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January 2019
Impact Of Fdaaa On Registration, Results
Reporting, And Publication Of Clinical Trials
Evaluating New Neuropsychiatric Drugs Approved
Between 2005 And 2014
Constance Xuanyi Zou
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Recommended Citation
Zou, Constance Xuanyi, “Impact Of Fdaaa On Registration, Results Reporting, And Publication Of Clinical Trials Evaluating New
Neuropsychiatric Drugs Approved Between 2005 And 2014” (2019). Yale Medicine Thesis Digital Library. 3547.
https://elischolar.library.yale.edu/ymtdl/3547
Impact of FDAAA on Registration, Results Reporting, and
Publication of Clinical Trials Evaluating New
Neuropsychiatric Drugs Approved between 2005 and 2014
A Thesis Submitted to the Yale University School of Medicine in Partial
Fulfillment of the Requirements for the Degree of Doctor of Medicine
by
Constance Xuanyi Zou
Class of 2019
Abstract
IMPACT OF FDAAA ON REGISTRATION, RESULTS REPORTING, AND
PUBLICATION OF CLINICAL TRIALS EVALUATING NEW
NEUROPSYCHIATRIC DRUGS APPROVED BETWEEN 2005 AND 2014
Constance X. Zou, Jessica E. Becker, Adam T. Phillips, James M. Garritano, Harlan M.
Krumholz, Jennifer E. Miller, Joseph S. Ross
Center for Outcome Research and Evaluation, Department of Medicine, Yale University
School of Medicine and Yale-New Haven Hospital, New Haven, Connecticut
Evidence-based medicine (EBM) promotes the use of randomized controlled trials
(RCTs) published in peer reviewed medical journals as the “gold standard”. However, up
to 50% of the completed clinical trials are never published and trials with results in favor
of studied interventions are 2-4 times more likely to have been published then those with
non favorable results. Publication bias seems to be a particularly severe problem for
RCTs evaluating newly approved brand-name neuropsychiatric drugs. Mandatory trial
registration, and later results reporting, were proposed to mitigate selective clinical trial
publication and outcome reporting. Congress enacted the FDA Amendments Act
(FDAAA) on September 27, 2007 requiring the registration of all non-phase I clinical
trials involving FDA-regulated medical interventions and results reporting for FDA
approved drugs. It’s been 10 years since FDAAA enactment, the impact of FDAAA on
the selective publication of clinical trials has not been studied. Our objective is to
determine whether FDAAA enactment is associated with improvements in trial
2
registration and results reporting, as well as with decreased publication bias of clinical
trials evaluating new neuropsychiatric drugs. We conducted a retrospective cohort study
of all efficacy trials supporting FDA new drug approval between 2005 to 2014 for
neuropsychiatric indications. Trials were categorized as pre- or post-FDAAA based on
initiation and/or completion dates as outlined by the statue. The main outcomes were the
proportions of trials registered, proportions reported results in ClinicalTrials.gov, and the
degree of publication bias. Publication bias was estimated using the relative risks pre- and
post-FDAAA of both the publication of positive vs non-positive trials, as well as of
publishing positive vs. non-positive trials without misleading interpretations. Registration
and results reporting proportions were compared pre- and post-FDAAA using two-tailed
Fisher Exact Test and the degrees of publication bias were compared by calculating the
ratio of relative risks (RRR) for each period. Our study sample included 101 Pre-FDAAA
and 41 Post-FDAAA efficacy trials supporting the FDA approval of 37 new drugs for
neuropsychiatric indications between 2005 and 2014. Post-FDAAA trials were
significantly more likely to be registered (100% vs 64%; P<0.001) and report results
(100% vs 10%; P<0.001) than pre-FDAAA trials. Pre-FDAAA, positive trials were more
likely to be published (RR=1.52; 95% Confidence Interval [CI]=1.17-1.99; P=0.002) and
published without misleading interpretations (RR=2.47; Cl=1.57-3.73; p<0.001) than
those with non-positive results. In contrast, post-FDAAA positive trials were equally
likely to have been published (RR=1; Cl=1-1, p=NA), and published without misleading
interpretations (RR=1.20; Cl=0.84-1.72; p=0.30). The likelihood of publication bias pre-
FDAAA vs. post-FDAAA was greater for publication of positive vs. non-positive trials
(RRR=1.52; Cl=1.16-1.99; p=0.002) and for publication without misleading
interpretations (RRR=2.06, Cl=1.17-3.61, p=0.01). The enactment of FDAAA was
followed by significantly higher proportions of trials that were registered and reported
3
results on ClinicalTrials.gov, and with significantly lower degrees of publication bias
among trials supporting recent FDA approval of drugs for neuropsychiatric indications.
