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Employing Complex Datasets for More Effective Decision-Making in Drug Development Fred Wilson Director, Clinical Imaging Experimental Medicine Imaging [email protected] Big Data, Multimodality & Dynamic Models in Biomedical Imaging Isaac Newton Insititute 9 th March 2016 Chris Page Manager, Support Analyst Digital Delivery and Imaging [email protected]
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Page 1: Employing Complex Datasets for More Effective Decision ... · i n bi otec hnol ogy i nnovation by Pi sano37; cr i tiques by Y oung38 and by H op ki ns et al .39, of t he vi ew t hat

Employing Complex Datasets for More Effective Decision-Making in Drug Development

Fred Wilson

Director, Clinical Imaging

Experimental Medicine Imaging

[email protected]

Big Data, Multimodality & Dynamic Models in Biomedical Imaging

Isaac Newton Insititute – 9th March 2016

Chris Page

Manager, Support Analyst

Digital Delivery and Imaging

[email protected]

Page 2: Employing Complex Datasets for More Effective Decision ... · i n bi otec hnol ogy i nnovation by Pi sano37; cr i tiques by Y oung38 and by H op ki ns et al .39, of t he vi ew t hat

Disclosures

– Both presenters:

– Current employees of GlaxoSmithKline and hold stock

– Fred Wilson:

– Previously a consultant to ECNP R&S, GlaxoSmithKline,

IPPEC, King’s College London, Lundbeck A/S, Mentis

Cura ehf and Pfizer Inc.

– Received travel expenses as a guest speaker on EEG

from Orion Pharma Ltd

– Previously an employee of Pfizer and held stock options

Page 3: Employing Complex Datasets for More Effective Decision ... · i n bi otec hnol ogy i nnovation by Pi sano37; cr i tiques by Y oung38 and by H op ki ns et al .39, of t he vi ew t hat

Outline

– Motivation:

– Attrition in the drug development pipeline

– What do we mean by complex data and decision-making?

– Improving decision-making in early drug development:

– The role of biomarkers – what do we need to measure?

– Example: electroencephalography (EEG) as a pharmacodynamic biomarker

– Quality control and data linkage in multi-site clinical studies:

– Improving on existing visual and other basic measures

– Extracting additional information from existing datasets

– Conclusions

Page 4: Employing Complex Datasets for More Effective Decision ... · i n bi otec hnol ogy i nnovation by Pi sano37; cr i tiques by Y oung38 and by H op ki ns et al .39, of t he vi ew t hat

4

Preclinical

Clinical development

Phase 1 - 2

Phase 3

FDA

EMEA

Market

Phase 4

Drug development – a lengthy and “risky” process

3 - 6 yrs 6 - 7 yrs 0.5-2yrs

5000 compounds

250 5 - 20 1 drug

approved

Page 5: Employing Complex Datasets for More Effective Decision ... · i n bi otec hnol ogy i nnovation by Pi sano37; cr i tiques by Y oung38 and by H op ki ns et al .39, of t he vi ew t hat

Motivation

– The situation is economically unsustainable

Nature Reviews | Drug Discovery

b Rate of decline over 10-year periods

Log (d

rugs

per billion U

S$)*

–1.0

–0.5

0

0.5

1.0

1.5

2.0

1950 1960 1970 1980 1990 2000 2010

c Adjusting for 5-year delay in spending impact

Num

ber

of dru

gs

per

billion U

S$ R

&D

spendin

g*

0

1

10

100

1950 1960 1970 1980 1990 2000 2010

a

Num

ber of d

rugs

per

billion U

S$ R

&D

spendin

g*

0.1

1.0

10

100

1950 1960 1970 1980 1990 2000 2010

Drugs per billion US$ R&D spending 5 years previously

Drugs per billion US$R&D spending

FDA tightensregulationpost-thalidomide

First wave ofbiotechnology-derived therapies

FDA clears backlogfollowing PDUFAregulations plus smallbolus of HIV drugs

The magnitude and duration of Eroom’s

Law also suggests that a lot of the things that

have been proposed to address the R&D pro-

ductivity problem are likely, at best, to have a

weak effect. Suppose that we found that it cost

80 times more in real terms to extract a tonne

of coal from the ground today than it did

60 years ago, despite improvements in mining

machinery and in the ability of geologists

to find coal deposits. We might expect coal

industry experts and executives to provide

explanations along the following lines: “The

opencast deposits have been exhausted and

the industry is left with thin seams that are

a long way below the ground in areas that

are prone to flooding and collapse.” Given

this analysis, people could probably agree

that continued investment would be justified

by the realistic prospect of either massive

improvements in mining technology or large

rises in fuel prices. If neither was likely, it

would make financial sense to do less digging.

