Pharmacokinetics of Dexketoprofen Trometamol in Healthy Volunteers After Single and Repeated Oral Doses

A Physiologically Based Pharmacokinetic Model for Studying the Biowaiver Risk of Biopharmaceutics Classification System Class I Drugs With Rapid Elimination: Dexketoprofen Trometamol Case Study

Biowaiver based on the biopharmaceutics classification system (BCS) has been widely used in the global market for the approval of new generic drug products to avoid unnecessary in vivo bioequivalence (BE) studies. However, it is reported that three out of four formulations of dexketoprofen trometamol (DEX) tablets (BCS class I drug) failed the first BE study. The aim of this study was to determine whether the current biowaiver standard is reasonable for DEX. Thus, we successfully established a physiologically based pharmacokinetic (PBPK) model for DEX and examined the effects of dissolution, permeability, and gastric emptying time on DEX absorption under BCS-based biowaiver conditions using sensitivity analyses. Parameter sensitivity analysis showed that the dissolution rate in pH 1.2 media, permeability, and liquid gastric emptying time were sensitive parameters of C_max. Therefore, gastric emptying variation was introduced into the PBPK model, and virtual BE studys were conducted on original research formulation and the formulation of the boundary dissolution rate (f2 = 50) prescribed by the biowaiver guideline. The virtual BE results showed dissolution rate changes within the biowaiver range will not cause high non-BE ratio, indicate waive of DEX generic drugs would not lead the risk of C_max when generic products satisfy the requirements of biowaiver guideline. However, the effect of excipients on gastric emptying as a sensitive factor needs to be further studied when the rapid elimination of BCS class I drug is biowaived.

A new liquid phase microextraction method-based reverse micelle for analysis of dexketoprofen in human plasma by HPLC-DAD

A new liquid phase microextraction method was developed by used reverse micelle-based coacervates as microextraction agents for the separation of dexketoprofen (DKT) from human plasma before its determination by high-performance liquid chromatography with photodiode-array detection (HPLC-DAD). The change in the concentration of dexketoprofen in the plasma of the male and female patients was successfully monitored by using this method. The proposed method involves the use of reverse micelles of decanoic acid (DA) are dispersed in tetrahydrofuran (THF) and aqueous system. After addition of the DA and THF to the aqueous sample phase, the formation of micelles of nano and molecular size was observed in an ultrasonic bath. The solution was centrifuged, and the DKT extracted into the DA phase was analyzed by HPLC-DAD. Some analytical parameters that important in the developed procedure were examined in detail. The limit of detection (LOD), the limit of quantification (LOQ), the intraday, and inter day relative standard deviation (RSD, %) of the developed method in the plasma sample were found to be 12.8 ng mL−1, 38.8 ng mL−1, 1.7 and 3.9%, respectively. Additional/recovery studies were performed in plasma samples with proposed method, and quantitative recoveries were obtained in the range of 97–100%. The developed microextraction method was applied to human plasma that taken from volunteer patients for the determination of DKT.

Graphical abstract

Frovatriptan plus dexketoprofen in the treatment of menstrually related migraine: an open study

At least 50 % of female migraineurs experience migraine associated with the perimenstrual period, even though they may also suffer from attacks at other times of the cycle (menstrually related migraine, MRM). MRM attacks tend to be longer and more intense than those arising in other phases of the menstrual cycle, and are often aggravated by more pronounced vegetative phenomena. In this open preliminary trial, we tested the efficacy of associating frovatriptan and dexketoprofen for the treatment of an acute attack of MRM, diagnosed according to the criteria of the International Headache Society, in 24 patients between 19 and 45 years of age (mean 31.33 ± 7.33). Twenty-one of them completed the study. Pain relief was achieved by 76 % of patients at 2 h and by 86 % at 4 h. A pain-free state was achieved by 48 % at 2 h and by 62 % at 4 h from taking the product. A pain-free state at 24 h was present in 76 % of MRM sufferers, 33 % of whom showed a sustained pain-free state at 24 h. A rescue medication was needed by eight patients. While decidedly encouraging, the data of this study obviously need confirmation with double blind studies involving a greater number of patients.

Comparison of frovatriptan plus dexketoprofen (25 mg or 37.5 mg) with frovatriptan alone in the treatment of migraine attacks with or without aura: a randomized study

BACKGROUND

Drugs for migraine attacks include triptans and NSAIDs; their combination could provide greater symptom relief.

METHODS

A total of 314 subjects with history of migraine, with or without aura, were randomized to frovatriptan 2.5 mg alone (Frova), frovatriptan 2.5 mg + dexketoprofen 25 mg (FroDex25) or frovatriptan 2.5 mg + dexketoprofen 37.5 mg (FroDex37.5) and treated at least one migraine attack. This was a multicenter, randomized, double-blind, parallel-group study. The primary end point was the proportion of pain free (PF) at two hours. Secondary end points were PF at one and four hours, pain relief (PR) at one, two, four hours, sustained PF (SPF) at 24 and 48 hours, recurrence at 48 hours, resolution of nausea, photophobia and phonophobia at two and four hours, the use of rescue medication and the judgment of the treatment.