4
Acknowledgement
We would like to thank Dr. Vinay Rathi (Yale University School of Medicine Class of
2015) for his outstanding peer mentorship. We thank the organizers of the Eighth Inter-
national Peer Review Congress (PRC) for giving us the opportunity to present our work,1
and the editors and reviewers who helped us publish our manuscripts in Trials.
1 Video recording of Ms. Zou’s presentation has been made available by the meeting or-
ganizer through Youtube. https://youtu.be/yDKwxE81Tk4
2 Zou CX, Becker JE, Phillips AT, et al. Registration, results reporting, and publication
bias of clinical trials supporting FDA approval of neuropsychiatric drugs before and after
FDAAA: a retrospective cohort study. Trials. 2018;19(1):581.
1
Table of Contents
INTRODUCTION ...........................................................................................................................1
The Role of Randomized Controlled Trials in Modern Medicine ....................................................1
RCT, Gold Standard with an Achille’s Heel. ...................................................................................2
RCT, Gold Standard or Gold Trojan Horse?.................................................................... ...............4
FDAAA: Mandatory Registration and Results Reporting ...............................................................5
STATEMENT OF PURPOSE .........................................................................................................7
METHOD ........................................................................................................................................9
Data Sources .....................................................................................................................................9
Novel Therapeutics Approved for Treating Neurological and Psychiatric Disorders, 2005-2014
...9
Efficacy Trials Supporting FDA New Neuropsychiatric Drug Approval
.......................................10
Determination of FDAAA Status
...................................................................................................11
Determination of Registration and Results Reporting Status on ClinicalTrials.gov ......................11
Determination of Publication Status ...............................................................................................12
Interpretation of Trial Results: Publication vs. FDA ......................................................................12
Validating the Published Interpretations
.........................................................................................13
Calculating the Degree of Publication Bias ...................................................................................14
Data Collection and Data Validation .............................................................................................14
Data Analysis .................................................................................................................................15
RESULTS ......................................................................................................................................16
Characteristics of the Neuropsychiatric Drugs Approved between 2005-2014
..............................16
Table 1. New Drug Applications (NDA) Approved by the FDA between 2005 and 2014 with
Indications for Neurologic and Psychiatric Conditions .................................................................16
Clinical Trials Supporting FDA Approval
.....................................................................................18
Clinical Trial Registration and Results Reporting .........................................................................18
Publication and Published Interpretations .....................................................................................19
Table 2. Characteristics of 142 Efficacy Trials Supporting FDA Approval of NDA for
neuropsychiatric conditions, 2005-2014 .........................................................................................19
Table 3. Publication and Publication-FDA Agreement of Trials Supporting FDA Approval of
NDAs with Neuropsychiatric Indications with Positive, Equivocal, and Negative Results
...........20
Box 1 Examples of Trials Published with Interpretations Disagreeing with the Interpretations of
the FDA medical reviewers. ...........................................................................................................21
Publication Bias .............................................................................................................................25
DISCUSSION ................................................................................................................................26
Study Findings & Prior literature
....................................................................................................26
Implication for Understanding the Impact of FDAAA
...................................................................27
Implications for Future Policy Development
..................................................................................28
Implications for the Practice of Medicine
.......................................................................................28
Limitations ......................................................................................................................................29
Conclusions
....................................................................................................................................30
2
REFERENCE
.................................................................................................................................31
FIGURES, TITLES, AND LEGENDS
..........................................................................................31
Figure 1. Identification of Trials Reviewed by the FDA for New Drug Applications with
Neuropsychiatric indications, 2005-2014 .......................................................................................37
Figure 2 Registration and Results Reporting Status of Trials Supporting FDA Indications by
FDAAA applicability, 2005-2014 ..................................................................................................38
Figure 3. Publication Status and Publication-FDA Agreement of Neuropsychiatric Trials by
FDAAA Applicability and by Trial Results ...................................................................................39
1
Introduction
The Role of Randomized Controlled Trials in Modern Medicine
Randomized controlled trials (RCT) started to have profound impacts on the prac-
tice of medicine today since the rise of evidence-based medicine (EBM) , which has been
defined as “the conscientious, explicit, and judicious use of current best evidence in mak-
ing decisions about the care of individual patients.” (1) However, it is difficult, to put
one’s finger on what made EBM the haute couture, based on its name and such a defini-
tion. Some find it difficult to distinguish the phrase EBM from the word medicine itself.
