Chiral separation of ibuprofen and chiral pharmacokinetics in healthy chinese volunteers

Comparison of intravenous ibuprofen pharmacokinetics between Caucasian and Chinese populations using physiologically based pharmacokinetics modeling and simulation

BACKGROUND

Intravenous ibuprofen, a nonsteroidal anti-inflammatory drug, is widely used as an antipyretic and analgesic in adults and children. This study was designed to evaluate ethnic differences by comparing the pharmacokinetics of intravenous ibuprofen in Caucasian and Chinese populations using physiologically based pharmacokinetics (PBPK) modeling and simulation.

METHODS

A PBPK model for intravenous ibuprofen was developed in adults and children utilizing the Simcyp Simulator. The model was tested and verified against published literature and unpublished data obtained from the Caucasian adult population, Caucasian pediatric population and Chinese adult population.

RESULTS

The developed PBPK model could adequately pilot the pharmacokinetics of intravenous ibuprofen, and the major observed values were within the 90% prediction interval in both adults and children. Both folding errors of the maximum peak concentration (Cmax) and area under the concentration-time curve (AUC) were 1.5-fold less in the Caucasian and Chinese populations. In addition, no significant differences in weight-normalized Cmax and AUC were observed between the Caucasian and Chinese adult populations. Moreover, there were no obvious pharmacokinetic differences between the Caucasian and Chinese pediatric populations with intravenous infusion (10 minutes) of 10 mg/kg by age group.

CONCLUSION

This study indicates that the pharmacokinetic profile and the parameters of intravenous ibuprofen are analogous in Caucasian and Chinese populations, either adults or children. In addition, this study provides effective evidence that the dosing scheme of intravenous ibuprofen in Chinese children can remain the same as the regimen that the original company (Caldolor®) provided.

Chiral pharmacokinetics of ibuprofen enantiomers in Chinese preterm neonates with patent ductus arteriosus using a validated UHPLC-MS/MS method

Persistent patent ductus arteriosus (PDA) is generally observed in preterm neonates. Oral ibuprofen is the standard treatment for closing PDA in China. To investigate the chiral pharmacokinetics of ibuprofen enantiomers in Chinese premature infants with PDA, a simple, fast, and sensitive analytical enantioselective technology was developed with ultra-performance liquid chromatography (UPLC) - tandem mass spectrometry (MS/MS). Chromatographic separation of (R)-ibuprofen and (S)-ibuprofen was accomplished on a Lux® 3 µm Cellulose-3 (150 mm × 2.0 mm, 3 μm) at a flow rate of 0.2 mL/min within 6 min. UPLC separation was achieved by isocratic elution with a mobile phase consisting of formic acid:water (75:1000000, v/v) and acetonitrile:methanol (1:1, v/v). Only 50 µL of plasma samples were pre-treated with acetonitrile precipitation. Ibuprofen-d3 was used as an internal standard. The standard curves of both enantiomers were linear over a concentration range of 0.0500 μg/mL to 50.00 μg/mL. The method has been validated for selectivity, carryover effect, lower limit of quantification, precision, accuracy, matrix effect, extraction recovery, dilution integrity, and stability based on the existing guidelines of the National Medical Products Administration, the United States Food and Drug Administration, and the European Medicines Agency. This method has been successfully applied to investigate the pharmacokinetics of ibuprofen enantiomers in 9 preterm infants with PDA. Our results showed that a high chiral inversion ratio of (R)- to (S)-ibuprofen exists in Chinese preterm neonates. Further studies should be conducted to monitor drug concentration following oral administration of ibuprofen and to consider the effect of individual variations and ethnic differences in metabolizing enantiomers of ibuprofen in premature neonates with PDA.