However, readers of much of what has

been written about R&D productivity in

the drug industry might be left with the

impression that Eroom’s Law can simply be

reversed by strategies such as greater man-

agement attention to factors such as project

costs and speed of implementation26, by

reorganizing R&D structures into smaller

focused units in some cases27 or larger units

with superior economies of scale in others28,

by outsourcing to lower-cost countries26,

by adjusting management metrics and

introducing R&D ‘performance score-

cards’29, or by somehow making scientists

more ‘entrepreneurial’30,31. In our view, these

changes might help at the margins but it

feels as though most are not addressing

the core of the productivity problem.

There have been serious attempts to

describe the countervailing forces or to

understand which improvements have been

real and which have been illusory. However,

such publications have been relatively

rare. They include: the FDA’s ‘Critical Path

Initiative’23; a series of prescient papers by

Horrobin32–34, arguing that bottom-up

science has been a disappointing distraction;

an article by Ruffolo35 focused mainly on

regulatory and organizational barriers;

a history of the rise and fall of medical inno-

vation in the twentieth century by Le Fanu36;

an analysis of the organizational challenges

in biotechnology innovation by Pisano37;

critiques by Young38 and by Hopkins et al.39,

of the view that high-affinity binding of a

single target by a lead compound is the best

place from which to start the R&D process;

an analysis by Pammolli et al.19, looking at

changes in the mix of projects in ‘easy’ versus

‘difficult’ therapeutic areas; some broad-

ranging work by Munos24; as well as a

handful of other publications.

There is also a problem of scope. If we

compare the analyses from the FDA23,

Garnier27, Horrobin32–34, Ruffolo35, Le Fanu36,

Pisano37, Young38 and Pammolli et al.19, there

is limited overlap. In many cases, the differ-

ent sources blame none of the same counter-

vailing forces. This suggests that a more

integrated explanation is required.

Seeking such an explanation is important

because Eroom’s Law — if it holds — has

very unpleasant consequences. Indeed,

financial markets already appear to believe

in Eroom’s Law, or something similar to it,

and the impact is being seen in cost-cutting

measures implemented by major drug com-

panies. Drug stock prices indicate that inves-

tors expect the financial returns on current

and future R&D investments to be below

the cost of capital at an industry level40, and

Eroom’s Law in pharmaceutical R&D. a

b

c

REFS 24,86,87

(REF. 86) REF. 87

REFS 24,87

a

PERSPECTIVES

192 | M ARCH 2012 | VOLUM E 11 www.nature.com/reviews/drugdisc

© 2012 Macmillan Publishers Limited. All rights reserved

Scannell et al, Diagnosing the decline in pharmaceutical R&D efficiency, Nature Reviews Drug Discovery, 2012

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What do we mean by complex data and decision-

making?

– Most biological and clinical datasets are ‘complex’:

– Large numbers of data points

– Multiple sources of noise (random, biological, systematic)

– May not include large numbers of samples (so not true ‘big data’)

– ‘Decision-making’ requires data reduction to answer a

specific question:

– Typically requires a binary choice and/or reduction to a single

variable, for example:

– Is the drug binding to the target?

– Is the drug having a biological effect? How big an effect?

– Will this patient respond to the drug? By how much?

7

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Improving decision-making in early drug development

Page 9: Employing Complex Datasets for More Effective Decision ... · i n bi otec hnol ogy i nnovation by Pi sano37; cr i tiques by Y oung38 and by H op ki ns et al .39, of t he vi ew t hat

Parametric Sensitivity Analysis

Nature Reviews | Drug Discovery

p(TS): Phase II

p(TS): Phase III

Cost: lead optimization

Cycle time: Phase III

p(TS): Phase I

p(TS): submission to launch

Cycle time: Phase II

Cost: Phase II

Cost: Phase III

Cycle time: submission to launch

Cost: Phase I

p(TS): preclinical

Cost: hit-to-lead

p(TS): lead optimization

Cycle time: Phase I

Cost: preclinical

Cycle time: lead optimization

Cost: target-to-hit

Cycle time: preclinical

p(TS): hit-to-lead

Cost: submission to launch

Cycle time: hit-to-lead

p(TS): target-to-hit

Cycle time: target-to-hit

34%

70%

$10 million

2.5 years

54%

91%

2.5 years

$40 million

$150 million

1.5 years

$15 million

69%

$2.5 million

85%

1.5 years

$5 million

2 years

$1 million

1 year

75%

$40 million

1.5 years

80%

1 year

Capitalized cost per launch (US$ millions)

