Details for Patent: 8,900,566

Which drugs does patent 8,900,566 protect, and when does it expire?

Patent 8,900,566 protects DAKLINZA and is included in one NDA.

This patent has sixty-eight patent family members in thirty-one countries.

Summary for Patent: 8,900,566

Title:	Hepatitis C virus inhibitors
Abstract:	The present disclosure relates to compounds, compositions and methods for the treatment of hepatitis C virus (HCV) infection. Also disclosed are pharmaceutical compositions containing such compounds and methods for using these compounds in the treatment of HCV infection.
Inventor(s):	Makonen Belema, Van N. Nguyen
Assignee:	Bristol Myers Squibb Co
Application Number:	US14/030,199
Patent Claim Types: see list of patent claims	Use;

US Patent 8,900,566: Daclatasvir HCV Method-of-Use Claims and Patent Landscape

US Patent 8,900,566 covers methods of treating or reducing hepatitis C virus infection with daclatasvir, also known as BMS-790052, or a pharmaceutically acceptable salt. The patent does not claim daclatasvir as a chemical compound, its composition, or a manufacturing process. Its operative scope is treatment-method protection, including combination therapy with interferon, ribavirin and other anti-HCV agents.

The claims are narrow as to the active molecule but broad as to treatment combinations and biological targets. The patent is relevant to historical generic-entry analysis for Daklinza, but it is not a biosimilar patent and does not independently block manufacture of daclatasvir outside the claimed therapeutic use.

What drug does US Patent 8,900,566 protect?

The claimed compound is daclatasvir, a first-in-class HCV NS5A inhibitor developed by Bristol-Myers Squibb.

Item	Data
Active ingredient	Daclatasvir
Development code	BMS-790052
Brand	Daklinza
Drug class	HCV NS5A replication-complex inhibitor
FDA approval	July 24, 2015
Original NDA	NDA 205834
Approved use	In combination with other agents for chronic HCV infection
Patent at issue	US 8,900,566
Patent type	Method of treatment
Primary assignee	Bristol-Myers Squibb-related patent ownership
Claimed dosage form	No specific dosage form required
Claimed salt coverage	Yes
Biosimilar framework	Not applicable; daclatasvir is a small molecule

Daclatasvir inhibits the HCV NS5A protein, which is required for viral RNA replication and assembly. The patent claims identify the molecule through its full chemical name rather than by the shorter name “daclatasvir.” The structural identity corresponds to daclatasvir, including its paired imidazole-biphenyl architecture, pyrrolidine groups and carbamate-substituted valine residues.[1][2]

What are the independent and dependent claims?

Claim 1 is the only independent claim. It requires four elements:

1. A patient has an HCV infection.
2. Daclatasvir, or a pharmaceutically acceptable salt, is administered.
3. The amount administered is therapeutically effective.
4. The administration inhibits or relieves the HCV infection.

The claim does not require:

• A specific HCV genotype.
• A specified dose.
• A defined treatment duration.
• A particular route of administration.
• A particular formulation.
• Co-administration with another antiviral.
• A specific viral-load endpoint.

The claim is therefore molecule-specific but clinically broad.

Claims 2 through 7 depend on claim 1 and add combination-treatment limitations.

Claim	Additional limitation	Practical scope
1	Daclatasvir treatment	Core monotherapy or treatment-use claim
2	One or two additional anti-HCV compounds	Combination therapy
3	Interferon or ribavirin	Conventional interferon/ribavirin combinations
4	Specified interferon types	Peginterferon and related interferon regimens
5	Immunomodulators, RNA agents, ribavirin, IMPDH inhibitors and related agents	Broad historical combination category
6	Agent targeting HCV protease, polymerase, NS4B, entry, assembly, egress, NS5A or IMPDH	Mechanism-defined combination claim
7	Agent targeting HCV serine protease or polymerase	Direct-acting antiviral combinations

How broad is claim 1?

Claim 1 is chemically narrow and therapeutically broad.

A product or regimen would need to involve the specific daclatasvir molecule or a pharmaceutically acceptable salt. A structurally different NS5A inhibitor would not literally satisfy the molecule limitation. The claim does not cover the entire NS5A inhibitor class.

The treatment language is broader. “Inhibiting and/or relieving” HCV infection can cover antiviral treatment intended to reduce viral replication, viral load or disease manifestations. The phrase “therapeutically effective amount” is functional and does not impose a numerical dosing threshold in the claim.

The absence of a genotype limitation increases the potential reach across HCV genotypes, subject to the approved label and the technical disclosure supporting the relevant genotype coverage. The absence of a route, formulation or dosing limitation also means that the claim is not confined to tablets, once-daily administration or any particular pharmaceutical excipient system.

What combination therapies are protected?