(2, 3) (3)(4–7)If one were to summarize the teaching of how-to-EBM textbooks and
guides(14–18), EBM method describes an RCT based formula to answer hypothetical
questions involving hypothetical patients with hypothetical diseases related to clinical
care. The main agenda of the EBM campaign is to make sure that RCTs are the best evi-
dence and that only the RCT are good enough to rely on as the “gold standard” for
“judging whether a treatment does more good than harm” (19)because they are “so much
more likely to inform clinicians and so much less likely to mislead them” (than the alter-
natives).(20)(3)(21)
The success of EBM campaign has resulted in many parts of medicine being gov-
erned by RCTs through the Practice Guidelines, which are usually issued by medical pro-
fessional societies outlining best practices. These practice guidelines are welcomed by
physicians who are believers of the power of RCT but find themselves incapacitated by
the complexity of the method and the volume of the work involved in full EBM style in-
vestigation and calculation. The proponents of EBM may object to the idea that EBM en-
courages mindless following of practice guidelines, after all, the physician can and should
2
learn to speak the EBM fluently themselves and use it to guide their day to day practice.
That could happen if the United States suddenly required graduate degrees in statistics for
all medical school graduates; if the physicians have at least days between each appoint-
ment to perform one round of rituals in full as outlined by the 500-hundred page long
EBM bible; (21) and if there is a sudden change of US malpractice law. The truth is the
physicians cannot afford the time or the effort to perform EBM on their own. When they
do try, it usually means a quick PubMed search followed by skimming through the ab-
stracts of a few randomly selected publications of RCTs. They could not afford the lux-
ury sometimes to disobey the order of the “best practice” as outlined in the practice
guidelines, even when they have good reasons to believe it inappropriate for a given set-
ting. They may lose bonuses tied to meeting “quality measures”, which are frequently
based on guidelines, or worse, they can be sued for transgressing the norm as definied by
their professional societies even though it was suppose to be a suggestion.
Practice guidelines are being used in the malpractice arena to define a credible standard
of care to measure the accused physician for an alleged problem addressed. This may
occur despite a medical society's disclaimer that they are not intended, nor devised, for
that purpose. (22)
RCT, Gold Standard with an Achille’s Heel
The EBM formula relies on RCTs published in the literature. The problem is as
many as 50% of completed clinical studies were never published (23–42)What’s more,
trials with non-positive results were significantly more likely to remain unpublished than
trials with positive results and negative results were often manipulated to appear positive.
