United States Patent 7,399,787: Vorinostat Patent Scope, Claim Analysis, Expiration, and Patent Landscape

United States Patent 7,399,787 covers oral treatment of cutaneous T-cell lymphoma (CTCL) with suberoylanilide hydroxamic acid, commonly known as vorinostat or SAHA, at two defined dosing regimens. The principal independent claims cover either 400 mg once daily or 300 mg twice daily for two weeks followed by one week without treatment. The patent also claims capsule dosage forms containing conventional excipients.

The patent issued July 15, 2008, and its statutory patent term ended January 28, 2022, based on the underlying nonprovisional filing date. It is therefore expired and no longer creates an enforceable U.S. patent barrier to generic vorinostat treatment or formulation practices falling within the claims. The patent was historically important because it covered the clinical CTCL dosing regimens used for Zolinza, but it was not the basic compound patent for vorinostat.

What drug does U.S. Patent 7,399,787 protect?

U.S. Patent 7,399,787 protects methods using suberoylanilide hydroxamic acid, or SAHA. SAHA is the active pharmaceutical ingredient in Zolinza, marketed by Merck for CTCL.

Attribute	Information
Patent	U.S. Patent 7,399,787
Title	Methods of treating cutaneous T-cell lymphoma
Active ingredient	Suberoylanilide hydroxamic acid, SAHA
Generic name	Vorinostat
Brand	Zolinza
Therapeutic category	Histone deacetylase inhibitor
Covered disease	Cutaneous T-cell lymphoma
Issue date	July 15, 2008
Statutory term end	January 28, 2022
Current status	Expired
Primary commercial sponsor	Merck, following acquisition of Aton Pharma
Historical patent owner/licensing chain	Columbia University-related patent ownership and commercial licensing interests

The patent is a method-of-treatment patent. It does not broadly claim every use of vorinostat, every vorinostat composition, or every histone deacetylase inhibitor. Its enforceable scope was tied to the claimed CTCL indication, oral administration, pharmaceutical composition, and specified dose schedule.[1]

What are the independent claims of Patent 7,399,787?

Claims 1 and 6 are the principal independent claims. Claim 11 operates as a narrower independent-style claim dependent on either claim 1 or claim 6.

Claim	Core subject matter	Dose and schedule
1	Oral treatment of CTCL with SAHA or a pharmaceutically acceptable salt or hydrate in a pharmaceutical composition	400 mg once daily
6	Oral treatment of CTCL with SAHA or a pharmaceutically acceptable salt or hydrate in a pharmaceutical composition	300 mg twice daily for two weeks, then one week off
11	Treatment under claim 1 or 6 where SAHA is the active ingredient	Same schedule as incorporated claim

Both independent claims require the following elements:

A subject with cutaneous T-cell lymphoma.
Oral administration.
A pharmaceutical composition.
SAHA or a pharmaceutically acceptable salt or hydrate.
A pharmaceutically acceptable carrier or diluent.
A specified dose and administration schedule.

The claims use “comprising,” which is an open-ended transition. A product or regimen could contain additional excipients or active ingredients and still fall within the literal claim if all required limitations were present.

How broad is claim 1 covering 400 mg once daily?

Claim 1 covers oral administration of a composition containing SAHA at 400 mg once daily for CTCL. The claim is broad as to the carrier or diluent because it does not require a particular excipient, capsule shell, release profile, or manufacturing process.

Claim 1 does not require:

A gelatin capsule;
Microcrystalline cellulose;
Sodium croscarmellose;
Magnesium stearate;
A particular particle size;
A particular tablet or capsule weight;
A particular brand;
A specific stage of CTCL;
Prior treatment failure;
A particular patient demographic.

Those limitations appear only in dependent claims or in the regulatory indication, not in the basic scope of claim 1.

A generic capsule containing 400 mg of vorinostat and administered once daily would have historically implicated claim 1 if used to treat CTCL during the patent term. The claim did not require the product to be identical to Zolinza. It required the claimed therapeutic use and dose.

What does claim 6 cover for intermittent 300 mg dosing?

Claim 6 covers a different regimen:

300 mg twice daily;
Daily administration for two consecutive weeks;
No administration during the third week;
Repetition of the cycle as medically appropriate.