$1,200 $1,400 $1,600 $1,800 $2,000 $2,200 $2,400

Parameter Baseline value

25%

60%

$15

3.75

45%

80%

3.75

$60

$225

2.25

$22.5

60%

$3.75

75%

2.25

$7.5

3.0

$1.5

1.5

65%

$60

2.25

70%

1.5

50%

80%

$5

1.25

65%

100%

1.25

$20

$75

0.75

$7.5

80%

$1.25

95%

0.75

$2.5

1.0

$0.5

0.5

85%

$20

0.75

90%

0.5

determinant of overall R&D efficiency. In our baseline

model, Phase II p(TS) is 34% (that is, 66% of compounds

entering Phase II fail prior to Phase III). If Phase II attri-

tion increases to 75% (a p(TS) of only 25%), then the

cost per NME increases to $2.3 billion, or an increase of

29%. Conversely, if Phase II attrition decreases from 66%

to 50% (that is, a p(TS) of 50%), then the cost per NME

decreases by 25% to $1.33 billion. Similarly, our baseline

value of p(TS) for Phase III molecules is 70%; that is,

an attrition rate of 30%. If Phase III attrition increases

to 40%, then the cost per NME will increase by 16% to

$2.07 billion. Conversely, if Phase III attrition can be

reduced to 20% (80% p(TS)), then the cost per NME

will be reduced by 12% to $1.56 billion (FIG. 3).

Combining the impact of these increases or decreases

in Phase II and Phase III attrition illustrates the profound

effect of late-stage attrition on R&D efficiency. At the

higher end of the Phase II and III attrition rates discussed

above, the cost of an NME increases from our baseline

case by almost $0.9 billion to $2.7 billion, whereas at the

lower end of the above attrition rates for Phase II and III,

the cost per NME is reduced to $1.17 billion.

It is clear from our analyses that improving R&D effi-

ciency and productivity will depend strongly on reducing

Phase II and III attrition. Unfortunately, industry trends

suggest that both Phase II and III attrition are increas-

ing9,19–21, given both the more unprecedented nature of

the drug targets being pursued, as well as heightened

scrutiny and concerns about drug safety and the necessity

of demonstrating a highly desirable benefit-to-risk ratio

and health outcome for new medicines. However, main-

taining sufficient WIP while simultaneously reducing CT

and C will also be necessary to improve R&D efficiency.

We discuss these aspects first, before considering strategies

to reduce attrition in depth.

Work in process (WIP). We have already emphasized

the importance of having sufficient WIP at each phase

of drug discovery and development, and have suggested

that insufficient WIP, especially in discovery and the

early phases of clinical development has contributed

to the decline in NME approvals. To further illustrate

this point and again demonstrate the impact of Phase II

and Phase III attrition on Phase I WIP requirements, we

have carried out another sensitivity analysis using these

three parameters alone. FIG. 4 shows the impact of varying

Phase II and III attrition on the number of Phase I entries

per year required to launch a single NME annually. If the

p(TS) in Phase II and Phase III are 25% and 50% respec-

tively, approximately 16 compounds must enter Phase I

Figure 3 | R&D productivity model: parametric sensitivity analysis. This parametric sensitivity analysis is created

from an R&D model that calculates the capitalized cost per launch based on assumptions for the model’s parameters

(the probability of technical success (p(TS)), cost and cycle time, all by phase). When baseline values for each of the

parameters are applied, the model calculates a capitalized cost per launch of US$1,778 million (see Supplementary

information S2 (box) for details). This forms the spine of the sensitivity analysis (tornado diagram). The analysis varies each

of the parameters individually to a high and a low value (while holding all other parameters constant at their base value)

and calculates a capitalized cost per launch based on those new values for that varied parameter. In this analysis, the

values of the parameters are varied from 50% lower and 50% higher relative to the baseline value for cost and cycle time

and approximately plus or minus 10 percentage points for p(TS). Once cost per launch is calculated for the high and low

values of each parameter, the parameters are ordered from highest to lowest based on the relative magnitude of impact

on the overall cost per launch, and the swings in cost per launch are plotted on the graph. At the top of the graph are the

parameters that have the greatest effect on the cost per launch, with positive effect in blue (for example, reducing cost)

and negative effect in red. Parameters shown lower on the graph have a smaller effect on cost per launch.

