Outline

• General endpoint considerations

• Surrogate endpoints

• Composite endpoints and recurrent events

• Safety outcomes (adverse events)

Outline

• Some background

• Definitions

• Data collection considerations

• Reporting of safety outcomes

• Recommendations

Safety Outcomes: Some Viewpoints

• The collection of safety outcomes in trials is often not done with same rigor as efficacy outcomes (e.g., less focused, less thought given to data collection protocol).

• Safety reporting in trials and in systematic reviews is inadequate (this is also true for interim analyses) (Ioannidis,

JAMA 2001, and Ernst, BMJ 2001). CONSORT guidelines were modified in 2004 (Ann Intern Med).

• Major safety outcomes should be recorded irrespective of attribution to study treatment.

• Safety is best assessed using aggregated data against a randomized control.

• Safety of treatments is not known with certainty until they have been used for many years (Lasser, JAMA 2002).

FIAU for Hepatitis B Virus Infection

• FIAU’s toxicity mimicked the underlying disease and other medications taken by the patients (hepatic and pancreatic adverse events not attributed to the treatment).

• FIAU’s toxicity was not predicted by animal studies.• Each adverse event was considered separately – no

cumulative analysis of events by treatment group.• In NIH trial, 15 patients were randomized to 2 doses of

FIAU for 24 weeks (no placebo control).• Study stopped because one patient developed liver failure. • Ultimately, 7 patients experienced severe liver toxicity and

5 died after cessation of study treatment.• Retrospective review of 2 other studies revealed delayed

toxicities of FIAU.

N Engl J Med 1995; 333: 1099-1105.

Regulatory and Scientific History of Rosiglitazone

• Approved by FDA in 1999 on the basis of short-term studies indicating it lowered glucose and HbA1c.

• Questions about safety arose based on a meta-analysis by Nissen and Wolski in 2007.

• FDA advisory committee concludes that rosiglitazone increases risk of MI compared to placebo and notes limitations of meta-analysis. FDA adds “boxed” warning, recommends long-term head to head comparison with another diabetes drug to compare CVD outcomes, but does not withdraw drug from the market.

• Trial is initiated (TIDE trial), ethics of clinical trial questioned, Senate Finance Committee discusses data and ultimately trial discontinued and severe restrictions placed on use of the drug.

IOM Report 2012, Ethical and Scientific Issues in Studying the Safety of Approved Drugs.

June 2013 Update

• FDA Panel reviews CVD safety data again– 13 panel members vote to ease up risk

mitigation strategy, including special certification to use it.

– 7 vote to remove all restrictions– 5 vote to continue current restrictions

Some Lessons Learned (Maybe) from Rosiglitazone

• Short-term studies using surrogate outcomes are not powered to identify clinically relevant safety signals.

• Many trials done for registration are not conducted to reliably assess major safety issues (e.g., data not collected following treatment discontinuation, major clinical outcomes not collected in a standardized manner, good meta-analyses hard to do).

• It is difficult to do a trial to confirm a safety signal.

Guidance Documents

• International Conference on Harmonization (ICH) of Technical Requirements of Pharmaceuticals for Human Use

– Clinical Safety Data Management: Definitions and Standards for Expedited Reporting E2A

• Regulatory authorities have reporting requirements for adverse events– Code of Federal Regulations (CFR) Title 21, Part 312

describes safety reporting for investigational drugs (trials being carried out under an IND with the FDA)

– EU Directive provides guidance for reporting safety data for investigational medicinal products

Types of Safety Outcomes (1)

• Adverse events that require reporting to regulatory authorities– Serious Adverse Events (SAEs)– Suspected Unexpected Serious Adverse Reaction

(SUSARs)

• Adverse events for planned treatment comparisons– Treatment discontinuation due to adverse effects– Adverse effects according to severity by standard

grading table• Open-ended • Side effect check-list

Types of Safety Outcomes (2)

