Download Patent-Extenders

Patent-Extender
Drugs: Loop-holes in
the Law
Sandy H. Yoo
4/14/06
“Patent-extender” Drugs
An increasingly widespread tactic used
by pharmaceutical companies to
extend the life of their drug patents by
creating a slightly altered version of the
original drug, which is then eligible
under FDA rules for at least another
few years of market monopoly.
Novak V. Bristol-Myers Squibb lobbies for a
patent loop-hole. Time Magazine. Nov 2001
Overview of FDA approval
process
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Pre-Clinical testing on animals
Investigational New Drug (IND) Application
Clinical Studies
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Phase I
Phase II
Phase III
New Drug Application (NDA)
NDA review for approval or non-approval
Division Director “sign-off” on new drug
Center for Drug Evaluation
and Research (CDER)
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CDER is FDA’s branch responsible for
approving new prescription drugs and
generic drugs
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They oversee approval of IND, NDA,
and review and give final approval or
disapproval of drugs
Pre-clinical Trials
Manufacturers test their new drug on
animals to ask:
 Is my drug safe to test in humans?
 Is there enough evidence of its
pharmacological action to justify further
clinical studies in humans?
 If the answers are YES, they submit an
IND for approval to test in humans.
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Clinical Studies: Phase I
Initial introduction of new investigational
drug into humans
 Determine drug’s action, properties, and
side-effects in humans
 Usually conducted in healthy human
volunteers

Clinical Studies: Phase II
Early controlled clinical studies to obtain
effectiveness of the drug for a particular
indication
 Usually well-controlled, closely
monitored
 Conducted in a relatively small number
of patients (several hundred people)

Clinical Studies: Phase III
Expanded controlled and uncontrolled
trials to evaluate risk-benefit ratio of
drug
 Involves several hundred to thousands
of people
 Gives basis for extrapolating data
results to general population
 At any of the 3 phases, FDA can place
a clinical hold
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New Drug Application &
Review
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Data from pre-clinical trials and Phases
I, II, III studies become part of the NDA
NDA undergoes formal review by
CDER
The drug can be legally marketed once
division director “signs-off” on new
drug
New Drug Development Process
Generic Drugs Approval
Process
Generics use “abbreviated” new drug
application (ANDA)
 Do not have to include preclinical and
clinical data to establish safety and
effectiveness
 Instead must prove BIOEQUIVALENCE
 If all requirements are met, generic is
approved
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Hatch-Waxman Act 1984
Company can seek approval to market
a generic before expiration of a brandname patent
 “Abbreviated” new drug application
(ANDA)
 1st company to submit ANDA gets 180exclusivity
 Patent holder may file infringement suit
 This delays approval of ANDA for 30months
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NDA’s Drug Classifications
1.
New Molecular Entity
2.
New Salt
New Formulation
New Combination of Two or More Drugs
Duplication of Product (i.e., new
manufacturer)
New Indication (claim) (includes switch
from prescription to OTC)
3.
4.
5.
6.
7.
Already Marketed Drug Product - No Previously
Approved NDA
To name a few…
Original Drug
Ambien
Glucophage
Cipro
Prozac
Paxil
Celexa
Prilosec
Wellbutrin
Symbyax
Claritin
Later Drug
Ambien CR
Glucophage XR,
Glucovance
CiproXR, Proquin
Serafem
Paxil CR
Lexapro
Nexium
Zyban
Olanzapine/Fluoxetine
Clarinex
Manufacturer
Sanofi
Bristol-Myers Squibb
Bayer-Schering
Eli Lily
Glaxo Smith Kline
Forest
AstraZeneca
Glaxo Smith Kline
Eli Lily
Schering
References
1.
2.
3.
US FDA Center for Drug Evaluation and
Research. Available at:
http://www.fda.gov/cder/
Novak V. Bristol-Myers Squibb lobbies for a
patent loophole. Time 2001, Nov 2.
Field A. Doctoring the Hatch-Waxman Act.
Stanford Graduate School of Business
Research Paper.