Richard C. Hubbard

Preliminary study of the safety and efficacy of SC-58635, a novel cyclooxygenase 2 inhibitor : Efficacy and safety in two placebo-controlled trials in osteoarthritis and rheumatoid arthritis, and studies of gastrointestinal and platelet effects

OBJECTIVE To investigate the efficacy and safety of SC-58635 (celecoxib), an antiinflammatory and analgesic agent that acts by selective cyclooxygenase 2 (COX-2) inhibition and is not expected to cause the typical gastrointestinal (GI), renal, and platelet-related side effects associated with inhibition of the COX-1 enzyme. METHODS Four phase II trials were performed: a 2-week osteoarthritis efficacy trial, a 4-week rheumatoid arthritis efficacy trial, a 1-week endoscopic study of GI mucosal effects, and a 1-week study of effects on platelet function. RESULTS The 2 arthritis trials identified SC-58635 dosage levels that were consistently effective in treating the signs and symptoms of arthritis and were distinguished from placebo on standard arthritis scales. In the upper GI endoscopy study, 19% of subjects receiving naproxen (6 of 32) developed gastric ulcers, whereas no ulcers occurred in subjects receiving SC-58635 or placebo. The study of platelet effects revealed no meaningful effect of SC-58635 on platelet aggregation or thromboxane B2 levels, whereas aspirin caused significant decreases in 2 of 3 platelet aggregation measures and thromboxane B2 levels. In all 4 trials, SC-58635 was well tolerated, with a safety profile similar to that of placebo. CONCLUSION SC-58635 achieves analgesic and antiinflammatory efficacy in arthritis through selective COX-2 inhibition, without showing any evidence of 2 of the toxic effects of COX-1 inhibition associated with nonsteroidal antiinflammatory drugs.

Treatment of Osteoarthritis With Celecoxib, a Cyclooxygenase-2 Inhibitor: A Randomized Controlled Trial

OBJECTIVE To compare the efficacy and safety of celecoxib, a cyclooxygenase-2 (COX-2) inhibitor, with those of naproxen, a nonsteroidal anti-inflammatory drug (NSAID), and placebo in the treatment of osteoarthritis of the knee. METHODS In this multicenter, randomized, double-blind, placebo-controlled trial, 1003 patients with symptomatic osteoarthritis of the knee were randomly assigned to receive celecoxib at doses of 50, 100, or 200 mg twice a day; naproxen, 500 mg twice a day; or placebo for 12 weeks. Patients were evaluated with standard measures of efficacy 2 to 7 days after discontinuing previous NSAID or analgesic therapy and after 2, 6, and 12 weeks of treatment with the study drug. RESULTS Celecoxib treatment led to significant improvement in the signs and symptoms of osteoarthritis as determined by all efficacy measures. Significant pain relief occurred within 2 days of the initiation of treatment, and maximum anti-inflammatory and analgesic activity, evident within 2 weeks, was sustained throughout the 12-week study. All celecoxib doses were efficacious compared with placebo, although the 50-mg twice-daily dosage regimen was minimally effective. The higher doses of celecoxib (100 and 200 mg twice a day) were similarly efficacious, and the magnitude of improvement observed with these dosing regimens was comparable to that seen with naproxen at a dose of 500 mg twice a day. All doses of celecoxib and naproxen were well tolerated. CONCLUSION COX-2 inhibition with celecoxib is an effective approach for the treatment of osteoarthritis, as seen by clinical improvement in signs and symptoms comparable to treatment with naproxen.

Reduced risk of upper gastrointestinal ulcer complications with celecoxib, a novel COX-2 inhibitor.

