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Jonathan J Deeks a Centre for
Statistics in Medicine, Institute of Health Sciences, Headington,
Oxford OX3 7LF, b Pfizer Global Research and Development, Sandwich, Kent CT13
9NJ Correspondence to: J J Deeks
jon.deeks{at}cancer.org.uk
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Abstract |
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Objective:
To determine the efficacy,
gastrointestinal safety, and tolerability of celecoxib (a
cyclo-oxygenase 2 (COX 2) inhibitor) used in the treatment of
osteoarthritis and rheumatoid arthritis.
Design:
Systematic review of randomised trials
that compared at least 12 weeks' celecoxib treatment with another
non-steroidal anti-inflammatory drug (NSAID) or placebo and
reported efficacy, tolerability, or safety. Trials identified from
manufacturer and by searching electronic databases and evaluated
according to predefined inclusion and quality criteria. Data combined
through meta-analysis.
Participants:
15 187 patients with osteoarthritis or
rheumatoid arthritis.
Main outcome measures:
Efficacy: Western Ontario and
McMaster universities osteoarthritis index; American College of
Rheumatology responder index and joint scores for rheumatoid arthritis.
Tolerability: withdrawal rates for adverse effects. Gastrointestinal
safety: incidence of ulcers, bleeds, perforations, and obstructions.
Results:
Nine randomised controlled trials were
included. Celecoxib and NSAIDS were equally effective for all efficacy
outcomes. Compared with those taking other NSAIDs, in patients taking
celecoxib the rate of withdrawals due to adverse gastrointestinal
events was 46% lower (95% confidence interval 29% to 58%; NNT 35 at
three months), the incidence of ulcers detectable by endoscopy was 71% lower (59% to 79%; NNT 6 at three months), and the incidence of symptoms of ulcers, perforations, bleeds, and obstructions was 39%
lower (4% to 61%; NNT 208 at six months). Subgroup analysis of
patients taking aspirin showed that the incidence of ulcers detected by
endoscopy was reduced by 51% (14% to 72%) in those given celecoxib
compared with other NSAIDs. The reduction was greater (73%, 52% to
84%) in those not taking aspirin.
Conclusion:
Celecoxib is as effective as other NSAIDs for relief of symptoms of osteoarthritis and rheumatoid arthritis and
has significantly improved gastrointestinal safety and tolerability.
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What is already known on this topic
COX 2 specific inhibitors are claimed to cause fewer gastrointestinal complications The National Institute for Clinical Excellence has recently recommended that COX 2 specific inhibitors are used in patients with arthritis who are at risk of gastrointestinal complications but not in those taking prophylactic aspirin What this study adds
Celecoxib has significantly improved gastrointestinal safety and tolerability compared with standard NSAIDs An improvement in gastrointestinal safety was still evident in patients who were also taking aspirin |
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Introduction |
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Non-steroidal anti-inflammatory drugs (NSAIDs) are prescribed for the treatment of osteoarthritis and rheumatoid arthritis and provide effective relief from symptoms. However, serious gastrointestinal complications occur with their use. There are between 2000-2500 deaths annually in the United Kingdom due to use of NSAIDs. 1 2
NSAIDs control pain and inflammation by inhibiting cyclo-oxygenase 1 and 2 (COX 1 and COX 2) enzymes. Inhibition of the COX 1 enzyme is responsible for the associated gastrointestinal toxicity. Celecoxib was developed as a COX 2 specific inhibitor to provide relief without the associated gastrointestinal complications.
We conducted a systematic review of all published and unpublished
trials to determine if celecoxib is as effective as other NSAIDs for
the treatment of osteoarthritis and rheumatoid arthritis and if there
is evidence of greater gastrointestinal tolerability and safety.
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Methods |
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Inclusion criteria
We included randomised controlled trials if they were double
blind, compared celecoxib at a licensed therapeutic dose for at least
12 weeks with placebo or another NSAID at a standard dose in patients
with active rheumatoid arthritis or osteoarthritis, and reported
efficacy, tolerability, or safety outcomes. In addition, to investigate
safety we considered data on doses of celecoxib above those recommended
for treatment. Placebo comparisons were included to demonstrate the
sensitivity of efficacy outcomes and to investigate gastrointestinal toxicity.
Outcome measures
We present results of the Western Ontario and McMaster
universities (WOMAC) osteoarthritis index for pain (scored 0 to 20),
stiffness (scored 0 to 8), and physical function (scored 0 to 68). We
used the American College of Rheumatology (ACR-20) responder index and
evaluations of improvement in the numbers of painful or tender and
swollen joints for trials of rheumatoid arthritis.
Drug tolerability was assessed by considering rates of withdrawal due to any adverse event at 12 weeks. Gastrointestinal safety was assessed by comparing the incidence of ulcers detected by routine endoscopy at 12 and 24 weeks and the incidence of symptomatic ulcers, perforations, bleeds, and obstructions up to 24 weeks.
