Biomedical subjects

Jeffrey D Kent

Publications and source records attributed to Jeffrey D Kent.

3 recordsLinked to original sources

PubMed2003

The COX-2 selective inhibitor, valdecoxib, does not impair platelet function in the elderly: results of a randomized controlled trial.

The effects of the new cyclooxygenase (COX)-2 selective inhibitor, valdecoxib (40 mg bid; n = 17), on platelet function were evaluated, along with ibuprofen (800 mg tid; n = 15) and placebo (n = 15), in healthy elderly subjects (65-85 years) in this 7.5-day, randomized, single-center, double-blind study. Platelet aggregation (to sodium arachidonate, collagen, and adenosine diphosphate), bleeding time, and serum thromboxane B2 (TxB2) concentrations were measured up to 8 hours postdose on Days 1 and 8. Valdecoxib had no platelet effects, while ibuprofen significantly decreased platelet aggregation, significantly increased bleeding time (2-4 h postdose on each day), and significantly decreased TxB2 levels at all time points. In conclusion, unlike ibuprofen, valdecoxib 40 mg bid spares platelet COX-1 function in healthy elderly subjects. Valdecoxib's lack of effect on platelet aggregation and bleeding time suggests that it will have an improved clinical profile over nonselective NSAIDs, particularly in patients for whom bleeding complications are a concern.

Adenosine Diphosphate↗

PubMed2002

Valdecoxib does not impair platelet function.

The platelet effects of a supratherapeutic dose of the new cyclooxygenase (COX)-2 specific inhibitor, valdecoxib (40 mg twice a day), naproxen 500 mg twice a day, diclofenac 75 mg twice a day, and placebo were compared in 62 healthy adult subjects in this 7(1/2) day single-center, randomized, placebo-controlled trial. Platelet aggregation responses (to arachidonate [AA], collagen, and adenosine diphosphate [ADP]), bleeding time, and serum thromboxane B(2) (TxB(2)) concentrations were measured at baseline and at regular intervals on days 1 and 8. Valdecoxib had no effect on platelet function. Naproxen and diclofenac significantly reduced the platelet aggregation response to AA and to a lesser extent collagen and ADP at most assessments compared with placebo. Naproxen significantly lowered serum TxB(2) levels. In contrast to standard doses of 2 nonsteroidal antiinflammatory drugs (NSAIDs), a supratherapeutic valdecoxib dosage does not impair platelet function (COX-1). Valdecoxib may be a safer analgesic option than conventional NSAIDs in patients for whom bleeding complications are a concern. (Am J Emerg Med 2002;20:275-281.

Adolescent↗

PubMed2002

Incidence of gastroduodenal ulcers associated with valdecoxib compared with that of ibuprofen and diclofenac in patients with osteoarthritis.

OBJECTIVE: To determine whether valdecoxib, at chronic arthritis doses, has the characteristics of a cyclo-oxygenase 2 (COX-2) specific inhibitor, as measured by a reduced incidence of upper-gastrointestinal ulceration compared with conventional nonsteroidal anti-inflammatory drugs (NSAIDs). METHODS: This double-blind, multicentre, placebo-controlled, parallel-group study compared the incidence of gastroduodenal ulcers associated with valdecoxib 10 mg daily (q.d.) and 20 mg q.d. with that of ibuprofen 800 mg three times daily (t.i.d.) or diclofenac 75 mg twice daily (b.i.d.) when administered over a 12-week period. The incidence of gastroduodenal ulcers was assessed by upper-gastrointestinal endoscopy, performed at baseline and again at the end of week 12 (or at early study termination). Efficacy assessments were performed at baseline and at weeks 2, 6 and 12 using Patient's and Physician's Global Assessments of Arthritis. RESULTS: A total of 1052 osteoarthritis patients were enrolled into the trial. The incidence of gastroduodenal ulcers over 12 weeks was 5% in patients receiving valdecoxib 10 mg q.d., 4% in patients receiving valdecoxib 20 mg q.d., 7% in patients receiving placebo, 16% in patients receiving ibuprofen 800 mg t.i.d. (P <0.05 v. placebo), and 17% in patients receiving diclofenac 75 mg b.i.d. (P <0.05 v. placebo). The incidence of gastroduodenal ulcers at week 12 seen in the ibuprofen 800 mg t.i.d. and diclofenac 75 mg b.i.d. groups was significantly higher than that in the valdecoxib 10 mg q.d. and valdecoxib 20 mg q.d. groups (P <0.05). The incidence rates of gastroduodenal ulcers were not significantly different between the valdecoxib treatment groups or between valdecoxib- and placebo-treated patients. Efficacy responses to valdecoxib 10 mg and 20 mg q.d. were significantly greater than placebo and comparable with both ibuprofen 800 mg t.i.d. and diclofenac 75 mg b.i.d. CONCLUSIONS: The results of the study demonstrate that valdecoxib has an upper-gastrointestinal safety profile typical of a COX-2 specific inhibitor. Overall, the data indicate that administration of valdecoxib offers similar efficacy for the treatment of osteoarthritis but improved upper-gastrointestinal safety compared with the conventional NSAIDs, ibuprofen and diclofenac, based on the significantly lower incidence of gastroduodenal ulcers detected by endoscopy.

Adult↗