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Progress and Regression in clinical trials

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Title: Progress and Regression in clinical trials


1
Progress and Regression in clinical trials
  • 1950-1990 False POSITIVES increasingly well
    controlled by randomisation
  • 1990-2000 False NEGATIVES increasingly well
    controlled by mega-trials and meta-analyses
  • 2000 beyond Increasing regulation,complexity
    and costs may prevent many important public
    health questions from being answered reliably
    (REGRESSION)
  • URGENT NEED TO SIMPLIFY TRIALS TO ENHANCE THE
    CONDUCT OF IMPORTANT TRIALS ESP IN VULNERABLE AND
    UNDERSERVED POPULATIONS BOTH IN DEVELOPED AND
    DEVELOPING COUNTRIES

2
Effect Sizes Diminishing Effects
  • In the current era, where multiple effective
    therapies for a condition already exist, the
    incremental effects of a new treatment may be
    harder to detect
  • Benefits may be more moderate when added to other
    treatments
  • Benefits may be more moderate when tested against
    established treatments (e.g. 10 RRR, not 20
    RRR)
  • Adverse effects may be more than established
    treatments
  • THEREFORE, THE FUTURE GENERATION OF TRIALS
    COMPARING TWO ACTIVE AGENTS MAY HAVE TO BE
    SEVERAL TIMES LARGER THAN INITIALTRIALS OF ACTIVE
    VS CONTROL OR FOR NON INF TRIALS.

3
Examples of Smaller Treatment Effects in the
Modern Era
  • Antiplatelet agents Chronic CADASA vs Control
    25 RRR in vascular events, Thienopyridine vs ASA
    10 RRR, Oral GP IIb/IIIa inhibitors vs ASA
    no diff. AMI 20 RRR of ASA v plac but Clop v
    plac on top of ASA10 RRR.
  • Thrombolytic agents SK vs Control 25 RRR in
    mortality tPA vs SK 10 RRR (in
    mortality/disabling strokes)
  • Bolus new agents vs infusion No diff in
    mortality, but increase in intracranial bleeds by
    30
  • Thrombin inhibitors UFH/LMWH vs Control in UA
    45 RRR, Fonda v Enox 0(20) RRR but 50 RR in
    major bleeds.

4
Potential Cumulative Impact of 4 Simple Secondary
Prevention Treatments
CUMULATIVE BENEFITS ARE LIKELY TO BE IN EXCESS
OF 75 RRR, WHICH IS SUBSTANTIAL
5
Questions that Require Substantial Efficiency in
Costs for Large Trials to be Conducted
  • Non-pharmaceutical Lifestyle modification (e.g.
    wt reduction), surgical procedures, eval
    diagnostic procedures, nutrition supplements or
    mod (e.g. vitamins,breast v formula), health care
    delivery (e.g. parameds to provide antenatal
    care/deliveries, handwashing)
  • Generic drugs New uses of old drugs (e.g. HOPE)
  • Combination therapies (Polypill)/Extending
    duration of therapies (Duration of tamoxifen in
    breast cancer)
  • Developing country questions e.g. Chagas
    disease,HIV, TB ,antithrombotics in resource poor
    settings.

6
Key Elements of a Good TrialAnswering an
important question reliably.
Randomization Large No. Events Good adherence and
complete followup Unbiased Evaluation
7
Complexities of a Trial
Voluminous data/patient
Adjudication
Regulators
Randomization Large No. Events Unbiased Evaluation
Detailed Eligibility
Proliferating Committees
Audits
Multiple approvals
Complex Monitoring
Complex informed consent procedures
8
Proliferation of laws and guidelinesmay make
trial results LESS reliable(and so harm, not
help, patients)
  • Clinical trial conductICH Guideline for GCPEU
    Clinical Trials Directive
  • NHS Research Governance
  • Data access/confidentiality1998 Data Protection
    ActGMC guidance on confidentialityHealth
    Social Care Act/PIAG
  • Ethics consentHelsinki Declaration

9
Publics Attitudes vs Legal/Regulatory
Restrictions
  • Over 98 of the general public do not have
    concerns on data misuse or violation of
    confidentiality in research studies where ethics
    committees have reviewed the protocol.
  • In CRASH, only 1/10,008 enrolled withdrew the
    consent initially provided by the relative. In
    PAC-MAN, only 3.3 refused consent when they
    regained capacity.

