the vioxx withdrawal what happened? john a. baron dartmouth medical school for the approve...
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The Vioxx Withdrawal
What Happened?
John A. Baron Dartmouth Medical School
for the APPROVe Investigators
Vioxx
A Recent Quote
The licensing of Vioxx and its continued use …. have been public-health catastrophes.
(Lancet, Nov 5)
COX-2 Inhibitors
What are They? Should we Care?
Cyclooxygenase & Prostaglandins
Membrane phospholipids
Arachidonate
PGH2
PGE2 PGF2 PGD2 PGI2 TXA2
PGG2COX
ProstanoidsCell Signaling Molecules
Peroxidase
Isomerase
Phospholipase A2
PGG2
PGH2
Prostaglandins Thromboxanes
Angiogenesis
Apoptosis
Vascular ReactivityInvasiveness
Inflammation
Platelet function
NSAIDs
CO
X
Phospholipids, Arachidonic Acid
Cyclooxygenase
2 Isoforms
Cox-1 Cox-2 consitutive induciblehouse-keeping inflammation, cancer
Cox-2 w/o Cox-1 inhibition may offer:
Anti-inflammatory effects Cancer prevention
AND Protection of stomach No bleeding
Cox-2 w/o Cox-1 inhibition may offer:
Anti-inflammatory effects Cancer prevention
AND Protection of stomach No bleeding
Vioxx
Early History
• Vioxx (Rofecoxib) released in 1999• An “early” COX-2 inhibitor
more selective than celecoxib• Premise of COX-2 inhibitors:
greater safety than traditional NSAIDs at least equal efficacy
Thrombotic CV Events: the VIGOR Study
Overall RR: 2.38 (1.39, 4.00)
Overall RR 1.09 (0.69,1.73)Overall RR 1.09 (0.69,1.73)
Thrombotic CV Events: Phase II OA
Cardiovascular Background
Summary
In randomized trials prior to APPROVe cardiovascular risk for rofecoxib was:
• Higher than for naproxen• Similar to non-naproxen NSAIDs• Similar to Placebo
(limited data beyond 2 years)
Summary
In randomized trials prior to APPROVe cardiovascular risk for rofecoxib was:
• Higher than for naproxen• Similar to non-naproxen NSAIDs• Similar to Placebo
(limited data beyond 2 years)
APPROVe Study
(Adenomatous Polyp Prevention with VIOXX)
Standard Adenoma Prevention Study
Subjects with recent adenoma3-year adenoma endpoint1-year research colonoscopyRofecoxib 25 mg vs. placebo107(!) sites, 39 in U.S.
(Adenomatous Polyp Prevention with VIOXX)
Standard Adenoma Prevention Study
Subjects with recent adenoma3-year adenoma endpoint1-year research colonoscopyRofecoxib 25 mg vs. placebo107(!) sites, 39 in U.S.