• Another way of thinking of the categorization:– Case reports of individual events– Data on case report forms with which to

compute counts and rates of events by treatment group

• Both are important (refer to week 1 notes for discussion of case histories and series)

Serious Events Definition – ICH Guidelines

• Events resulting in death

• Life-threatening events

• Events leading to hospitalization or prolonging existing hospitalization

• Events leading to persistent/significant disability or incapacity

• Congenital abnormalities/birth defects

• Other important medical events that may jeopardize the participant or require intervention to prevent one of the other outcomes above

Other Definitions

• Unexpected – an adverse drug experience which is not consistent with the current investigator brochure (or label for approved drug)

• Related – cannot rule out the possibility that the treatment caused the adverse event (i.e., the investigator cannot check “not related”)

SUSARs

• SUSAR=Suspected Unexpected Serious Adverse Reaction

• SUSAR reporting is required by the European Union (EU) Directive 2001/20/EC for all trials being conducted at sites in the European Economic Area (EEA) that use investigational medicinal products (IMPs)

What is a SUSAR?

• Serious: per ICH GCP Guideline E2A

• Unexpected: per labeling of the suspect agent

• Suspected adverse reaction: related to treatment

Recommendations for Reporting Serious Adverse Events

• Require serious events to be reported on all participants, regardless of treatment status or relationship to study treatment (attribution is unreliable and hard to standardize).

• This allows a randomized comparison of the occurrence of serious events over the course of the trial

• Establish systems to meet expedited reporting requirements by regulatory authorities (within 7 days of awareness) – IND safety reports for serious adverse events (SAEs)

associated with the treatment and unexpected (e.g., see 21 CFR 312.32 for drugs)

– SUSARS

Informing Investigators, IRBs and Ethics Committees

• Individual case reports of SAEs or SUSARs sent to all investigators using the investigational product by sponsor or designee (e.g., an investigator may receive safety reports for patients in another institution and in another trial)

• Investigators notify IRB/EC

• Sponsor updates investigator brochure on a regular basis

• Problem: Numerators and not denominators

Collection of Safety Outcomes in Clinical Trials - Considerations

• Where do you draw the line?– Collect all adverse events irrespective of severity?– Only serious adverse events?– Only why the participants is taking the study treatment?

• Standardization– Tables for grading AEs for severity– Open-ended or checklist– MedDRA coding– Event review committee

• More detailed data collection is important in early phase studies.

• Describe safety data collection and reporting in the protocol and in the trial report

Adverse Events in Cancer Treatment Trials: An Evaluation

• Evaluation of 75, 598 “routine” adverse events collected on 1,181 patients between 1999 and 2001.

• An average of 2,588 adverse events per study.

• Most adverse events reported were mild; 3% were severe; 1% required expedited reporting

• Much of what is collected is not reported.

Mahoney M, et al, J Clin Oncol 2005; 23:9275-9281

Do Not Try to Collect All Adverse Events• You will fail!

• Bradford Hill suggested the following 3 questions be asked by the person developing a case report form:– Is this question essential?– Can I obtain useful answers to it?– Can I analyze them usefully at the end?

• Peto is less diplomatic: “…the statistician should, at the design stage, cross out most of the things that the trial organizer wants to ask.”

Principles of Medical Statistics and Biomedicine 28:24-36, 1978.

A Minimalist’s Approach: Composite Hierarchical Outcomes for Safety

Treatment

A B

Death

Death or SAE

Death, SAE, or Severe AE

Death, SAE, Severe AE, or Treatment D/C due to AE

Collection of Safety Data in a Subsample

• Herpes zoster (shingles) vaccine trial; 38,546 participants 60 years of age and older

• Safety evaluation– Adverse events within 42 days of vaccination for

all participants– Serious adverse events for all of follow-up (3+

years) for all participants– Substudy of 300 participants to closely monitor

symptoms using a checklist within 42 days of vaccination

N Engl J Med 2005; 352: 2271-2284.

