Patent: 4,062,942

Summary for Patent: 4,062,942

Title:	Induction of ovulation with partially desialylated human chorionic gonadotropin
Abstract:	Partially desialylated human Chorionic Gonadotropin is used after menotropin administration to induce ovulation.
Inventor(s):	Donini; Pietro (Rome, IT)
Assignee:	Serono Laboratories, Inc. (Boston, MA)
Application Number:	05/658,490
Patent Claims:	see list of patent claims

United States Patent 4,062,942: Claims Construction and US Patent Landscape for Partially Desialylated hCG in Sequential Ovulation Protocols

Executive summary US Patent 4,062,942 claims a specific ovulation-induction method: sequential administration of menotropins followed by partially desialylated human chorionic gonadotropin (hCG), with a defined desialylation degree of 15% to 35%. Dependent claims narrow the protocol to dose (5,000 IU/day hCG), and formulation handling via lyophilized partially desialylated hCG reconstituted in saline, including an excipient limitation (lactose). The landscape risk for any entrant using this approach turns on whether a product or method uses (i) the same sequential menotropin → hCG scheme, and (ii) hCG with a desialylation degree in the 15%–35% band, plus (iii) any required reconstitution and excipient choices if the method is practiced to the claimed narrow form.

The analysis below is limited to the information provided: the claim set for US 4,062,942. No Orange Book, prosecution history, examiner citations, assignment history, or litigation records were supplied, so they are not incorporated.

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What does US Patent 4,062,942 claim about partially desialylated hCG (15%–35% desialylation) for ovulation induction?

Bottom line Claim 1 is a method-of-treatment claim with three critical technical elements that must all be present to infringe:

1. Sequential administration of menotropins then hCG for inducing ovulation.
2. Use of partially desialylated hCG “as said human chorionic gonadotropin.”
3. Desialylation degree of 15% to 35%.

Claim 1 elements that drive infringement (and design-around)

1. “Sequential administration”

   • The claim requires a temporal sequence: menotropins first, then hCG.
   • A competing protocol that uses hCG concurrently with menotropins, uses a different ordering, or avoids the menotropin-to-hCG step sequence would not satisfy this limitation as written.

2. Menotropins

   • The claim is anchored to “menotropins” rather than gonadotropin-only alternatives. A method that substitutes different upstream stimulation agents would likely avoid the limitation depending on how “menotropins” are defined in the intrinsic record.

3. Partially desialylated hCG as the hCG

   • Infringement requires that the administered hCG is not native fully sialylated hCG but has been partially desialylated.

4. Desialylation degree: 15% to 35%

   • This is the most objective and testable numerical limitation.
   • Claims with a bounded percent range create a clear “off-ramp”: a product/process that produces hCG with desialylation below 15% or above 35% can fall outside claim 1 if the infringement analysis treats the degree as a strict numerical boundary.

Scope traps for challengers

• If a competitor’s product yields desialylation that overlaps the 15%–35% range, the method claim remains in play even if average desialylation is near the boundaries. In practice, the risk depends on batch variability and analytical method tolerance (not provided here).
• The claim language requires employing partially desialylated hCG “as said human chorionic gonadotropin.” That typically captures both clinical administration and any practice that uses that material in the menotropin→hCG method.

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How do the dependent claims narrow US 4,062,942 to dose and reconstitution/formulation steps?

Bottom line Dependent claims 2–5 narrow claim 1 to specific dosing and handling/formulation choices. These are important because they enable “partial” design-arounds: you can avoid dependent-claim infringement while still potentially infringing claim 1.

Claim 2: dose limitation

• “5000 IU human chorionic gonadotropin per day”.
• If a clinical protocol uses a different daily IU amount, it may avoid claim 2 but still practice claim 1 if the desialylation range and sequential method are met.

Design-around logic

• Lowering to sub- or supra-dose values avoids the dependent limitation but does not avoid claim 1.

Claim 3: lyophilized reconstitution into saline

• Requires hCG in the form of “a saline solution of lyophilized partially desialylated human chorionic gonadotropin.”
• This turns the claim from an abstract method into one tied to the drug material form and reconstitution.

Design-around logic

• If a competitor administers partially desialylated hCG not prepared as lyophilized reconstitution into saline (for example, different dosage form presentation), claim 3 may be avoided.

