Etoricoxib when administered orally at therapeutic concentrations, is a selective inhibitor of cyclooxygenase-2 (COX-2). In clinical pharmacological studies etorikoksib dose-dependent inhibition of COX-2 without affecting COX-1 with a daily dose of up to 150 mg. The drug does not inhibit the synthesis of prostaglandins in the gastric mucosa and does not affect the function of platelets. Cyclooxygenase is responsible for the formation of prostaglandins. Two isoforms of cyclooxygenase - COX-1 and COX-2 - are isolated. COX-2 is an isoenzyme that is induced by various proinflammatory mediators and is considered as the main enzyme responsible for the synthesis of prostanoid mediators of pain, inflammation and fever. COX-2 is involved in the processes of ovulation, implantation and closure of the arterial duct, regulation of kidney function and the central nervous system (induction of fever, pain sensations, cognitive function), and may play a role in the healing of ulcers. COX-2 was found in the tissues surrounding the stomach ulcer in humans, but its significance for ulcer healing is not established.
Efficiency
In patients with osteoarthritis (OD) etorikoksib When applied at a dose of 60 mg once a day, a reliably reduced pain and an improvement in the assessment of their condition by patients.These beneficial effects were observed on the second day of treatment and persisted for 52 weeks. Studies of etorikoksib when used at a dose of 30 mg once daily (using similar methods of evaluation) showed efficacy compared with placebo during the 12-week treatment period. In a study to determine the optimal dose, etorikoksib when administered at a dose of 60 mg, showed a significantly greater improvement than a 30 mg dose for all three primary endpoints after 6 weeks of treatment. A dose of 30 mg has not been studied with osteoarthritis of the joints of the hands. In patients with rheumatoid arthritis (RA) etorikoksib when used in a dose of 90 mg alone once a day provided a reliable reduction of pain and inflammation and improved mobility. These beneficial effects persisted during the treatment period of 12 weeks.
Patients with acute gouty arthritis etorikoksib when administered at a dose of 120 mg once a day during the entire treatment period of eight days, reduced moderate and severe pain in the joints and inflammation.The efficacy was comparable to that of indomethacin when administered at a dose of 50 mg three times a day. Reduction of pain was noted already four hours after the start of treatment.
In patients with ankylosing spondylitis etorikoksib when applied at a dose of 90 mg once a day, provided a reliable reduction in back pain, inflammation, stiffness, and improved functions. The clinical efficacy of etorikoksib was already observed on the second day of treatment and persisted throughout the treatment period of 52 weeks.
In a clinical study on pain after dental surgery etorikoksib in a dose of 90 mg was administered once a day for three days. In a subgroup of patients with moderate pain (with baseline assessment) etorikoksib when used at a dose of 90 mg had the same analgesic effect as ibuprofen in a dose of 600 mg (16.11 versus 16.39; P = 0.722) and was superior in efficiency to a combination of paracetamol / codeine 600 mg / 60 mg (11.00, P <0.001) and placebo (6.84, P <0.001) according to the overall pain reduction score for the first 6 hours (TOPAR6). The proportion of patients who needed fast-acting analgesics within the first 24 hours after taking the study drugs,was 40.8% with etorikoksiba at a dose of 90 mg, 25.5% with ibuprofen 600 mg every 6 hours and 46.7% with a combination of paracetamol / codeine at a dose of 600 mg / 60 mg every 6 hours compared to from 76.2% in the placebo group. In this study, the median onset of action (a measurable reduction in pain) with etoricoxib 90 mg was 28 minutes after taking the drug.
Bsafety
Program MEDAL (Multinational Long-Term Appointment Evaluation Program Thisoricoxib and Diclofenac in Arthritis)
Program MEDAL was a prospective safety assessment program on based cardiovascular (CS) phenomena from the combined data of three randomized, double-blind, actively-controlled studies: MEDAL, EDGE II and EDGE.
