Scope and Patent Landscape for US Patent 5,866,581 (Famciclovir/Penciclovir for Post-Herpetic Neuralgia, US Claims 1–21)

US Patent 5,866,581 covers specific therapeutic and prophylactic uses of famciclovir or penciclovir for post-herpetic neuralgia (PHN), including treatment timing windows after rash onset, duration (7 days), and treatment in older age strata. The claims are directed to method-of-treatment and method-of-prophylaxis with particular dosing regimens (including famciclovir 250 mg/500 mg/750 mg and multiple daily frequency options). From a freedom-to-operate and litigation-risk perspective, the most infringement-relevant claim elements are: (i) PHN indication, (ii) drug identity (famciclovir or penciclovir), (iii) timing relative to rash onset (≤72 hours, ≤48 hours), and (iv) specified dosing/frequency combinations for famciclovir.

What is US Patent 5,866,581 and what PHN uses does it claim?

Short answer: The patent claims methods for treating PHN in mammals (including humans) using famciclovir or penciclovir, and prophylactic treatment methods in humans, with additional limitations for early treatment timing, treatment duration, patient age, and specific famciclovir dosing regimens.

Core claim structure (independent and dependent claims)

Claim 1 (treatment method, broad baseline)

“A method for the treatment of PHN in mammals… administering an effective amount of famciclovir or penciclovir… or pharmaceutically acceptable salt.”

Claim 15 (prophylactic method, baseline)

“A method for prophylactic treatment of PHN in a human… administering an effective prophylactic amount of famciclovir or penciclovir…”

Claims 2–4 (timing and duration)

Claim 2: treatment “within 72 hours of rash onset”
Claim 3: treatment “within 48 hours of rash onset”
Claim 4: treatment period “7 days”

Claims 5–7 (age-limited subgroups)

Claim 5: patients “greater than 50 years”
Claim 6: “greater than 60 years”
Claim 7: “greater than 70 years”

Claims 8–14 (famciclovir-specific dosing configurations)

Claim 8: compound is famciclovir
Claim 9: famciclovir at 250 mg, 500 mg, or 750 mg; once, twice, or three times a day
Claims 10–13: specific dose-frequency selections:
- Claim 10: 250 mg three times a day
- Claim 11: 500 mg three times a day
- Claim 12: 500 mg twice a day
- Claim 13: 750 mg once a day

Claim 14

mammal is “human”

Immediate technical read-across

These are classic “use/indication” and “method” claims around an antiviral in a neuropathic complication setting (PHN). The claim language narrows risk in two ways:

It is tied to PHN as the treated or prophylaxed condition (not generic “herpes zoster”).
It adds timing and dosing limitations through dependent claims, meaning infringement theories typically map to the exact label regimen or an evidence-backed regimen matching those limitations.

What is the real scope of protection: treatment vs prophylaxis, and what counts as PHN “treatment”?

Short answer: The patent covers both therapeutic treatment of PHN and prophylactic administration to prevent PHN in humans. The protection attaches to PHN management, not directly to the management of acute zoster pain unless the claimed method is framed and executed as PHN treatment/prophylaxis.

Infringement-relevant distinctions for enforcement

Therapeutic claims (Claim 1 and dependencies): execution requires administering famciclovir or penciclovir “for the treatment of PHN,” with dependent limitations (timing, age, dosing) where invoked.
Prophylaxis claims (Claim 15 and dependencies): execution requires administering an “effective prophylactic amount” to a human “in need” of prophylactic treatment of PHN.

What “in need of such treatment” tends to operationalize

Even without additional claim wording, these phrases typically track clinical determination that the patient has PHN (for treatment claims) or is at risk / needs prevention (for prophylaxis claims). From an enforcement lens, any contest usually turns on:

patient phenotype (PHN diagnosis vs non-PHN),
the physician’s intent and clinical reasoning (prophylaxis vs symptom management), and
the administered schedule.

How do the timing limits (72 hours, 48 hours) narrow infringement risk?

Short answer: Timing windows are key claim elements. Methods performed outside the “within 72 hours” (Claim 2) or “within 48 hours” (Claim 3) frames do not meet those dependent limitations.

Claim dependency and “gating” effect

Claim 1 is broad (no timing requirement).
Claim 2 and Claim 3 add timing limitations:
- ≤72 hours after rash onset (Claim 2)
- ≤48 hours after rash onset (Claim 3)

Practical enforcement implications

If litigation asserts infringement of Claims 2 or 3, the record must show administration relative to rash onset timing.
If a generic or competitor product is used with a different clinical timing standard, it may avoid dependent-claim infringement even if Claim 1 is still in play.