OBJECTIVE:The aim of this study was to assess the rate of upper gastrointestinal (UGI) ulcer complications (bleeding, perforation, or gastric outlet obstruction) associated with celecoxib, a specific COX-2 inhibitor, compared with the rate associated with nonspecific, nonsteroidal anti-inflammatory drugs (NSAIDs).METHODS:A pooled analysis was conducted of 14 multicenter, double-blind, randomized, controlled trials (RCTs) and a separate analysis of one long-term open label trial that assessed the efficacy and safety of celecoxib for symptomatic treatment of arthritis. The RCTs enrolled 11,008 patients with osteoarthritis or rheumatoid arthritis treated for 2–24 wk; the long-term open label trial enrolled 5,155 patients receiving celecoxib for a maximum of 2 yr. In the RCTs, patients were randomly assigned to receive placebo (n = 1,864; 208 patient-years), celecoxib 25–400 mg b.i.d. (n = 6,376; 1,020 patient-years), or a comparator NSAID (n = 2,768; 535 patient-years); NSAIDs were naproxen 500 mg b.i.d., diclofenac 50 or 75 mg b.i.d., or ibuprofen 800 mg t.i.d.). In the long-term, open-label trial, patients received celecoxib 100–400 mg b.i.d. for up to 2 yr (n = 5,155; 5,002 patient-years). The principal outcome measure of this analysis was development of a UGI ulcer complication, which was prospectively defined as bleeding, perforation, or gastric outlet obstruction. Ulcer complications were assessed and adjudicated by persons blinded to the patients treatment assignment or the study in which the patient participated.RESULTS:In the RCTs, UGI ulcer complications occurred in no placebo patients (0 of 1,864 patients), in 2 of 6,376 celecoxib patients (0.03%), and in 9 of 2,768 patients receiving an NSAID (0.33%), corresponding to annual incidences of 0.20% for celecoxib (p > 0.05vs placebo) and 1.68% for NSAIDs (p = 0.002vs celecoxib and placebo). In the long-term open-label trial, nine UGI ulcer complications occurred, for an incidence of 0.17% and an annualized incidence of 0.18%.CONCLUSIONS:The incidence of UGI ulcer complications associated with celecoxib was 8-fold lower than with nonspecific NSAIDs. The incidence of ulcer complications observed in celecoxib-treated patients was similar to that in patients receiving placebo in the RCTs, and to that in non-NSAID users reported in the literature.

Reduced incidence of gastroduodenal ulcers with celecoxib, a novel cyclooxygenase-2 inhibitor, compared to naproxen in patients with arthritis

OBJECTIVE:Nonsteroidal anti-inflammatory drugs (NSAIDs) block prostaglandin production by inhibiting cyclooxygenase (COX); they are believed to cause gastroduodenal damage by inhibiting the COX-1 isoform and to have analgesic and anti-inflammatory effects by inhibiting the COX-2 isoform. As compared to conventional NSAIDs, celecoxib, a COX-2 specific inhibitor, has been shown in previous single posttreatment endoscopy studies to be associated with lower gastroduodenal ulcer rates. In response to concerns that such studies may under-represent ulceration rates, the present serial endoscopy study was designed to compare cumulative gastroduodenal ulcer rates associated with the use of celecoxib to those of naproxen, a conventional NSAID.METHODS:In this double-blind, parallel-group, multicenter study, 537 patients with osteoarthritis (OA) or rheumatoid arthritis (RA) were randomized to treatment with celecoxib 200 mg b.i.d. (n = 270) or naproxen 500 mg b.i.d. (n = 267) for 12 wk. Gastroduodenal damage was determined from esophagogastroduodenoscopy after 4, 8, and 12 wk of therapy. Arthritis efficacy was evaluated with Patients and Physicians Global Assessments.RESULTS:Gastroduodenal ulcer rates after celecoxib and naproxen treatment were 4% versus 19% in the 0–4 wk interval (p < 0.001), 2% versus 14% in the 4–8 wk interval (p < 0.001), and 2% versus 10% in the 8–12 wk interval (p < 0.001), respectively. After 12 wk of treatment, the cumulative incidence of gastroduodenal ulcers was 9% with celecoxib and 41% with naproxen. In the celecoxib group, gastroduodenal ulcers were significantly associated with Helicobacter pylori status (p < 0.05), concurrent aspirin usage (p = 0.001), and a history of ulcer (p = 0.010), but not with disease type (OA/RA), age, gender, other relevant medical histories, or concurrent corticosteroid or disease-modifying antirheumatic drugs usage (p > 0.05). Celecoxib produced a significantly lower incidence rate of both gastric (p < 0.001) and duodenal (p < 0.030) ulcers. The two agents produced similar improvements in Patients and Physicians Global Assessments of arthritis efficacy. The incidence of adverse events and withdrawal rates did not differ significantly between treatments.CONCLUSIONS:As compared to naproxen (500 mg b.i.d.), use of celecoxib (200 mg b.i.d.), a COX-2 specific agent, at the recommended RA dose and twice the most frequently prescribed OA dose, was associated with lower rates of gastric, duodenal, and gastroduodenal ulcers but had comparable efficacy, in patients with OA and RA.

The injectable cyclooxygenase-2-specific inhibitor parecoxib sodium has analgesic efficacy when administered preoperatively.