Study MEDAL was a study, the duration of which was determined by the achievement of end points (SS phenomena), which included 17804 patients with OA and 5,700 patients with RA who received etorikoksib in a dose of 60 mg (OA) or 90 mg (OA and RA) or diclofenac in a dose of 150 mg per day on average for 20.3 months (a maximum of 42.3 months, a median of 21.3 months). In this study, only serious adverse events and cases of drop-out from the study were recorded due to any undesirable events.
In studies EDGE and EDGE II compared the gastrointestinal tolerance of etorikoksib and diclofenac. Study EDGE included 7111 patients with OA who received etorikoksib in a dose of 90 mg per day (1.5 times the dose recommended for OA) or diclofenac in a dose of 150 mg per day on average for 9.1 months (a maximum of 16.6 months, a median of 11.4 months). Study EDGE II included 4,086 patients with RA who committed etorikoksib in a dose of 90 mg per day or diclofenac in a dose of 150 mg per day on average for 19.2 months (a maximum of 33.1 months, a median of 24 months).
In the joint Program MEDAL 34701 patients with OA or RA received treatment for an average of 17.9 months (a maximum of 42.3 months, a median of 16.3 months), and about 12 800 patients received treatment for more than 24 months. Included in the Program MEDAL of patients at baseline, a wide spectrum of CC and gastrointestinal risk factors was recorded. Patients with recent myocardial infarction, as well as with coronary artery bypass grafting or percutaneous coronary intervention for 6 months prior to enrollment were excluded. In studies, it was allowed to use gastroprotectors and low doses acpIrina.
General security
There were no significant differences between etorikoksib and diclofenac with regard to the frequency of thrombotic SS events. Cardiorenal adverse events were more frequently observed with etoricoxib than with diclofenac; this effect was dose-dependent (some results are presented below). Undesirable effects from the gastrointestinal tract (GIT) and liver were significantly more often observed with diclofenac than with etorikoksib. Frequency of adverse events in studies EDGE and EDGE II, as well as adverse events recognized as serious or requiring withdrawal of treatment, in the study MEDAL was higher in the appointment of etorikoksiba than with the appointment of diclofenac.
Results of safety assessment for cardiovascular system
The incidence of confirmed severe thrombotic SS adverse events (including cardiac, cerebrovascular and peripheral vascular events) was comparable between the groups receiving etorikoksib or diclofenac (the data are given in the table below). The frequency of thrombotic events did not reveal statistically significant differences between etorikoksibom and diclofenac in all the analyzed subgroups,including categories of patients in the range of the initial CC risk. The relative risk for confirmed serious thrombotic SS adverse events was similar for etorikoksib (when taken at a dose of 60 mg or 90 mg) and diclofenac (when taken in a dose of 150 mg).
Table "Frequency of confirmed thrombotic SS events (Program MEDAL)"
| Etoricoxib (N = 16819) 25836 patient-years | Diclofenac (N = 16483) 24,766 patient-years | Comparison between treatments |
Frequency1 (95% CI) | Frequency1 (95% CI) | Relative risk (95% CI) |
Confirmed thrombotic SS serious adverse events |
When fulfilling protocol requirements | 1,24 (1,11, 1,38) | 1,30(1,17, 1,45) | 0,95 (0,81, 1,11) |
Depending on the treatment prescribed | 1,25 (1,14, 1,36) | 1,19 (1,08, 1,30) | 1,05 (0,93,1,19) |
Confirmed cardiac events |
When fulfilling protocol requirements | 0,71 (0,61,0,82) | 0,78 (0,68, 0,90) | 0,90 (0,74, 1,10) |
In dependence on the prescribed treatment | 0,69 (0,61,0,78) | 0,70 (0,62, 0,79) | 0,99 (0,84, 1,17) |
Confirmed cerebrovascular events |
When fulfilling protocol requirements | 0,34 (0,28. 0,42) | 0,32 (0,25, 0.40) | 1.08 (0,80, 1,46) |
Depending on the treatment prescribed | 0,33 (0.28, 0,39) | 0,29 (0,24, 0,35) | 1,12 (0,87, 1,44) |
Confirmed peripheral vascular phenomena |
When fulfilling protocol requirements | 0,20 (0,15,0,27) | 0,22 (0,17, 0,29) | 0,92 (0,63, 1,35) |
Depending on the treatment prescribed | 0,24 (0,20, 0.30) | 0,23 (0,18, 0.28) | 1.08 (0.81, 1,44) |
1 - The number of phenomena per 100 patient-years; CI = confidence interval; N= total the number of patients included in the population of patients who fulfilled the protocol requirements. When fulfilling the requirements of the protocol, all the phenomena that developed against the background of the therapy being studied or within 14 days after its termination (patients who received <75% of the study drug and patients who took non-NSAIDs> 10% of the time were excluded). Depending on the treatment prescribed, all confirmed events that developed before the end of the study (patients included who could be subjected to unintended interventions after stopping the study drug were included). General information number of randomized patients: n = 17412 for etoricoxib and n= 17289 for diclofenac. |
MOP mortality and total mortality were comparable between the treatment groups etorikoksibom and diclofenac.