ANALYSIS

NATURE REVIEWS | DRUG DISCOVERY VOLUM E 9 | M ARCH 2010 | 207

© 20 Macmillan Publishers Limited. All rights reserved10

Paul et al, How to improve R&D productivity: the pharmaceutical industry’s grand challenge, Nature Reviews Drug Discovery, 2010

Page 10: Employing Complex Datasets for More Effective Decision ... · i n bi otec hnol ogy i nnovation by Pi sano37; cr i tiques by Y oung38 and by H op ki ns et al .39, of t he vi ew t hat

De-risking Phase 2/3 using Biomarkers

Biomarker

Study

Phase 1

SD/MD

Combined

Phase 2a/2b

Phase 2a

(POC)

STOP

NORMAL GO

FAST GO

Proof of Pharmacology / PD measure

Proof of Mechanism and/or Efficacy Prediction

Model-based/mechanistic (in HVs)

Early Signal of Efficacy in Patients

Patient selection

Preclinical

Proof of Pharmacology / PD measure

Proof of Mechanism

Animal models of disease

* Biomarker study can be carried out in parallel

with the MD study to save time, if a single acute

dose design is used; some techniques such as

EEG can potentially be integrated in the Phase 1

(SD or MD) studies;

Biomarker

Study*

Wilson, F.J. & Danjou P., 2015 Early Decision-Making in Drug Development: The Potential Role of

Pharmaco-EEG and Pharmaco-Sleep, Neuropsychobiology, 72, pp.188-194.

Page 11: Employing Complex Datasets for More Effective Decision ... · i n bi otec hnol ogy i nnovation by Pi sano37; cr i tiques by Y oung38 and by H op ki ns et al .39, of t he vi ew t hat

Fundamental PK-PD Principles

– Recent review of 44 Phase 2 drug development projects at Pfizer

– Examined based on 3 principles:

PILLAR 1: Exposure at the target site of action

PILLAR 2: Binding to the pharmacological target

PILLAR 3: Expression of pharmacology

– Summarised onto two axes:

EXPOSURE CONFIDENCE: Based on Pillars 1 and 2

PHARMACOLOGY CONFIDENCE: Based on Pillars 2 and 3

Morgan et al, Can the flow of medicines be improved? Fundamental pharmacokinetic and pharmacological principles toward improving Phase II survival, Drug Discovery Today, 2012

Page 12: Employing Complex Datasets for More Effective Decision ... · i n bi otec hnol ogy i nnovation by Pi sano37; cr i tiques by Y oung38 and by H op ki ns et al .39, of t he vi ew t hat

Fundamental PK-PD Principles

17% POC success

17% Phase 3 transition

86% POC success

57% Phase 3 transition

0% PoC success 0% PoC success

Morgan et al, Can the flow of medicines be improved? Fundamental pharmacokinetic and pharmacological principles toward improving Phase II survival, Drug Discovery Today, 2012

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Involves large neuronal populations that include all major neurotransmitter systems

John, E Roy; Prichep, Leslie S, The relevance of QEEG to the evaluation of behavioral disorders

and pharmacological interventions, Clinical EEG and Neuroscience, 37(2), pp. 135-43, 2006

EEG – a window onto brain function

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Status of pEEG as a PD biomarker

– Lots of historical issues with unclear results from pEEG

– Propose a new framework for when to use pEEG as a PD biomarker:

– Two simple criteria:

– Preclinical experiments produce a robust result

– We expect this to translate (based on best current knowledge)

– Clinical study should be designed to test for the expected effect, with other

pEEG measures as secondary endpoints

Wilson, F.J. et al., 2014. Can pharmaco-electroencephalography help improve survival of central

nervous system drugs in early clinical development? Drug discovery today, 19(3), pp.282–288.

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Classical Quantitative EEG Analysis

– Generate frequency spectrum of signal (e.g. using Short-Term Fast Fourier

Transform)

– Split frequencies into bands (Delta, Theta, Alpha, Beta, Gamma)

– Evaluate required endpoints:

– Total and relative spectral power in each band

– Power ratios

– Coherence between different regions in each frequency band

– Other parameters e.g. peak alpha frequency

0.00000

0.00005

0.00010

0.00015

0.00020

0.00025

0.00030

0 10 20 30 40

Po

we

r

Frequency

Delta

Theta

Alpha

Beta

Gamma

Fourier

Transform

Page 16: Employing Complex Datasets for More Effective Decision ... · i n bi otec hnol ogy i nnovation by Pi sano37; cr i tiques by Y oung38 and by H op ki ns et al .39, of t he vi ew t hat

Famous Example - Benzodiazepines

– Complex PK-PD modelling with EEG works well e.g.