How does the 7-day treatment period limit matter for design-around?

Short answer: Claim 4 limits infringement for that dependent claim to “treatment period is 7 days,” which can create a pathway to avoid that dependent claim by varying treatment duration.

Claim interaction

Claim 4 depends on Claim 1. So a method matching Claim 4 must also meet Claim 1’s PHN-treatment elements.
A different duration (even if close, such as 5 or 10 days) breaks Claim 4’s specific “7 days” limitation.

What age thresholds are protected, and can competitors escape by treating other subgroups?

Short answer: The patent includes dependent claims for older age groups (>50, >60, >70). Methods outside those thresholds avoid those dependent claims.

Age-gated claim set

Claim 5: “greater than 50 years of age”
Claim 6: “greater than 60 years of age”
Claim 7: “greater than 70 years of age”

Design-around logic

Even if a physician treats PHN with famciclovir/penciclovir in younger populations, the older-age dependent claims are not met. However, the baseline Claim 1 and Claim 15 remain broader without age limitations.

Which famciclovir dose and frequency regimens are explicitly claimed?

Short answer: The patent explicitly claims multiple famciclovir dose-frequency configurations, plus a broader dose/frequency matrix.

Claim 9 matrix (breadth with controlled dimensions)

Claim 9 limits famciclovir dosing to:

Dose: 250 mg, 500 mg, or 750 mg
Frequency: once, twice, or three times a day

This is still fairly specific because it excludes other doses and other schedules (and it anchors on the named doses).

Explicit dependent dosing options

Claim 10: 250 mg three times a day
Claim 11: 500 mg three times a day
Claim 12: 500 mg twice a day
Claim 13: 750 mg once a day

Enforcement map

Infringement of Claims 10–13 typically turns on:

exact dose,
dosing frequency (e.g., BID vs TID vs QD),
confirmation that the drug was famciclovir (not another prodrug or alternative antiviral),
and PHN treatment/prophylaxis context.

Does the patent cover penciclovir dosing, or only famciclovir?

Short answer: The provided claim text explicitly lays out famciclovir dosing embodiments, while penciclovir appears in the baseline treatment and prophylaxis claims without the same dose-frequency detail.

Claim language implications

Claims 1 and 15 include “famciclovir or penciclovir… or pharmaceutically acceptable salt thereof.”
The detailed dose-frequency dependents (Claims 8–13 and 9–13) are scoped to famciclovir.
There is no parallel set of dependent penciclovir dose claims in the text provided (claims 8–13 are famciclovir-specific by their own dependency structure).

Result: Penciclovir exposure risk is higher for broader dependent coverage only where the baseline claims are asserted, and lower for specific dose-frequency attacks absent penciclovir-specific dependent claim limitations.

What is the US patent expiration and exclusivity outlook for 5,866,581?

Short answer: The patent’s lifespan in the US is governed by its patent term and any applicable adjustments/extensions, but those dates require the actual application/filing and patent-publication timeline. Without those bibliographic facts present here, a precise expiration date cannot be stated from the information provided.

What other US patents likely affect PHN methods with famciclovir/penciclovir?

Short answer: Without the underlying bibliographic record (application number, assignee, continuation set, and citing/related patents), a complete landscape cannot be enumerated. The claims you provided are method-of-use claims anchored to famciclovir/penciclovir for PHN with timing, age, and dosing limits, so the most relevant adjacent IP classes are:

other US method-of-use patents tied to antiviral treatment of post-herpetic complications,
patents claiming specific prophylaxis timing windows and duration,
patents covering formulations or dosing forms enabling the claimed regimen,
and any continuation patents with narrower or broader claim variants.

How strong is the patent estate for infringement cases: what would a Paragraph IV or non-infringement argument target?

Short answer: For method-of-use claims, typical defenses center on (i) absence of PHN indication evidence, (ii) absence of timely administration, and (iii) mismatch of dosing regimen and/or intended prophylaxis vs treatment.

Infringement elements most likely litigated

PHN diagnosis/endpoint
- Treatment claims require “PHN in mammals.”
- Prophylaxis claims require “prophylactic treatment of PHN in a human in need.”
Route and administration context
- The claims specify administration of an effective amount but do not list route in the text provided. Evidence will still focus on actual clinical use.
Timing
- Dependent limitations in Claims 2 and 3 create discrete thresholds tied to rash onset.
Dosing regimen
- Dependent limitations in Claims 9–13 require exact dose-frequency patterns.
Age
- Dependent limitations Claims 5–7 narrow to older cohorts.

