A pharmacokinetic comparison of ibuprofen sustained-release tablets given to young and elderly patients

In Situ Photopolymerization of Acrylamide Hydrogel to Coat Cellulose Acetate Nanofibers for Drug Delivery System

In this study we developed electrospun cellulose acetate nanofibers (CANFs) that were loaded with a model non-steroidal anti-inflammatory drug (NSAID) (ibuprofen, Ib) and coated with poly(acrylamide) (poly-AAm) hydrogel polymer using two consecutive steps: an electrospinning process followed by photopolymerization of AAm. Coated and non-coated CANF formulations were characterized by several microscopic and spectroscopic techniques to evaluate their physicochemical properties. An analysis of the kinetic release profile of Ib showed noticeable differences due to the presence or absence of the poly-AAm hydrogel polymer. Poly-AAm coating facilitated a constant release rate of drug as opposed to a more conventional burst release. The non-coated CANFs showed low cumulative drug release concentrations (ca. 35 and 83% at 5 and 10% loading, respectively). Conversely, poly-AAm coated CANFs were found to promote the release of drug (ca. 84 and 99.8% at 5 and 10% loading, respectively). Finally, the CANFs were found to be superbly cytocompatible.

Use of ibuprofen sustained release for treating osteoarthritic pain: findings from 15 general medical practices in Egypt

Purpose

Ibuprofen sustained release (SR) has been shown to provide effective symptomatic pain relief in chronic arthritic conditions such as osteoarthritis in European and US patient populations. Few studies have been conducted in other patient populations. A 4-week prospective multicenter open-label observational study was designed to explore and describe the combined effect of ibuprofen SR and standard medical care in patients suffering from osteoarthritis in 15 general medical practices in Egypt.

Patients and methods

In total, 519 patients were prescribed ibuprofen SR 2 ×800 mg once daily for 4 weeks.

Results

Ibuprofen SR combined with standard medical care significantly improved day and night pain, with 99.4% of the patients reporting improvement. The treatment reduced the symptom severity of joint tenderness/stiffness and the duration of morning stiffness, and allowed more patients to carry out normal activities. Overall compliance with the prescribed ibuprofen SR regimen was 98.6%. Ibuprofen SR was generally well tolerated with no serious adverse events reported during the study. There was no increase in blood pressure or heart rate.

Conclusion

The combined treatment provided effective relief of pain in patients with osteoarthritis in a large real-life general medical practice setting in Egypt. Owing to its convenient once-daily dosing regimen, ibuprofen SR may enhance patient compliance.

Influence of age on the enantiomeric disposition of ibuprofen in healthy volunteers

AIMS

To determine the influence of age on the enantioselective disposition of ibuprofen in humans.

METHODS

Healthy young (n = 16; aged 20-36 years) and elderly (n = 16; aged 66-84 years) volunteers were given a 400-mg oral dose of racemic ibuprofen, and blood and urine samples were collected for 24 h post drug administration. Serum concentrations, total and free, and urinary excretion of both enantiomers of ibuprofen together with the urinary excretion of the stereoisomers of the two major metabolites of the drug, both free and conjugated, were determined by high-performance liquid chromatography.

RESULTS

Ageing had little effect on the distribution and metabolism of R-ibuprofen, unbound clearance of the R-enantiomer via inversion being approximately two-fold that via noninversion mechanisms in both age groups. In contrast, the free fraction of S-ibuprofen was significantly greater [33%; young 0.48 +/- 0.10%; elderly 0.64 +/- 0.20%] mean difference -0.16; 95% confidence interval (CI) -0.05, -0.27; P < 0.01; and the unbound clearance of the drug enantiomer was significantly lower (28%; young 15.9 +/- 2.2 l min-1; elderly 11.5 +/- 4.1 l min-1; mean difference 4.4; 95% CI 2.12, 6.68; P < 0.001) in the elderly. The metabolite formation clearances of S-ibuprofen via glucuronidation, and oxidation at the 2- and 3- positions of the isobutyl side chain decreased by 24, 28 and 30%, respectively, in the elderly compared with the young, the differences between the two age groups being significant in each case (P < 0.05).

CONCLUSIONS

Following administration of racemic ibuprofen age-associated stereoselective alterations in drug disposition have been observed, with the elderly having increased free concentrations and lower unbound clearance of the S-enantiomer in comparison with the young. In contrast, the handling of the R-enantiomer is essentially unaltered with age. The results of this study indicate that the elderly have an increased exposure to the active ibuprofen enantiomer and thus some caution may be required when using this drug in this age group.

Ibuprofen and diclofenac sodium in the treatment of osteoarthritis: a comparative trial of two once-daily sustained-release NSAID formulations

An investigator-blind, parallel-group, multicentre study was undertaken to compare the efficacy and tolerability of once-daily, sustained-release (s-r) ibuprofen and diclofenac sodium in patients (mean age 59.8 years) suffering from painful osteoarthritis affecting chiefly the knee and/or hip. Patients attending eight Swiss centres received either two s-r tablets of ibuprofen (daily dose 1600 mg; n = 30) or a single s-r diclofenac 100 mg tablet (n = 31) each evening for 21 days. Clinical assessments were performed prior to initiating therapy and after 7 and 21 days of treatment. Both treatments were efficacious, but statistically significant differences in favour of s-r ibuprofen were observed for the principal measure of efficacy, the investigator's assessment of the overall change in clinical condition; by Day 21, 37% of ibuprofen-treated patients vs 10% of diclofenac-treated patients were 'much improved' (p = 0.04). Patients' assessments of the efficacy of their treatment also favoured s-r ibuprofen at Day 7 for the relief of night pain (p = 0.048), at Day 21 for alleviation of day pain (p = 0.006) and for the ability to carry out normal activities (p = 0.01), and at both Days 7 and 21 for quality of sleep (p = 0.04 and 0.03, respectively). The patients' overall opinion of treatment was also significantly in favour of s-r ibuprofen, which was rated 'good or excellent' by 80% (24/30), compared with only 38% of patients (11/29) receiving s-r diclofenac sodium (p = 0.002). Two patients (6%) receiving s-r diclofenac sodium ceased treatment owing to dizziness and severe diarrhoea, respectively; there were no withdrawals in the ibuprofen-treated group. Ten (32%) patients in the s-r diclofenac group reported a total of 12 adverse events (mostly gastrointestinal in nature), compared with three (10%) patients in the s-r ibuprofen group who reported only three events (abdominal pain, insomnia and constipation). In conclusion, although both NSAID treatments improved the clinical condition of patients with painful osteoarthritis, statistically significant differences in favour of once-daily s-r ibuprofen (1600 mg) were demonstrated in terms of efficacy, indicating a potential therapeutic advantage for this formulation. Ibuprofen was also better tolerated than diclofenac sodium (100 mg/day), the latter being associated with gastrointestinal side effects in a significant proportion of patients. Sustained-release ibuprofen (Brufen Retard) thus represents an important addition to the available therapeutic armamentarium of once-daily NSAID formulations.