July 1, 2024
“Skinny Labels” for Generic Drugs Under Hatch-Waxman
New “brand-name” drugs are often protected from generic
Pharmaceutical manufacturers may patent a drug’s active
competition by patents. In general, a drug manufacturer
ingredient, drug formulations, methods of using a drug,
intending to market a generic version of a brand-name drug
devices to administer a drug, and methods of making a drug
must either wait for those patents to expire or challenge the
(among other things). A single brand-name drug may be
validity or applicability of the patents in court.
protected by multiple patents that expire at different times.
While some drug patents cover the active ingredient itself,
Orange Book Patents and “Use Codes”
other patents cover different things related to the drug, such
An NDA sponsor must submit to FDA information on any
as a method of using the drug. When some methods of
patent that either (1) claims the drug (i.e., an active
using a drug are still patented but other uses are not, the
ingredient, formulation, or composition patent) or
Hatch-Waxman Act of 1984 (P.L. 98-417) provides a
(2) claims a method of using the drug for which FDA
special process to allow limited generic entry before patent
approval is sought.
expiration. This process—sometimes called Hatch-
Waxman’s “skinny-label” provisions—allows a generic
For method-of-use patents, FDA regulations require the
manufacturer to seek approval from the U.S. Food & Drug
NDA sponsor to include a description of the patent and
Administration (FDA) only for approved uses of the drug
information on whether the patent claims one or more
no longer protected by patents. This In Focus provides
FDA-approved methods of using the drug. This description
background on the skinny-label provisions.
must be adequate to assist future ANDA filers in
determining whether the patent covers a given approved use
New and Generic Drug Approval
(i.e., a drug’s indication). The description provided by the
All new drugs must be approved by FDA before they can
NDA sponsor on method-of-use patents is known as a use
be marketed or sold in the United States. New drugs are
code. The NDA sponsor must also identify the sections of
generally approved by FDA through a new drug application
the proposed drug label that describe the method(s) of use
(NDA). To obtain FDA approval, NDA sponsors typically
claimed by the patent. If the drug is approved, FDA
conduct clinical trials to demonstrate a drug’s safety and
publishes the patent information and use codes (along with
effectiveness—a costly and time-consuming process. NDA
any updates) in a resource known as the “Orange Book.”
sponsors must also submit proposed labeling for the drug
The Orange Book lists all FDA-approved nonbiologic
for FDA’s approval, including the approved indications for
drugs, along with therapeutic equivalence evaluations and
use of the drug (e.g., the diseases or conditions that the drug
information on drug patents and other exclusivities. For
is approved to treat). Although FDA approves new drugs
more information, see CRS In Focus IF12644, Patent
for specific indications, physicians may still prescribe an
Listing in FDA’s Orange Book.
approved drug “off label” to treat other indications that
FDA has not reviewed for safety and effectiveness.
FDA views its authority over patent information in the
Orange Book as “ministerial.” That is, FDA does not
To encourage generic drug entry, Hatch-Waxman created a
independently verify the accuracy of use codes and other
separate pathway for FDA approval through abbreviated
patent information; FDA merely publishes it in the Orange
new drug applications (ANDAs). ANDA filers need only
Book. NDA sponsors must declare, however, that the patent
show that their product is pharmaceutically equivalent and
information they submit is accurate and complete.
bioequivalent to an FDA-approved drug with the same
active ingredient (such that the new drug can be expected to
ANDAs and Patent Certification
have the same therapeutic effect). As a result, generic drug
manufacturers need not conduct their own clinical trials on
Paragraph I-IV Certifications
safety and efficacy, and often sell the drug at lower prices.
Under Hatch-Waxman, ANDA filers must usually make a
ANDA filers must also propose labeling for the generic
certification for each patent listed in the Orange Book for
drug, which generally must be identical to the referenced
the drug at issue. For example, ANDA filers may certify
brand-name drug’s labeling.
that there are no patents listed for the drug or that all the
listed patents are expired. In that case, FDA may approve
Pharmaceutical Patents
the ANDA whenever its review is complete.
Patents, which are granted by the U.S. Patent and
Trademark Office, protect new and useful inventions.
ANDA filers may also may make what is called a
Patent rights last for about 20 years. If the patent is valid,
paragraph IV certification: a claim that the patent is either
no one else may make, use, sell, or import the patented
invalid, or would not be infringed (i.e., violated) by the
invention in the United States during that period without
ANDA filer making and selling the generic drug. Paragraph
permission from the patent holder.
IV certifications often lead to patent litigation in federal
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“Skinny Labels” for Generic Drugs Under Hatch-Waxman
court. If the NDA sponsor timely files suit following a
Justice Sotomayor’s view, the result is “delay and expense
paragraph IV certification, FDA generally cannot approve
the statutory scheme does not envision.”
the ANDA for 30 months while the litigation proceeds
(known as the “30-month stay”).
Skinny Labels and Induced Patent
Infringement Liability
Section viii Statements and “Skinny Labels”
Because the brand-name drug is still protected by one or
Hatch-Waxman provides an additional patent certification
more patents, patients and doctors may use a generic in an