Greenblatt DJ, von Moltke, LL, Ehrenberg, BL, Harmatz JS, Corbett KE, Wallace DW, Shader RI 2000 Kinetics

and dynamics of lorazepam during and after continuous intravenous infusion Crit. Care Med. 28 2750-7

following values: apparent half-lives of distribu-

tion and elimination (t1/2 and t1/2 , respec-

tively), elimination rateconstant (ke /k21),

clearance(CL V1ke), total volumeof distribu-

tion using the area method (Vd CL/ ), and

predicted steady-state plasma concentration of

lorazepam (Css Q/CL).

Examination of plots of pharmacodynamic

electroencephalographic effect vs. plasma

lorazepam concentration (E vs. C) indicated

counterclockwise hysteresis, consistent with a

delay in equilibration of lorazepam between

plasma and the site of pharmacodynamic ac-

tion in brain. This has been described in pre-

vious clinical and experimental studies of

lorazepam (9, 12–15, 34). Accordingly, the re-

lationship was modified to incorporate a dis-

tinct “effect-site,” at which the hypothetical

lorazepam concentration is CE. The apparent

rate constant for drug disappearance from the

effect compartment is kEO; this rate constant

determines the apparent half-life of drug

equilibration (t1/kEO) between plasma and ef-

fect site (Fig. 1) (31, 32, 34–36). Under these

assumptions, the relation of E to CE was pos-

tulated to beconsistent with a “Sigmoid Emax”

model, as follows:

EEmax CE kEO

A

EC50A CE kEO

A (2)

In Equation 2, Emax is the maximum phar-

macodynamic effect, EC50 is the value of CE

corresponding to 50% of Emax, and A is an ex-

ponent (the Hill coefficient). This represents a

previously described mathematical relationship

(31, 32) modified to contain an implicit conver-

sion of CE values such that CEkEOhas units of

concentration analogous to those in the central

compartment.

The relation of CE to time (t) was assumed

to be consistent with the following equation:

CE

D

V1

k21

kEO

e t

k21

kEO

e t

k21 kEO

kEO kEO

e kEOt

Q

V1

k21

kEO

1 e T e t

k21

kEO

1 e T e t

k21 kEO

kEO kEO kEO

1 ekEOT e kEO t

(3)

In Equation 3, T t when t is 4 hrs, and

T 4 when t is 4 hrs. D and Q werefixed as

described for Equation 1, and the values of ,

, k21, and V1 were fixed as determined for

that subject from nonlinear regression using

Equation 1.

Using Equations 2 and 3 simultaneously,

data points (E and t) were analyzed by nonlin-

ear regression. Iterated variables were Emax,

EC50, A, and kEO.

Data were analyzed for each subject indi-

vidually. We also determined an aggregate (or

composite) data set, formed by calculation of

average plasma lorazepam concentrations and

electroencephalographic changes across all

subjects at corresponding times. The single

data set formed by aggregation was analyzed

as described in this section.

RESULTS

All subjects reported sedative effectsassociated with lorazepam administra-tion. There were no adverse reactions oruntoward cardiovascular or respiratoryeffects.

Plasma lorazepam concentrationswere consistent with Equation 1 in eightof the nine subjects, based on visual in-spection of the data (Fig. 2); in one sub-ject, adistribution phase wasnot evident,and data were analyzed using a one-compartment model. Kinetic variables(Table 1) were similar to those reportedin previous single-dose studies of loraz-epam pharmacokinetics (9, 20–26). Thebolus-plus-infusion scheme rapidly pro-duced mean plasma lorazepam concen-trations in the range of 18–19 ng/mL,values close to the mean ( SEM) pre-dicted Css value of 24.1 ( 1.6) ng/mL.

The no-treatment trial, which evalu-ated possible time-dependent electroen-cephalographic changes, produced onlysmall changes over baseline in electroen-cephalographic activity; all of thesechanges were in the negative direction(Fig. 3). Thelorazepam infusion trial pro-duced significant increases in electroen-cephalographic activity throughout the24-hr duration of the study (Fig. 3). Themaximum changeover baseline wasmea-sured 0.5 hr after initiation of lorazepamdosage, whereas the maximum plasmaconcentration wasmeasured immediatelyafter the loading dose (Fig. 4). Electroen-cephalographic effects of lorazepam di-minished somewhat between 1 and 4 hrsafter the start of the infusion, despiteessentially constant plasma concentra-tions; however, these changes in electro-encephalographic amplitude over timewere not significant.

