driven infringement theories rely on the product alone (composition claim) versus labeling and prescribing/use (method claims). No specific holdings can be cited without documents.
Which companies are challenging or licensing around US 9,642,911, and what litigation affects freedom to operate?
Important constraint: Company and litigation status are not provided. Identifying parties, Paragraph IV challenges, or settlements requires the patent’s litigation docket and/or FDA/Orange Book listing data tied to the patent number.
No accurate answer can be produced under the operating constraints.
What is the Orange Book status of US 9,642,911 for valganciclovir oral liquid?
Important constraint: Orange Book listing status depends on:
- whether the patent is listed for a specific NDA/ANDA product,
- patent type (drug substance, drug product, use),
- and the associated formulation/strength.
No Orange Book listing details are included in your prompt. Listing status cannot be stated accurately.
How strong is the patent estate for valganciclovir oral liquid given only claim 1?
Strength indicators from claim drafting (relative assessment).
- Claim 1 is tight because it locks down explicit per‑mL quantities and specific excipients.
- Narrow scope can reduce enforcement leverage against “close” generics unless they copy the formulation closely.
- However, if the claimed formulation is the marketed or licensed standard for a particular strength or pediatric liquid, enforcement can still be strong in that exact niche.
What would be needed for a full strength score (not provided).
- whether there are dependent claims that broaden or diversify coverage,
- whether there are manufacturing-process claims in the same patent family,
- whether claim 1 is part of a continuation with broader claims elsewhere.
Claim chart snapshot: would a hypothetical competitor infringe claim 1 if it changes excipients?
Infringement hinges on matching the claimed per‑mL composition. The following illustrates scope mechanics based on claim text:
| Element in claim 1 |
“Exact match” needed? |
Common design-around approach |
| Valganciclovir HCl |
Yes |
Use different salt/form or concentration |
| Povidone K30 2.00 mg/mL |
Yes |
Use different polymer or different amount |
| Fumaric acid 2.00 mg/mL |
Yes |
Change acidulant system and/or amount |
| Sodium benzoate 1.00 mg/mL |
Yes |
Change preservative system and/or amount |
| Sodium saccharin 0.25 mg/mL |
Yes |
Change sweetener system |
| Mannitol 57.80 mg/mL |
Yes |
Change tonicity agent/bulking |
| Tutti-frutti flavor 1.80 mg/mL |
Yes |
Change flavor system |
| Purified water 0.91 mL |
Yes |
Vehicle volume tied to solids; typically changes with all reformulations |
This table is limited to claim-logic derived from the provided claim 1 only.
Key Takeaways
- US 9,642,911 claim 1 is composition-specific: it covers a valganciclovir oral liquid with explicit per‑mL excipient identities and amounts.
- The claimed active loading is valganciclovir HCl 55.15 mg/mL, stated as 50 mg free base on a dry basis.
- A generic risk is highest when a challenger’s liquid matches the complete formulation “fingerprint”, not just the active ingredient.
- A broader US patent landscape (other patents, expiration timelines, Orange Book status, Paragraph IV challenges, litigation) cannot be reliably mapped from the information provided.
FAQs
1) Does US 9,642,911 cover all valganciclovir oral liquids or only this exact formulation?
It covers the liquid oral dosage form having the specific per‑mL composition recited in claim 1.
2) If a generic uses the same free-base valganciclovir dose but a different salt, does it still fall within claim 1?
Claim 1 specifies valganciclovir HCl, so a different salt/form would generally avoid that literal element.
3) Are excipient substitutions (e.g., different preservatives or sweeteners) likely to avoid claim 1?
Yes, because claim 1 recites specific excipients and specific mg/mL amounts, so substitutions can change whether the claimed composition is met.
4) Does the patent protect dosing instructions or only the product composition?
From claim 1 provided, the protection is directed to the composition of a liquid oral dosage form, not a method-of-use.
5) What is the most direct strategy to reduce infringement risk for a valganciclovir liquid generic?
Avoid matching the claimed complete per‑mL formulation, especially the excipient identities and quantities recited in claim 1.
References (APA)
- United States Patent 9,642,911. Claims as provided by user (claim 1 composition per mL for valganciclovir oral liquid).
