Patent: 6,080,395

Summary for Patent: 6,080,395

Title:	Method and composition for topical treatment of damaged tissue using histamine as active ingredient
Abstract:	A pharmaceutical composition of water, water soluble vinyl polymer gel, amine alcohol dispersant and IEP is used topically to treat herpes labialis and aphthous stomatitis lesions, and also to treat herpes genitalis, chicken pox, allergic conjunctivitis, giant papillary conjunctivitis, stomatitis secondary to chemotherapy, thermal burn, sunburn, and decubitus ulcers and shingles.
Inventor(s):	Jack; Bruce A. (Albuquerque, NM), White; B. Thomas (Albuquerque, NM)
Assignee:	Maxim Pharmaceutical, Inc. (San Diego, CA)
Application Number:	09/196,840
Patent Claims:	see list of patent claims

Comprehensive patent landscape analysis for US Patent 6,080,395 (topical histamine; excludes histamine phosphate)

US 6,080,395 is a late-1990s US patent that claims (i) topical delivery methods using histamine (excluding histamine phosphate) for a broad set of skin, mucous membrane, and conjunctival disorders, and (ii) topical compositions (including emulsions) with a specific histamine concentration range. The claim set is built around four main technical “hooks”: (1) topical histamine delivery as the active, (2) exclusion of histamine phosphate, (3) optional use of histamine precursor or prodrug, and (4) defined formulation features (concentration window; emulsion; neutralizer/emulsifier; preservative options; and certain product forms). The resulting enforceability profile is highly dependent on claim construction (what counts as “histamine precursor/prodrug,” what qualifies as “topical delivery” to the listed membranes) and on whether competitors use the same histamine species and the same formulation window or functional equivalents.

What patents protect topical histamine delivery for skin and mucous membrane disorders?

US 6,080,395 covers both methods and compositions for topical histamine use across dermatologic, mucosal, and ocular surface indications. The scope is not limited to a single disease or mechanistic justification. The claims instead form a cross-indication “platform” around topical histamine (not histamine phosphate) delivered at low concentration.

What are the core claim elements in US 6,080,395?

Independent claim themes

• Method: Topically deliver an effective dose of histamine (not histamine phosphate) to a subject with a disorder of skin, mucous membranes, or conjunctival membranes.
• Composition: Composition containing histamine in a specific weight % range (approx. 0.00325 to 0.0067% by weight) in a pharmaceutically acceptable topical carrier, with histamine not being histamine phosphate.
• Manufacturing method: Make an emulsion with carrier + histamine within the concentration window, excluding histamine phosphate.

Key dependent expansions

• Disease list: Viral diseases (herpes labialis/genitalis/zoster/varicella zoster), aphthous stomatitis/oral mucositis, allergic conjunctivitis/giant papillary conjunctivitis, and injuries (photodermatitis, thermal burns, decubitus ulcers).
• Alternate histamine source forms: histamine precursor and/or histamine prodrug, each explicitly “not histamine phosphate.”
• Delivery/packaging: effective dose via a unidose dispenser.
• Formulation: further includes neutralizer + emulsifying agent (including amino alcohol emulsifier); preservative selection (propylparaben or methylparaben); and dosage forms such as lotion, gel, or mouthwash.

What does the “histamine is not histamine phosphate” limitation do to infringement risk?

This limitation narrows the active species. A competitor that uses histamine phosphate as the topical ingredient is outside the literal scope of the claims. But it does not automatically eliminate infringement risk against competitors using a different salt form (e.g., histamine dihydrochloride) because the claims distinguish only “histamine phosphate.” Practically, infringement hinges on whether the accused ingredient is legally and factually treated as “histamine phosphate” versus another histamine chemical form, plus how “histamine,” “precursor,” and “prodrug” are construed.

What other patents likely cluster around this chemical and formulation concept?

While specific co-pending/adjacent patents depend on assignee and prosecution history, the claim structure suggests a typical landscape in which the most litigable overlap will be:

• Topical histamine for herpesvirus, aphthous/oral mucosa, conjunctivitis using histamine or close analogs.
• Formulation patents covering low-concentration histamine emulsions, gels, lotions, or mouthwashes with parabens and emulsifiers.
• Process/manufacturing patents around forming emulsions at specific weight % ranges and incorporating neutralizers/emulsifiers.
• Prodrug/precursor patents claiming alternative chemical forms that release histamine in skin/mucosa.

The risk for competitors is that broad method claims can be asserted even where formulations differ, as long as the accused product still delivers “histamine” (or claimed “precursor/prodrug”) topically to the covered tissues and diseases.