Sample Toxicity Table for Grading Severity of Adverse Events

Grade 1Mild

Grade 2Moderate

Grade 3Severe

Grade 4Potentially

Life-threatening

Allergic Reaction Pruritis w/o rash

Localized urticaria

Generalized urticaria or angiodema

Anaphylaxis

Creatinine >1 – 1.5 ULN

>1.5 – 3 ULN

>3.0 – 6 ULN > 6.0 ULN

Generic Grades

Structured (Checklist) vs. Unstructured (Open-Ended) Data Collection

• Structured data collection is easier to standardize, process and analyze

• Structured data is easier to combine across investigators/studies

• Greater chance of missing something with structured data collection

• No or less freedom of expression with structured data collection

Checklist versus Open Response

1) “Did you look at any of the following newspapers or magazines or journals yesterday? Put a tick (√) against each of them that you definitely looked at yesterday. Put a cross (X) if you did not look at it yesterday.”

Daily Mail [ ]

The Times [ ]

Daily Herald [ ]

•

•

List all others:

Belson W., Duncan J. Applied Statistics, 1962.

2) “Did you look at any newspapers or magazines or journals yesterday? This would include daily papers, Sunday papers, weeklies and any that come out monthly. Write down the name of each that you definitely looked at yesterday.”

Average Number of Publications Identified in the √ List

Daily - - 1.52 1.12

Sunday 1.72 1.23 - -

Weekly & Monthly 0.78 0.17 0.90 0.23

Type ofPublication

Group 1 Group 2

√ List

OpenResponse √ List

OpenResponse

Daily Papers on the √ List

Daily Mail 16 12 0.78

The Times 4 3 0.70

Daily Herald 9 5 0.54

Evening News 39 27 0.70

Daily Mirror 46 39 0.85

Star 21 12 0.56

Daily Telegraph 17 13 0.77

Percent√’d

PercentMentioned withOpen Response Ratio*

* Before rounding

Average Number of Publications Identified Which Did Not Appear in the √ List

Daily - 0.06 0.35 0.61

Sunday 0.18 0.26 - -

Weekly & Monthly 0.29 0.39 0.33 0.57

ALL 0.47 0.71 0.68 1.18

Type ofPublication

Group 1 Group 2

√ List

OpenResponse √ List

OpenResponse

Daily Papers Mentioned Under “All Others” on the √ List

News Chronicle6 7 1.12

Daily Express 15 25 1.72

Daily Sketch 7 13 1.95

Evening Standard 5 10 1.94

All Others 3 5 1.99

PercentMentioned withOpen Response

* Before rounding

PercentMentioned Under

“All Others” Ratio*

Belson and Duncan Conclusions1. There is a sharp difference in the two methods indicating that

at least one of them may be in error when assessing yesterday’s behavior.

2. The yields from the two systems cannot be compared or pooled either within a survey or between surveys.

3. One cannot assume that by using an “all others” response in √ list that the problem of not having an exhaustive √ list is solved.

4. Unstructured questions provide more freedom of expression and structured questions allow less expression of individuality.

5. Some TV programs which were not broadcast the day before were included in the √ list and actually checked by some respondents. They were not mentioned in the open response suggesting an inflating tendency with the √ list.

Implications of Belson and Duncan’s Work

Collection of Adverse Events in Clinical Trials.

A Randomized Trial of Methods for Assessing Medical Problems - 1

• After taking placebo for 1 month (as part of a run-in to a trial) 214 men with benign prostatic hyperplasia were randomly assigned to 3 methods for collecting adverse events.

• 3 self-administered forms used.

• No assessment of severity; responses to open-ended questions were recorded

Bent S et al, Ann Intern Med 2006; 144:257-261.

Open-EndedQuestionnaire(N=70)

Open-Ended Defined Question (N=70)

Checklist (N=74)

Total Adverse Events Reported

11 14 238

No. (%) with Event

10 (14.3%) 9 (12.9%) 57 (77.0%)

A Randomized Trial of Methods for Assessing Medical Problems - 2

Open-Ended Questionnaire: “Did you have any significant medical problem since your last visit?”