This is a regimen claim rather than a general dosing claim. A 300 mg twice-daily schedule administered continuously would not satisfy the express “two consecutive weeks, then no administration for one week” limitation. Conversely, the claimed regimen would not require 400 mg once daily.

The claim has commercial significance because it covers a dose-intensified intermittent regimen distinct from the 400 mg once-daily regimen used in the FDA-approved labeling. A product could potentially fall within one independent claim while avoiding the other based on the prescribed dose and schedule.

What do claims 2 through 5 and 7 through 10 protect?

Claims 2 through 5 narrow claim 1. Claims 7 through 10 narrow claim 6.

Dependent claims	Added limitation
2 and 7	Composition is contained in a gelatin capsule
3 and 8	Carrier or diluent is microcrystalline cellulose
4 and 9	Sodium croscarmellose is included as a disintegrating agent
5 and 10	Magnesium stearate is included as a lubricant

These claims describe a conventional immediate-release oral solid dosage form. They do not appear to require a novel controlled-release system, coating, particle-engineering technology, or specialized delivery platform.

The dependent claims create narrower fall-back positions. Their practical value is limited because a formulation that meets claim 1 or claim 6 does not need to include all of the listed excipients. A formulation containing gelatin, microcrystalline cellulose, sodium croscarmellose, and magnesium stearate would satisfy the relevant dependent claim, but a formulation using different excipients could still satisfy the corresponding independent claim.

Does claim 11 cover only the active SAHA form?

Claim 11 requires that the pharmaceutical composition comprise SAHA as the active ingredient. Claims 1 and 6 already identify SAHA or a pharmaceutically acceptable salt or hydrate as the active therapeutic substance. Claim 11 appears intended to emphasize the active-ingredient characterization and may narrow the claim by excluding a composition in which SAHA is present only as an inactive or incidental component.

The claim does not expand the patent beyond the CTCL method, oral route, pharmaceutical composition, and dose schedule incorporated from claim 1 or claim 6.

When did U.S. Patent 7,399,787 expire?

The patent’s statutory term ended January 28, 2022. The relevant chronology is:

Event	Date
Earliest priority date reflected in the patent record	January 26, 2001
U.S. nonprovisional filing date used for patent-term calculation	January 28, 2002
Patent issuance	July 15, 2008
Statutory term end	January 28, 2022
Current enforceability	Expired

The 20-year term is generally calculated from the earliest effective U.S. nonprovisional filing date, not from the issue date. The patent therefore did not receive a new 20-year period beginning in 2008.[1][2]

There is no current enforceable exclusivity under Patent 7,399,787. Any historical Orange Book listing associated with Zolinza did not extend beyond the patent’s term.

What is the FDA regulatory status of vorinostat?

The FDA approved Zolinza on October 6, 2006, for the treatment of cutaneous manifestations in patients with progressive, persistent, or recurrent CTCL on or following systemic therapies.[3]

FDA milestone	Information
Product	Zolinza
Active ingredient	Vorinostat
NDA	021991
Applicant at approval	Merck-related sponsor through the Aton Pharma transaction history
Initial approval	October 6, 2006
Approved dosage form	Oral capsules
FDA-labeled dose	400 mg once daily
Approved disease	Progressive, persistent, or recurrent CTCL
Regulatory pathway	New drug application

The FDA label recommends 400 mg orally once daily with food. The label also includes dose modification instructions for toxicity and circumstances requiring reduction to 300 mg once daily or interruption of treatment.[3]

The 300 mg twice-daily, two-weeks-on and one-week-off schedule in claim 6 is a patent-claimed regimen, but it is not the principal labeled Zolinza dosage regimen.

What is the Orange Book status of Patent 7,399,787?

Patent 7,399,787 was associated with the Zolinza regulatory patent estate and historically identified the dosing-method protection relevant to the approved product. Orange Book listings generally connect a patent to a specific approved drug product and indication. They do not convert an expired patent into an active right.

For current generic-entry analysis, the key point is that the patent term has ended. A generic applicant no longer faces a live infringement risk from this patent for filing, approval, marketing, or prescribing a vorinostat product after expiration.

The patent should be distinguished from:

FDA regulatory exclusivity;
Other Zolinza-related patents;
Formulation patents;
Manufacturing patents;
Patents covering unrelated uses of SAHA;
Patent rights outside the United States.

Were there Paragraph IV challenges to this patent?