A Validated Chiral LC–MS/MS Method for the Enantioselective Determination of (S)-(+)- and (R)-(-)-Ibuprofen in Dog Plasma: Its Application to a Pharmacokinetic Study

The purpose of this study was to develop a method for simultaneously separating ibuprofen enantiomers using electrospray ionization (ESI) liquid chromatography with tandem mass spectrometry (LC–MS/MS). LC–MS/MS was operated with negative ionization and multiple reaction monitoring modes; transitions were monitored at m/z of 205.1 > 160.9 for ibuprofen enantiomers, 208.1 > 163.9 for (S)-(+)-ibuprofen-d3 [internal standard 1 (IS1)], and 253.1 > 208.9 for (S)-(+)-ketoprofen (IS2), respectively. In a one-step liquid–liquid extraction, 10 μL plasma was extracted with ethyl acetate:methyl tertiary-butyl ether of 7:3. Enantiomer chromatographic separation was carried out with an isocratic mobile phase consisting of 0.008% formic acid in water–methanol (v/v) at a flow rate of 0.4 mL/min on a CHIRALCEL® OJ-3R column (150 × 4.6 mm, 3 µm). This method was fully validated for each enantiomer and results were in compliance with the regulatory guidelines of the U.S. Food and Drug Administration and the Korea Ministry of Food and Drug Safety. The validated assay was executed for nonclinical pharmacokinetic studies after oral and intravenous administration of racemic ibuprofen and dexibuprofen in beagle dogs.

Efficacy and Safety of NSAIDs in Infants: A Comprehensive Review of the Literature of the Past 20 Years

Non-steroidal anti-inflammatory drugs (NSAIDs) are commonly used in infants, children, and adolescents worldwide; however, despite sufficient evidence of the beneficial effects of NSAIDs in children and adolescents, there is a lack of comprehensive data in infants. The present review summarizes the current knowledge on the safety and efficacy of various NSAIDs used in infants for which data are available, and includes ibuprofen, dexibuprofen, ketoprofen, flurbiprofen, naproxen, diclofenac, ketorolac, indomethacin, niflumic acid, meloxicam, celecoxib, parecoxib, rofecoxib, acetylsalicylic acid, and nimesulide. The efficacy of NSAIDs has been documented for a variety of conditions, such as fever and pain. NSAIDs are also the main pillars of anti-inflammatory treatment, such as in pediatric inflammatory rheumatic diseases. Limited data are available on the safety of most NSAIDs in infants. Adverse drug reactions may be renal, gastrointestinal, hematological, or immunologic. Since NSAIDs are among the most frequently used drugs in the pediatric population, safety and efficacy studies can be performed as part of normal clinical routine, even in young infants. Available data sources, such as (electronic) medical records, should be used for safety and efficacy analyses. On a larger scale, existing data sources, e.g. adverse drug reaction programs/networks, spontaneous national reporting systems, and electronic medical records should be assessed with child-specific methods in order to detect safety signals pertinent to certain pediatric age groups or disease entities. To improve the safety of NSAIDs in infants, treatment needs to be initiated with the lowest age-appropriate or weight-based dose. Duration of treatment and amount of drug used should be regularly evaluated and maximum dose limits and other recommendations by the manufacturer or expert committees should be followed. Treatment for non-chronic conditions such as fever and acute (postoperative) pain should be kept as short as possible. Patients with chronic conditions should be regularly monitored for possible adverse effects of NSAIDs.

Enantioselective separation of nonsteroidal anti-inflammatory drugs with amylose tris(3-chloro-5-methylphenylcarbamate) stationary phase in HPLC with a focus on enantiomeric quality control in six pharmaceutical formulations containing racemic mixtures or single stereoisomers