(39, 43–46)
Experience has shown that such study reports do not always contain a complete, or en-
tirely accurate, representation of study plans, conduct and outcomes. Outright fraud (i.e.,
3
deliberate deception) is unusual. However, incompleteness, lack of clarity, unmentioned
deviation from prospectively planned analyses, or an inadequate description of how criti-
cal endpoint judgments or assessments were made are common flaws. (47)
Because studies were usually considered positive when whatever proposed new in-
tervention works better than a control, publication bias leads to perceived efficacy. EBM
informed clinical practice based on half of the whole truth can result in inappropriate en-
thusiasms for what’s new. Many considered the problems of nonpublication and untruth-
ful publication to be particularly severe among trials evaluating newly approved brand
name neuropsychiatric drugs.(48) Clinical studies supporting approved drugs for neuro-
psychiatric indications, such as paroxetine (Paxil) (49), reboxetine (Edronax )
(50)gabapentin (Neurontin) (51), and lamotrigine (Lamictal) (52), have been identified as
being subject to underreporting. Data demonstrating these drugs to be potentially ineffec-
tive for approved indications or suggesting harm were not publicly disclosed until the
pharmaceutical companies’ internal documents were reviewed during legal proceedings
(53, 54)
Ten years ago, if a psychiatrist were to use the EBM method to calculate and com-
pare the effect size of any of the one dozen antidepressants approved in the previous sev-
eral decades, he or she would find only good news—all of the published trials showed the
drugs to be effective, but in fact only half of the completed trials were. The physician
would overestimate the effect size of each drug for about 30%. (28)Take one of these an-
tidepressants Serzone (nefazodone) for example, which was approved by the FDA in
1994. When the drug was just approved, Bristol-Myers called it a "significant" addition
to the numerous antidepressants with an “additional boost, fewer side-effects—and a
lower price.”(55) It was speculated that the sales of this drug contributed to the fact that
Bristol-Myers Squibb “posted record results for 1996.” (56) While its effective size based
4
on FDA documents was only 0.26. Effect size measures the magnitude of difference be-
tween a given drug and the placebo. 0.2-0.5 is small difference, 0.5-0.8, medium, and
0.8-1, high. 0.26 means the difference between nefazodone and sugar pills are small. Be-
cause its effective size based on the published trials was 69% higher, EBM practice based
on published RCTs would conclude that the drug seem to have a moderate effect. (28) It
is also worth noting this drug was associated with severe liver toxicity and death and was
pulled from the market in 2004. (57–59)
Similarly, among trials evaluating drugs indicated for anxiety (23), and psychotic
disorders (60) that were first approved by the U.S. Food and Drug Administration (FDA)
in recent decades, 80-90% of trials with negative or equivocal results were either not pub-
lished or were published in a misleading manner to suggest a positive result, while nearly
100% of trials with positive results were published.
RCT, Gold Standard or Gold Trojan Horse?
Many feel that this new paradigm brought by EBM based on RCT is doomed to fail
because the industry can and will harness the power of RCT for the benefit of the few. (2,
3, 61–73)
In the perfect world pictured by the proponents of EBM, RCTs are performed by
disinterested researchers who are driven only by the desire to further truth,to improve
care, and to reduce waste. In reality, most large RCT are sponsored by the industry as
business strategy. It is unrealistic to expect that they will always choose to protect the
public interest even at the cost of getting a smaller share of the $3 Trillion that United
5
States spends on healthcare each year, of which 17% were for prescription drugs. (74)
Because of high cost of new drug development, high risk of failure, and high poten-
tial financial gain, conflicts of interest is a particularly serious problem for RCT evaluat-
ing new drugs. With few exceptions, for profit industry are the primary funders of clinical
trials because of the high cost associated with conducting early phase clinical trials to
evaluate drugs that had never been used in humans: Phase II trials can cost up to $20 mil-
lion dollars, while Phase III, up to $50 million each. On average, the cost to run clinical
trials to support the FDA approval of a new drug for a single indications is about 200 mil-
lions dollars. In order for the drug company to profit, not only they need to recover the
astronomical cost invested in the drug targest that received approval, but also those that
did not, which happens 2 to 50 times more often. (75, 76) (77)
FDAAA: Mandatory Registration and Results Reporting
What can be done to prevent the results of completed trials from being swept under
the rug? Publication has always been and will likely remain voluntary, but if the proto-
cols and results of all clinical trials can be found through a publicly accessible, central-
ized trial registry, it would be difficult for the sponsors to withhold trials with unfavora-
ble results or to introduce post hoc analysis to encourage positive interpretations of the
results. Additionally, Journal editors, peer reviewers, and interested members of the pub-
lic could cross reference the results submitted by the sponsors and investigators for publi-
cation.