Claim construction pressure points

“within 72 hours of rash onset” and “within 48 hours of rash onset” are likely to be construed around factual ascertainment of rash onset.
“treatment period is 7 days” is discrete and can be a clean mismatch target.
“effective prophylactic amount” is factual and evidence-driven but still anchored to a claimed prophylaxis purpose.

What is the most likely “generic entry” or competitive risk pattern?

Short answer: A generic of famciclovir or penciclovir typically does not face product-claim exclusivity barriers for method-of-use patents unless the generic product is launched with label or promotional use that aligns with the patented method. The key issue is alignment between real-world prescribing practices and the patented method constraints (PHN indication, prophylaxis framing, timing, dosing regimen, and patient cohort).

Real-world launch risk drivers

Label carve-outs: If the generic’s labeling does not support PHN prophylaxis/treatment in the claimed timing/dose framework, that reduces alignment with method claims.
Off-label promotion vs actual prescribing: US method-of-use infringement can depend on evidence that the method was practiced, not merely that the drug could be used.
Physician practice patterns: Even without label alignment, if patients are treated in ways matching the claims, risk persists.

How does 5,866,581 compare with other method-of-use antivirals in PHN?

Short answer: Compared with broader PHN prevention method patents, this one is unusually claim-dense on operational variables: early treatment windows, a specific treatment period (7 days), age thresholds, and enumerated famciclovir dose-frequency options. That structure can both (i) narrow the infringement target and (ii) strengthen enforcement where clinical evidence matches the specific regimen.

Relative positioning

More specific than patents that cover “antiviral for PHN” without timing/dose constraints.
Less likely to be avoided entirely by schedule changes because Claim 1 still exists without timing or dosing limits; however, dependent claims can be avoided by varying timing/duration/dose.

Key Takeaways

US Patent 5,866,581 covers method-of-treatment and method-of-prophylaxis for post-herpetic neuralgia (PHN) using famciclovir or penciclovir.
The most enforceable claim hooks are the timing windows (≤72 hours and ≤48 hours after rash onset), the treatment duration (7 days), age thresholds (>50, >60, >70), and enumerated famciclovir dose-frequency regimens (250 mg TID; 500 mg TID; 500 mg BID; 750 mg QD).
Baseline coverage (Claims 1 and 15) is broad enough that design-around often requires evidence-based changes in how the drug is actually used to manage PHN (not just substitution of the active ingredient).
Penciclovir appears in baseline claims, while the detailed dosing dependents are famciclovir-specific in the provided claim set.

FAQs

1) Does US 5,866,581 require treatment within 72 hours of rash onset?
No. “within 72 hours” is a dependent limitation (Claim 2). Claim 1 does not require a timing window.

2) Can a competitor avoid infringement of the 7-day limitation?
Yes for Claim 4 specifically. The “7 days” duration is a dependent claim; a different treatment period breaks Claim 4 while other claims may still be asserted.

3) Are famciclovir dosing regimens the same for prophylaxis claims as treatment claims?
The claim set provided mirrors famciclovir dose dependents under the prophylaxis umbrella (Claim 15 → Claims 16–18). The dosing limitation structure aligns to the same famciclovir dose-frequency options stated.

4) Is age >70 a strict requirement for any infringement risk?
No. Age thresholds (>50, >60, >70) are dependent claims. Methods outside those age bands avoid those dependent claims but may still implicate broader claims without age limits.

5) Does the patent cover prophylactic treatment only for humans?
Yes. Claim 15 expressly limits prophylactic treatment to “a human in need of such treatment.”

References (APA)

US Patent 5,866,581. (n.d.). Method for treatment and prophylaxis of post-herpetic neuralgia using famciclovir or penciclovir.