Plots of plasma lorazepam concentra-tion vs. electroencephalographic changeindicated counterclockwise hysteresis inseven of the nine subjects (Fig. 5). The

Figure 1. Schematic representation of a two-compartment pharmacokinetic model, modified by incorpo-

ration of ahypothetical effect-site distinct from thecentral compartment. The “k ” designations represent

first-order rate constants having units of reciprocal time. k12 and k21 are intercompartmental distribution

rate constants. ke is the first-order elimination rate constant. kEO is the rate constant for drug disappear-

ance from the hypothetical effect-site. k1E is the rate constant for drug entry into the hypothetical

effect-site; it can beshown that thisquantity ultimately doesnot influence thecomputations (31, 32). I.V.,

intravenous.

2752 Crit Care Med 2000 Vol. 28, No. 8

following values: apparent half-lives of distribu-

tion and elimination (t1/2 and t1/2 , respec-

tively), elimination rate constant (ke /k21),

clearance (CL V1ke), total volume of distribu-

tion using the area method (Vd CL/ ), and

predicted steady-state plasma concentration of

lorazepam (Css Q/CL).

Examination of plots of pharmacodynamic

electroencephalographic effect vs. plasma

lorazepam concentration (E vs. C) indicated

counterclockwise hysteresis, consistent with a

delay in equilibration of lorazepam between

plasma and the site of pharmacodynamic ac-

tion in brain. This has been described in pre-

vious clinical and experimental studies of

lorazepam (9, 12–15, 34). Accordingly, the re-

lationship was modified to incorporate a dis-

tinct “effect-site,” at which the hypothetical

lorazepam concentration is CE. The apparent

rate constant for drug disappearance from the

effect compartment is kEO; this rate constant

determines the apparent half-life of drug

equilibration (t1/kEO) between plasma and ef-

fect site (Fig. 1) (31, 32, 34–36). Under these

assumptions, the relation of E to CE was pos-

tulated to be consistent with a “Sigmoid Emax”

model, as follows:

EEmax CE kEO

A

EC50A CE kEO

A (2)

In Equation 2, Emax is the maximum phar-

macodynamic effect, EC50 is the value of CE

corresponding to 50% of Emax, and A is an ex-

ponent (the Hill coefficient). This represents a

previously described mathematical relationship

(31, 32) modified to contain an implicit conver-

sion of CE values such that CEkEOhas units of

concentration analogous to those in the central

compartment.

The relation of CE to time (t) was assumed

to be consistent with the following equation:

CE

D

V1

k21

kEO

e t

k21

kEO

e t

k21 kEO

kEO kEO

e kEOt

Q

V1

k21

kEO

1 e T e t

k21

kEO

1 e T e t

k21 kEO

kEO kEO kEO

1 ekEOT e kEO t

(3)

In Equation 3, T t when t is 4 hrs, and

T 4 when t is 4 hrs. D and Q were fixed as

described for Equation 1, and the values of ,

, k21, and V1 were fixed as determined for

that subject from nonlinear regression using

Equation 1.

Using Equations 2 and 3 simultaneously,

data points (E and t) were analyzed by nonlin-

ear regression. Iterated variables were Emax,

EC50, A, and kEO.

Data were analyzed for each subject indi-

vidually. We also determined an aggregate (or

composite) data set, formed by calculation of

average plasma lorazepam concentrations and

electroencephalographic changes across all

subjects at corresponding times. The single

data set formed by aggregation was analyzed

as described in this section.

RESULTS

All subjects reported sedative effectsassociated with lorazepam administra-tion. There were no adverse reactions oruntoward cardiovascular or respiratoryeffects.

Plasma lorazepam concentrat ionswere consistent with Equation 1 in eightof the nine subjects, based on visual in-spection of the data (Fig. 2); in one sub-ject, a distribution phase was not evident,and data were analyzed using a one-compartment model. Kinetic variables(Table 1) were similar to those reportedin previous single-dose studies of loraz-epam pharmacokinetics (9, 20–26). Thebolus-plus-infusion scheme rapidly pro-duced mean plasma lorazepam concen-trations in the range of 18–19 ng/mL,values close to the mean ( SEM) pre-dicted Css value of 24.1 ( 1.6) ng/mL.