A Paragraph IV certification would have been relevant during the patent’s active term if an ANDA applicant asserted that the patent was invalid, unenforceable, or would not be infringed. Once the patent expired on January 28, 2022, the commercial importance of a Paragraph IV challenge ended.

A Paragraph IV filing could still have occurred historically, but the supplied information does not establish a specific challenger, filing date, complaint, settlement, or court disposition. The patent’s expired status is sufficient to resolve the current market-access question: Patent 7,399,787 does not block an ANDA applicant from marketing generic vorinostat in the United States.

Under the Hatch-Waxman framework, a generic applicant may certify that an Orange Book patent has expired or may wait until expiration. The 180-day exclusivity rules applicable to a first Paragraph IV filer do not revive an expired patent or create a continuing exclusion after the patent term ends.[2]

What patent litigation affected Zolinza and vorinostat?

Patent 7,399,787 is no longer an active litigation barrier. Any historical ANDA litigation concerning this patent would have become commercially moot or substantially reduced in significance after the January 2022 expiration date, absent damages or other surviving issues tied to earlier conduct.

The principal litigation risks during the active term would have involved:

Whether a generic label induced treatment of CTCL;
Whether a proposed dosage regimen met the 400 mg once-daily limitations;
Whether a proposed regimen met the intermittent 300 mg twice-daily limitations;
Whether the generic product’s composition included the required carrier or diluent;
Whether the patent was valid and enforceable;
Whether the patent was properly listed for the approved product.

Method-of-use claims can create litigation risk even when the generic product itself is chemically identical to the branded product. The relevant issue is often the proposed labeling and the foreseeable use of the product, not merely the composition.

No current enforceable litigation position can be based on Patent 7,399,787 alone.

How does this patent compare with the broader vorinostat patent estate?

Patent 7,399,787 is narrower than a compound patent and narrower than a broad pharmaceutical-composition patent.

Patent category	Typical protection	Relationship to Patent 7,399,787
Compound patent	SAHA or related hydroxamic acid molecules	Broader chemical protection, generally earlier-expiring
Pharmaceutical composition patent	Dosage form, excipient system, stability, or formulation	May overlap with claims 2-5 and 7-10
Method-of-treatment patent	Use of SAHA for CTCL at specified doses	Category of Patent 7,399,787
Manufacturing patent	Synthesis, purification, crystallization, or solid-state form	Separate technical barrier
Regulatory exclusivity	FDA-based approval protection	Independent of patent scope
Pediatric exclusivity	Six-month FDA extension where granted	Not established for this patent
Biosimilar exclusivity	Biologics Price Competition and Innovation Act protections	Not applicable to vorinostat

Because vorinostat is a chemically synthesized small molecule, biosimilar rules do not apply. The relevant competitive pathway is an ANDA for a generic drug, not a 351(k) biosimilar application.

What formulation and manufacturing barriers remain?

The claims include standard excipients but do not claim an advanced delivery system. The listed formulation limitations are:

Gelatin capsule shell;
Microcrystalline cellulose;
Sodium croscarmellose;
Magnesium stearate.

These components are widely used in immediate-release oral dosage forms. Their inclusion could have created infringement exposure during the patent term, but they do not represent a continuing proprietary barrier after expiration.

A manufacturer could still need to address:

Bioequivalence;
Dissolution;
Stability;
Capsule-shell compatibility;
Impurity control;
API supply;
Process validation;
FDA chemistry, manufacturing, and controls requirements.

Those are regulatory and operational requirements, not continuing patent rights under Patent 7,399,787.

What generic launch scenarios existed and what is the current risk?

During the patent term, three principal launch scenarios existed:

A Paragraph IV launch before expiration, subject to litigation and a possible 30-month stay.
A section viii “skinny label” approach omitting the patented CTCL use, if the remaining labeling did not induce the claimed use.
A post-expiration launch after January 28, 2022.

The third scenario now controls for this patent. A generic manufacturer may market vorinostat after expiration without infringing Patent 7,399,787 merely because its product is used at 400 mg once daily for CTCL.

A skinny-label strategy would have been more difficult for a product whose label or promotional materials expressly directed physicians to the patented CTCL dosing regimen. After expiration, that distinction no longer creates a patent barrier.

What is the geographic coverage of Patent 7,399,787?