RESULTS

The results were assessed in the full analysis set (FAS) population, which included all subjects randomized and treated for whom at least one post-dose intensity of headache was recorded. The proportions of subjects PF at two hours (primary end point) were 29% (27/93) with Frova compared with 51% (48/95 FroDex25 and 46/91 FroDex37.5) with each combination therapies ( P < 0.05). Proportions of SPF at 24 hours were 24% (22/93) for Frova, 43% (41/95) for FroDex25 ( P < 0.001) and 42% (38/91) for FroDex37.5 ( P < 0.05). SPF at 48 hours was 23% (21/93) with Frova, 36% (34/95) with FroDex25 and 33% (30/91) with FroDex37.5 ( P = NS). Recurrence was similar for Frova (22%, 6/27), FroDex25 (29%, 14/48) and FroDex37.5 (28%, 13/46) ( P = NS), meaning a lack of improvement with the combination therapy. Statistical adjustment for multiple comparisons was not performed. No statistically significant differences were reported in the occurrence of total and drug-related adverse events. FroDex25 and FroDex37.5 showed a similar efficacy both for primary and secondary end points. There did not seem to be a dose response curve for the addition of dexketoprofen.

CONCLUSION

FroDex improved initial efficacy at two hours compared to Frova whilst maintaining efficacy at 48 hours in this study. Tolerability profiles were comparable. Intrinsic pharmacokinetic properties of the two single drugs contribute to this improved efficacy profile.

Analgesic properties of dexketoprofen trometamol

SUMMARY Dexketoprofen trometamol is the dextrorotary enantiomer of the NSAID ketoprofen formulated as a tromethamine salt. The purpose of administering 50% of the racemic mixture is to keep the same analgesic and anti-inflammatory effect while reducing the adverse events due to both enantiomers. This article describes the pharmacological properties and evaluates the analgesic effects of dexketoprofen trometamol reported in acute and chronic pain conditions. The main conclusions are that dexketoprofen trometamol appears as effective as the double dose of the racemic drug. However, the reduction of adverse effects still has to be demonstrated. In addition, the formulation as tromethamine salt appears beneficial regarding fast onset of analgesia in acute pain conditions.

Evidence for a central mechanism of action of S-(+)-ketoprofen

It has been observed that some non-steroidal anti-inflammatory drugs (NSAIDs) may act through several mechanisms, in addition to central inhibition of prostaglandin synthesis. These other mechanisms include the L-arginine-nitric oxide (L-arginine-NO) pathway, as well as endogenous opiate and serotonergic mechanisms. Some of these mechanisms can explain the efficacy of NSAIDs in chronic pain conditions such as rheumatoid arthritis. The present study was designed to elucidate the involvement of the above pathways/mechanisms in the antinociceptive effect of S-(+)-ketoprofen at supraspinal and spinal levels. S-(+)-ketoprofen induced dose-dependent antinociception in the pain-induced functional impairment model in the rat. The antinociceptive effect of S-(+)-ketoprofen was not altered by i.t. or intracerebroventricula (i.c.v.) pre-treatment with L-arginine (29.6 microg/site) and L-nitro-arginine-monomethylester (L-NAME) (21.1 microg/site) and neither was the effect of S-(+)-ketoprofen modified by the opiate antagonist, naloxone (1 mg/kg, s.c.). In marked contrast, both i.c.v. administration of the 5-hydroxytryptamine (5-HT)(1)/5-HT(2)/5-HT(7) receptor antagonist, methiothepin (1.5 microg/site), and i.t. administration of the 5-HT(3)/5-HT(4) receptor antagonist, tropisetron (0.9 microg/site), significantly inhibited the S-(+)-ketoprofen-induced antinociceptive effect. These data suggest that the antinociceptive response to S-(+)-ketoprofen involves serotoninergic mechanisms via both supraspinal 5-HT(1)/5-HT(2)/5-HT(7) receptors and 5-HT(3) receptors located at spinal level. A role of the L-arginine-NO and opiate systems in S-(+)-ketoprofen-induced antinociception in the pain-induced functional impairment model in the rat model seems unlikely.

