Lack of effect of Imrecoxib, an innovative and moderate COX-2 inhibitor, on pharmacokinetics and pharmacodynamics of warfarin in healthy volunteers

Imrecoxib: Advances in Pharmacology and Therapeutics

Imrecoxib, a cyclooxygenase-2 (COX-2) selective non-steroidal anti-inflammatory drug (NSAID), was discovered via the balanced inhibition strategy of COX-1/COX-2. It is indicated for the relief of painful symptoms of osteoarthritis. There have been some pharmacological and therapeutic advances since the approval of imrecoxib in 2011. However, an update review in this aspect is not yet available. Relevant literature until January 2024 was identified by search of PubMed, Web of science, Embase and CNKI. From the perspective of efficacy, imrecoxib provides relief of osteoarthritis symptoms, and potential off-label use for treatment of idiopathic pulmonary fibrosis, perioperative pain, hand-foot syndrome, axial spondyloarthritis, COVID-19, cartilage injury, and malignancies such as lung and colon cancer. From a safety point of view, imrecoxib showed adverse effects common to NSAIDs; however, it has lower incidence of new-onset hypertension than other types of selective COX-2 inhibitors, less gastrointestinal toxicities than non-selective NSAIDs, weaker risk of drug interaction than celecoxib, and more suitable for elderly patients due to balanced inhibition of COX-1/COX-2. From a pharmacoeconomic perspective, imrecoxib is more cost-effective than celecoxib and diclofenac for osteoarthritis patients. With the deepening of the disease pathophysiology study of osteoarthritis, new therapeutic schemes and pharmacological mechanisms are constantly discovered. In the field of osteoarthritis treatment, mechanisms other than the analgesic and anti-inflammatory effects of COX-2 inhibitors are also being explored. Taken together, imrecoxib is a moderate selective COX-2 inhibitor with some advantages, and there would be more clinical applications and research opportunities in the future.

Inhibition of imrecoxib on mRNA and protein expression of CYP2C11 enzyme in rats

PURPOSE

To evaluate the effect of imrecoxib on CYP2C11 enzyme activity, mRNA and protein expression.

METHOD

An ultra-performance liquid chromatography (UPLC) method was established. Tolbutamide was selected as CYP2C11 enzyme-specific probe drug and incubated with imrecoxib in rat liver microsomes. The amount of 4-hydroxytolbutamide produced was measured by UPLC to investigate the effect of imrecoxib on CYP2C11 enzyme activity. Imrecoxib (10 mg/kg) was given by intragastric administration twice daily. After 1, 7 and 14 days of administration, liver tissues were taken. The expression of CYP2C11 enzyme mRNA was determined by reverse transcription-polymerase chain reaction (RT-PCR), and its protein expression was determined by Western Blot.

RESULTS

Imrecoxib concentration was inversely proportional to the production of 4-hydroxytolbutamide in liver microsomes. Imrecoxib demonstrated dose-dependent inhibitory effect on CYP2C11 activity with IC50=74.77 μM. After administration, RT-PCR showed CYP2C11 enzyme mRNA expressions were 65% (P<0.05), 35%, and 34% of control group, respectively (P<0.01). Western Blot showed CYP2C11 enzyme protein expressions were 80%, 37%, and 34% of control group, respectively (P<0.01).

CONCLUSION

Imrecoxib can reduce mRNA and protein expression of CYP2C11 enzyme in rat liver and inhibit the activity of CYP2C11 enzyme in a dose-dependent manner. However, it will not produce clinically significant drug interactions.

Dose investigation of imrecoxib in patients with renal insufficiency based on modelling and simulation

OBJECTIVE

Imrecoxib is a new moderately selective cyclooxygenase-2 (COX-2) inhibitor. A previous study has shown that drug exposure differs significantly in renally impaired patients. We aim to describe the population pharmacokinetics (PPK) of imrecoxib (M0) and its two metabolites (M1, M2) to provide a theoretical basis for investigating imrecoxib doses for renally impaired patients.

METHODS

Using PPK analysis, 24 patients with 257 different plasma concentrations were studied. Of these, 12 had severe renal impairment and 12 had normal renal function. The dose regimen was simulated based on the final model to compare the ratio (Cu,ss/IC50) of the average unbound concentration at steady state (Cu,ss) to the half-maximal inhibitory concentration (IC50) of COX-2.

RESULTS

Imrecoxib and its metabolite concentrations were satisfactorily described by a two-compartment with first-order transit absorption model for imrecoxib and a one-compartment model for its metabolites. Renal function was a significant binary covariate. Scenarios of '75 mg q12h' and '50 mg q8h' in renally impaired patients had similar Cu,ss/IC50 values with a '100 mg q12h' regimen in subjects with normal renal function.

CONCLUSION

A PPK model of imrecoxib and its two metabolites is presented. The renal insufficiency regimen should be reduced to '75 mg q12h' or '50 mg q8h'.