Kardiorenal phenomena
Approximately 50% of patients included in the study MEDAL, at an initial estimation the arterial hypertensia in the anamnesis has been registered. The frequency of elimination due to adverse events associated with hypertension was statistically significantly higher for etorikoksiba than for diclofenac. The incidence of adverse events associated with chronic heart failure (drop-out and serious events) was similar for etorikoksiba at a dose of 60 mg and diclofenac 150 mg,but it was higher for etoricoxib 90 mg compared with diclofenac at a dose of 150 mg (statistically significantly higher for etoricoxib 90 mg compared with diclofenac at a dose of 150 mg in study group OA MEDAL). The frequency of confirmed adverse events associated with congestive heart failure (phenomena which were severe and resulted in hospitalization or emergency room visit) was slightly higher for etoricoxib compared with diclofenac at a dose of 150 mg; this effect was dose-dependent. The frequency of dropout cases due to adverse events associated with edema was higher for etorikoksib compared with diclofenac at a dose of 150 mg; this effect was dose-dependent (statistically significant for etorikoksiba in a dose of 90 mg, but not for etorikoksiba in a dose of 60 mg). Results of assessing cardiorenal safety in studies EDGE and EDGE II consistent with the results in the study MEDAL
In some studies of the Program MEDAL absolute frequency drop-out in any treatment group for etoricoxib (60 mg or 90 mg) amounted to 2.6% due to hypertension, up to 1.9% due to swelling and to 1.1% in relation to chronic heart insufficiency.In patients taking ethornecoxib at a dose of 90 mg, the dropout rate was higher in the study than in patients taking etrncoxib at a dose of 60 mg. The results of the evaluation of gastrointestinal tolerance in the Program MEDAL
In each of the three studies included in the Program MEDAL, the drop-out rate for any clinical adverse gastrointestinal event (eg, dyspepsia, abdominal pain, ulcers) was significantly lower for etorikoxib than diclofenac. The dropout rate from the study due to undesirable GIT clinical events for 100 patient-years for the entire study period was as follows: 3.23 for etoricoxib and 4.96 for diclofenac in the study MEDAL; 9.12 for etoricoxib and 12.28 for diclofenac in the study EDGE, and 3.71 for etoricoxib and 4.81 for diclofenac in the study EDGE II.
The results of the evaluation of GI safety in the Program MEDAL
In general, undesirable phenomena from the upper gastrointestinal tract were defined as perforations, ulcers and bleeding. Complicated undesired side effects from the upper gastrointestinal tract included perforation, obstruction and complicated bleeding; uncomplicated adverse events from the upper gastrointestinal tract included uncomplicated bleeding and uncomplicated ulcers.The overall incidence of adverse events from the upper gastrointestinal tract was significantly lower for etorikoksib in comparison with diclofenac. There were no significant differences between etorikoksib and diclofenac in the frequency of complicated events. For hemorrhagic adverse events on the part of the upper gastrointestinal tract (complicated and uncomplicated in the aggregate), there were no significant differences between etorikoksibom and diclofenac. The advantage of etorikoksib in relation to the upper gastrointestinal tract compared with diclofenac in patients taking aspirin at low doses (about 33% of patients) was not statistically significant.
