US Patent 4,262,003: Scope, Claims, Expiration, and Scopolamine Transdermal Patent Landscape

US Patent 4,262,003 covers the core method used by the original scopolamine transdermal patch: applying scopolamine base to intact skin, delivering an initial loading pulse, and then maintaining a substantially constant delivery rate for prolonged control of nausea and vomiting. The patent issued to Alza Corporation on April 14, 1981, and its ordinary 17-year patent term expired on April 14, 1998. The claims therefore no longer create an enforceable U.S. patent barrier.

The patent remains commercially important because its claim structure maps closely to the Transderm Scop delivery concept: mastoidal application, controlled transdermal delivery, a total scopolamine dose of approximately 0.1 to 2.5 mg, and delivery rates within the claimed hourly ranges.

What does US Patent 4,262,003 protect?

The patent protects a transdermal method of treating nausea and emesis with scopolamine base. Its central limitations are:

Scopolamine must be administered to unbroken skin.
Administration begins with an initial pulse of approximately 10 to 200 micrograms per square centimeter.
Delivery then proceeds at a substantially constant rate of approximately 0.3 to 15 micrograms per hour.
Treatment continues for as long as therapy is required.

The patent is a method-of-treatment patent, not simply a composition or patch-device patent. Infringement historically would have depended on the accused product and instructions being used in a way that satisfied the claimed delivery profile.

Claim 1: Core transdermal delivery method

Claim 1 is the broadest independent claim. It requires:

The therapeutic agent to be scopolamine base.
Application to intact, unbroken skin.
An initial loading pulse of approximately 10 to 200 micrograms per square centimeter.
A subsequent substantially constant release rate of approximately 0.3 to 15 micrograms per hour.
Treatment of nausea and emesis over a prolonged period.

The claim is directed to pharmacokinetic delivery behavior rather than only to the physical construction of a patch. A patch could fall within the claim even if its adhesive, backing layer, reservoir, or membrane structure differed from the structures described in the specification, provided the resulting use met the claimed dose and rate limitations.

The phrase “about” gives numerical ranges some practical tolerance, but it does not eliminate the need to prove that the accused delivery profile falls within, or is equivalent to, the claimed parameters. “Substantially constant rate” would ordinarily be assessed against the delivery profile over the relevant treatment interval, not against perfect mathematical uniformity.

Claim 2: Vestibular-disorder treatment and pretreatment

Claim 2 narrows claim 1 by requiring that the nausea or emesis be induced by a vestibular disturbance and that administration begin at least approximately three hours before the disturbance requires therapy.

This limitation directly addresses motion sickness and related vestibular conditions. The claim is narrower than claim 1 because it adds both:

A specific cause of nausea or emesis; and
A pretreatment timing requirement.

A product used only after symptoms begin, or for postoperative nausea unrelated to a vestibular disturbance, would not satisfy claim 2 unless the facts supported the required vestibular and timing limitations.

Claim 3: Total scopolamine dose

Claim 3 limits the total quantity of scopolamine base administered to 0.1 to 2.5 mg.

This limitation is commercially significant because a typical scopolamine transdermal system has historically contained more drug than it releases. The claim focuses on the total quantity administered, rather than necessarily the total quantity loaded into the patch. The distinction matters because a device can contain a reservoir exceeding the amount ultimately delivered through the skin.

A system delivering less than 0.1 mg or more than 2.5 mg would fall outside the literal range of claim 3, subject to the interpretation of “about” and possible equivalents. Claim 3 does not require a particular patch architecture.

Claim 4: Mastoidal application

Claim 4 requires application to skin located at the mastoidal area, behind or near the ear.

The mastoidal site is important because the skin in that area was selected for practical transdermal delivery and sustained adhesion. The claim is narrower than claim 1 but closely aligned with the labeled use of the original scopolamine patch.

A patch applied to the upper arm, chest, abdomen, or another location would not literally meet claim 4. It could still potentially fall within claim 1 if the delivery profile and other limitations were satisfied.

Claim 5: Non-mastoidal skin and permeation enhancers

Claim 5 covers administration at a body site other than the mastoidal area when the skin is treated with an effective amount of a permeation-enhancing agent.

This claim addresses the possibility that skin outside the mastoidal region may require chemical assistance to achieve the claimed delivery rate. It combines:

A non-mastoidal administration site;
Scopolamine delivery through intact skin; and
Use of an effective permeation enhancer.