The no-treatment trial, which evalu-ated possible time-dependent electroen-cephalographic changes, produced onlysmall changes over baseline in electroen-cephalographic activity; all of thesechanges were in the negative direction(Fig. 3). The lorazepam infusion trial pro-duced significant increases in electroen-cephalographic activity throughout the24-hr duration of the study (Fig. 3). Themaximum change over baseline was mea-sured 0.5 hr after initiation of lorazepamdosage, whereas the maximum plasmaconcentration wasmeasured immediatelyafter the loading dose (Fig. 4). Electroen-cephalographic effects of lorazepam di-minished somewhat between 1 and 4 hrsafter the start of the infusion, despiteessentially constant plasma concentra-tions; however, these changes in electro-encephalographic amplitude over timewere not significant.

Plots of plasma lorazepam concentra-tion vs. electroencephalographic changeindicated counterclockwise hysteresis inseven of the nine subjects (Fig. 5). The

Figure 1. Schematic representation of a two-compartment pharmacokinetic model, modified by incorpo-

ration of a hypothetical effect-site distinct from the central compartment. The “k ” designations represent

first-order rate constants having units of reciprocal time. k12 and k21 are intercompartmental distribution

rate constants. ke is the first-order elimination rate constant. kEO is the rate constant for drug disappear-

ance from the hypothetical effect-site. k1E is the rate constant for drug entry into the hypothetical

effect-site; it can beshown that this quantity ultimately doesnot influence the computations (31, 32). I.V.,

intravenous.

2752 Crit Care Med 2000 Vol. 28, No. 8

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The Problems with Classical Analysis

– Numerous potential endpoints (100s or 1000s):

– 19 or more electrode positions

– 5 frequency bands (more if subdivided)

– Absolute and relative power values

– Power ratios

– Coherence measures (by scalp region and band)

– Individual endpoints lack specificity

– Readout often dependent on post hoc interpretation

– Impossible to define criteria a priori to enable clear decisions

17

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Generalised Semi-linear Canonical Correlation Analysis

(GSLCCA)

– Method developed to enhance utility of EEG as a PD biomarker by using

data from the:

– Whole spectrum (without dividing into bands)

– Entire recording duration

– All electrodes

– To provide:

– Interpretable mechanistic information

– A PD measure

– Assuming:

– A PD profile of a known form (i.e. a given equation with unknown parameters)

Brain, P., Strimenopoulou, F. & Ivarsson, M., 2012. Generalized Semilinear Canonical Correlation Analysis Applied to the

Analysis of Electroencephalogram (EEG) Data. Statistics in Biopharmaceutical Research, 4(2), pp.149–161.

Brain et al, 2014. Extracting drug mechanism and pharmacodynamic information from clinical electroencephalography data

using generalised semi-linear canonical correlation analysis. Physiological Measurement, 35(12), pp. 2459–2474.

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GSLCCA - Principle

0 10

0.00

5

-0.02

2520

-0.04

-0.06

0.08

0.04

15

0.06

0.02

3530

! (0,...,0) v FrequencyTRANSPOSE(Mean)*Alpha v Frequency

Power Spectra at time t

0 . 0 0 0 0 0

0 . 0 0 0 0 5

0 . 0 0 0 1 0

0 . 0 0 0 1 5

0 . 0 0 0 2 0

0 . 0 0 0 2 5

0 . 0 0 0 3 0

0 5 1 0 15 2 0 2 5 3 0 3 5 4 0

Frequency y

Po

we

r

X

Measured PD Response at time t

PK/PD Model

012345678

0 20 40 60 80 100

Time

Resp

on

se

XX X

(c) Model PD response profile

012345678

0 20 40 60 80 100

Time

Res

po

nse

X

(a) Power spectrum at time t

Frequency

We

igh

t

(b) Signature obtained using GSLCCA

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GSLCCA – Example Results

Mean t50 = 3.04 ± 0.88 minutes

Clinical study with remifentanil

Brain et al, 2014. Extracting drug mechanism and pharmacodynamic

information from clinical electroencephalography data using generalised

semi-linear canonical correlation analysis. Physiological Measurement,

35(12), pp. 2459–2474.

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Quality control and data linkage in multi-site clinical studies

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Linking Imaging to Other Clinical Endpoints

Goal of stratified medicine is to allow a clinician to determine the optimal therapy or

combination of therapies for an individual at the earliest possible stage

– How can this be determined based on initial presentation of disease?