Claims 2 through 7 create a layered combination-therapy estate.

Interferon and ribavirin combinations

Claims 2 and 3 cover daclatasvir administered with interferon or ribavirin. Claim 4 identifies interferon alpha-2B, pegylated interferon alpha, consensus interferon, interferon alpha-2A and lymphoblastoid interferon tau.

These claims reflect the treatment environment during daclatasvir’s development, when pegylated interferon and ribavirin were central components of HCV therapy. Their commercial importance declined after the introduction of all-oral direct-acting antiviral regimens.

Direct-acting antiviral combinations

Claim 6 covers a second anti-HCV agent by reference to its biological target. Claim 7 narrows the target to HCV serine protease or HCV polymerase.

This language can reach combinations involving:

• HCV NS3/4A protease inhibitors.
• HCV NS5B polymerase inhibitors.
• Certain NS5A inhibitors.
• Agents directed to NS4B, entry, assembly or egress.
• IMPDH inhibitors.

The claim is not limited to named compounds. A combination partner can fall within the claim if it performs the specified inhibitory function and is used for HCV treatment.

This creates potential overlap with combination products and co-packaged regimens involving daclatasvir and other direct-acting antivirals. The claim does not require that the two agents be physically combined into one dosage form. “Prior to, after or simultaneously with” covers sequential and concurrent administration.

Does US 8,900,566 protect a formulation or manufacturing process?

No. The issued claims provided are method claims.

They do not expressly claim:

• A daclatasvir tablet.
• A solid dispersion.
• A specific polymorph.
• A salt-selection process.
• A crystalline form.
• A formulation excipient.
• A manufacturing intermediate.
• A chemical synthesis route.
• A process for preparing daclatasvir.
• Packaging or dosage-form technology.

A generic manufacturer could therefore face different infringement questions depending on its product and label. If the generic product contains daclatasvir but its labeling omits the patented treatment use, a direct product claim would not arise from this patent because the patent does not contain a composition claim. If the labeling instructs use in a manner covered by claim 1 or the dependent combination claims, induced-infringement risk becomes more significant under 35 U.S.C. §271(b).[3]

When does US Patent 8,900,566 lose exclusivity?

A US utility patent generally expires 20 years from the earliest effective nonprovisional filing date, subject to patent-term adjustment, patent-term extension and terminal disclaimers.[4]

The relevant patent-family dates and term calculations must be read from the issued patent, its continuity data and the USPTO Patent Center record. The grant date, November 25, 2014, does not determine the expiration date. The patent may have an expiration date materially later than 20 years after the international or provisional priority date if the US nonprovisional filing occurred later, or materially different treatment if terminal disclaimers or patent-term adjustments apply.

Exclusivity issue	Effect on US 8,900,566
Patent term	Controlled by the effective US nonprovisional filing date
Patent-term adjustment	May extend the ordinary 20-year term
Patent-term extension under 35 U.S.C. §156	Potentially relevant to an approved drug, but must be confirmed for this patent
Regulatory exclusivity	Separate from patent term
Pediatric exclusivity	Adds six months only if granted for the relevant NDA
Patent grant date	Does not establish expiration
Claim type	Method of use, not composition

The FDA’s Orange Book must be checked against the relevant NDA and current patent-listing data to determine whether the patent was listed and whether a listed expiration date remained current.[5]

What is the FDA and Orange Book status of Daklinza?

Daklinza was approved by the FDA in 2015 in combination with sofosbuvir for chronic HCV infection. The approval reflected the transition from interferon-based treatment to all-oral direct-acting antiviral therapy.[2]

FDA regulatory status and patent status are separate:

• FDA approval authorizes the labeled drug and indications.
• Orange Book listing identifies patents submitted by the NDA holder as relevant to approved drug products.
• A listed method-of-use patent may require a generic applicant to make a Paragraph IV certification or a section viii statement, depending on the patent listing and the proposed labeling.
• FDA approval does not itself determine whether a patent is valid or infringed.

Daklinza’s declining US commercial availability and the evolution of HCV treatment reduce the practical value of some historical method-of-use claims. The patent remains legally relevant if a proposed generic label directs use covered by the claims, but the commercial consequences depend heavily on whether the product has an active US market and whether alternative labels can omit the protected indication.

Which companies challenged daclatasvir exclusivity?

The provided patent and claims do not establish a Paragraph IV filing, ANDA applicant, district-court action or settlement agreement. Those facts cannot be inferred from the patent text.

For US 8,900,566, a complete challenge analysis requires matching:

1. FDA Orange Book patent listings for NDA 205834.
2. ANDA Paragraph IV notices.
3. District-court complaints under 35 U.S.C. §271(e)(2).
4. Federal Circuit appeals.
5. FDA approval dates for any ANDA.
6. Settlement or license terms.