10
Privacy and Confidentiality Laws on Clinical
Trials
  • Allow use of medical records to screen patients
    for trials Facilitated by informing all patients
    that this is the case, but they can opt out.
  • -IRBs/ethics committees should be encouraged to
    agree to this
  • Use patient identifiers for follow-up (within and
    beyond the trial) through central mechanisms
    (coordinating center, national registries, etc).
  • Access records to confirm events.
  • 2 and 3 can be facilitated by obtaining the
    consent of the participant

11
Good Clinical Practice?
  • Chiefly a bureaucratic document that is related
    to documentation and mechanics of research and is
    neither good, clinical nor practical for clinical
    trials.
  • Reaction to perceived/documented(rare) sloppy
    data collection, suspicions that investigators
    and sponsors may be dishonest
  • While simple guidelines on ensuring unbiasedness
    and accuracy of data are reasonable, current
    guidelines are far too defensive and make many
    trials of good questions (especially non
    industry) almost impossible to conduct.
  • Suggestion Need new set of sensible guidelines
    by an independent Professional Body (eg.Society
    for Clinical Trials)
  • NBMost trials that have changed practice have
    NOT used GCP.

12
Reg requirements that can be substantially
simplified/eliminated
  • Multiple IRB/REB approvals ( central per country
    /reciprocity)
  • Approved informed consent forms(simplify)
  • All REB amendment approvals(simplify and only
    major changes thru a central website)
  • All future REB annual reviews(?eliminate/post
    progress on a website)
  • Contracts(simplify/standardize)
  • Lab certif and ref normal ranges(only for
    special tests)
  • Import licenses and HQP inspections(?elimin/simpl
    ify)

13
MRC review Potential for EU Clinical Trials
Directive (2001) to be a major obstacle to
important trials
  • Increased bureaucracy due to requirement for
    single sponsor (possibly the funding source)
  • Burdensome drug authorisation and supply (GMP
    labelling) processes
  • Threat to trials of emergency treatments for
    patients unable to give consent
  • Rigid approach to pharmacovigilance and site
    monitoring (through over-interpretation both by
    regulators, pharma beaureacrats and recently
    IRBs)
  • Substantial cost increases may result in fewer
    important trials being conducted

14
Impact of EU Clinical Trials Directive(2001)on
non-commercial cancer trials in UK(Eur J Cancer
2006)
  • Doubling in costs of running non-commercial
    cancer trials and 6-12 month delays to starting
  • Major concerns about correct interpretation due
    to lack of central guidance, lack of clarity
    regarding interpretation of guidance notes, and
    increased documentation
  • Clinical trial units unable or unwilling to start
    in non-UK centres due to different
    interpretations in different European countries

15
New EU Directive 2005/28/EC (Recital
11)simplified procedures for non-commercial
trials
  • Non-commercial clinical trials conducted by
    researchers without the participation of the
    pharmaceutical industry may be of great benefit
    to the patients concerned. The conditions
    under which the non-commercial research is
    conducted by public researchers, and the places
    where this research takes place, make the
    application of certain of the details of good
    clinical practice unnecessary or guaranteed by
    other means.

16
EU definition of non-commercial trials
  • Sponsor is university, hospital, public
    scientific organisation, non-profit institution,
    patient organisation or researcher
  • Data from trial belongs to this non-commercial
    sponsor
  • Design, conduct, recording and reporting under
    their control

  • Impractical
  • No agreement in place between sponsor and
    third parties that allows use of trial data for
    regulatory or marketing purposes and
  • Trial should not be part of the development
    programme for a marketing authorisation of a
    medicinal product.

17
ICH GCP Guidance on monitoring
  • extent and nature of monitoring should be
    based on considerations such as the objectives,
    purpose, design, complexity, blinding, size and
    endpoints of the trial. In general there is a
    need for on-site monitoring before, during and
    after the trial however central monitoring
    can assure appropriate conduct of the trial in
    accordance with GCP
  • ICH GCP 5.18.3

18
On-site monitoring
  • (...) the trial management procedures ensuring
    validity and reliability of the results are
    vastly more important than absence of clerical
    errors. Yet, it is clerical inconsistencies
    referred to as errors that are chased by the
    growing GCP-departments.
  • Refs Lörstad, ISCB-27, Geneva, August 28-31,
    2006
  • Grimes et al, Lancet 2005366172