The incidence of confirmed complicated and uncomplicated clinical adverse events from the upper GI tract for 100 patient-years (perforation, ulcers and bleeding) was 0.67 (95% CI 0.57, 0.77) for etoricoxib and 0.97 (95% CI 0.85, 1.10) for diclofenac, on the basis of which the relative risk was 0.69 (95% CI 0.57.0.83).
The frequency of confirmed adverse events on the part of the upper GI tract in elderly patients was studied; the maximum reduction in frequency was observed in patients aged ≥75 years-1.35 (95% CI 0.94, 1.87) compared with 2.78 (95% CI 2.14, 3.56) events per 100 patient- years for etorikoksib and diclofenac, respectively.The incidence of confirmed adverse events from the lower gastrointestinal tract (small or large intestine perforation, obstruction or bleeding) did not differ significantly between the groups receiving etorikoksib and diclofenac.
The results of the liver safety assessment in the Program MEDAL
Etorikoksib was statistically significantly lower at the drop-out rate because of undesirable liver side effects compared with diclofenac. In the joint Program MEDAL 0.3% of patients who received etorikoksib, and 2.7% of patients who received diclofenac, withdrew from the study due to adverse events on the part of the liver. The incidence of adverse events per 100 patient-years was 0.22 for etoricoxib and 1.84 for diclofenac (p <0.001 for etoricoxib versus diclofenac). Most of the adverse events on the part of the liver in the Program MEDAL were not serious.
Additional safety data associated with thrombotic CC events
In clinical trials, with the exception of research programs MEDAL, approximately 3100 patients received etorikoksib in a dose of ≥60 mg per day for 12 weeks or longer. Hc, there were significant differences in the incidence of confirmed serious thrombotic SS events in patients who received etorikoksib in a dose ≥60 mg, placebo or NSAIDs that do not contain naproxen. However, in comparison with patients receiving naproxen in a dose of 500 mg twice a day, the frequency of these events was higher in patients who received etorikoksib. The difference in antiaggregant activity between certain NSAIDs that inhibit COX-1 and selective inhibitors of COX-2 may be of clinical importance in patients at risk of developing thromboembolic events. Selective inhibitors of COX-2 inhibit the formation of systemic (and, possibly, endothelial) prostacyclin without affecting platelet thromboxane. The clinical significance of these observations is not established.
Additional safety data for the digestive tract
In two double-blind endoscopic studies lasting 12 weeks, the cumulative incidence of gastroduodenal ulcers was significantly lower in patients receiving etorikoksib in a dose of 120 mg once a day than in patients who received naproxen in a dose of 500 mg twice a day or ibuprofen in a dose of 800 mg three times a day. The frequency of ulceration in the appointment of etorikoksib was higher compared with placebo.
Research of kidney function in the elderly
In a randomized, double-blind, placebo-controlled parallel group study evaluated the effects of 15-day therapy etoricoxib (90 mg), celecoxib (200 mg twice daily), naproxen (500 mg twice daily) and placebo on the excretion of sodium by the kidneys, blood pressure (BP) and other indicators of kidney function in patients aged 60 to 85 years who received a diet with a sodium content of 200 meq / day. Etoricoxib, celecoxib and naproxen after 2 weeks of treatment had a similar effect on the excretion of sodium by the kidneys. All active comparators led to an increase in systolic blood pressure relative to placebo, however, etoricoxib therapy resulted in a statistically significant increase in systolic blood pressure at Day 14 compared to celecoxib and naproxen (mean change in systolic blood pressure compared to baseline: 7.7 etorikoksib- mmHg., celecoxib - 2.4 mm of mercury. Art. naproxen - 3.6 mm of mercury. st.).