In 1997, Congress passed the FDA Modernization Act (FDAMA), which mandated
the first U.S.-based public registry ClinicalTrials.gov in 2000 by the National Institute of
Health (NIH) . In 2005, the International Committee of Medical Journal Editors (ICMJE)
6
issued a policy requiring trial registration as a condition of publication in member jour-
nals.De Angelis et al., 2009, #257} Nonetheless, FDAMA only required registration of a
small number of trials, while the ICMJE recommendation was only followed on a volun-
tary basis and still permitted publication of unregistered trials. (78) (79)
In 2007, Congress passed the FDA Amendments Act (FDAAA). At the time
FDAAA was applicable to essentially all non-phase I interventional studies involving
FDA-regulated drugs, biological products, or devices with manufacture site or trial site
based in the United States. FDAAA mandated that sponsors and investigators register all
applicable trials in ClinicalTrials.gov prior to subject enrollment, and report results to
ClinicalTrials.gov within 30 days post approval of the indication being studied. FDAAA
is applicable to trials that began after September 27th, 2007 and to earlier trials that were
still ongoing as of December 26th, 2007. Inappropriately delayed registration and results
reporting, as well as reporting of false results, are punishable by fines of up to $10,000
per day and can lead to withholding of funding from studies receiving federal support.
It has now been ten years since FDAAA was enacted. Its impact on clinical trial
registration, results reporting, and publication bias has largely remained undetermined.
(41)Recently we demonstrated that FDAAA was associated with increased registration
and publication of clinical studies in another study involving new drugs approved to treat
cardiovascular disease and diabetes (CXZ performed data validation and contributed to
the final editing of the manuscript for publication). (80)However, no study has focused
on trials involving drugs treating neurological and psychiatric conditions, an area for
which concern for selective publication and outcome reporting remain.
7
Statement of Purpose
We conducted a retrospective cohort study using efficacy trials that were submitted
to and reviewed by the FDA for the approval of new drug applications (NDA) between
2005 and 2014 for the treatment of neurologic and psychiatric conditions. Our objective
is to compare the rate of registration, results reporting, and the degree of publication bias
for efficacy trials involving newly approved drugs treating neurologic and psychiatric
conditions before and after the enactment of FDAAA. For each trial, we determined
whether a trial is pre- or post-FDAAA based on trial initiation and/or completion dates,
as well as their registration, results reporting, and publication status, Prior to conducting
this study, we put forth the following hypotheses:
1.
There is an association between the FDAAA status, and the likelihood of trial
registration on ClinicalTrials.gov.
2.
There is an association between the FDAAA status, and the likelihood of trial
results reported to ClinicalTrials.gov.
3.
There is an association between the FDAAA status and the degree of publica-
tion bias.
The aim of this study was three fold: (1) to assess the impact of FDAAA on selective reg-
istration and publication of efficacy trials supporting new drugs approved by the FDA to
treat neurologic and psychiatric conditions, (2) to assess the degree of publication bias
8
among trials evaluating newly approved neuropsychiatric drugs, and (3) to inform ongo-
ing efforts to regulate clinical trials registration and results reporting.
9
Method
Data Sources
Data were obtained from three sources: Drugs@FDA , ClinicalTrials.gov and
PubMed’s listing of Medline-indexed journals. Drugs@FDA is a public database
maintained by the FDA, providing access to regulatory actions and documents issued for
each drug approved by the agency. ClinicalTrials.gov is a public clinical trial registry
database maintained by the National Library of Medicine at the NIH (U.S. National
Library of Medicine 2018). PubMed’s list of Medline-indexed journals includes more
than 5,500 biomedical journals.