19
Examples of Cost Escalations that Damage the
Feasibility of Trials
  • CREATE-ECLA(20,000 AMI eval GIK/LMWH) Costs for
    a CRO in India to obtain regulatory approvals,
    import and distribute drugs exceeded the entire
    study budget
  • UNNAMED TRIAL A trial of 20,000(statin/combo BP
    lowering) followed for 5 years proposed at a
    total cost of 80 million. Funding approved by
    XYZ company.
  • -Added complexities related to monitoring,and
    perceived regulatory requirements , escalated
    costs to 140 million. Funding withdrawn.
  • -Revised simple trial with 10,000 (higher risk)
    individuals ongoing at 30 million

20
Quality Assurance why ?
  • The purpose of quality assurance is not to ensure
    that individual data items are 100 error-free.
  • Its purpose is to ensure that the clinical trial
    results are reliable, i.e.
  • observed treatment effects are real
  • their estimated magnitude is unbiased

21
A taxonomy of errors
  • Random errors (Random with respect to treatment
    assignment and unlikely to materially influence
    study results , unless large).
  • Measurement errors (eg due to assay precision or
    frequency of visits)
  • Errors due to transcription errors,variations in
    entry criteria.
  • Some types of fraud (fabrication of non key
    data items)
  • Systematic errors(Differential with respect to
    treatment assignment and could substantially bias
    results).
  • Design flaws (eg post rand exclusion,biases in
    event ascertainment,failure to use intent to
    treat)
  • Some types of fraud (usually with knowledge of
    treatment assignment as in a single center study)

22
VeGF trial for macular degenerationMedian
simulated P-values (and IQ range)
23
A randomized study of the impact of on-site
monitoring
Stratify by - Type (Academic vs Private) -
Location (Paris vs Province)
Centers accruing patients in trial AERO B2000
Group A (site visits)
Group B (no visits)
Ref Liénard et al, Clinical Trials 200631-7
24
RCT of onsite monitoingImpact of initiation
visits on patient accrual
No difference
25
Impact of initiation visits on volume of data
submitted
No difference
26
Impact of initiation visits on quality of data
submitted
No difference
27
Prevalence of fraud?
  • Industry (Hoechst, 1990-1994)1 case of fraud in
    243 (0.43) randomly selected centers
  • FDA (1985-1988)1 of 570 routine audits led to a
    for-cause investigation
  • CALGB (1982-1992)2 cases of fraud in 691 (0.29)
    on-site audits
  • SWOG (1983-1990)no case (0) of fraud in 1,751
    patients
  • McMaster(1992-2007) 2 (0.1) in 46 trials
    involving gt250,000 patients from over 5000
    centers.
  • ?fraud is probably rare (but possible
    underestimation esp in era of paying more than
    the costs of trials?)
  • Ref Buyse et al, Statist in Med 1999183435

28
Impact of fraud
  • Most frauds have little impact on the trial
    results(unless widespread or at central) because
  • they introduce random but not systematic errors
    (i.e. noise but no bias) in the analyses
  • may affect secondary analysis (e.g. subgroup
    analyses if baseline data are incorrect)
  • their magnitude is too small to have an influence
    (one site and/or few patients)
  • Refs Altman, Practical Statistics for Medical
    Research 1991
  • Peto et al, Controlled Clin Trials 1997181

29
Example of fraud detection thru central checks
  • Invitation to collaborate in being a coauthor(by
    Dr XY thru well respected invest and friend) on a
    paper demonstrating the marked benefits of a Vit
    in individuals with specific genotype in
    preventing CVD.(Result would have major
    implications, attract great attention, and
    targetted for a leading journal).
  • Requested the data base randomization did not
    match various explanations of process and
    sequence,diff in events marked and early(both
    implausible), event rate patterns and rates not
    clinically consistent ,indication of an
    independent DSMB who stopped the trial but
    named chair unaware of even being on the
    DSMB(who was named as the last author and thru
    whom my involvement as a coauthor was requested).
  • WE PROVIDED A REPORT OF OUR FINDINGS AND DECLINED
    PARTICIPATION

30
COMMIT Example of central checks indicating
problem at one of 1250 participating hospitals
31
Statistical approaches to data checking
  • Humans are poor random number generators ? test
    randomness (e.g. Benfords law)
  • Plausible multivariate data are hard to fabricate
    ? test correlation structure
  • Clinical trial data are highly structured?
    compare expected vs observed
  • Clinical trial data are rich in meaning? test
    plausibility (e.g. dates)
  • Fraud or gross errors usually occur at one
    center? compare centers

32
Approaches to Study Monitoring (1)
  • Trial oversight Operations or Trial Management
    Committees, Steering Committee, Independent Data
    Monitoring Committee
  • Central Monitoring
  • -fax consent forms centrally
  • -central faxing of key documents (e.g. ECGs,
    laboratory reports, discharge summaries)

Statistical Monitoring
33
Approaches to Study Monitoring (2)
  • 3. On Site Monitoring
  • a) Random and infrequent
  • b) Guided by Central Monitoring
  • c) Onsite mentoring instead of monitoring
  • A combined approach of central with directed
    onsite monitoring(random and for cause) is likely
    to be both efficient and effective.