In the present study, an accurate, rapid, and simple chiral HPLC-UV method with amylose tris(3-chloro-5-methylphenylcarbamate) as stationary phase was developed and applied for enantiomeric determination of six nonsteroidal anti-inflammatory drugs (NSAIDs) in the commercial pharmaceutical formulations, including (R,S)-ibuprofen, S-ibuprofen, (R,S)-ketoprofen, S-ketoprofen, S-naproxen, and (R,S)-loxoprofen sodium. Experiments on the influence of mobile phase composition, proportion of organic modifier, percentage of acid additives, and column temperature on enantioseparation were conducted to obtain the best separation condition. It was indicated that one mobile phase simply composed of acetonitrile-water (0.1% formic acid, v/v) at the proportion of 50:50 (v/v) with a flow rate of 0.6 ml/min at 22°C could simultaneously provide the excellent enantiomeric resolutions for all selected NSAIDs, which made the enantioseparation process more applicable and operable. The newly developed method was then applied for determination of NSAID enantiomers in pharmaceutical formulations containing racemic mixtures or single stereoisomers. Calibration curve of each enantiomer at the concentration of 5.0-100 ug/ml showed good linearity with the correlation coefficient above 0.9996. Satisfactory recovery (96.54-101.54%), good intra-day precision (RSD 0.52-1.46%), and inter-day precision (RSD 0.13-1.09%) were also obtained. The newly developed method was then applied for determination of NSAID enantiomers in pharmaceutical formulations containing racemic mixtures or single stereoisomers. Quantitative results of the commercial capsules and tablets demonstrated that the difference between the declared and measured values did not exceed 1.52%.

Enantiomer specific pharmacokinetics of ibuprofen in preterm neonates with patent ductus arteriosus

Aims

Racemic ibuprofen is widely used for the treatment of preterm neonates with patent ductus arteriosus. Currently used bodyweight‐based dosing guidelines are based on total ibuprofen, while only the S‐enantiomer of ibuprofen is pharmacologically active. We aimed to optimize ibuprofen dosing for preterm neonates of different ages based on an enantiomer‐specific population pharmacokinetic model.

Methods

We prospectively collected 210 plasma samples of 67 preterm neonates treated with ibuprofen for patent ductus arteriosus (median gestational age [GA] 26 [range 24–30] weeks, median body weight 0.83 [0.45–1.59] kg, median postnatal age [PNA] 3 [1–12] days), and developed a population pharmacokinetic model for S‐ and R‐ibuprofen.

Results

We found that S‐ibuprofen clearance (CL_S, 3.98 mL/h [relative standard error {RSE} 8%]) increases with PNA and GA, with exponents of 2.25 (RSE 6%) and 5.81 (RSE 15%), respectively. Additionally, a 3.11‐fold higher CL_S was estimated for preterm neonates born small for GA (RSE 34%). Clearance of R‐ibuprofen was found to be high compared to CL_S (18 mL/h [RSE 24%]), resulting in a low contribution of R‐ibuprofen to total ibuprofen exposure. Current body weight was identified as covariate on both volume of distribution of S‐ibuprofen and R‐ibuprofen.

Conclusion

S‐ibuprofen clearance shows important maturation, especially with PNA, resulting in an up to 3‐fold increase in CL_S during a 3‐day treatment regimen. This rapid increase in clearance needs to be incorporated in dosing guidelines by adjusting the dose for every day after birth to achieve equal ibuprofen exposure.

Single dose oral dexibuprofen [S(+)-ibuprofen] for acute postoperative pain in adults

BACKGROUND

This review is an update of a previously published review in The Cochrane Database of Systematic Reviews Issue 3, 2009 on single dose oral dexibuprofen (S(+)-ibuprofen) for acute postoperative pain in adults.Dexibuprofen is a non-steroidal anti-inflammatory drug (NSAID) licensed for use in rheumatic disease and other musculoskeletal disorders in the UK, and widely available in other countries worldwide. It is an active isomer of ibuprofen. This review sought to evaluate the efficacy and safety of oral dexibuprofen in acute postoperative pain, using clinical studies in patients with established pain, and with outcomes measured primarily over four to six hours, using standard methods. This type of study has been used for many decades to establish that drugs have analgesic properties.

OBJECTIVES

To assess the efficacy and adverse effects of single dose oral dexibuprofen for acute postoperative pain using methods that permit comparison with other analgesics evaluated in standardised studies using almost identical methods and outcomes.