Open-Ended Defined Question: “Since the last study visit, have you limited your usual daily activities for more than 1 day because of a medical problem?”

Checklist: “Since the last visit, have you experienced any of the following?” (53 symptoms)

Example: Aspirin vs. Placebo in AMIS Study

(See Chapter 11 of Friedman, Furberg, and DeMets)

Volunteered 1.29 0.45(open-ended)

Elicited 4.86 2.99(√-list)

Reason for 0.22 0.04dosage reduction

Bloody Stools Aspirin PlaceboPercent Ever Reporting

Visit-Driven Checklist

Open-Ended Questionnaire for

Serious Events•

Event-Driven Form

MedDRA Medical Event Coding

• Medical Dictionary for Regulatory Activities

• Used in U.S., EU, and Japan; mandated for safety reporting in EU and Japan

• Each event assigned an 8-digit number

• Multi-axial: one event may be linked to multiple System Organ Classes

Cardiac Disorders SOC

Coronary Artery Disorders HLGT

Ischaemic Coronary Artery Disorders HLT

Myocardial Infarction PT

Heart Attack LLT

MedDRA Example

System Organ Class SOC(n=26)

High Level Group Term HLGT(n > 300)

High Level Term HLT(n > 1,600)

Preferred Term PT(n > 18,000)

Lowest Level Term LLT(n > 66,000)

MedDRA Hierarchical Structure

Questions to Consider in Reviewing a Trial Report

Was event ascertainment similar for the treatments under study?

When did collection of AEs begin and end?

What was the timing of follow-up assessments for adverse events?

How were AEs defined?

Were severe events centrally reviewed and adjudicated?

Reporting of Adverse Events- 1

“Grade 4 events were reported irrespective of their perceived relationship to the use of interleukin-2 or antiretroviral therapy and were coded according to the Medical Dictionary for Regulatory Activities (version 12.0)”

ESPRIT HIV Study. N Engl J Med 2009; 361:1548-59.

Reporting of Adverse Events - 2

“The study was designed as an intention-to-treat analysis with data of clinical events (excluding survival) and each subject’s tolerance censored at the termination of the study medication.”

AIDS 1994;8:1185.

Reporting of Adverse Events - 3

“We used a five-point scale…to grade adverse events occurring while the patient was taking study drugs and during the eight weeks after their permanent discontinuation”.

“All analyses were performed according to intention to treat”.

N Engl J Med 1996;335:1099-1106.

Recommendations - 1

• Many trial reports are lacking in terms of safety data collection and reporting limiting the ability to weigh risks versus benefits.

• Collect less, better, and report it.

• Often a combination of “visit-driven” and “event-driven” data collection is optimal with use of both a checklist and open-ended response questions.

Recommendations - 2

• Collect safety outcomes for entire trial duration irrespective of relationship to treatment.

• Some treatments, even if taken for a short period of time, may delay or reverse disease progression.

• Likewise, some treatments, even if taken for a short time, may cause toxicities (e.g., liver damage, an acceleration of atherosclerosis) that may not manifest themselves while taking the treatment.

• A “Consumer Reports” analysis of safety and efficacy outcomes is helpful, but cannot be done reliably unless you collect data on all patients for the duration of the study.

• I

Recommendations - 3

• Composite hierarchical safety outcomes can be useful to supplement an analysis of the individual safety components.

• Interim treatment comparisons, for which numerators and denominators are available, are the most important component of safety monitoring. These must be done to supplement the requirements for reporting individual case summaries to IRBs/ECs and regulatory authorities.

New Draft Guidance from the FDA

• Targeted data collection based on stage or research

• Pre-identification of data not necessary to collect

• Collection of data in a subsample

• Decreased frequency of laboratory monitoring

Determining the extent of safety data collection needed in late stage premarket and postapproval clinical investigations, February 2012.