34
Safety Monitoring, Reporting and Reviewing AEs
  • Current
  • Any event including those that are the outcomes
    of interest,and events that are common in the
    condition of that age are considered to be AE
  • -They(sometimes even the primary outcome) are
    often recorded, reported (expedited)
  • -Reviewed individually,so difficult to discern
    patterns
  • -Unblinded, and SAEs in the active group only are
    reported to investigators, their IRBs and to
    regulatory authorities

35
Safety Monitoring, Reporting and Review
  • Problems
  • -Enormous amount of effort (upto about 25 hrs/SAE
    reported) BUT is it useful and worthwhile?
  • -Misleading as to the safety situation of the
    trial,as no between group comparisons are
    possible and impossible to reliably attribute
    causality on a case by case basis (except perhaps
    for very unusual events eg thrombocytopenia or
    liver failure).
  • -Lack of a balance between safety and efficacy,
    e.g.in OASIS 5, catheter thrombosis (excess of
    0.2), bleeding (reduced 2.5), mortality
    (reduced 1.0) with fonda in OASIS-5

36
Alternative Approach to Adverse Event Reporting
and Review
  • Report all relevant data to a coordinating
    center, which regularly shares SAE and efficacy
    to the DSMB.
  • Report to regulatory bodies and centers, only if
    the DSMB judges that harm exceeds benefit

37
VALIANT
Central Events Committe versus Site Investigator?
  • 11,751 events reviewed in VALIANT
  • Events identified by Site Investigator

Events Agee Cause of Death 2897 66 CHF 384
1 73 MI 2159 63 Resucitated Death 636 27 Strok
e 541 91
Who is correct? Investigator with more clinical
info or the comm thousands of miles away?
38
Effect of Adjudication on Estimated Treatment
Effect McMaster Experience(108,000 pts)
Adjud. Investigator OR OASIS-1 0.70 0.71 0.99 OA
SIS-2 0.90 0.85 1.06 HOPE 0.78 0.80 0.98 HOPE-2 0.
95 0.93 1.02 CURE 0.82 0.80 1.03 OASIS-5 1.01 1.01
1.00 OASIS-6 0.86 0.86 1.00 CREATE 0.87 0.87 1.00
WAVE 0.82 0.94 0.87 ACTIVE-W 1.43 1.42 1.01
39
Primary Endpoint Results According to Adjudication
Treated Placebo P-value EPIC Adjudicated
8.3 12.8 0.009 Investigator 9.0 12.4 0.12
0 IMPACT II Adjudicated 9.2 11.4 0.063 Inves
tigator 5.5 7.8 0.018 GUSTO IIB Adjudicated
8.9 9.8 0.058 Investigator
8.4 9.6 0.016 PURSUIT Adjudicated
14.2 15.7 0.04 Investigator
8.0 10.0 0.0007 CHARM-Preserved
Adjudicated 22.0 24.3 0.12 Investigator
21.4 24.7 0.028
40
Central Adjudication of Events When and to What
Degree?
  • Not needed Hard endpoints, especially blinded
    studies
  • Needed for open trials, especially when the
    outcome may be subject to interpretation
  • Occasionally Central screening for missed
    events
  • Fundamental need is to avoid BIASES and LARGE
    MISCLASSIFICATIONS
  • Accuracy may be enhanced by collecting
    information on CRFs on outcomes in a structure
    than matches protocol definitions

41
Factorial Designs
  • Increased efficiency as two for the price of
    one
  • Only way to answer generic questions, by
    piggybacking it to a more fundable question
  • Avoid overfactorializing (e.g. 2x2x2x2)
  • Our approach ALWAYS try to factor a generic
    question(Vit, fish oils,GIK,intervention type or
    procedures, lifestyles, vaccines,etc), unless
    impossible.
  • FACTORIAL DESIGNS ARE UNDERUTILIZED DUE TO BOTH
    ACADEMIC, INDUSTRY AND REGULATORY FEARS THAT
    QUALITATIVE INTERACTIONS WILL OCCUR THAT ARE
    LARGELY MISPLACED.