SEARCH METHODS

Searches were run for the original review in 2009 and subsequent searches have been run in August 2013. We did not find any new published studies as a result of the updated search.We searched for randomised studies of dexibuprofen in acute postoperative pain in MEDLINE, EMBASE, and CENTRAL (The Cochrane LIbrary), and for clinical trial reports and synopses of published and unpublished studies from Internet sources.

SELECTION CRITERIA

Randomised, double blind, placebo-controlled clinical studies of oral dexibuprofen for relief of acute postoperative pain in adults.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed study quality and extracted data. We extracted pain relief or pain intensity data and converted it into the dichotomous outcome of number of participants with at least 50% pain relief over four to six hours, from which relative risk and number needed to treat to benefit (NNT) were calculated. Numbers of participants using rescue medication over specified time periods, and time to use of rescue medication, were sought as additional measures of efficacy. We collected information on adverse events and withdrawals.

MAIN RESULTS

New data were identified for this update in one unpublished trial synopsis (BR1160 1995) in addition to the single study (Dionne 1998) that was included in the original review. In both studies dexibuprofen gave high levels of response, with 51/96 (53%) participants experiencing at least 50% pain relief with dexibuprofen 200 mg and 35/50 (70%) with dexibuprofen 400 mg, compared with 75/147 (51%) with racemic ibuprofen 400 mg, and 12/62 (13%) with placebo. The numbers of participants was too small to calculate NNTs with any meaning. The median time to additional analgesic use was greater than four hours for all active therapies, but about two hours for placebo.Adverse events were generally of mild or moderate intensity and consistent with events normally associated with anaesthesia and surgery. There were no serious adverse events or deaths.Additional data did not alter the conclusions from the earlier review.

AUTHORS' CONCLUSIONS

The information from these two studies in acute postoperative pain suggested that dexibuprofen may be a useful analgesic, but at doses not very different from racemic ibuprofen, for which considerably more evidence exists.

Chiral pharmacokinetics of zaltoprofen in rats by HPLC with solid-phase extraction

We investigated the pharmacokinetic profile of (R)- and (S)-zaltoprofen (ZPF) in rats using rapid and selective liquid chromatography with solid-phase extraction (SPE). The ZPF enantiomers were extracted from a small volume of plasma (0.2 mL) by means of SPE using cartridges and were analyzed on a Chiralcel OJ-H (4.6 mm × 150 mm, 5 μm) column with ultraviolet detection at 244 nm. The lower limit of quantification of the ZPF enantiomers in plasma was 0.1μg/mL. The validated method was successfully applied to chiral pharmacokinetic studies of oral administration of racemic ZPF to rats. (S)-ZPF showed significantly higher AUC, T(max), and C(max) and a longer half-life than (R)-ZPF, indicating higher bioavailability of the (S)-isomer. A total of 8 samples (about 12% of the total number of samples) were selected for incurred sample reanalysis (ISR). The % difference between the re-assay concentrations and the original concentrations were all less than 15% of their mean values and met the acceptance criteria for ISR.

Efficient synthesis and chiral separation of 11C-labeled ibuprofen assisted by DMSO for imaging of in vivo behavior of the individual isomers by positron emission tomography

The pharmacological mechanisms focusing on chiral isomer of ibuprofen are not fully understood. Only the (S)-isomer of ibuprofen inhibits cyclooxygenases, which mediates the generation of prostanoids and thromboxanes. Consequently, (S)-isomers represent a major promoter of the anti-inflammatory effect, and the effects of the (R)-isomers have not been widely discussed. However, more recently, the cyclooxygenase-independent pharmacological effects of ibuprofen have been elucidated. Pharmacokinetic studies with individual isomers of ibuprofen by positron emission tomography should aid our understanding of the pharmacological mechanisms of ibuprofen. The efficient (11)C-labeling of ibuprofen for chiral separation via the TBAF-promoted α-[(11)C]methylation was achieved by using DMSO rather than THF as the reaction solvent. The robust production of the radiochemically labile (11)C-labeled ibuprofen ester was realized by the protective effect of DMSO on radiolysis. After intravenous injection of each enantiomer of [(11)C]ibuprofen, significantly high radioactivity was observed in the joints of arthritis mice when compared to the levels observed in normal mice. However, the high accumulation was equivalent between the enantiomers, indicating that ibuprofen is accumulated in the arthritic joints regardless of the expression of cyclooxygenases.