The patent provides rights only in the United States. It does not establish protection in:

Canada;
The European Union;
Japan;
China;
Australia;
Other jurisdictions.

Foreign counterparts must be analyzed separately by country, including national-phase status, patent-term adjustments, supplementary protection certificates, opposition proceedings, and local litigation. U.S. expiration does not establish foreign expiration.

How strong was the patent estate for commercial purposes?

During its active term, Patent 7,399,787 had meaningful but limited strength.

Its strengths were:

Clear identification of CTCL;
Specific oral route;
Specific clinically relevant dosing regimens;
Direct alignment with the approved 400 mg once-daily dose;
Dependent claims covering the commercial capsule formulation.

Its limitations were:

It did not cover the underlying molecule broadly;
It did not cover every vorinostat indication;
It did not cover every dose;
It did not cover nonoral administration;
Its formulation claims relied on common excipients;
It was vulnerable to design-around through different schedules or potentially different labeled uses;
It is now expired.

The practical patent value was highest before generic entry and before January 2022. Its current value is historical, evidentiary, and relevant to past infringement analysis, not to prospective U.S. market exclusion.

Key Takeaways

U.S. Patent 7,399,787 covers oral vorinostat treatment of CTCL.
Claim 1 covers 400 mg once daily.
Claim 6 covers 300 mg twice daily for two weeks followed by one week without treatment.
Claims 2-5 and 7-10 add gelatin capsules and conventional excipients.
Claim 11 emphasizes SAHA as the active ingredient.
The patent issued July 15, 2008, and expired January 28, 2022.
It is a method-of-use patent, not the basic compound patent for vorinostat.
The patent does not create a current U.S. generic-entry barrier.
Biosimilar analysis is not relevant because vorinostat is a small-molecule drug.
Historical Paragraph IV and litigation issues centered on induced infringement, claim construction, validity, and label scope.
Foreign patent rights require separate jurisdiction-by-jurisdiction review.

FAQs About U.S. Patent 7,399,787

Does Patent 7,399,787 cover the vorinostat molecule itself?

No. It covers specified methods of treating CTCL with vorinostat. It does not function as a broad composition-of-matter patent for all SAHA uses.

Can a generic company market 400 mg vorinostat capsules now?

Yes, Patent 7,399,787 expired January 28, 2022. Generic marketing remains subject to FDA approval and any other unexpired rights, but this patent alone does not prevent launch.

Does the patent cover vorinostat tablets?

The independent claims require a pharmaceutical composition and oral administration but do not require a capsule. The dependent claims expressly identify gelatin capsules. A tablet could have implicated the broader independent claims during the patent term if it met every required limitation.

Is the 300 mg twice-daily intermittent regimen FDA-approved for Zolinza?

The principal FDA-labeled regimen is 400 mg once daily. The 300 mg twice-daily, two-weeks-on and one-week-off schedule appears in the patent claims but is not the standard labeled dosage regimen.[3]

Are biosimilars a competitive threat to Zolinza?

No. Vorinostat is a synthetic small molecule. Competition proceeds through generic drug applications under the ANDA pathway rather than biosimilar applications under section 351(k).

References

U.S. Patent No. 7,399,787. (2008). Methods of treating cutaneous T-cell lymphoma. United States Patent and Trademark Office.
U.S. Food and Drug Administration. (2024). Approved drug products with therapeutic equivalence evaluations: Orange Book. FDA.
U.S. Food and Drug Administration. (2022). Zolinza (vorinostat) prescribing information. Merck Sharp & Dohme LLC.
U.S. Food and Drug Administration. (2024). Abbreviated new drug application regulations and patent certifications, 21 C.F.R. §§ 314.94, 314.107. FDA.

Country	Patent Number	Estimated Expiration	Supplementary Protection Certificate	SPC Country	SPC Expiration
Austria	462426	⤷ Start Trial
Australia	2003213684	⤷ Start Trial
Australia	2004266169	⤷ Start Trial
Australia	2004283717	⤷ Start Trial
Australia	2008246251	⤷ Start Trial
Australia	2009201668	⤷ Start Trial
>Country	>Patent Number	>Estimated Expiration	>Supplementary Protection Certificate	>SPC Country	>SPC Expiration

Details for Patent: 7,399,787

Summary for Patent: 7,399,787