Antinociception and the new COX inhibitors: research approaches and clinical perspectives

New generations of cyclooxygenase (COX) inhibitors are more potent and efficacious than their traditional parent compounds. They are also safer than the classic non-steroidal anti-inflammatory drugs (NSAIDs) and are starting to be used not only for low to moderate intensity pain, but also for high intensity pain. Three different strategies have been followed to improve the pharmacological profile of COX inhibitors: 1. Development of COX-2 selective inhibitors. This is based on the initial hypothesis that considered COX-2 as the enzyme responsible for the generation of prostaglandins only in inflammation, and, therefore, uniquely responsible for inflammation, pain and fever. Initial expectations gave rise to controversial results, still under discussion. The second generation of these compounds is being developed and should contribute to clarifying both their efficacy and the specific functions of the COX enzymes. 2. Modified non-selective COX inhibitors. Molecules like nitro-NSAIDs or tromethamine salt derivatives have been synthesized considering that both COX-1 and COX-2 are responsible for the synthesis of prostaglandins involved either in homeostatic functions or inflammation. Nitroaspirin, nitroparacetamol or dexketoprofen trometamol are some examples of molecules that are already showing an important clinical efficacy. The modifications performed in their structures seem to lower the unwanted side effects as well as to enhance their analgesic efficacy. 3. Combined therapy of classic NSAIDs with other drugs. This strategy looks for improvements in the incidence of adverse effects or to take advantage of the synergistic enhancement of their therapeutic effects. Some of the molecules resulting from these strategies are very valuable as therapeutic agents and open a wide range of possibilities in the treatment of high intensity pain, including neuropathic pain, and opiate sparing therapy.

Double-blind evaluation of short-term analgesic efficacy of orally administered dexketoprofen trometamol and ketorolac in bone cancer pain

The analgesic efficacy and safety of dexketoprofen trometamol (the active enantiomer of the racemic compound ketoprofen) (25mg q.i.d.) vs. ketorolac (10mg q.i.d.) was assessed in 115 patients with bone cancer pain included in a multicenter, randomized, double-blind, parallel group study. A level of >/=40 mm on the 100 mm visual analog scale (VAS) and >/=10 in the pain rating index were required for inclusion. At the end of treatment on day 7 (+1 day), mean values of VAS were 32+/-24 mm for dexketoprofen and 40+/-30 mm for ketorolac (P=0.12) but the pain rating index was significantly lower in patients given dexketoprofen (8.5+/-2.3 vs. 9.7+/-2.9, P=0.04). Moreover, most of the patients reached a pain intensity difference from baseline >/=20 mm (75% of patients for dexketoprofen and 65% of patients for ketorolac). Around half of patients in both treatments had a pain intensity <30 mm on VAS at the end of treatment (55% for dexketoprofen and 47% for ketorolac). In the overall assessment of efficacy, a higher percentage of both patients and physicians rated dexketoprofen as 'quite effective' or 'very effective' compared to ketorolac. The percentage of patients withdrawn from the study for any reason as well as for insufficient therapeutic effect or due to adverse events was lower in the dexketoprofen group than in the ketorolac group. Treatment-related adverse events occurred in 16% of patients given dexketoprofen and in 24% given ketorolac. Serious adverse events occurred in 3.5% of patients from both groups but only one case of gastrointestinal hemorrhage was considered related to ketorolac. We conclude that dexketoprofen trometamol 25 mg q.i.d. oral route is a good analgesic therapy in the treatment of bone cancer pain, comparable to ketorolac 10 mg q.i.d., with a good tolerability profile.

Comparison of dexketoprofen trometamol and dipyrone in the treatment of renal colic

BACKGROUND

Nonsteroidal anti-inflammatory drugs (NSAIDs) have been widely used for pain relief in patients with renal colic. Dexketoprofen trometamol is an NSAID that has demonstrated good analgesic efficacy and a good safety profile after oral administration in different models of acute and chronic pain.

OBJECTIVE

To assess the analgesic efficacy and safety of single intramuscular doses of dexketoprofen trometamol (25 and 50mg) compared with dipyrone (2g) in moderate to severe pain due to renal colic.

STUDY DESIGN

Multicentre, randomised, double-blind, parallel-group study.

PATIENTS

PATIENTS of both sexes aged 18-70 years with a diagnosis of renal colic were eligible for randomisation if they presented with at least moderate pain as assessed by visual analogue scale (VAS) scoring ≥40mm on a scale of 100mm immediately before study drug administration.

METHODS

Assessment of analgesic efficacy was done using standard pain intensity and pain relief scales. Total scores from baseline to 6 hours after study drug administration were calculated for the sum of pain intensity differences relative to baseline (SPID), sum of analogue pain intensity differences relative to baseline (SAPID) and total pain relief scores (TOTPAR) as primary efficacy endpoints. Secondary efficacy and safety variables were also analysed.