Study identification
We aimed to include all randomised trials of celecoxib, regardless
of whether or not they had been published. We obtained from the
manufacturer reports from all industry sponsored randomised controlled
trials that were completed by 25 May 2000 and that compared celecoxib
with placebo or other NSAID in people with osteoarthritis and
rheumatoid arthritis. We also searched Medline, Embase, and the
Cochrane controlled trials register from 1998 to March 2001 using the
search terms celecoxib, Celebrex, and SC-58635.
Trial quality and data abstraction
To assess the potential for bias we considered the method of
randomisation, concealment of allocation, blinding of trial
investigators and patients, completeness of follow up, and analysis
according to intention to treat. Summary outcome data were extracted
from the original company trial reports.
Data synthesis
Separate meta-analyses were undertaken for each comparison and
outcome. We analysed efficacy data separately for osteoarthritis and
rheumatoid arthritis. We analysed tolerability and safety data for the
two diseases combined.
Dichotomous data were summarised as relative risks; continuous data were summarised as differences in means.
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Results |
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We obtained reports of 17 trials, nine of which (15 187 patients) fulfilled the inclusion criteria.3-11 See the long version of this paper on bmj.com for full details of the studies. All nine trials were of high quality.
After 12 weeks of treatment, 56% of patients in the placebo group had dropped out due to poor efficacy or adverse events. Dropout rates in celecoxib and other NSAID groups were lower (39% on celecoxib 200 mg per day; 32% on celecoxib 400 mg per day; 39% on naproxen 1000 mg per day; 26% on diclofenac 150 mg per day).
Effectiveness of celecoxib for treatment at 12 weeks
Rheumatoid arthritis
Celecoxib provided significant improvement in all outcomes compared with placebo.
4 9
Three trials compared celecoxib with other NSAIDS (naproxen 500 mg
twice daily in two trials
4 9
and diclofenac 75 mg twice
daily in one7). There were no significant differences,
with all drugs appearing equally effective for all outcomes. With
celecoxib the ACR-20 responder rate was 4% higher (95% confidence
interval
20% to 36%), 9% more (
10% to 32%) showed
improvement in the number of painful or tender joints, and 2% more
(
15% to 22%) showed improvement in the number of swollen joints
(see also bmj.com).
Osteoarthritis
Compared with placebo celecoxib resulted in
significant improvement in all components of the WOMAC scale as well as
the composite WOMAC score.
3 10 11
The same three trials
compared celecoxib with naproxen 500 mg twice daily in 1917 patients.
There were no significant differences between celecoxib and naproxen,
with both drugs appearing equally effective for all components of the
WOMAC scale: pain (mean difference 0.0,
0.7 to 0.7), stiffness (0.1,
0.1 to 0.2), and physical function (0.4,
1.0 to 1.8) and the
composite WOMAC score (0.4,
1.5 to 2.3) (see bmj.com).
Tolerability
Celecoxib versus placebo
Withdrawal due to adverse
events occurred more often on celecoxib than on placebo, both for any
adverse event (relative risk 1.49, 1.15 to 1.92) and for all
gastrointestinal adverse events (1.68, 1.07 to 2.65) (fig 1). However,
withdrawals due to abdominal pain, diarrhoea, dyspepsia, nausea, or
vomiting were not significantly increased with celecoxib compared with
placebo.
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Celecoxib versus NSAID
There was no significant difference
between celecoxib and NSAID in the incidence of withdrawals for all
adverse events (fig 1). However, there was a significant decrease in
the number of withdrawals due to gastrointestinal adverse events, corresponding to a number needed to treat of 35 at three months. Of the
specific gastrointestinal adverse events, there were significantly fewer withdrawals due to abdominal pain and dyspepsia in the celecoxib group compared with other NSAIDs. The incidence of withdrawals due to
diarrhoea, nausea, or vomiting were not significantly different between
celecoxib and other NSAIDs.
Ulcers detected by endoscopy
Celecoxib versus placebo
Although there was no
significant difference in the number of ulcers detected between the
groups, the results were compatible with up to a threefold increase in
the incidence of ulcers (1.53, 0.73 to 3.21).