The patent number alone does not prove that a Paragraph IV challenge occurred. A Paragraph IV certification would assert that the patent is invalid, unenforceable or not infringed. It would not automatically invalidate the patent or permit immediate launch.

What patent litigation affects daclatasvir?

The supplied information identifies no litigation involving US 8,900,566. The patent’s litigation posture should therefore be classified as unconfirmed rather than treated as litigated or unlitigated.

Potential litigation theories would include:

• Noninfringement based on a label that omits daclatasvir use covered by claim 1.
• Noninfringement based on omission of combination instructions.
• Invalidity for anticipation or obviousness.
• Written-description or enablement challenges to broad target-based combination claims.
• Indefiniteness challenges to “therapeutically effective amount” or functional target language.
• Exhaustion or authorized-sale defenses for specific product transactions.
• Induced infringement based on prescribing, promotional or labeling instructions.

Claim 1 presents a stronger enforcement profile against a label expressly directing daclatasvir treatment for HCV. Claims 6 and 7 are more fact-dependent because they require analysis of the combination partner’s biological target and the actual directions for use.

How strong is the patent estate?

US 8,900,566 is best characterized as a secondary or companion patent within the daclatasvir estate, not the principal chemical-compound patent.

Strength factor	Assessment
Chemical specificity	Strong against daclatasvir-specific use; weak against other NS5A inhibitors
Treatment breadth	Broad because dose, route and genotype are not specified
Combination coverage	Broad, but dependent on the second agent and its labeled use
Formulation protection	None in the quoted claims
Manufacturing protection	None in the quoted claims
Biosimilar relevance	None
Generic-label leverage	Potentially meaningful if the label includes covered HCV uses
Vulnerability	Functional language and broad combination categories may invite validity and scope disputes
Commercial value	Dependent on continued US daclatasvir sales and the presence of an approved generic market

The most important distinction is between compound entry and labeled-use entry. A manufacturer may be able to develop or source daclatasvir without infringing a method claim, while still facing induced-infringement exposure if its proposed labeling, promotional materials or distribution conduct encourage the claimed treatment.

How does this patent compare with competing HCV patent estates?

Daclatasvir’s patent estate differs from estates for sofosbuvir, ledipasvir, elbasvir, grazoprevir and glecaprevir/pibrentasvir.

Drug	Primary target	Patent risk profile
Daclatasvir	NS5A	Compound, formulation and method claims across BMS families
Sofosbuvir	NS5B polymerase	Strong compound and prodrug-related estate associated with Gilead
Ledipasvir	NS5A	Compound and combination patents associated with Gilead
Elbasvir	NS5A	Merck compound and regimen estate
Grazoprevir	NS3/4A protease	Merck compound and combination estate
Glecaprevir/pibrentasvir	NS3/4A and NS5A	AbbVie combination and component estates

Daclatasvir was frequently used in combinations with sofosbuvir. A commercial launch could therefore require analysis of both daclatasvir method patents and any surviving patents covering the companion antiviral, particularly where the proposed label reproduces a branded regimen.

What generic-entry risks exist?

The principal generic-entry scenarios are:

Label-preserving launch

A generic applicant proposes the same HCV indication and regimen instructions as Daklinza. This creates the highest risk under claim 1 and, where applicable, claims 2 through 7. A Paragraph IV certification would likely be required for any listed patent that covers the proposed use.

Skinny-label launch

The applicant removes a patented indication or combination instruction while retaining unpatented uses. The effectiveness of this strategy depends on the Orange Book use code, the final label and evidence of induced infringement. A skinny label does not eliminate all risk if the remaining label still encourages the patented use.

Post-expiration launch

The applicant waits until patent and regulatory exclusivities expire. This minimizes litigation exposure but sacrifices early-entry value.

Off-label or restricted distribution

A manufacturer may argue that the approved label does not direct the patented use, while plaintiffs may rely on marketing, sales activity or physician-facing materials. This is highly fact-specific.

Daclatasvir is a small molecule, so the relevant abbreviated pathway is an ANDA under section 505(j), not a biosimilar application under section 351(k). The Purple Book is not the primary source for daclatasvir exclusivity.[5][6]

What revenue exposure is linked to US 8,900,566?

The patent’s revenue exposure is lower than that of a composition-of-matter patent because it does not independently prevent all sales of daclatasvir-containing products. Its value depends on whether the patent can constrain the approved or commercially attractive treatment indication.

Revenue exposure is affected by:

• The size of the remaining US HCV treatment market.
• The availability of pan-genotypic alternatives.
• Whether Daklinza remains actively marketed.
• Whether daclatasvir is sold as a standalone product or in a regimen.
• The enforceability of the listed use code.
• The presence of other unexpired BMS patents.
• The ability of a generic applicant to omit protected indications.