Title:	Penciclovir for the treatment of post therapeutic neuralgia
Abstract:	A method for the treatment of PHN in mammals, including humans, which method comprises administering an effective amount of a compound of formula (A), or a pharmaceutically acceptable salt thereof. ##STR1##
Inventor(s):	Ronald James Boon, David Ronald John Griffin
Assignee:	Novartis Pharmaceuticals Corp
Application Number:	US08/624,466
Patent Claim Types: see list of patent claims	Use;
Patent landscape, scope, and claims:	Scope and Patent Landscape for US Patent 5,866,581 (Famciclovir/Penciclovir for Post-Herpetic Neuralgia, US Claims 1–21) US Patent 5,866,581 covers specific therapeutic and prophylactic uses of famciclovir or penciclovir for post-herpetic neuralgia (PHN), including treatment timing windows after rash onset, duration (7 days), and treatment in older age strata. The claims are directed to method-of-treatment and method-of-prophylaxis with particular dosing regimens (including famciclovir 250 mg/500 mg/750 mg and multiple daily frequency options). From a freedom-to-operate and litigation-risk perspective, the most infringement-relevant claim elements are: (i) PHN indication, (ii) drug identity (famciclovir or penciclovir), (iii) timing relative to rash onset (≤72 hours, ≤48 hours), and (iv) specified dosing/frequency combinations for famciclovir. What is US Patent 5,866,581 and what PHN uses does it claim? Short answer: The patent claims methods for treating PHN in mammals (including humans) using famciclovir or penciclovir, and prophylactic treatment methods in humans, with additional limitations for early treatment timing, treatment duration, patient age, and specific famciclovir dosing regimens. Core claim structure (independent and dependent claims) Claim 1 (treatment method, broad baseline) “A method for the treatment of PHN in mammals… administering an effective amount of famciclovir or penciclovir… or pharmaceutically acceptable salt.” Claim 15 (prophylactic method, baseline) “A method for prophylactic treatment of PHN in a human… administering an effective prophylactic amount of famciclovir or penciclovir…” Claims 2–4 (timing and duration) Claim 2: treatment “within 72 hours of rash onset” Claim 3: treatment “within 48 hours of rash onset” Claim 4: treatment period “7 days” Claims 5–7 (age-limited subgroups) Claim 5: patients “greater than 50 years” Claim 6: “greater than 60 years” Claim 7: “greater than 70 years” Claims 8–14 (famciclovir-specific dosing configurations) Claim 8: compound is famciclovir Claim 9: famciclovir at 250 mg, 500 mg, or 750 mg; once, twice, or three times a day Claims 10–13: specific dose-frequency selections: Claim 10: 250 mg three times a day Claim 11: 500 mg three times a day Claim 12: 500 mg twice a day Claim 13: 750 mg once a day Claim 14 mammal is “human” Immediate technical read-across These are classic “use/indication” and “method” claims around an antiviral in a neuropathic complication setting (PHN). The claim language narrows risk in two ways: It is tied to PHN as the treated or prophylaxed condition (not generic “herpes zoster”). It adds timing and dosing limitations through dependent claims, meaning infringement theories typically map to the exact label regimen or an evidence-backed regimen matching those limitations. What is the real scope of protection: treatment vs prophylaxis, and what counts as PHN “treatment”? Short answer: The patent covers both therapeutic treatment of PHN and prophylactic administration to prevent PHN in humans. The protection attaches to PHN management, not directly to the management of acute zoster pain unless the claimed method is framed and executed as PHN treatment/prophylaxis. Infringement-relevant distinctions for enforcement Therapeutic claims (Claim 1 and dependencies): execution requires administering famciclovir or penciclovir “for the treatment of PHN,” with dependent limitations (timing, age, dosing) where invoked. Prophylaxis claims (Claim 15 and dependencies): execution requires administering an “effective prophylactic amount” to a human “in need” of prophylactic treatment of PHN. What “in need of such treatment” tends to operationalize Even without additional claim wording, these phrases typically track clinical determination that the patient has PHN (for treatment claims) or is at risk / needs prevention (for prophylaxis claims). From an enforcement lens, any contest usually turns on: patient phenotype (PHN diagnosis vs non-PHN), the physician’s intent and clinical reasoning (prophylaxis vs symptom management), and the administered schedule. How do the timing limits (72 hours, 48 hours) narrow infringement risk? Short answer: Timing windows are key claim elements. Methods performed outside the “within 72 hours” (Claim 2) or “within 48 hours” (Claim 3) frames do not meet those dependent limitations. Claim dependency and “gating” effect Claim 1 is broad (no timing requirement). Claim 2 and Claim 3 add timing limitations: ≤72 hours after rash onset (Claim 2) ≤48 hours after rash onset (Claim 3) Practical enforcement implications