RESULTS

A total of 333 patients (dexketoprofen 25mg, n = 112; dexketoprofen 50mg, n = 113; dipyrone 2g, n = 108) were included in the study. No significant differences were found between the treatment groups with regard to SPID (p = 0.797), SAPID (p = 0.852) and TOTPAR (p = 0.716). The time-effect course for pain intensity differences and pain relief showed significantly (p < 0.05) higher values for both doses of dexketoprofen trometamol compared with dipyrone during the first hour after treatment administration. More than 90% of the patients in all three groups achieved pain relief of at least 50% as compared with baseline. Similarly, over 70% of the patients in all three groups considered the received treatment as excellent or good in the overall assessment of efficacy at the end of the study. No dose-effect relationship was observed in this pain model between both doses of dexketoprofen trometamol. All three treatments were well tolerated, showing mostly mild to moderate adverse events.

CONCLUSION

Dexketoprofen trometamol is a good analgesic for the treatment of moderate to severe pain due to renal colic, with a good safety profile and an efficacy comparable to that of dipyrone. The significantly greater effect of dexketoprofen trometamol early after administration suggests a faster onset of action, which can be of paramount importance in this condition.

Oral dexketoprofen for pain treatment during diagnostic hysteroscopy in postmenopausal women

OBJECTIVE

To assess the efficacy of dexketoprofen (DEX) in reducing pain at different stages of the hysteroscopic procedure in comparison with local anaesthesia in menopausal women.

METHODS

Menopausal patients affected by uterine bleeding submitted to diagnostic hysteroscopy, were randomised to receive either 25 mg DEX tablet (n = 148) or intracervical injection of 5 ml mepivacaine 2% (n = 150). Pain suffered during the procedure itself and 30, 60, 120 min after, was scored on the 11 point Visual Analogic Scale, recorded and analysed.

RESULTS

No statistical difference were noted during the procedure itself in both groups of treatment. Patients treated with DEX has significantly less postoperative pain.

CONCLUSIONS

DEX is not superior to mepivacaine in reducing the discomfort of the procedure but does significantly reduce postoperative pain.

Effect of perioperative administration of dexketoprofen on opioid requirements and inflammatory response following elective hip arthroplasty

BACKGROUND

In this double-blind, randomized, placebo-controlled trial, the safety and analgesic efficacy of perioperative dexketoprofen were evaluated.

METHODS

Thirty ASA I or II patients undergoing elective hip arthroplasty were randomized to one of two groups. One group (D) received dexketoprofen 25 mg tds for 24 h before and 48 h after surgery; the second group (P) received placebo tablets at equivalent times. Hyperbaric 0.5% bupivacaine (17.5 mg if greater than 70 kg and 15 mg if less than 70 kg) and preservative-free morphine (0.6 mg) were administered intrathecally. Postoperatively, PCA was provided (bolus morphine sulphate 1 mg; lockout 5 min; no continuous infusion).

RESULTS

The two groups were similar in terms of age, gender, weight, height, ASA class, duration of operation, and level of sensory block on arrival to the recovery room. Groups were also similar in terms of blood loss, transfusion requirements, ventilatory frequency, and haemodynamic variables. According to visual analogue pain scores patients in group D experienced less pain at 15 h (P=0.02) postoperatively. Cumulative morphine consumption was also less in group D compared with group P at 6 (0.06 (0.2) vs 0.85 (1.4) mg, P=0.04) and 48 h postoperatively (10.1 (8) vs 26.2 (20) mg, P<0.01). Plasma interleukin 6 concentrations increased postoperatively to a significantly lesser extent in group D than in group P (P=0.02). Nausea and vomiting were less (P<0.01) in group D compared with group P at 18 h postoperatively. Sedation scores were less (P=0.03) in group D.

CONCLUSIONS

Perioperative administration of dexketoprofen 25 mg 8 hourly markedly improves analgesia and decreases opioid requirements (and associated adverse effects) following hip arthroplasty. It appears that this regimen decreases the postoperative pro-inflammatory response.

Pharmacokinetics of ketoprofen syrup in small children

Ketoprofen is a nonsteroidal anti-inflammatory drug with analgesic, anti-inflammatory, and antipyretic properties. Its pharmacokinetics has not been determined in small children. The objective here was to determine the pharmacokinetics of ketoprofen syrup, 0.5 mg/kg, in two groups of 10 children. Group 1 was from ages 6 months up to 2 years (7/10 younger than 1 year), and Group 2 was from ages 2 to 7 years. Venous blood samples were collected before drug administration and 0.5, 1, 2, 4, 6, 8, and 12 hours after. A validated HPLC method was used to determine plasma levels of ketoprofen. The lower limit of quantification was 0.02 microgram/ml of plasma. Ketoprofen syrup was absorbed rapidly, the plasma level reaching its maximum at 0.5 hours, with C0.5 hours = 3 micrograms/ml. The pharmacokinetics was similar between the two groups of children. The elimination half-life, 2.0 hours in Group 1 or 1.9 hours in Group 2, was similar to that reported in adults.