42
ISIS-2 Study
ISIS 2 Lancet 1988
43
Increasing Clinical Trials in Disadvantaged/Vulner
able Populations (1)
  • 90 of the global burden of disease occurs in LIC
    MIC yet only 10 of the 70 billion of the
    research expenditures occur in these countries,
    e.g. Chagas disease affects 18 mill people in L.
    America yet only 4 RCTs involving 800
    individuals followed for 3 to 6 months are
    available .BENEFIT 3000 patients x 3 yrs,
    evaluating benznidazole T.B. pericarditis (50 6
    mo mortality), no major trials.IMPI steroids and
    a vaccine in 800( 3000) people.
  • Neglected populations e.g. children, vulnerable
    groups, etc.
  • Neglected conditions, e.g. road traffic accidents
    (CRASH steroids in head injuries), cardiac
    arrest, other critical illness

44
Intensive care management of severe head injury
  • Percent therapy for intracranial
    hypertension
  • 1995 USA 1996 UK No.pts(trials) OR(CI)
  • Barbiturates 33 56 208(3)
    1.09(.91,1.47)
  • Corticosteroids 64 49 2119(16)
    0.96(.85,1.08)
  • CSF drainage 44 - 0(0) --
  • Hyperventilation 83 100 77(1)
    0.73(.36,1.49)
  • Mannitol 83 100 44(1) 1.75(.48,6.35)

45
CRASH Trial Death within 14 days
46
Increasing Clinical Trials in Disadvantaged/Vulner
able Populations (2)
  • Consider trials with consent of relatives or
    surrogates and when time is of the essence
    perhaps without any consent but IRB approvals
  • CRASH

47
Need for Randomized Trials in Developing Countries
  • Global disease burden occurs largely in
    developing countries, but few RCTs (e.g. only 3
    trials in Chagas disease, no large trials in TB
    pericarditis or Rh Heart disease)
  • Simple, widely practicable therapies are likely
    to have greater impact than complex, expensive
    treatments
  • The same disease, its manifestations, its
    severity and complications may vary or progress
    very different ways in developing countries
    compared to developed countries
  • TRIALS HAVE SCIENTIFIC, POLITICAL AND
    DEMONSTRATION VALUES THAT OFTEN HAVE TO BE
    REESTABLISHED IN MANY DIFFERENT SETTINGS (E.G.
    BCG VACCINE TRIALS OR VITAMIN A SUPPLEMENTATION)

48
The Globalization of Cardiovascular Trials
49
Globalization of Trials in CVD
50
ACTIVE Recruitment, Compliance Data Quality by
High Middle Income Countries
51
Globalization of Trials in CVD
  • 1. Most CVD trials include LIC/MIC to reduce
    costs and speed enrollment, and are primarily
    aimed at answering questions relevant to the
    West.
  • BUT, these trials may also have applicability in
    LIC/MIC if the condition is common and the
    treatments are affordable.
  • 2. Need trials in LIC MIC of locally relevant
    conditions and treatments, and locally conducted.

52
Barriers to Funding Global Trials
  • No (e.g. in LIC/MIC) or modest investment in
    clinical trials by governmental/charitable bodies
    even in Western countries (usually 2 to 8, in
    Canada about 4)
  • Balkanization in funding (e.g. HSFS in Canada or
    need special justification to include foreign
    centers) and restrictions in their use by
    territory (e.g. by province or country)
  • Misperceptions about the importance of large
    clinical trials (cookbook and mundane) vs basic
    science (more fundamental and exciting
  • Perception that clinical trials funding should be
    left to industry

53
Improving global health thru reliable trials of
important questions
  • Randomize a large number of (high risk)
    individuals
  • Minimize data collection per subject drastically
  • Minimize complexities (e.g. adjudicatIion,
    monitoring, standardization, AE reporting,
    approvals, etc.)
  • MANY MORE trials with factorial designs.
  • Need more trials in vulnerable populations and
    developing countries, where the disease burdens
    are the largest
  • PARADOXICALLY LESS MONITORING, ADJUDICATION,
    AUDITING etc,AND DELIBERATE SIMPLIFICATION LEAD
    TO MORE RELIABLE RESULTS
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