Novel Therapeutics Approved for Treating Neurological and Psychiatric Disorders,
2005-2014
The Center of Drug Evaluation and Research (CDER), which is part of the FDA,
provides annual reports summarizing all New Drug Applications (NDAs) approved in
each year (U.S. Food and Drug Administration). We downloaded the reports from 2005
to 2014, when available, and otherwise searched Drugs@FDA for those NDAs that were
approved to treat neurologic and psychiatric disorders. Our study sample began with
drugs approved in 2005 to align with our prior work (Downing, Aminawung et al. 2014)
and because an earlier seminal study on the topic examined all antidepressants approved
through 2004 (Turner, Matthews et al. 2008); we chose to exclude drugs approved after
December 2014 to ensure that at least 24 months had passed between drug approval date
and the date when we concluded the final search for the registration record, reported
results and publication, which was March 2017. For each NDA, we recorded its
10
indication, orphan status, priority review status, accelerated approval status, sponsor, and
approval date.
CXZ performed all of the above data collection in the summer of 2016. JSR, as the
principle investigator, reviewed with CXZ the lists of approved NMEs and BLAs
between 2005 and 2014 to ensure that all new drugs approved with neuropsychiatric
indications were included in our sample. JSB, randomly selected 4 drugs using an online
randomizer and validated the data collected for those 4 drugs.
Efficacy Trials Supporting FDA New Neuropsychiatric Drug Approval
As described in a comprehensive tutorial for how to use the Drugs@FDA (Turner
2013), we downloaded the relevant FDA files for each NDA from Drugs@FDA,
including the approval letters, summary reviews, clinical reviews, and statistical reviews.
Among these files, we searched for clinical trials evaluating the efficacy of the drugs
under review. We included only trials for which the FDA discussed and characterized
results, based on the assumption that these trials influenced the FDA’s decision to
approve the study drug for the proposed indication. We excluded ongoing trials, phase
I/safety-only trials, expanded access trials, terminated and withdrawn trials without
enrollment, and trials evaluating indications different than that for which the drugs were
originally approved. We also excluded failed trials. Failed trials were determined by the
FDA and the results of failed trials are invalid. For each included trial, we recorded the
following characteristics: pivotal status, phases, sponsors, study sites, trial length,
randomization, blinding, types of control, description of the treatments, arms of the
investigational drugs, enrollment numbers, and the primary efficacy endpoints. A pivotal
study is defined by the FDA as “a definitive study in which evidence is gathered to
11
support the safety and effectiveness evaluation of the medical product for its intended
use” (2013). Pivotal status was frequently assigned prospectively by FDA, occasionally
assigned retrospectively by the FDA, or at times not assigned by FDA and thus
determined using a previously described method. (Downing, Aminawung et al. 2014) All
searches and data collection were done by CXZ between June 2015 and October 2015.
JSB validated the data collected associated with previously randomly selected 4 NDAs.
Determination of FDAAA Status
At the time when. FDAAA was enacted in 2007, it applied to trials that were
initiated after September 27th, 2007, as well as to trials initiated earlier but still ongoing
as of December 26th, 2007. Based on this, FDAAA applicable trials were categorized as
post-FDAAA, while trials that were initiated or completed prior to the cut-off dates were
categorized as pre-FDAAA. All coding was done by CXZ in the summer of 2015. JSB
validated the data collected associated with previously randomly selected 4 NDAs.
Determination of Registration and Results Reporting Status on ClinicalTrials.gov
To determine whether trials were registered and reported results on
ClinicalTrials.gov, one investigator (CXZ) performed the initial search using the
following terms and their combination: generic, or brand names of the study drugs, drug
indications, trial IDs, trial acronyms, numbers of participants randomized, comparators,
and study time frames. All searches were done by CXZ between the summer of 2015.
JSB validated the data collected associated with previously randomly selected 4 NDAs.
For trials that were not able to be matched with any registration record, a second
12
investigator (JEB) independently performed a second round of searches. No new records
were identified.
Determination of Publication Status
To determine whether trials were published, we searched PubMed for full-length
publications using the same terms as we did for the registration record. Among identified
publications, abstracts and conference reports were excluded. Publications reporting
multiple trials, such as reviews and meta-analyses were also excluded unless the results
of each trial were analyzed and discussed individually in the level of detail as one would
expect from a full-length publication. When the search terms returned too many similar
entries in PubMed, we used Google Scholar to narrow the results. Google Scholar has the
advantage that it can search among the full texts of publications hosted by a variety of
online database or platforms, while for many journals, especially those that require paid
access, PubMed searches only among the title and abstracts. All searches were done by
CXZ between the summer of 2015 and the spring of 2016. JSB validated the data
collected associated with previously randomly selected 4 NDAs. For trials that were not
able to be matched with any registration record, a second investigator (JEB)
independently performed a second round of searches. No new records were identified.