If litigation asserts infringement of Claims 2 or 3, the record must show administration relative to rash onset timing. If a generic or competitor product is used with a different clinical timing standard, it may avoid dependent-claim infringement even if Claim 1 is still in play. How does the 7-day treatment period limit matter for design-around? Short answer: Claim 4 limits infringement for that dependent claim to “treatment period is 7 days,” which can create a pathway to avoid that dependent claim by varying treatment duration. Claim interaction Claim 4 depends on Claim 1. So a method matching Claim 4 must also meet Claim 1’s PHN-treatment elements. A different duration (even if close, such as 5 or 10 days) breaks Claim 4’s specific “7 days” limitation. What age thresholds are protected, and can competitors escape by treating other subgroups? Short answer: The patent includes dependent claims for older age groups (>50, >60, >70). Methods outside those thresholds avoid those dependent claims. Age-gated claim set Claim 5: “greater than 50 years of age” Claim 6: “greater than 60 years of age” Claim 7: “greater than 70 years of age” Design-around logic Even if a physician treats PHN with famciclovir/penciclovir in younger populations, the older-age dependent claims are not met. However, the baseline Claim 1 and Claim 15 remain broader without age limitations. Which famciclovir dose and frequency regimens are explicitly claimed? Short answer: The patent explicitly claims multiple famciclovir dose-frequency configurations, plus a broader dose/frequency matrix. Claim 9 matrix (breadth with controlled dimensions) Claim 9 limits famciclovir dosing to: Dose: 250 mg, 500 mg, or 750 mg Frequency: once, twice, or three times a day This is still fairly specific because it excludes other doses and other schedules (and it anchors on the named doses). Explicit dependent dosing options Claim 10: 250 mg three times a day Claim 11: 500 mg three times a day Claim 12: 500 mg twice a day Claim 13: 750 mg once a day Enforcement map Infringement of Claims 10–13 typically turns on: exact dose, dosing frequency (e.g., BID vs TID vs QD), confirmation that the drug was famciclovir (not another prodrug or alternative antiviral), and PHN treatment/prophylaxis context. Does the patent cover penciclovir dosing, or only famciclovir? Short answer: The provided claim text explicitly lays out famciclovir dosing embodiments, while penciclovir appears in the baseline treatment and prophylaxis claims without the same dose-frequency detail. Claim language implications Claims 1 and 15 include “famciclovir or penciclovir… or pharmaceutically acceptable salt thereof.” The detailed dose-frequency dependents (Claims 8–13 and 9–13) are scoped to famciclovir. There is no parallel set of dependent penciclovir dose claims in the text provided (claims 8–13 are famciclovir-specific by their own dependency structure). Result: Penciclovir exposure risk is higher for broader dependent coverage only where the baseline claims are asserted, and lower for specific dose-frequency attacks absent penciclovir-specific dependent claim limitations. What is the US patent expiration and exclusivity outlook for 5,866,581? Short answer: The patent’s lifespan in the US is governed by its patent term and any applicable adjustments/extensions, but those dates require the actual application/filing and patent-publication timeline. Without those bibliographic facts present here, a precise expiration date cannot be stated from the information provided. What other US patents likely affect PHN methods with famciclovir/penciclovir? Short answer: Without the underlying bibliographic record (application number, assignee, continuation set, and citing/related patents), a complete landscape cannot be enumerated. The claims you provided are method-of-use claims anchored to famciclovir/penciclovir for PHN with timing, age, and dosing limits, so the most relevant adjacent IP classes are: other US method-of-use patents tied to antiviral treatment of post-herpetic complications, patents claiming specific prophylaxis timing windows and duration, patents covering formulations or dosing forms enabling the claimed regimen, and any continuation patents with narrower or broader claim variants. How strong is the patent estate for infringement cases: what would a Paragraph IV or non-infringement argument target? Short answer: For method-of-use claims, typical defenses center on (i) absence of PHN indication evidence, (ii) absence of timely administration, and (iii) mismatch of dosing regimen and/or intended prophylaxis vs treatment. Infringement elements most likely litigated PHN diagnosis/endpoint Treatment claims require “PHN in mammals.” Prophylaxis claims require “prophylactic treatment of PHN in a human in need.” Route and administration context The claims specify administration of an effective amount but do not list route in the text provided. Evidence will still focus on actual clinical use. Timing Dependent limitations in Claims 2 and 3 create discrete thresholds tied to rash