How strong are the claims of US 6,080,395 against design-arounds?

Strength drivers

• Low concentration range is explicitly claimed for compositions and manufacturing method. That can support enforcement where a competitor matches the concentration window and formulation concept (emulsion with carrier).
• Disease recitation in dependent claims helps define a useful adjudicative anchor: a competitor’s labeled indication or actual use for those disorders can matter for method claims.
• Histamine not histamine phosphate is an explicit negative limitation that gives clear boundaries if competitors choose phosphate-based approaches.

Weakness drivers

• Broad disease coverage across viral, mucosal, ocular, and burn/ulcer contexts can face validity and enforceability challenges related to lack of clear enabling disclosure or lack of persuasive technical differentiation over prior art teaching topical histamine for inflammation or immunomodulation. The more broadly a claim spans, the more difficult it is to defend against “predictable use” and obviousness theories where topical histamine is known.
• Functional “effective dose” without numerical dose boundaries for the method claim can increase non-infringement defenses and can complicate validity analysis. Competitors can argue they deliver too little to meet “effective dose,” or that their delivery is pharmacokinetically insufficient on the claimed tissues.
• Ambiguity risk for “precursor” and “prodrug”: if the patent does not clearly define particular precursor/prodrug structures, competitors can argue their chemistry is not a “precursor/prodrug” within claim meaning, or that it is not designed to convert to histamine under physiological conditions.

When does US 6,080,395 expire and when does exclusivity end?

US utility patents in force in the US generally expire 20 years from the earliest effective US non-provisional filing date (subject to term adjustments and patent-specific adjustments under older rules). This analysis cannot provide an exact expiration date from the claim text alone. No filing date, priority date, or term adjustment is provided in the prompt.

What patents overlap for herpes, aphthous, mucositis, and conjunctivitis using topical histamine?

The claim set groups indications into four buckets:

1. Viral diseases: herpes labialis/genitalis, herpes zoster, varicella zoster.
2. Oral mucosal disorders: aphthous stomatitis, oral mucositis.
3. Ocular allergy/irritation: allergic conjunctivitis, giant papillary conjunctivitis.
4. Injury-related skin/membrane damage: photodermatitis, thermal burns, decubitus ulcers.

Practical litigation impact: indication-specific use patterns

For method-of-use claims, the strongest infringement theories tend to use:

• patient instructions matching the claimed therapeutic setting,
• packaging/labeling that instructs for those disorders,
• and real-world use consistent with those instructions.

A competitor can reduce method-claim exposure by:

• limiting labeling away from the listed disorders,
• restricting sales to indications not covered by dependent claims,
• or changing the delivery target in a way that avoids the claim’s tissue categories (skin vs mucous membranes vs conjunctival membranes).

What formulations are protected by US 6,080,395?

US 6,080,395 composition claims are constrained by:

• a histamine concentration window: ~0.00325 to 0.0067% w/w, and
• topical acceptable carriers adapted for topical delivery, and
• explicit exclusion: histamine is not histamine phosphate.

Dependent composition and manufacturing claims expand specific formulation features:

• neutralizer + emulsifying agent (including amino alcohol emulsifiers),
• preservative: propylparaben or methylparaben,
• dosage forms: lotion, gel, mouthwash,
• emulsion formation in the manufacturing method.

Does the concentration window create a carve-out?

Yes. If an accused product uses histamine outside the claimed 0.00325 to 0.0067% by weight range, the composition claim literal scope is less likely to be met. However, the method claims do not include that concentration window explicitly; they include “effective dose.” That means formulation engineers should expect that:

• composition-count exposure can be reduced by shifting concentration,
• but method-count exposure may persist if “effective dose” is argued to be met even with a different concentration window.

Which companies are challenging topical histamine patents and how do Paragraph IV or biosimilar-style challenges map?

This question requires specific Orange Book listings, FDA regulatory documents, and identified generic/biosimilar challengers. None are provided in the prompt. Without those data, it is not possible to produce an accurate, litigation-grade mapping of Paragraph IV or generic entry risk against US 6,080,395.

What is the Orange Book status of US 6,080,395?

Orange Book status cannot be determined from the claim text. The patent’s regulatory linkage depends on whether a listed NDA/ANDA cites it, and on the exact product-association. The prompt provides no NDA/ANDA number, listed dosage form, or patent listing identifiers.

What generic entry risks exist for topical histamine products that avoid histamine phosphate?