Ibuprofen-induced hypersensitivity syndrome

Ibuprofen is a widely used antipyretic and analgesic nonsteroidal antiinflammatory drug (NSAID). With the aging of the population, there will be a significant increase in the prevalence of painful degenerative and inflammatory rheumatic conditions. This increase likely will lead to a parallel increase in the use of NSAIDs, including ibuprofen. The primary effect of the NSAIDs is to inhibit cyclooxygenase (prostaglandin synthase), thereby impairing the ultimate transformation of arachidonic acid to prostaglandins, prostacyclin, and thromboxanes. Although in the majority of cases it is safe, this NSAID, ibuprofen, can produce an unpredictable, idiosyncratic, type B reaction that may pose a major concern in clinical practice. Type B reactions are known to occur in susceptible individuals. The true hypersensitivity reaction (HSR) is a systemic disease defined by the triad of fever, rash, and internal organ involvement that starts 1 day to 12 weeks after the initiation of therapy. HSR has limited the therapeutic use of many drugs, including ibuprofen. Hypersensitivity syndrome associated with ibuprofen is a host-dependent drug reaction that is idiosyncratic in nature. This reaction likely is caused by a combination of metabolic and immunologic factors. Immune mediated components, such as T-cell and their products cytokines and chemokines, can exacerbate cellular responses and create complex pathways that lead to a variety of clinical manifestations. Our review presents an ibuprofen-induced clinical manifestation of hypersensitivity syndrome and the necessity of wisely monitoring the patients clinically and by laboratory investigations when prescribing this drug.

Single dose oral dexibuprofen [S(+)-ibuprofen] for acute postoperative pain in adults

BACKGROUND

Dexibuprofen (S(+)-ibuprofen) is a non-steroidal anti-inflammatory drug (NSAID) licensed for use in rheumatic disease and other musculoskeletal disorders in the UK, and widely available in other countries worldwide. It is an active isomer of ibuprofen. This review sought to evaluate the efficacy and safety of oral dexibuprofen in acute postoperative pain, using clinical studies of patients with established pain, and with outcomes measured primarily over 6 hours using standard methods. This type of study has been used for many decades to establish that drugs have analgesic properties.

OBJECTIVES

To assess efficacy, duration of action, and associated adverse events of single dose oral dexibuprofen in acute postoperative pain in adults.

SEARCH STRATEGY

We searched Cochrane CENTRAL, MEDLINE, EMBASE and the Oxford Pain Relief Database for studies to May 2009.

SELECTION CRITERIA

Randomised, double blind, placebo-controlled clinical trials of oral dexibuprofen for relief of acute postoperative pain in adults.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed trial quality and extracted data. Pain relief or pain intensity data were extracted and converted into the dichotomous outcome of number of participants with at least 50% pain relief over 4 to 6 hours, from which relative risk and number needed to treat to benefit (NNT) were calculated. Numbers of participants using rescue medication over specified time periods, and time to use of rescue medication, were sought as additional measures of efficacy. Information on adverse events and withdrawals were collected.

MAIN RESULTS

In the single included study, both S(+)-ibuprofen (dexibuprofen, an active isomer of ibuprofen) 200 mg and 400 mg gave high levels of response, with 31/51 (61%) and 35/50 (70%) respectively having at least 50% pain relief over 4 to 6 hours, compared with 2/25 (8%) with placebo. The median time to additional analgesic use was 5.8 hours, 6.1 hours, and 1.8 hours respectively. The numbers of participants was too small to calculate NNTs with any meaning.

AUTHORS' CONCLUSIONS

The information from the single trial in acute postoperative pain suggests it to be a useful analgesic, but at doses not very different from racemic ibuprofen.