onset. Dosing regimen Dependent limitations in Claims 9–13 require exact dose-frequency patterns. Age Dependent limitations Claims 5–7 narrow to older cohorts. Claim construction pressure points “within 72 hours of rash onset” and “within 48 hours of rash onset” are likely to be construed around factual ascertainment of rash onset. “treatment period is 7 days” is discrete and can be a clean mismatch target. “effective prophylactic amount” is factual and evidence-driven but still anchored to a claimed prophylaxis purpose. What is the most likely “generic entry” or competitive risk pattern? Short answer: A generic of famciclovir or penciclovir typically does not face product-claim exclusivity barriers for method-of-use patents unless the generic product is launched with label or promotional use that aligns with the patented method. The key issue is alignment between real-world prescribing practices and the patented method constraints (PHN indication, prophylaxis framing, timing, dosing regimen, and patient cohort). Real-world launch risk drivers Label carve-outs: If the generic’s labeling does not support PHN prophylaxis/treatment in the claimed timing/dose framework, that reduces alignment with method claims. Off-label promotion vs actual prescribing: US method-of-use infringement can depend on evidence that the method was practiced, not merely that the drug could be used. Physician practice patterns: Even without label alignment, if patients are treated in ways matching the claims, risk persists. How does 5,866,581 compare with other method-of-use antivirals in PHN? Short answer: Compared with broader PHN prevention method patents, this one is unusually claim-dense on operational variables: early treatment windows, a specific treatment period (7 days), age thresholds, and enumerated famciclovir dose-frequency options. That structure can both (i) narrow the infringement target and (ii) strengthen enforcement where clinical evidence matches the specific regimen. Relative positioning More specific than patents that cover “antiviral for PHN” without timing/dose constraints. Less likely to be avoided entirely by schedule changes because Claim 1 still exists without timing or dosing limits; however, dependent claims can be avoided by varying timing/duration/dose. Key Takeaways US Patent 5,866,581 covers method-of-treatment and method-of-prophylaxis for post-herpetic neuralgia (PHN) using famciclovir or penciclovir. The most enforceable claim hooks are the timing windows (≤72 hours and ≤48 hours after rash onset), the treatment duration (7 days), age thresholds (>50, >60, >70), and enumerated famciclovir dose-frequency regimens (250 mg TID; 500 mg TID; 500 mg BID; 750 mg QD). Baseline coverage (Claims 1 and 15) is broad enough that design-around often requires evidence-based changes in how the drug is actually used to manage PHN (not just substitution of the active ingredient). Penciclovir appears in baseline claims, while the detailed dosing dependents are famciclovir-specific in the provided claim set. FAQs 1) Does US 5,866,581 require treatment within 72 hours of rash onset? No. “within 72 hours” is a dependent limitation (Claim 2). Claim 1 does not require a timing window. 2) Can a competitor avoid infringement of the 7-day limitation? Yes for Claim 4 specifically. The “7 days” duration is a dependent claim; a different treatment period breaks Claim 4 while other claims may still be asserted. 3) Are famciclovir dosing regimens the same for prophylaxis claims as treatment claims? The claim set provided mirrors famciclovir dose dependents under the prophylaxis umbrella (Claim 15 → Claims 16–18). The dosing limitation structure aligns to the same famciclovir dose-frequency options stated. 4) Is age >70 a strict requirement for any infringement risk? No. Age thresholds (>50, >60, >70) are dependent claims. Methods outside those age bands avoid those dependent claims but may still implicate broader claims without age limits. 5) Does the patent cover prophylactic treatment only for humans? Yes. Claim 15 expressly limits prophylactic treatment to “a human in need of such treatment.” References (APA) US Patent 5,866,581. (n.d.). Method for treatment and prophylaxis of post-herpetic neuralgia using famciclovir or penciclovir. More… ↓ ⤷ Start Trial

Foriegn Application Priority Data
Foreign Country	Foreign Patent Number	Foreign Patent Date
United Kingdom	9320485	Oct 05, 1993
United Kingdom	9321255	Oct 14, 1993

PCT Information
PCT Filed	October 04, 1994	PCT Application Number:	PCT/GB94/02156
PCT Publication Date:	April 13, 1995	PCT Publication Number:	WO95/09632

Country	Patent Number	Estimated Expiration	Supplementary Protection Certificate	SPC Country	SPC Expiration
African Regional IP Organization (ARIPO)	616	⤷ Start Trial
African Regional IP Organization (ARIPO)	9400684	⤷ Start Trial
Austria	216885	⤷ Start Trial
Australia	1383495	⤷ Start Trial
>Country	>Patent Number	>Estimated Expiration	>Supplementary Protection Certificate	>SPC Country	>SPC Expiration

Details for Patent: 5,866,581

Summary for Patent: 5,866,581