– Integrated analysis of genomic and other data

– Imaging is primary endpoint in many clinical studies

– Incorporating imaging data to analysis is challenging

– Raw data are essentially large volumes of pixel intensities

– Requires semantically-rich descriptors to correlate with other data sources

– Essentially a problem of knowledge extraction from image volumes

– Not a classical Big Data problem

– Relatively small number of samples (subject-visits)

– Each sample is very well-characterised

Strategy for “Big Data” and Stratified Medicine

22

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Registration-Path Imaging Studies

– Safety and efficacy

– Established endpoints

– Large(ish) sample populations

– Data acquired globally in clinical radiology departments

– Local and centralised independent radiological review

– Regulated

– Conservative

Multisite and standardised

23

Acquire

Quality

Control Analyse Archive Deidentify

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Patient’s Name John Doe

Patient ID BW129814

Patient’s Sex Male

Study Date 12-Nov-2010

Patient's Birth Date 05-Apr-1960

Modality CT

Referring Physician Dave Smith

Patient’s Name 001234

Patient ID 001234

Patient’s Sex Male

Study Date 05-Dec-2007

Patient's Birth Date 30-Jun-1960

Modality CT

Referring Physician

Clinical Imaging Data Digital Imaging and Communications in Medicine (DICOM)

24

Image

Meta

data

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Sensitive Personally Identifiable Information Pixel deidentification

25

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Response Evaluation Criteria in Solid Tumours (RECIST) Standard objective measures of response to therapy

http://www.recist.com/recist-in-practice/

26

Follow-on

Baseline

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QC and Analysis Pipeline

– Algorithms should be general

– Validation overhead obviates study-specific software

– Broad applicability across TAs

– Outputs should include confidence estimate

– Need to be able to identify false-positives

– Challenges

– Statistical bias: value of comparing data between studies?

– Variations in acquisition (multisite)

Opportunities for automation

27

Classify

Dataset

Detect

Features

Quantify

Features Linkage

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Classification and Automated QC

– Characterise

– Modality

– Anatomical region

– Contrasting agent

– Gender

– Age

– QC

– Correct person

– Missing slices

– Feature detection

– Artefacts

– Anomalies

Randomised Decision Forests

Courtesy Ben Glocker

Glocker et al, Vertebrae Localization in Pathological Spine CT via Dense Classification

from Sparse Annotations, in MICCAI, September 2013

Criminisi et al, Regression Forests for Efficient Anatomy Detection and Localization in

Computed Tomography Scans, in Medical Image Analysis (MedIA), Elsevier, 2013

Criminisi et al, A Discriminative-Generative Model for Detecting Intravenous Contrast in

CT Images, in MICCAI, September 2011.

28

Liver Right

Kidney

Right

Lung

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Radiomics Detailed quantitative biomarkers are better predictors of survival?

Aerts et al, Decoding tumour phenotype by noninvasive imaging using a quantitative radiomics approach. Nat Commun 2014 5 4006

29

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– A scalable analytics platform for GSK R&D based on Hadoop infrastructure and supporting

analytics tools

– Facilitates study of information brought together from multiple domains to uncover unique

and actionable insights

Integrative Data Analytics at GSK Using technology to make data more accessible

30

Analytics

ready data

Internal

and

external

source

data

BI and

analytics

tools

Caching

and

navigation

Data

extraction

Raw

ingested

data

Intelligent

curation

R&D

scientists

and

analysts

High-performance compute

Security, metadata, change management, governance

Informatics

and

computation

teams

Systems administrators

Data

engineers

Data

curators

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Project CRAWL

– Reporting of post-market adverse events

relies on patient following formal process

– CRAWL extends GSK’s safety activities

to social media communications

– Cloud-based validated system to monitor

social media for drug safety in real time

– Standardises colloquial language into

medical terminology

– Removes PII and unwanted noise

– Highlights the questions being asked

– Identifies potential supply chain concerns

(adulteration, counterfeiting)

– Safety listening lab monitors data

Contextualisation of Real-World Drug-Use through Social Listening

31

http://epidemico.com/2015/04/22/2015-bio-it-world-best-practices-award-clinical-health-

it-winner-project-crawl/

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Conclusions

– Complex datasets include not only ‘Google style’ big data

(i.e. billions of samples) but also other rich datasets (i.e.

many data points but not necessarily large numbers of

samples)

– The pharmaceutical industry still relies on very simple

analysis methods

– There is significant scope for improvement!

32


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