Claim 4: excipient-containing saline solution

• Requires that the saline solution contains an excipient.
• Without an excipient, claim 4 may not be met, even if saline and reconstituted lyophilized hCG are used.

Claim 5: excipient is lactose

• Locks excipient identity to lactose.
• This is a narrowest dependent formulation hook and often functions as a practical design-around target.

Design-around logic

• Using a different excipient system (or omitting lactose) can avoid claim 5 while preserving potential exposure under claims 1–4.

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Which aspects of US 4,062,942 are easiest to license or challenge?

Bottom line The enforceability and commercial defensibility of the claim set is driven by whether prior art disclosed: (i) sequential menotropins then hCG, (ii) desialylated hCG, and (iii) the specific 15%–35% desialylation range.

Strongest claim features (from an infringement perspective)

• The numerical desialylation range (15% to 35%) in claim 1 is the most concrete limitation.
• If prior art broadly taught “desialylated” hCG but not this band, claim 1 may be more defensible.

Most vulnerable points (from a validity perspective)

These are the elements that prior art can attack if the art exists:

• Sequential menotropins → hCG may be conventional fertility protocol design space.
• Partially desialylated hCG may have been known in the art as a biochemical modification for altered in vivo properties.
• Range selection can be challenged if prior art disclosed desialylation degrees or if routine optimization would land in the 15%–35% window.

The critical gap is not whether “desialylated hCG” existed, but whether the prior art would have motivated use of partially desialylated hCG within 15%–35% in that sequential menotropins/ovulation method.

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What is the likely US patent landscape around desialylated hCG and ovulation induction?

Bottom line Given only the claim text, the landscape can be mapped by claim-theme clusters rather than enumerating specific patent numbers (none were provided). The practical landscape typically divides into three buckets that overlap each other:

1) Method-of-use patents for ovulation induction using gonadotropin sequences

These claims generally cover:

• sequencing menotropins and hCG,
• specific administration schedules,
• clinical endpoints like ovulation induction.

US 4,062,942’s differentiator is the explicit use of partially desialylated hCG with a defined desialylation degree.

2) Product/process patents for modifying hCG glycosylation (desialylation)

These claims generally cover:

• producing desialylated hCG,
• defining the glycoform distribution or degree of desialylation,
• controlling manufacturing parameters.

If the landscape includes earlier or contemporaneous product claims, they may create a separate infringement or blocking position for any manufacturer, even if a method is changed.

3) Formulation and reconstitution system patents

These cover:

• lyophilized presentations,
• saline reconstitution,
• excipient systems including lactose.

US 4,062,942’s claims 3–5 sit in this space, but only as dependent narrowing to claim 1. They are most relevant when an accused product uses a matching presentation and excipient.

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How would a competitor design around US 4,062,942 without changing core ovulation practice?

Bottom line Design-around levers track the claim elements: sequence, desialylation range, dose, and formulation.

Design-around lever A: desialylation degree outside 15%–35%

• Move below 15% or above 35% desialylation.
• This is the cleanest path to avoid claim 1 if the numerical range is strictly construed.

Design-around lever B: break the menotropins → hCG sequencing

• Use a different sequence or avoid menotropins.
• This is typically harder clinically, but it is a direct claim element.

Design-around lever C: avoid the claimed dose

• Change from 5,000 IU/day.
• This avoids claim 2 but not claim 1.

Design-around lever D: change dosage form handling

• Avoid “lyophilized” reconstitution into saline.
• This avoids claim 3 but not claim 1.

Design-around lever E: change excipient identity away from lactose

• Use excipients other than lactose or different excipient composition.
• This avoids claim 5 but not claims 1–4 (unless excipient identity is required to satisfy those claims as well, which it is not based on the text provided).

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What claims in US 4,062,942 are most likely to be litigated: numerics, sequence, or formulation?

Bottom line For a clinical/generic or follow-on biologics-style contest, dispute focus usually concentrates on:

1. Whether the administered hCG meets the 15%–35% desialylation definition.
2. Whether the method sequence matches menotropins followed by hCG.
3. If product presentation is aligned, whether reconstitution/formulation matches claims 3–5.

Why numerics matter

• Numerical ranges are measurable. They often drive expert testimony on assay methodology and batch qualification.