Celecoxib versus NSAID
The incidence of ulcers was 71%
(59% to 79%) lower in those taking celecoxib compared with other
NSAIDs, corresponding to a number needed to treat of six at three
months. The one study that reported ulcers detected by endoscopy at 24 weeks found a similar significant reduction, with incidence being 75%
(47% to 88%) lower in those taking celecoxib.7
Ulcers, perforations, bleeds, and obstructions at 24 weeks
The CLASS study of 7968 patients investigated the incidence of
serious upper gastrointestinal events (bleeds, perforations,
obstructions) in those taking celecoxib (3987 given celecoxib 800 mg
per day; above the recommended dose) compared with other NSAIDs (1985 took ibuprofen, 1996 took diclofenac).8 Patients were
monitored and withdrawn from the trial due to adverse events, if
endoscopy indicated a symptomatic ulcer, if prolonged use of an ulcer
healing treatment was required, or if treatment did not control the
symptoms of arthritis. Outcomes at six months were considered as the
overall rates of withdrawal were more comparable after six months (40%
for celecoxib, 42% for diclofenac, and 47% for ibuprofen) than at the
final follow up (55%, 53% and 65%). With celecoxib the incidence of
bleeds, perforations, or obstructions (n=11) was nearly half that
with the other NSAIDs (n=20), but this difference was not significant
(fig 2).
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Among the participants withdrawn from the trial for safety reasons, 19 patients taking celecoxib were found to have ulcers on endoscopy compared with 29 patients taking other NSAIDs. When ulcers were included within the definition of serious adverse events, the reduction of serious adverse events with celecoxib decreased to 39% (corresponding to a number needed to treat of 208 at six months) but became significant (fig 2).
Benefits of celecoxib in patients receiving low dose aspirin
Four trials compared celecoxib with other NSAIDs and showed that
the incidence of ulcers detected by routine endoscopy were
significantly reduced both in patients taking and not taking aspirin
(up to 325 mg/day).
4-5 10
The benefit of celecoxib
seemed greater in those not taking aspirin, although the difference
between subgroups was not significant (P=0.18, fig
3).
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In the CLASS study the reduction in the incidence of clinical ulcers,
perforation, bleeds, and obstructions was also smaller in those taking
aspirin (19% reduction,
63% to 60%) than in those not taking
aspirin (50% reduction, 8% to 72%).8 This difference between the subgroups was not significant (P=0.44).
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Discussion |
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In this review of randomised controlled trials we have shown that celecoxib is as effective as other NSAIDs for the relief from symptoms of osteoarthritis and rheumatoid arthritis. The confidence intervals around the point estimates of efficacy were reasonably narrow, which mean that it is unlikely that there were clinically important differences.
Our findings are robust and unlikely to be influenced by bias. Beyond the stated involvement of MDB, the industrial sponsors had no involvement in the review process once the protocol had been agreed. We included published and unpublished studies, and we insisted that the companies involved provided a signed legal statement confirming that they had made available data from all celecoxib trials that were completed before our inclusion date. We evaluated the impact of including unpublished studies by sensitivity analyses for main outcomes (see bmj.com); our findings and interpretation did not change. Results of further phase 4 trials (the Success trial) have recently been partially published in abstract form since we completed our search. We did not add these to our review as they are incomplete and could introduce bias.12
As we abstracted data directly from original trial reports we minimised the effects of missing data and errors in transcription. Access to individual patient data would have allowed us to investigate further any variation in treatment effect with patient characteristics.
All included trials were designed and executed to meet standards required for licensing. Although withdrawals were common, the potential biases due to unequal withdrawals act in a conservative direction.
For most analyses we did not detect any heterogeneity, which supports pooling of different doses of drugs and disease states. Each analysis comprised large numbers of patients, baseline characteristics were similar, all patients had active disease at the start of the study, and efficacy outcomes assessed were those routinely required for licensing of drugs for osteoarthritis and rheumatoid arthritis (WOMAC and ACR-20). Additional efficacy outcomes that we investigated but have not reported here showed similar patterns of benefit.
This review was limited to assessing only upper gastrointestinal safety. Recently the VIGOR (Vioxx gastrointestinal outcomes research) trial of rofecoxib has raised concerns about serious cardiovascular effects with the use of COX 2 inhibitors.13 While it is important to evaluate this concern, this was not possible here as the celecoxib trials we included did not report outcomes comparable with those assessed in VIGOR (all trials started recruitment before publication of VIGOR). This issue should be a priority for a future systematic review when adequate data on both celecoxib and rofecoxib are available.
Aspirin is commonly prescribed to prevent cardiovascular disease, and, like NSAIDs, it inhibits COX 1 thus increasing the risk of a gastrointestinal event. The present weight of evidence does not suggest that celecoxib should be withheld from aspirin users as currently recommended by the National Institute for Clinical Excellence (NICE), but further research should clarify the size of the possible reduction in efficacy in this group.
In conclusion, this meta-analysis provides strong evidence of the
effectiveness of celecoxib for relief of pain and inflammatory symptoms
of osteoarthritis and rheumatoid arthritis, the level of effectiveness
being equivalent to that of other NSAIDs. However, the tolerability and
gastrointestinal safety of celecoxib is substantially superior.
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Acknowledgments |
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Mark Layton (Pfizer) and Anne Hopkins (Searle) provided input into the review protocol and facilitated access to the full trial reports.