Preoperative administration of analgesics may prevent or reduce hyperalgesia and inhibit inflammation and pain by reducing the synthesis of prostaglandins in response to surgical injury. We evaluated in this placebo-controlled study the analgesic efficacy and safety of single doses of parecoxib sodium (20, 40, and 80 mg IV) when administered before oral surgery. Efficacy assessments were recorded during the 24-h period after completion of surgery. All doses of parecoxib sodium were consistently and significantly superior to placebo as measured by time to rescue medication, proportion of patients requiring rescue medication, patient’s global assessment, and pain intensity. There were no significant differences between the Parecoxib Sodium 40- and 80-mg groups, suggesting that the analgesic effect of preoperatively administered parecoxib sodium reaches a plateau at 40 mg in this model. Forty-eight percent of the Parecoxib Sodium 40-mg group required rescue medication in the 24-h study period, compared with 93% of patients in the Placebo group. Overall, there were fewer adverse events in parecoxib sodium-treated patients compared with placebo. These findings suggest that preoperative administration of parecoxib sodium, the injectable prodrug of the cyclooxygenase-2 specific inhibitor valdecoxib, is effective, safe, and well tolerated for treating postoperative pain.

Efficacy and safety of intravenous parecoxib sodium in relieving acute postoperative pain following gynecologic laparotomy surgery.

Background This study tested the hypothesis that an injectable cyclooxygenase (COX)-2–specific inhibitor will be at least as effective and well tolerated as a COX-nonspecific conventional nonsteroidal antiinflammatory drug (NSAID) by comparing the analgesic efficacy and tolerability of one intravenous dose of parecoxib sodium, an injectable prodrug of the novel COX-2–specific inhibitor, valdecoxib, with ketorolac and placebo in postoperative laparotomy surgery patients. Intravenous morphine, 4 mg, was studied as a positive analgesic control. Methods In this multicenter, double-blinded, placebo-controlled study, women experiencing moderate-to-severe pain on the first day after abdominal hysterectomy or myomectomy received one intravenous dose of parecoxib sodium, 20 or 40 mg, ketorolac, 30 mg, morphine, 4 mg, or placebo. Analgesic efficacy and tolerability were evaluated for 24 h postdose or until patients, whose pain was not adequately controlled, opted to receive rescue analgesia. Results Two hundred two patients were enrolled. All treatment groups had comparable demographics and baseline pain status. All active treatments had an equally rapid time to onset of analgesia (10–23 min). Overall, each parecoxib sodium dose and ketorolac were significantly superior to morphine and placebo for most measures of analgesic efficacy at most time points, including a significantly longer (two- to threefold) time to rescue analgesia (P ≤ 0.05). All treatments were well tolerated. Conclusions Single intravenous doses of parecoxib sodium, 20 mg and 40 mg, have comparable analgesic effects and are well tolerated after laparotomy surgery. Parecoxib sodium appears to be as effective as intravenous ketorolac, 30 mg, and superior to intravenous morphine, 4 mg.

Parecoxib Sodium, a Parenteral Cyclooxygenase 2 Selective Inhibitor, Improves Morphine Analgesia and Is Opioid-sparing following Total Hip Arthroplasty

Background This study examined the opioid-sparing effectiveness, analgesic efficacy, and tolerability of postoperative administration of the parenteral cyclooxygenase 2 selective inhibitor, parecoxib sodium, in total hip arthroplasty patients. Methods This was a multicenter, multiple-dose, randomized, double-blind, placebo-controlled study to compare the opioid-sparing effects, analgesic efficacy, and tolerability of postoperative 20 and 40 mg intravenous parecoxib sodium with placebo in hip arthroplasty patients. The first dose of study medication was administered after surgery with an intravenous bolus dose of 4 mg morphine when patients first requested pain medication; remedication with the study medication occurred at 12 and 24 h. Subsequent morphine doses (1–2 mg) were administered by patient-controlled analgesia. Efficacy was assessed by total morphine used, pain relief and pain intensity, time to last dose of morphine, and Global Evaluation rating of the study medication. Results Parecoxib sodium, 20 and 40 mg, reduced the total amount of morphine required over 36 h by 22.1% (56.5 mg morphine) and 40.5% (43.1 mg morphine), respectively, compared with placebo (72.5 mg morphine;P < 0.01). Patients receiving 20 and 40 mg parecoxib sodium experienced significantly greater maximum pain relief compared with those in the placebo group (P < 0.05). Patients who received 20 and 40 mg parecoxib sodium discontinued PCA morphine earlier than patients receiving placebo and had significantly higher Global Evaluation ratings. Parecoxib sodium, 40 mg, plus morphine demonstrated a significantly lower incidence of fever and vomiting compared with placebo plus morphine. Conclusions Administration of parecoxib sodium with PCA morphine resulted in significantly improved postoperative analgesic management as defined by reduction in opioid requirement, lower pain scores, reduced time on PCA morphine, and higher Global Evaluation ratings.