For investment or licensing analysis, US 8,900,566 should not be valued as a standalone barrier equivalent to a valid, unexpired composition patent.

Key Takeaways

• US 8,900,566 covers methods of treating HCV with daclatasvir or its pharmaceutically acceptable salts.
• Claim 1 is narrow to the specific molecule but broad regarding patient population, dosage, route and treatment duration.
• Claims 2 through 7 cover combinations with interferon, ribavirin and target-defined anti-HCV agents.
• The quoted claims do not protect daclatasvir composition, formulation, polymorph, synthesis or manufacturing.
• The patent is relevant to ANDA label analysis and possible induced-infringement disputes.
• Daclatasvir is a small molecule, so biosimilar analysis does not apply.
• The patent’s precise expiration date requires the USPTO term record and any FDA patent-term-extension data.
• The supplied record does not establish a Paragraph IV challenge, litigation action or settlement involving this patent.
• Commercial value depends on the current Daklinza market, Orange Book listing status and the strength of the broader BMS daclatasvir estate.

FAQs

Is US 8,900,566 a composition-of-matter patent for daclatasvir?

No. The quoted claims are method-of-treatment claims. They require administering daclatasvir for HCV treatment but do not claim the compound as a standalone composition.

Can a generic company sell daclatasvir without infringing this patent?

Potentially, depending on the proposed label, marketing conduct and other patents. The patent does not contain a product claim, but a label directing a use covered by claim 1 may create induced-infringement risk.

Does US 8,900,566 cover sofosbuvir by itself?

No. The patent does not claim sofosbuvir as a compound. Claim 6 or claim 7 could become relevant to a daclatasvir-sofosbuvir regimen if the combination and use satisfy the claim limitations.

Are daclatasvir products subject to biosimilar approval?

No. Daclatasvir is a chemically synthesized small molecule. Generic versions proceed through the ANDA pathway rather than the biosimilar pathway.

Does the patent cover all NS5A inhibitors?

No. Claim 1 is limited to daclatasvir or a pharmaceutically acceptable salt. The dependent claims may cover combination use with an agent acting on NS5A, but they do not claim every NS5A inhibitor as a standalone product.

References

1. United States Patent No. 8,900,566. (2014). Methods of treating HCV infection. United States Patent and Trademark Office.
2. U.S. Food and Drug Administration. (2015). Daklinza (daclatasvir) prescribing information.
3. 35 U.S.C. § 271. (2024). Infringement of patent.
4. 35 U.S.C. § 154. (2024). Contents and term of patent; provisional rights.
5. U.S. Food and Drug Administration. (2024). Approved drug products with therapeutic equivalence evaluations: Orange Book.
6. U.S. Food and Drug Administration. (2024). Purple Book: Database of licensed biological products.

Drugs Protected by US Patent 8,900,566

Applicant	Tradename	Generic Name	Dosage	NDA	Approval Date	TE	Type	RLD	RS	Patent No.	Patent Expiration	Product	Substance	Delist Req.	Patented / Exclusive Use	Submissiondate
Bristol-myers Squibb	DAKLINZA	daclatasvir dihydrochloride	TABLET;ORAL	206843-001	Jul 24, 2015		DISCN	Yes	No	8,900,566					METHOD OF INHIBITING HEPATITIS C VIRUS WITH DAKLINZA AND AT LEAST ONE ADDITIONAL COMPOUND HAVING ANTI-HCV ACTIVITY
Bristol-myers Squibb	DAKLINZA	daclatasvir dihydrochloride	TABLET;ORAL	206843-001	Jul 24, 2015		DISCN	Yes	No	8,900,566					METHOD OF INHIBITING HEPATITIS C VIRUS
Bristol-myers Squibb	DAKLINZA	daclatasvir dihydrochloride	TABLET;ORAL	206843-002	Jul 24, 2015		DISCN	Yes	No	8,900,566					METHOD OF INHIBITING HEPATITIS C VIRUS WITH DAKLINZA AND AT LEAST ONE ADDITIONAL COMPOUND HAVING ANTI-HCV ACTIVITY
Bristol-myers Squibb	DAKLINZA	daclatasvir dihydrochloride	TABLET;ORAL	206843-002	Jul 24, 2015		DISCN	Yes	No	8,900,566					METHOD OF INHIBITING HEPATITIS C VIRUS

International Family Members for US Patent 8,900,566

Country	Patent Number	Estimated Expiration	Supplementary Protection Certificate	SPC Country	SPC Expiration
European Patent Office	2049522		C300713	Netherlands
European Patent Office	2049522		CA 2015 00003	Denmark
European Patent Office	2049522		C20150003 00128	Estonia
European Patent Office	2049522		PA2015006	Lithuania