APPROVe Study
Study overseen by
External Steering CommitteeExternal Safety Monitoring Board (ESMB)
Adjudication of Serious CV Events
Prespecified Protocol for CV effects
Study overseen by
External Steering CommitteeExternal Safety Monitoring Board (ESMB)
Adjudication of Serious CV Events
Prespecified Protocol for CV effects
APPROVe Study Design
Study Visit Study Visit
RandomizationRandomizationPlaceboPlacebo (N~1214) (N~1214)
Rofecoxib 25 mgRofecoxib 25 mg (N~1214) (N~1214)
*non-study, within 3 months prior to screening*non-study, within 3 months prior to screening
36361212Month -4.5Month -4.5 00-1.5-1.5
Colo*Colo* ColoColo ColoColo
2424
APPROVe Eligibility
Inclusion Criteria ≥ 40 years oldhistologically confirmed large bowel adenomaPrior MI, PTCA, CABG OK if > 1year prior T0
Exclusion Criteria Uncontrolled hypertension (>165/95 mm Hg),
angina at rest or minimal activity, CHF at rest
Inclusion Criteria ≥ 40 years oldhistologically confirmed large bowel adenomaPrior MI, PTCA, CABG OK if > 1year prior T0
Exclusion Criteria Uncontrolled hypertension (>165/95 mm Hg),
angina at rest or minimal activity, CHF at rest
Male (%)
Mean age
Aspirin use (%)
Hypertension (%)
CV risk* (%)
Current Smoker (%)
Male (%)
Mean age
Aspirin use (%)
Hypertension (%)
CV risk* (%)
Current Smoker (%)
62
59 years
19
36
29
22
62
59 years
19
36
29
22
62
59 years
18
34
26
22
62
59 years
18
34
26
22
* CV hx, or ≥2 of: hx of DM, cholesterol, HTN, smoker* CV hx, or ≥2 of: hx of DM, cholesterol, HTN, smoker
RofecoxibN=1287
RofecoxibN=1287
PlaceboN=1299PlaceboN=1299
APPROVeBaseline Characteristics
APPROVe CV Events, as of 8/16/2004
118 Investigator-reported events
70 Confirmed Thrombotic EventsMI, Unstable Angina, Sudden DeathStroke, TIADVT, PE, Arterial Thrombosis
49 Confirmed APTC events*
Death: CV or unknown cause MIStroke
118 Investigator-reported events
70 Confirmed Thrombotic EventsMI, Unstable Angina, Sudden DeathStroke, TIADVT, PE, Arterial Thrombosis
49 Confirmed APTC events*
Death: CV or unknown cause MIStroke
*APTC = Antiplatelet Trialists’ Collaboration BMJ. 1994*APTC = Antiplatelet Trialists’ Collaboration BMJ. 1994
APPROVe CV Events
PlaceboN=1299PlaceboN=1299
RofecoxibN=1287
RofecoxibN=1287
Relative Risk (95%CI)
Relative Risk (95%CI)
0.75(25/3315)
0.48 (16/3322)
0.75(25/3315)
0.48 (16/3322)
1.48 (45/3041)
1.08 (33/3053)
1.48 (45/3041)
1.08 (33/3053)
Thrombotic(70 Events)
APTC(49 Events)
Thrombotic(70 Events)
APTC(49 Events)
1.96 (1.20, 3.19)
2.25 (1.24, 4.08)
1.96 (1.20, 3.19)
2.25 (1.24, 4.08)
Rate per 100 (N/ P-Yrs)
RR for CHF/PE/Cardiac Failure: 4.29 (1.43, 12.82)RR for CHF/PE/Cardiac Failure: 4.29 (1.43, 12.82)
APPROVe Confirmed Thrombotic Events
Cardiac Events
Cerebrovascular Events
Peripheral Vascular Events
Placebo (N=1299) Rofecoxib (N=1287)
11
7
7
30
15
3
APPROVe Confirmed Thrombotic Endpoints
Overall RR: 1.96 (1.20, 3.19)
Thrombotic CV Events
Overall RR 1.01 (0.67,1.53)
Alzheimer’s Disease Studies
APPROVe Thrombotic Events
Subgroup analyses
Age • Aspirin useHypertension • Cigarette
smokingDiabetes • CV risk*Hypercholesterolemia
No treatment by Subgroup Interactions
Subgroup analyses
Age • Aspirin useHypertension • Cigarette
smokingDiabetes • CV risk*Hypercholesterolemia
No treatment by Subgroup Interactions
*CV hx, or ≥2 of: hx of DM, cholesterol, HTN, smoker*CV hx, or ≥2 of: hx of DM, cholesterol, HTN, smoker
APPROVe: Blood Pressure
Preliminary analyses not suggestive of a relationship between blood pressure rise and risk