option for method-of-use patents. With a section viii
infringing manner (i.e., for still-patented uses) despite a
statement, an ANDA filer certifies that the patent does not
skinny label. And if a generic manufacturer takes active
cover the uses of the drug for which the ANDA seeks
steps to encourage the patented uses, they may be liable for
approval. Section viii statements are typically used when
inducing patent infringement.
only some approved methods of using the drug are still
patented. Through a section viii statement, an ANDA filer
In GlaxoSmithKline LLC v. Teva Pharmaceuticals USA
may seek FDA approval only for the approved uses of the
(Fed. Cir. 2021), the U.S. Court of Appeals for the Federal
drug that are not patented. Unlike a paragraph IV
Circuit addressed whether generic manufacturers may be
certification, a section viii statement does not delay FDA’s
liable even if they carve out the indications identified in the
ability to approve the ANDA (i.e., the 30-month stay does
Orange Book’s use codes and do not specifically tell
not apply). Along with a section viii statement, the ANDA
doctors to use the generic for carved-out uses. In GSK v.
filer must submit proposed labeling that omits the parts of
Teva, the Federal Circuit affirmed a jury verdict finding the
the brand-name drug’s labeling that correspond to still-
generic manufacturer liable, holding that a jury could find
patented uses. For this reason, generics relying on section
that Teva actively induced patent infringement based on
viii statements are said to “carve out” the patented uses.
generic’s label (which included an infringing indication not
The result is a “skinny label” for the generic version.
identified by the use code), advertising, and press releases.
Judge Prost dissented, arguing that allowing liability in the
Challenges to Orange Book Patent
case “throw[s] a wrench into Congress’s design” for the
Information
skinny-label provisions. Although the U.S. Solicitor
The use codes and label portions identified by the NDA
General urged the U.S. Supreme Court to take the case, the
sponsor define what the ANDA filer must carve out when
Court declined to hear Teva’s appeal in 2023.
using a section viii statement. If the use codes are overly
broad—that is, they extend beyond what a patent actually
Considerations for Congress
claims—then an ANDA filer may be unable to use a section
Following Caraco and GSK v. Teva, some stakeholders
viii statement as a practical matter.
question whether Hatch-Waxman’s skinny-label provisions
remain effective in facilitating partial generic competition
ANDA filers’ ability to challenge the use codes and other
when only some uses of a drug are patented. Should
patent information provided by NDA holders is limited.
Congress seek to clarify the Hatch-Waxman’s skinny-label
While FDA provides a regulatory process to dispute Orange
provisions, there are several possible issues it may consider.
Book patent information, FDA regulations provide that they
will not change the information unless the NDA holder
One issue concerns responsibility for monitoring and
agrees to update or correct it. In the Medicare Prescription
correcting Orange Book patent information. The FDA does
Drug, Improvement, and Modernization Act of 2003
not independently verify listed patents or use codes, and
(MPDIMA) (P.L. 108-173), Congress created a
generic manufacturers have limited means to challenge this
counterclaim allowing ANDA filers to seek a court order
information before filing an ANDA. Because inaccurate use
correcting or deleting Orange Book patent information.
codes may interfere with an ANDA filer’s ability to
Because the counterclaim is not an independent cause of
effectively use section viii statements, generic
action, an ANDA filer cannot assert it unless they are sued
manufacturers may decline to file an ANDA or use
first (e.g., after a paragraph IV certification).
paragraph IV certifications instead. This may lead to
unneeded litigation and delay in some cases. Congress may
In Caraco Pharmaceutical Labs. v. Novo Nordisk (U.S.
consider whether to impose more responsibilities on FDA
2021), the Supreme Court construed the scope of this
to monitor Orange Book patent information, or to expand
counterclaim that MPDIMA created. The Court
current procedures for challenging that information. For
unanimously held that the counterclaim could be used by
example, Congress could consider creating an independent
generics to correct inaccurate use codes (e.g., use codes that
cause of action to correct Orange Book patent information
purport to cover methods not actually protected by patent).
(such as that proposed by S. 1128 in the 118th Congress).
Justice Sonia Sotomayor wrote separately in Caraco to note
GSK v. Teva makes clear that a generic manufacturer, in
her view that the ruling did not fully “fix” the problem of
some circumstances, may be liable for inducing patent
overly broad use codes. As the MPDIMA counterclaim is
infringement when marketing skinny label generics. The
not an independent cause of action, an ANDA filer cannot
case has arguably increased risk and uncertainty for generic
proactively challenge an inaccurate use code in court.
manufacturers when using the section viii pathway.
Rather, they must first make a paragraph IV certification,
Congress may thus consider whether to clarify—via a safe
potentially be sued, trigger the 30-month stay, and only
harbor from liability, or other means—whether or when
then seek to correct use codes via the counterclaim. In
generic manufacturers using a skinny label should be liable
for indirect patent infringement.
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“Skinny Labels” for Generic Drugs Under Hatch-Waxman

IF12700
Kevin J. Hickey, Legislative Attorney


Disclaimer
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https://crsreports.congress.gov | IF12700 · VERSION 1 · NEW

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