The claim does not require one particular enhancer. The operative requirement is that the agent be effective in facilitating delivery at the selected site.

Claim 6: Named permeation enhancers

Claim 6 narrows claim 5 to three specified agents:

Dimethyl lauramide;
Dimethyl sulfoxide, commonly known as DMSO; and
Dodecyl pyrrolidone.

This is a closed Markush-style selection from the three listed compounds. An accused product using another enhancer would not literally satisfy claim 6, although it could still implicate claim 5 if the other limitations were met.

DMSO is the most recognizable compound in the list. Dimethyl lauramide and dodecyl pyrrolidone reflect the patent’s broader formulation work directed to improving skin penetration outside the preferred mastoidal site.

Claim 7: Narrower dose and rate parameters

Claim 7 narrows claim 1 by requiring:

An initial pulse of approximately 50 to 150 micrograms per square centimeter; and
A substantially constant delivery rate of approximately 5 to 15 micrograms per hour for adults; or 3 to 10 micrograms per hour for children.

The adult range is narrower than claim 1’s 0.3 to 15 micrograms per hour range. The pediatric range partly overlaps the adult range but extends lower, from approximately 3 micrograms per hour.

Claim 7 is important for claim-chart analysis because a product outside the narrower initial-pulse range may still fall within claim 1. Similarly, a pediatric delivery rate between 3 and less than 5 micrograms per hour could fall within the pediatric portion of claim 7 while remaining outside the adult portion.

Claim 8: Preferred site plus claim 7 parameters

Claim 8 depends on claim 7 and requires the skin to be located at the mastoidal area.

It is the narrowest claim in the set. It combines:

The narrower loading-pulse range;
The adult or pediatric maintenance-rate ranges; and
Mastoidal administration.

A product would need to satisfy every limitation of claim 7 and the mastoidal-site limitation to infringe claim 8 literally.

How do the claims compare?

Claim	Principal limitation	Relative breadth	Commercial relevance
1	Scopolamine through intact skin with loading pulse and sustained rate	Broadest	Core transdermal method
2	Vestibular nausea plus pretreatment at least three hours before need	Narrow	Motion-sickness use
3	Total administered dose of 0.1 to 2.5 mg	Narrow	Aligns with patch dosing
4	Mastoidal application	Narrow	Aligns with behind-the-ear use
5	Non-mastoidal site with permeation enhancer	Narrow	Alternative body-site delivery
6	Dimethyl lauramide, DMSO, or dodecyl pyrrolidone	Narrowest enhancer claim	Specific formulation strategy
7	Narrower loading pulse and adult/pediatric rates	Narrow	Pharmacokinetic limitation
8	Claim 7 plus mastoidal site	Narrowest overall	Preferred commercial configuration

When did US Patent 4,262,003 lose exclusivity?

US Patent 4,262,003 expired in 1998 under the pre-Uruguay Round patent-term rule of 17 years from issuance. The relevant dates are:

Event	Date
Patent issued	April 14, 1981
Statutory term under pre-URAA rule	17 years from issuance
Ordinary expiration	April 14, 1998
Current enforceability	None

The patent predates the 20-year-from-earliest-effective-filing-date term that applies to most later U.S. utility patents. No current generic manufacturer needs to overcome this patent through a Paragraph IV certification because the patent is expired.

Patent expiration eliminates enforceability but does not erase the patent’s historical relevance. The specification and claims may remain relevant to:

Prior-art analysis;
Obviousness disputes involving later scopolamine delivery systems;
Claim construction in related patents;
Regulatory-history analysis;
Freedom-to-operate reviews concerning later patents.

What FDA product did the patent support?

The patent is associated with the transdermal scopolamine technology commercialized as Transderm Scop. FDA-approved labeling describes a scopolamine transdermal system applied behind the ear for prevention of nausea and vomiting associated with motion sickness and postoperative recovery [2].

The product concept corresponds closely to the patent claims:

Product characteristic	Relationship to US 4,262,003
Scopolamine active ingredient	Satisfies the active-agent concept
Behind-the-ear application	Corresponds to the mastoidal limitation
Multi-day delivery	Corresponds to prolonged therapy
Controlled transdermal release	Corresponds to the sustained-rate limitation
Motion-sickness indication	Corresponds to vestibular disturbance
Pretreatment before travel or exposure	Corresponds to claim 2

The patch contains a quantity of scopolamine sufficient to support delivery over several days. The loaded amount and delivered amount should be distinguished in any technical claim analysis.