A Pharmacokinetic Study of Intramuscular (IM) Parecoxib Sodium in Normal Subjects

A single‐center, double‐blind, placebo‐controlled, randomized study was conducted to determine the pharmacokinetics, safety, and tolerability of single, rising intramuscular (IM) doses and the single maximum tolerated dose of parecoxib sodium, a prodrug of the novel COX‐2 selective anti‐inflammatory analgesic drug valdecoxib, in 56 healthy male volunteers, ages 18 to 45 years inclusive. Cohorts of up to 6 subjects in each dose schedule were administered either parecoxib sodium (1 mg, 2 mg, 5 mg, 10 mg, 20 mg, or 40 mg) or matching placebo. Following IM administration, serial blood samples for measurement of plasma concentrations of parecoxib, valdecoxib, and valdecoxib metabolite (M1) were collected at predetermined intervals (from 15 minutes prior to dose and through 96 hours postdose). Urine collections were obtained for drug assay (from −12 to 0 hours, 0 to 12 hours, and 12 to 24 hours postdose). After IM administration, peak plasma concentrations of parecoxib were reached within 15 minutes and then declined rapidly as prodrug was converted to the active moiety, valdecoxib. Change in plasma concentrations of valdecoxib, which declined more slowly (t1/2 = 5.4–9.9 hours), reflected transformation to several metabolites, one of which was the minor active metabolite M1. As measured by the AUC0–∞, Cmax, and XU0–24 of valdecoxib, parecoxib sodium demonstrated dose proportionality when administered in the range of 1 mg to 40 mg of parecoxib. All single IM doses up to the maximum of 40 mg of parecoxib, as well as concentrations of up to 20 mg/ml, were well tolerated.

Upper gastrointestinal safety evaluation of parecoxib sodium, a new parenteral cyclooxygenase-2—specific inhibitor, compared with ketorolac, naproxen, and placebo

BACKGROUND Conventional nonsteroidal anti-inflammatory drugs (NSAIDs) are associated with an increased risk of ulcers and upper gastrointestinal (GI) ulcer complications, which has been attributed to the inhibition of cyclooxygenase-1. These risks are usually increased in elderly populations. Parecoxib sodium is an injectable prodrug of the cyclooxygenase-2-specific inhibitor valdecoxib that has exhibited analgesic activity in previous trials. OBJECTIVE The purpose of this study was to compare the GI safety and tolerability profile of parecoxib sodium with that of ketorolac, naproxen, and placebo in a 7-day endoscopic trial in elderly subjects. METHODS This was a randomized, double-blind, double-dummy, placebo-controlled, parallel-group study. After a normal baseline endoscopy, healthy elderly subjects aged 66 to 75 years were randomized to receive i.v. parecoxib sodium (10 mg BID), oral naproxen (500 mg BID), or placebo for 7 days, or placebo for 2 days followed by i.v. ketorolac (15 mg QID) for 5 days. Endoscopy was performed again after 7 days. RESULTS Among the first 17 subjects enrolled, ulcers were observed in all treatment groups except the parecoxib sodium group (ketorolac, 4/4 subjects; naproxen, 2/4 subjects; and placebo, 2/5 subjects). Four subjects in the ketorolac group and 1 subject in the naproxen group had multiple gastric ulcers or combined gastric and duodenal ulcers. Because of the unexpectedly high incidence of gastroduodenal ulcers observed, the study was terminated early and the randomization blind broken. CONCLUSION These findings suggest that elderly patients may be at risk for GI ulceration even after short-term use of the conventional NSAIDs ketorolac and naproxen.

Celecoxib Does Not Significantly Alter the Pharmacokinetics or Hypoprothrombinemic Effect of Warfarin in Healthy Subjects

The objective of this study was to determine the effects of celecoxib, an anti‐inflammatory/analgesic agent that primarily inhibits COX‐2 and not COX‐1 at therapeutic doses, on the steady‐state pharmacokinetic profile and hypoprothrombinemic effect of racemic warfarin in healthy volunteers. Twenty‐four healthy adult volunteers on maintenance doses of racemic warfarin (2–5 mg daily), stabilized to prothrombin times (PT) 1.2 to 1.7 times pretreatment PT values for 3 consecutive days, were randomized to receive concomitant celecoxib (200 mg bid) or placebo for 7 days in an open‐label, multiple‐dose, randomized, placebo‐controlled, parallel‐group study of warfarin pharmacokinetics and PT. Steady‐state exposure of S‐ and R‐warfarin (area under the curve [AUC]) and maximum plasma concentration (Cmax) in subjects receiving celecoxib were within 2% to 8% of the warfarin AUC and Cmax in subjects receiving placebo during the concomitant treatment period. In addition, PT values were not significantly different in subjects receiving warfarin and celecoxib concomitantly compared with subjects receiving warfarin and placebo. In conclusion, concomitant administration of celecoxib has no significant effect on PT or steady‐state pharmacokinetics of S‐ or R‐warfarin in healthy volunteers.