Why sequence matters

• The method claim ties to a clinical protocol. Any deviation changes exposure.

Why formulation matters

• Formulation features (lyophilized, saline, lactose) often determine narrower dependent-claim infringement and can be litigated if product presentation is close.

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What patent strength can be inferred for US 4,062,942 based on claim structure alone?

Bottom line The claim set has a relatively tight “center of gravity” around a biochemical parameter (desialylation %) combined with a clinical sequence (menotropins then hCG). Tightness can strengthen enforceability against close substitutes, but also creates validity exposure if the range appears to be an optimization of a known parameter without a clear non-obvious boundary.

Strength signals in the claim text

• Single decisive biochemical numeric constraint (15%–35%) in claim 1.
• Dependent claims narrow to specific practical execution details (dose; lyophilized saline; lactose excipient).

Weakness signals in the claim text

• Claim 1 still leaves room for arguments that the inventive contribution is only a substitution of a known variant of hCG into an otherwise known ovulation induction protocol.
• Without intrinsic support (not provided), numerical range selection can be attacked as routine optimization.

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How many patents could cover the same clinical outcome: multiple overlapping estates?

Bottom line Even without enumerating patents, the claim structure implies that multiple independent or complementary patents may exist across:

• method-of-use,
• product modification,
• formulation presentation,
• manufacturing/control of desialylation.

For a market entrant, this creates a typical multi-layer freedom-to-operate (FTO) stack:

• a product that uses desialylated hCG could implicate product/glycoform patents,
• a protocol using menotropins then hCG could implicate method patents,
• a lyophilized lactose/saline presentation could implicate formulation patents.

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Key Takeaways

• US 4,062,942 Claim 1 covers ovulation induction via sequential menotropins then hCG where the hCG is partially desialylated with 15%–35% desialylation.
• Dependent claims further require 5,000 IU/day, and narrow dosage presentation to lyophilized partially desialylated hCG reconstituted in saline, including lactose as an excipient.
• The highest-risk infringement hook is the 15%–35% desialylation range coupled with the menotropins-to-hCG sequential protocol.
• The most straightforward design-around is to use hCG outside the 15%–35% desialylation band; second-order design-arounds target dose, reconstitution format, and lactose excipient.

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FAQs

1) If a competitor uses hCG with 14% desialylation, does it avoid US 4,062,942?
It avoids claim 1 on its face because claim 1 requires 15% to 35% desialylation.

2) Does changing the daily IU dose avoid infringement of US 4,062,942?
Changing dose avoids claim 2 but not claim 1, unless the protocol also departs from the desialylation range and sequential menotropins→hCG structure required by claim 1.

3) Is lactose essential for infringement of the core method claim?
No. Lactose is required only for dependent claim 5.

4) If a product uses partially desialylated hCG but not after menotropins, is it still covered?
Not under claim 1 as written, because claim 1 requires sequential administration of menotropins followed by hCG.

5) Can a competitor avoid claim 3 by using a non-lyophilized liquid form?
Yes. Claim 3 requires saline solution of lyophilized partially desialylated hCG, so a different presentation can avoid claim 3 while still potentially implicating claim 1.

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References

1. United States Patent 4,062,942. (Claim text provided in prompt).

Details for Patent 4,062,942

Applicant	Tradename	Biologic Ingredient	Dosage Form	BLA	Approval Date	Patent No.	Expiredate
Ferring Pharmaceuticals Inc.	NOVAREL	chorionic gonadotropin	For Injection	017016	January 15, 1974		1996-02-17
Ferring Pharmaceuticals Inc.	NOVAREL	chorionic gonadotropin	For Injection	017016	December 27, 1984		1996-02-17
Ferring Pharmaceuticals Inc.	NOVAREL	chorionic gonadotropin	For Injection	017016	February 15, 1985		1996-02-17
Ferring Pharmaceuticals Inc.	NOVAREL	chorionic gonadotropin	For Injection	017016	February 16, 1990		1996-02-17
Bel-mar Laboratories, Inc.	CHORIONIC GONADOTROPIN	chorionic gonadotropin	Injection	017054	March 26, 1974		1996-02-17
Fresenius Kabi Usa, Llc	CHORIONIC GONADOTROPIN	chorionic gonadotropin	For Injection	017067	March 05, 1973		1996-02-17