Contributors: See bmj.com
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Footnotes |
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Funding: Additional funding was provided to the Centre for Statistics in Medicine by Pfizer and Searle (now part of Pharmacia).
Competing interests: The review was undertaken independently at the Centre for Statistics in Medicine. LAS is employed on a fellowship funded by Pfizer. JJD has acted as a paid consultant to Pfizer and Pharmacia. MDB is an employee of Pfizer. The review was prepared as part of the submission to the UK National Institute of Clinical Excellence for appraisal of COX 2 selective inhibitors.
The full version of this article
appears on bmj.com
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References |
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| 1. | Blower AL, Brooks A, Fenn GC, Hill A, Pearce MY, Morant S, et al. Emergency admissions for upper gastrointestinal disease and their relation to NSAID use. Aliment Pharmacol Ther 1997; 11: 283-291[CrossRef][ISI][Medline]. |
| 2. | Tramer MR, Moore RA, Reynolds DJ, McQuay HJ. Quantitative estimation of rare adverse events which follow a biological progression: a new model applied to chronic NSAID use. Pain 2000; 85: 169-182[CrossRef][ISI][Medline]. |
| 3. | Bensen WG, Fiechtner JJ, McMillen JI, Zhao WW, Yu SS, Woods EM, et al. Treatment of osteoarthritis with celecoxib, a cyclooxygenase-2 inhibitor: a randomized controlled trial. Mayo Clin Proc 1999; 74: 1095-1105[ISI][Medline]. |
| 4. |
Simon LS, Weaver AL, Graham DY, Kivitz AJ, Lipsky PE, Hubbard RC, et al.
Anti-inflammatory and upper gastrointestinal effects of celecoxib in rheumatoid arthritis: a randomized controlled trial.
JAMA
1999;
282:
1921-1928 |
| 5. | Study 62. Integrated clinical and statistical report for a multicenter, double blind, parallel group study comparing the incidence of gastroduodenal ulcer associated with SC-58635 200 mg with that of naproxen 500 mg BID taken for 12 weeks in patients with osteoarthritis or rheumatoid arthritis. Pharmacia: Data on file. 1997. |
| 6. | Study 071. Integrated clinical and statistical report for a multicenter, double blind, parallel group study comparing the incidence of gastroduodenal ulcer associated with SC-58635 200 mg BID with that of diclofenac 75 mg BID and ibuprofen 800 mg TID, taken for 12 weeks in patients with osteoarthritis or rheumatoid arthritis. Pharmacia: Data on file. 1998. |
| 7. | Emery P, Zeidler H, Kvien TK, Guslandi M, Naudin R, Stead H, et al. Celecoxib versus diclofenac in long-term management of rheumatoid arthritis: randomised double-blind comparison. Lancet 1999; 354: 2106-2111[CrossRef][ISI][Medline]. |
| 8. |
Silverstein FE, Faich G, Goldstein JL, Simon LS, Pincus T, Whelton A, et al.
Gastrointestinal toxicity with celecoxib vs nonsteroidal anti-inflammatory drugs for osteoarthritis and rheumatoid arthritis: the CLASS study: a randomized controlled trial. Celecoxib long-term arthritis safety study.
JAMA
2000;
284:
1247-1255 |
| 9. | Zhao SZ, Fiechtner JI, Tindall EA, Dedhiya SD, Zhao WW, Osterhaus JT, et al. Evaluation of health-related quality of life of rheumatoid arthritis patients treated with celecoxib. Arthritis Care Res 2000; 13: 112-121. |
| 10. | Zhao SZ, McMillen JI, Markenson JA, Dedhiya SD, Zhao WW, Osterhaus JT, et al. Evaluation of the functional status aspects of health-related quality of life of patients with osteoarthritis treated with celecoxib. Pharmacotherapy 1999; 19: 1269-1278[CrossRef][ISI][Medline]. |
| 11. | Study 054. Integrated clinical and statistical report for a double-blind placebo controlled, randomised comparison study of the efficacy and safety of SC-58635 50 mg, 100 mg and 200 mg BID and naproxen 500 mg BID in treating the signs and symptoms of osteoarthritis of the hip. Pharmacia: Data on file. 1997. |
| 12. | Singh G, Goldstein J, Fort J, Bello A, Boots S. Success-I in osteoarthritis (OA) trial: celecoxib has similar efficacy to the conventional NSAIDS [abstract]. J Rheumatol 2001; 28(suppl 6.3): 6[Medline]. |
| 13. |
Bombardier C, Laine L, Reicin A, Shapiro D, Burgos-Vargas R, Davis B, et al.
Comparison of upper gastrointestinal toxicity of rofecoxib and naproxen in patients with rheumatoid arthritis. VIGOR study group.
N Engl J Med
2000;
343:
1520-1528 |
(Accepted 27 March 2002)
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