Even without Orange Book linkage, the generic entry risk logic for this patent is straightforward:

Most relevant design-around vectors

• Use histamine phosphate: the claims explicitly exclude it. This is the strongest literal carve-out for active-species design-arounds.
• Change histamine chemical form: if competitors use a different histamine salt/derivative not treated as “histamine phosphate,” they can still fall within “histamine” unless claim construction excludes it.
• Adjust concentration outside 0.00325 to 0.0067% w/w: reduces composition claim exposure; method claims may remain.
• Avoid claimed formulation architecture: if the patented emulsion features are central for particular dependent claims, competitors can alter excipients and processing to move away from claimed “emulsion” or “amino alcohol emulsifying agent” features.
• Avoid covered disease claims: for method-of-use, narrowing indications and labeled usage can reduce enforceability in practice.

Key risk remains: “effective dose” method claims

Even if composition concentration moves outside the claimed range, method claims can be asserted if an accused product delivers “effective dose” histamine topically to the covered tissue sites for the listed disorders.

How does US 6,080,395 compare with other topical immunomodulation patents?

US 6,080,395 is distinctive because it claims an older small-molecule immunological mediator (histamine) as a topical therapeutic, with a stated exclusion of histamine phosphate and defined concentration ranges for compositions. Compared with more modern platform patents, it typically offers:

• narrower chemical exclusion,
• narrower concentration window for composition claims,
• but broad disease and tissue categories for method claims.

This structure often leads to:

• enforcement strength focused on specific histamine-containing formulations, and
• litigation leverage on method claims if the defendant’s product is used for the listed indications with an “effective dose.”

Claim chart readiness: where infringement arguments usually concentrate

For composition infringement

• Accused product contains histamine (not histamine phosphate).
• Histamine concentration is within 0.00325 to 0.0067% by weight.
• Product is a topical delivery composition in a pharmaceutically acceptable carrier.

For method infringement

• Accused product is topically delivered to skin/mucous/conjunctival membranes.
• Intended or actual use is for disorders listed in dependent claims.
• Delivered histamine is not histamine phosphate.
• Delivered dose is “effective.”

For manufacturing infringement

• Process forms an emulsion containing carrier + histamine at the claimed concentration window.
• Histamine used is not histamine phosphate.

Key takeaways

• US 6,080,395 is centered on topical histamine therapy with a hard exclusion for histamine phosphate and a defined low-concentration range for compositions (and emulsion-making processes).
• The strongest literal enforcement leverage is in products that replicate the concentration window and formulate histamine in an emulsion with the claimed excipient categories.
• The biggest practical exposure persists for method-of-use, where “effective dose” is not numerically bounded and where covered indications (viral herpes/zoster/varicella, aphthous/oral mucositis, allergic/giant papillary conjunctivitis, and injury-related skin disorders) are broad.
• Clearer design-arounds include using histamine phosphate (avoids literal claim language) and shifting formulation concentration outside the claimed window, paired with careful indication management to reduce method-claim enforceability.

FAQs

1. Does US 6,080,395 cover histamine salts other than histamine phosphate?
The claims explicitly exclude histamine phosphate, so other histamine salt forms could still be argued as “histamine” unless claim construction or specification limits apply.

2. If a topical histamine product is formulated outside 0.00325 to 0.0067% w/w, does it still risk method-claim infringement?
Yes. Composition claims track the concentration window, but method claims use “effective dose,” so concentration shifts do not automatically eliminate method exposure.

3. Can a manufacturer reduce risk by removing the claimed indications from labeling?
Method claims are highly sensitive to intended and actual use. Narrowing labeled indications away from the listed disorders reduces infringement leverage.

4. What is the significance of the “unidose dispenser” limitation?
It narrows dependent method claim scope. If a competitor uses multi-dose containers or different dispensing systems, the “unidose dispenser” limitation may be avoided for that dependent claim.

5. Do “histamine precursor” and “histamine prodrug” broaden US 6,080,395 beyond direct histamine?
Yes. Dependent claims expand coverage to precursor/prodrug forms that still are “not histamine phosphate,” increasing the number of histamine-derived actives that could be argued to fall within the claim set.

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References (APA)

No external sources were cited because the prompt provides only the US 6,080,395 claim text and does not include bibliographic data (filing/priority dates, assignee, USPTO publication identifiers, prosecution history), FDA product linkages (NDA/ANDA), or Orange Book listings.

Details for Patent 6,080,395

Applicant	Tradename	Biologic Ingredient	Dosage Form	BLA	Approval Date	Patent No.	Expiredate
Alk-abello, Inc.	HISTATROL	positive skin test control-histamine	Injection	103754	September 29, 1950		2018-11-20
Jubilant Hollisterstier Llc	N/A	positive skin test control-histamine	Injection	103891	March 13, 1924		2018-11-20