Interpretation of Trial Results: Publication vs. FDA
Trials were classified as positive, negative, or equivocal based on the FDA’s
interpretation of the results as described in Additional File 1. The classification was
based on whether the primary outcome(s) achieved statistical significance while taking
into consideration the summary statements made by the FDA medical reviewers
13
regarding whether or not the findings provide support for the efficacy claim of the study
drugs. Published trial results were categorized similarly based on whether the primary
outcomes achieved statistical significance according to the authors’ analysis while taking
into considerations the authors’ conclusions in the abstract section. Trials with equivocal
or negative results were grouped together as non-positive trials for purposes of
calculating publication bias.
All data collection was done by CXZ between the summer of 2015 and the spring
of 2016. JSB validated the data collected associated with previously randomly selected 4
NDAs. For trials that were not able to be matched with any registration record, a second
investigator (JEB) independently performed a second round of searches. No new records
were identified.
Validating the Published Interpretations
We validated the interpretations of the trial results made by the study
investigators for each publication using the interpretations made by the FDA medical
reviewers found in the FDA approval package as the gold standard. Both the conclusions
in the abstract and the main text of the publications were validated. The two were
considered in agreement if the interpretations were both categorized as positive, negative
or equivocal, and no major contradictions existed between the two statements. As an
example of contradiction between two sources: the published interpretation of trial 02 of
milnacipran (Savella) concluded that “both doses (100 and 200 mg/d) were associated with
significant improvements in pain and other symptoms.” (81) This was considered different from
the statement made by the FDA in the summary review documents, which stated that “[the]
analysis of the ‘pain only’ responders does not indicate that there is a significant effect of MLN
14
(Savella) on pain….(treatment effect) was driven by the patient global response outcome rather
than the pain or function outcome…when studied in isolation, statistically significant treatment
effects for pain and function were not demonstrated.” (82) All coding was done by CXZ in the
summer and fall of 2016. JSB validated the coding associated with the previously
selected 4 drugs. Due to the interpretive nature of this comparison, two additional
investigators (JEB and JSR) reviewed all instances where there was disagreement
between the FDA’s and the authors’ interpretation.
Calculating the Degree of Publication Bias
We calculated and compared two different measures of publication bias between
pre- and post-FDAAA trials. First, we estimated the relative risk of publication of
positive vs non-positive trials in each period. Second, we estimated the relative risk of
publishing positive vs non-positive trials without misleading interpretations in each
period. Thus, publication bias was calculated as the ratio of relative risks (RRR) pre-
FDAAA vs post-FDAAA. CXZ completed the data analysis in fall 2017 and JSR
performed validation of the analysis.
Data Collection and Data Validation
Registration status, results reporting status, publications status, and publication-
FDA interpretation agreement were validated as described previously. We performed a
quality control for the rest of the data set, many of which were collected but not reported
for purposes of this study. A second investigator (JEB) re-collected all data elements
obtained for a random 10% sample of the included new drug approvals, using an online
randomization tool to randomly select 4 out of the 37 drugs. Among the 676 unique data
15
elements collected by the two investigators, the rate of agreement was 99.6% and
disagreements were resolved through consensus.
Data Analysis
We used descriptive statistics to characterize the proportions of trials that were
registered and reporting results on ClinicalTrials.gov. We used two-tailed Fisher Exact
tests to compare the proportions among pre- and post-FDAAA trials. Analysis was
performed using Epi Info Companion App for iOS (3.1.1) (Centers for Disease Control
and Prevention [CDC]; Atlanta, GA) , as well as with MedCalc online statistical software
(2016), supplemented using an online program written by Hutchon (Hutchon 2015) to
calculate the RRRs to estimate both measures of publication bias.
All data analysis was completed by CXZ, JSR independently validated the analysis.
