Articles Presented. Journal Presentation. Dr Albert Lo. Dr Albert Lo

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1 * This presentation is prepared by the author in one s personal capacity for the purpose of academic exchange and does not represent the views of his/her organisations on the topic discussed. Journal Presentation Grand Round in Administrative Medicine June Articles Presented "The Cox- Inhibitor Saga". Silverstein FE. Faich G. Goldstein JL. et al. Gastrointestinal toxicity with celecoxib vs nonsteroidal anti-inflammatory drugs for osteoarthritis and rheumatoid arthritis: the CLASS study: A randomized controlled trial. Long-term Arthritis Safety Study JAMA. 8():7-, Sep.. Lichtenstein DR. Wolfe MM. COX--Selective. JAMA. 8():97-99, Sep.. Hrachovec JB, Mora M. Letter to the Editor: Reporting of -Month vs - Month Data in a Clinical Trial of JAMA, 8(9); 98, Nov.. Juni P, Rutjes AWS, Dieppe PA. Are selective COX- inhibitors superior to traditional? BMJ ; : Cell membrane Phospholipids Most Arachidonic acid Prostagladins isoforms COX- Homeostatic produces functions homeostatic Inflammation gastric PGs acid production pain COX- Gastric produces musculature inflammatory blood flow PGs maintain GI muscosal integrity Cyclo oxygenase (COX) Relative COX- Selectivity (log ) - - Least Rofecoxib (vioxx) (celebrex) Diclofenac (Voltaren) Ibuprofen Naproxen Aspirin Ketorolac Short-term RCTs showed fewer ulcer cases in patients treated with COX- inhibitors (9-%) than non-selective NSAIDS (- %) Comparison of upper gastrointestinal toxicity of rofecoxib and naproxen in patients with rheumatoid arthritis VIGOR study FDA approved usage of and Rofecoxib in 999 NEJM Nov,

2 7 Gastrointestinal toxicity with vs for osteoarthritis and rheumatoid arthritis CLASS - longterm arthritis safety study JAMA September, 8 Study objective : Design : Setting : Participants : To determine whether is associated with a lower incidence of significant upper GI and toxic effects and other adverse effects compared with conventional Double-blind RCT 8 clinics in USA and Canada 89 patients with OA or RA Interventions : Main outcome measures : 987 received mg bd 98 received Ibuprofen 8mg tds 99 received Diclofenac 7mg bd Symptomatic upper GI ulcers and ulcer complications (bleeding, perforation and obstruction) and other adverse effects during the -m treatment period Special features of the study Dose of -x maximum FDA-approved effective dosages for RA and OA % of patients in both study and control arms took low dose aspirin 9 Results () 89 patients Significantly more Ibuprofen Diclofenac patients withdrew for = 98 adverse effects or lack of therapeutic efficacy withdrawn 78 withdrawn 7 completed 97 completed Results () No significant differences in baseline patient characteristics Age Gender Race Disease category and duration H. pylori infection Tobacco and alcohol use Concurrent medications

3 Result () No. of cases adjudicated No. of cases meeting definition of ulcer complication (n= 987) NSAID (n=98) 9 P<. P=NS Result () - All Patients / P=.9 /8 / P=. 9/8 Result () - Patients Not Taking Aspirin / P=. / / P=. / Result () - Patients Taking Aspirin /98 P=.9 /8 /98 P=.9 7/8 Result (7) - Other adverse effects Overall incidence of GI symptoms Liver enzymes Bleeding related disorders Creatinine Significantly lower in group Conclusion, at dosages greater than those indicated clinically, was associated with a lower incidence of symptomatic ulcers and ulcer complications combined, as well as other clinically important toxic effects, compared with NSAID at standard dosages 7 8

4 9 COX- Selective New or Improved? The results. provide promising data to suggest that celecoxib and possibly other COX- selective are effective in reducing, but not eliminating, the risk of symptomatic ulcers and ulcer complications. D. Lichtensten, M Wolfe JAMA 8() :97-9 Gain of the authors and drug company, reprints of CLASS paper Citation frequency x of other articles in the same issue Sales of from US$ m in to m in Missing Data on Celebrex Full study altered picture of drug Washington Post August, In Feb, M. Wolfe was shown the complete data in FDA s Arthritis Advisory Committee I am furious. I wrote the editorial. I looked like a fool FDA put raw data and FDA s own statistical analysis on its website Reporting of -month vs - month data in a clinical trial of Are selective COX inhibitors superior to traditional nonsteroidal anti-inflammatory drugs? JAMA Nov, BMJ June,

5 Critique () the study design Critique () the outcome measure Fact : separate studies of different protocols in terms of design, outcomes, duration of follow-up and analysis A -arm trial comparing with Ibuprofen and Diclofenac Incidence of symptomatic ulcers and ulcer complications as study end point Fact : FDA wanted to address ulcers complications, NOT symptomatic ulcers as COX inhibitors could adversely affect the ulcer healing process 7 All Patients P=.9 /8 / / P=. 9/8 8 Critique () the duration of study vs Ibuprofen vs Diclofenac CLASS only analyzed outcome at months -month trial -month trial The benefit of reduction in ulcer complications disappeared at months BMJ June, 9 BMJ June,

6 Critique () serious adverse events Outcome Other NSAID CLASS RR ARR ARI NNT NNH (9m) Mortality.8.. NS NS Complicat ed ulcers Other SAE...8 NS NS.8.8. Comparison of upper gastrointestinal toxicity of rofecoxib and naproxen in patients with rheumatoid arthritis VIGOR study Total SAE NS NS NEJM Nov, Outcome Mortality Complic ated ulcers Other SAE Total SAE Rofecoxib..7. NS Myocardial infarction (.7-.8) RR..9 (.7-.);.9 NNH.. (.-.78) Thrombotic cardiovascular events RR 8..8 (.9-);. NNH (.-.) 9. VIGOR STUDY Naproxen 7.8 RR (9% CI). (.-.) ARR ARI. NNT NNH (9m) NS 9 7 Explanation: A differential drop out rate of NSAID patients The absolute with GI number intolerance of dropouts / and symptomatic withdrawals (GI ulcers, events suggesting or overall) that those increased patients gradually at greater without risk any were no longer sudden in increase the study after months Withdrawal rate constant in different groups during the whole study period Conclusion Use of aspirin obscured the ability to accurately compare the GI safety of to other Published version of CLASS failed to disclose the full picture on efficacy and safety Remedies Meta-analysis performed for published and unpublished data by industry-independent bodies FDA : For upper GI safety and also for global safety, there does not appear to be any meaningful advantage for COX- inhibitors associated with increase incidence of serious adverse events Wide dissemination of the findings of re-analysis to counterbalance the misleading results of CLASS

7 Drug Unit cost (HK$) Refecoxib.mg & mg.9 mg. mg. Ibuprofen mg.7 Diclofenac mg. 7mg SR.7 mg SR. Naproxen mg. 7 (DAC )