Preliminary analyses not suggestive of a relationship between blood pressure rise and risk
APPROVe CV Events
Summary risk of thrombotic CV events
after 18 months of Tx
1st 18 months consistent with prior placebo-controlled and nonnaproxen controlled data
On the basis of these data, VIOXX was withdrawn
Summary risk of thrombotic CV events
after 18 months of Tx
1st 18 months consistent with prior placebo-controlled and nonnaproxen controlled data
On the basis of these data, VIOXX was withdrawn
APPROVe: The Future
Mechanism of CV toxicity uncertainAnalyses ongoingPatients will be followed for one year per
protocol
Adenoma data will be analyzedStudy within 3 months of completion anyway
~75% of subjects had completed treatment
Mechanism of CV toxicity uncertainAnalyses ongoingPatients will be followed for one year per
protocol
Adenoma data will be analyzedStudy within 3 months of completion anyway
~75% of subjects had completed treatment
APPROVe Research Team
John Baron†, Robert S Bresalier††, Robert Sandler‡, Robert Riddell§, Angel Lanas║, Dion Morton¶, Alise Reicin#, Bettina Oxenius#, Kevin Horgan#, Hui Quan#
†Dartmouth Medical School ††University of Texas MD Anderson Cancer Center; ‡University of North Carolina at Chapel Hill; §Mount Sinai Hospital, Toronto; ║University Clinic Hospital, Zaragoza, Spain; ¶University of Birmingham, UK; #Merck Research Laboratories
John Baron†, Robert S Bresalier††, Robert Sandler‡, Robert Riddell§, Angel Lanas║, Dion Morton¶, Alise Reicin#, Bettina Oxenius#, Kevin Horgan#, Hui Quan#
†Dartmouth Medical School ††University of Texas MD Anderson Cancer Center; ‡University of North Carolina at Chapel Hill; §Mount Sinai Hospital, Toronto; ║University Clinic Hospital, Zaragoza, Spain; ¶University of Birmingham, UK; #Merck Research Laboratories
MI (not Total CVD)
Year19971998
1999
2000
2002
# Events
1640
64
# Patients
519313,269
21,432
Combined RR = 2.24 (1.24-4.02
Cumulative Metaanalysis
Juni et al,2004Juni et al,2004
VIGOR Study
Naproxen & MI RiskObservational Data
Combined RR (0.86 0.75-0.99)
Jick (2000)
Rahme (2002)
Ray (2002)
Ray (2002)
Schlienger (2002)
Solomon (2002)
Watson (2002)
Mamdani (2003)
Kimmel (2004)
Graham (2004)
Garcia Rdoriguez (2004)Juni et al, 2004Juni et al, 2004
COX-2 Inhibitors & CVD
What are the Possible Mechanisms?
Aspirin
COX-1
Thromboxane
Prostacyclin Thromboxane
COX-2 Inhibition
Decreased CV eventsDecreased CV events
Prostacyclin
Increased CV events
COX-2
Atherosclerosis
An Inflammatory Process
• Cox-2 over expressed in atheroma• Cox-2 inhibitors might be beneficial??
NSAIDs and Blood Pressure
Frishman, Am J Cardiol, 2002Frishman, Am J Cardiol, 2002
Baseline mean = 136 mm Hg
Cha
nge
from
bas
elin
e (m
m H
g)
Baseline mean = 136 mm Hg
Baseline mean = 81 mm HgFrishman, 2002Frishman, 2002
NSAIDs & GFR
Harris, Am J Cardiol, 2002Harris, Am J Cardiol, 2002
NSAIDs and CHF
“An Underrecognized Public Health Problem”
• NSAIDs can CHF • Stronger effect with Hx of CVD (Especially drugs w/ long half life)
Heerdink et al, Arch Intern Med, 1998 Page & Henry, Arch Intern Med, 2000 Feenstra et al, Arch Intern Med, 2002
COX-2 & Cardiovascular Disease
Background
• COX-2 vascular prostacyclin• COX-2 inflammation
Net effect on atherosclerotic disease?
• COX-2 involved in renal tubular function• COX-2 inhibition may lead to: fluid retention
HTN
Vioxx
Summary
• Increases in CVD• Probably delayed• Probably rare
Summary
• Increases in CVD• Probably delayed• Probably rare
Published commentary uninformedPublished commentary uninformed