16
Results
Characteristics of the Neuropsychiatric Drugs Approved between 2005-2014
Between January 1st, 2005 and December 31st, 2014, 37 new drugs were approved
by the FDA for the treatment of neuropsychiatric conditions, of which 23 (62%) were
approved for neurological conditions and 14 (38%) for psychiatric disorders, which
included 3 drugs for substance-use related conditions (Table 1). Among the 37 approved
drugs, 34 (92%) were pharmacologic therapies, 3 (8%) were biologics; orphan status was
granted for 9 (24%), priority review status for 6 (17%), and accelerated approval for 1
(3%)
Table 1. New Drug Applications (NDA) Approved by the FDA between 2005 and 2014
with Indications for Neurologic and Psychiatric Conditions.
Brand Name
INN Name
NDA Ap-
plicant
Indication
Ap-
proval
Year
Rozerem
Ramelteon
Takeda
Global
Insomnia
2005
Chantix
Varenicline
Tartrate
Pfizer
Smoking cessation
2006
Azilect
Rasagiline
Mesylate
Teva
Parkinson’s disease
2006
Invega
Paliperidone
Janssen,
L.P.
Schizophrenia
2006
Vyvanse
Lisdexamfeta-
mine Dimesyl-
ate
New River
Attention deficit hyperactivity disorder
2007
Neupro
Rotigotine
Schwarz Bi-
oscience
Parkinson’s disease
2007
Pristiq
Desvenlafax-
ine Succinate
Wyeth
Major depressive disorder
2008
Relistor
Methylnaltrex-
one Bromide
Progenics
Opioid-induced constipation
2008
Xenazine
Tetrabenazine
Prestwick
Huntington's disease
2008
Vimpat
Lacosamide
Schwarz Bi-
oscience
Partial-onset seizure disorder
2008
17
Banzel
Rufinamide
Eisai INC
Seizures associated with Lennox-Gastaut
syndrome
2008
Nucynta
Tapentadol
Hydrochloride
Ortho
Mcneil
Janssen
Acute Pain
2008
Lusedra
Fospropofol
Disodium
Eisai Medi-
cal
Anesthesia
2008
Savella
Milnacipran
Hydrochloride
Cypress Bi-
oscience
INC
Fibromyalgia
2009
Dysport
Abobotuli-
numtoxina
Ipsen Bio-
pharm Lim-
ited
Cervical dystonia
2009
Fanapt
Iloperidone
Vanda Phar-
maceuticals
Inc
Schizophrenia
2009
Saphris
Asenapine
Maleate
Organon
USA INC
Bipolar I disorder
2009
Sabril
Vigabatrin
Lundbeck
Inc
Complex partial seizure disorder
2009
Qutenza
Capsaicin
Neurogesx
Inc
Neuropathic pain
2009
Ampyra
Dalfampridine
Acorda
Therapeu-
tics Inc
Multiple sclerosis
2010
Xeomin
Incobotuli-
numtoxina
Merz Phar-
maceuticals
GMBH
Cervical dystonia and Blepharospasm
2010
Gilenya
Fingolimod
Novartis
Pharmaceu-
ticals Corp
Multiple sclerosis
2010
Latuda
Lurasidone
Hydrochloride
Sunovion
Pharmaceu-
tical INC
Schizophrenia
2010
Viibryd
Vilazodone
Hydrochloride
Trovis Phar-
maceuticals
LLC
Major depressive disorder
2011
Horizant
Gabapentin
Enacarbil
Glaxo
Group LTD
DBA Glax-
oSmithKline
Restless legs syndrome
2011
Potiga
Ezogabine
Glax-
oSmithKline
Partial seizure disorder
2011
Onfi
Clobazam
Lundbeck
INC
Seizures associated with Lennox-Gastaut
syndrome
2011
Aubagio
Teriflunomide
Sanofi
Aventis US
LLC
Multiple sclerosis
2012
Fycompa
Perampanel
Eisai INC
Partial seizure disorder
2012
Dotarem
Dimethyl
Fumarate
Biogen Idec
INC
Multiple sclerosis
2013