What is the Orange Book status of scopolamine transdermal products?

The FDA Orange Book identifies approved drug products and, where applicable, patent and regulatory-exclusivity information submitted by the New Drug Application holder [1]. For an old product such as Transderm Scop, the principal commercial patent risk from US 4,262,003 has ended because the patent expired in 1998.

The regulatory position is therefore different from the patent position:

The original NDA remains a historical FDA approval record.
The original patent is expired.
FDA approval of an ANDA or competing product is not blocked by this patent.
Any current patent issue must be evaluated against later patents, not against US 4,262,003.
Regulatory exclusivity associated with the original approval has also expired.

An Orange Book listing, if any historical entry remains visible in archived or current records, does not revive an expired patent. FDA listing status and patent enforceability are separate questions.

Were Paragraph IV challenges required for this patent?

A Paragraph IV certification is used when an ANDA applicant asserts that a listed patent is invalid, unenforceable, or will not be infringed. Because US 4,262,003 expired in 1998, an applicant seeking approval for a later scopolamine transdermal product would not need to challenge it under Paragraph IV.

The relevant certification would generally be:

Paragraph III if a listed patent remained unexpired and the applicant accepted delayed approval; or
Paragraph IV if the applicant challenged an unexpired listed patent.

For US 4,262,003, neither route is presently necessary because the patent term has ended. Current ANDA disputes, if any, would concern later patents covering formulation, adhesive composition, manufacturing, device architecture, or other product-specific features.

What patent landscape followed US 4,262,003?

The surrounding scopolamine patent landscape has historically included four technical categories.

Transdermal system architecture

Later patents and patent families addressed:

Drug reservoirs;
Rate-controlling membranes;
Adhesive layers;
Backing films;
Release liners;
Patch dimensions;
Scopolamine stability;
Skin contact and adhesion.

These patents could provide protection independent of the method claims in US 4,262,003. Their terms, however, were also generally tied to filing dates and many early Alza-era patents have expired.

Scopolamine formulations

Formulation claims may cover:

Scopolamine base versus scopolamine salts;
Solvent systems;
Polymer matrices;
Adhesive compositions;
Permeation enhancers;
Stabilizers;
Drug crystallization control.

Claim 6 of US 4,262,003 is an early example of a formulation-related limitation, but it is not a general monopoly over every scopolamine formulation.

Method-of-use patents

Later method claims could address:

Motion sickness;
Postoperative nausea and vomiting;
Specific surgical procedures;
Pediatric or geriatric dosing;
Combination therapy;
Timing of administration;
Treatment of particular vestibular disorders.

US 4,262,003 is relatively broad in covering nausea and emesis, but claim 2 specifically narrows the method to vestibular disturbance and advance administration.

Manufacturing and device patents

Potential later barriers may involve:

Coating and laminating processes;
Reservoir filling;
Control of scopolamine loading;
Patch uniformity;
Adhesive manufacturing;
Packaging and moisture control;
Transdermal flux testing.

These rights would be evaluated separately from the expired therapeutic-method claims. Manufacturing patents can affect supply-chain freedom to operate even where the core active ingredient and clinical use are unpatented.

How strong is the patent estate for scopolamine transdermal delivery today?

The estate represented by US 4,262,003 is legally weak today because the patent is expired. Its historical claim coverage was strong for the original commercial concept because the claims captured the main variables that distinguish a controlled transdermal system from ordinary topical administration:

Drug identity;
Intact-skin delivery;
Initial loading pulse;
Sustained delivery rate;
Total delivered quantity;
Application site;
Permeation enhancement;
Treatment timing.

The commercial risk has shifted from the expired core method to any later, still-unexpired patents. The most relevant current searches would focus on the specific product formulation, patch construction, manufacturing process, and approved labeling of the competing product.

What generic launch risks exist?

US 4,262,003 does not create a current generic launch risk. A generic scopolamine transdermal product can enter without waiting for this patent to expire because the expiration occurred more than two decades ago.

The remaining launch risks are more likely to arise from:

Bioequivalence and adhesion performance.
Demonstration of comparable transdermal delivery.
Control of scopolamine content and residual drug.
Manufacturing consistency.
Product-specific later patents.
FDA labeling and safety requirements.
Commercial availability of suitable patch materials.

