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Advisory Committee Presentation on Vioxx (Rofecoxib) Discussion on the meta analyses for cardiovascular risk assessment. Qian Li, Sc. D. Confirmed Serious CV Thrombotic Events Observed in VIGOR. 50 mg. Key Features of the Meta Analysis. Meta analysis of 25 studies
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Advisory Committee Presentation on Vioxx (Rofecoxib)Discussion on the meta analyses for cardiovascular risk assessment Qian Li, Sc. D.
Confirmed Serious CV Thrombotic Events Observed in VIGOR 50 mg VIOXX
Key Features of the Meta Analysis • Meta analysis of 25 studies • pooling different dose levels of rofecoxib (12.5, 25, and 50 mg) • pooling studies of different duration (4 weeks to one year) • combining different indication by stratified analyses (RA, OA, Alzheimer and back pain) VIOXX
Issue of the Meta Analysis • Does the meta analysis adequately address the role of rofecoxib 50 mg in relation to CV event? VIOXX
Concerns of the Meta Analysis 1. The risk ratios between rofecoxib & comparator may not be constant over time, • short term studies may not be able to demonstrate the treatment difference VIOXX
Concerns of the Meta Analysis 2. The risks may not be the same for different dose levels of rofecoxib, pooling may obscure the risk associated with a high dose group. Complication occurs if • different lengths of follow-up for different dose levels • different sample sizes for different dose levels VIOXX
Summary of Limitations • Risk ratio is not constant over time, • Not enough data over 6 month • Inadequate sample size outside VIGOR for rofecoxib 50 mg …... • Pooling different dose levels is problematic for an evaluation of rofecoxib 50 mg VIOXX
Conclusions • The meta analysis does not resolve the role of rofecoxib 50 mg in relation to the risk of CV events observed in the VIGOR trial. VIOXX
Three Comparisons • Rofecoxib vs. naproxen: • include indications of RA and OA • driven by the VIGOR trial • Rofecoxib vs. non-naproxen NSAIDs: • include only OA indications • Rofecoxib vs. placebo: • include ALZ and BP indication • driven by the ALZ tirals VIOXX
12.5 mg 25 mg 50 mg Sample Sizes for Studies at Least 6-month Duration Comparator VIOXX
The Assessment of CV Risk on Lower Doses of Rofecoxib • Did not show increased risk of CV events of low doses of rofecoxib in this meta analysis, • due to lack of power • due to special populations • It is not possible to draw conclusion based on this meta analysis. VIOXX
Preliminary Dose-response Assessmentprovided by sponsor including studies with duration longer than 6 months This assessment suggested a trend to increase risk with rofecoxib 50 mg. VIOXX