Title: Progress and Regression in clinical trials
1Progress 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
2Effect 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.
3Examples 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.
4Potential Cumulative Impact of 4 Simple Secondary
Prevention Treatments
CUMULATIVE BENEFITS ARE LIKELY TO BE IN EXCESS
OF 75 RRR, WHICH IS SUBSTANTIAL
5Questions 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.
6Key Elements of a Good TrialAnswering an
important question reliably.
Randomization Large No. Events Good adherence and
complete followup Unbiased Evaluation
7Complexities 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
8Proliferation 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
9Publics 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.
10Privacy 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
11Good 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.
12Reg 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)
13MRC 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
14Impact 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
15New 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.
16EU 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.
17ICH 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
18On-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
19Examples 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
20Quality 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
21A 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)
22VeGF trial for macular degenerationMedian
simulated P-values (and IQ range)
23A 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
24RCT of onsite monitoingImpact of initiation
visits on patient accrual
No difference
25Impact of initiation visits on volume of data
submitted
No difference
26Impact of initiation visits on quality of data
submitted
No difference
27Prevalence 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
28Impact 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
29Example 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
30COMMIT Example of central checks indicating
problem at one of 1250 participating hospitals
31Statistical 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
32Approaches 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
33Approaches 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.
34Safety 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
35Safety 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
36Alternative 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
37VALIANT
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?
38Effect 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
39Primary 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
40Central 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
41Factorial 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.
42ISIS-2 Study
ISIS 2 Lancet 1988
43Increasing 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
44Intensive 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)
-
45CRASH Trial Death within 14 days
46Increasing 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
47Need 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)
48The Globalization of Cardiovascular Trials
49Globalization of Trials in CVD
50ACTIVE Recruitment, Compliance Data Quality by
High Middle Income Countries
51Globalization 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.
52Barriers 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
53Improving 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