For transdermal products, regulatory and technical barriers can be more important than the expired core patent. A generic developer must generally demonstrate that the product performs consistently as a patch, not merely that it contains the same active ingredient.

Which companies are relevant to the competitive landscape?

The original technology was associated with Alza Corporation, the pioneer of several controlled transdermal delivery systems. Transderm Scop was later commercialized through successor and licensee arrangements involving major pharmaceutical companies. Generic competition has developed through ANDA-based products after the original patent and regulatory exclusivity periods ended.

The competitive landscape has three layers:

Layer	Competitive basis
Branded scopolamine patch	Brand recognition, supply reliability, physician familiarity
Generic scopolamine patch	Price, reimbursement, pharmacy substitution
Alternative antiemetic products	Oral, injectable, buccal, or other delivery routes

Biosimilar risk is not relevant. Scopolamine is a small-molecule drug, not a biologic, so competing products are regulated as generic drugs rather than biosimilars.

What litigation and settlement issues affect the patent?

US 4,262,003 cannot support a new infringement action because it expired in 1998. Any historical litigation involving the patent would have had to occur during its enforceable term. A settlement entered during that period would not extend the patent beyond its statutory expiration date.

Current disputes involving scopolamine transdermal products would more likely concern:

Later formulation or device patents;
ANDA Paragraph IV certifications against unexpired patents;
Manufacturing patents;
Trade dress or trademark rights;
Product liability;
FDA approval or labeling issues.

No settlement involving US 4,262,003 can create present patent exclusivity after expiration.

Key Takeaways

US Patent 4,262,003 covers controlled transdermal administration of scopolamine for prolonged treatment of nausea and emesis.
Claim 1 is the core method claim and requires an initial skin-delivery pulse followed by a substantially constant delivery rate.
Claims 2 through 8 narrow the invention by vestibular indication, pretreatment timing, total dose, mastoidal location, permeation enhancers, and adult or pediatric delivery rates.
The patent issued on April 14, 1981, and expired on April 14, 1998.
It no longer blocks generic scopolamine transdermal products.
The patent closely tracks the commercial Transderm Scop concept.
Biosimilar risk is inapplicable because scopolamine is a small molecule.
Current freedom-to-operate analysis must focus on later patents covering patch architecture, formulations, manufacturing, and product-specific methods.
FDA approval and Orange Book status are separate from enforceability of this expired patent.
The primary present commercial barriers are regulatory performance, transdermal manufacturing, product reliability, and any unexpired later patent rights.

FAQs About US Patent 4,262,003 and Scopolamine Patches

Does US Patent 4,262,003 still protect the Transderm Scop patch?

No. The patent expired on April 14, 1998. It may remain relevant as prior art and historical evidence but cannot presently be enforced.

Did US Patent 4,262,003 cover oral scopolamine?

No. The claims require administration of scopolamine base to unbroken skin. Oral, injectable, ophthalmic, or other non-transdermal administration is outside the literal scope of these claims.

Does a scopolamine patch applied to the arm infringe claim 4?

Not literally, because claim 4 requires the mastoidal area. An arm-applied product could still require analysis under claim 1 or claim 5 if it uses transdermal delivery and, for claim 5, an effective permeation enhancer.

Are scopolamine transdermal systems eligible for generic substitution?

Yes, subject to FDA approval and the applicable state substitution rules. Scopolamine transdermal products are small-molecule drug products, not biosimilars.

What is the most important technical limitation in claim 1?

The most consequential limitation is the combination of an initial loading pulse and a subsequent substantially constant delivery rate between approximately 0.3 and 15 micrograms per hour. That delivery profile distinguishes the claimed method from ordinary topical application.

References

U.S. Food and Drug Administration. (2024). Approved drug products with therapeutic equivalence evaluations: The Orange Book. U.S. Department of Health and Human Services.
U.S. Food and Drug Administration. (2023). Transderm Scop (scopolamine) transdermal system prescribing information. U.S. Department of Health and Human Services.
U.S. Patent and Trademark Office. (1981). U.S. Patent No. 4,262,003.
World Intellectual Property Organization. (n.d.). Patent term and duration principles for pre-URAA United States patents. WIPO.

Details for Patent: 4,262,003

Summary for Patent: 4,262,003