A New Approach in Lipase-Octyl-Agarose Biocatalysis of 2-Arylpropionic Acid Derivatives.

The use of lipase immobilized on an octyl-agarose support to obtain the optically pure enantiomers of chiral drugs in reactions carried out in organic solvents is a great challenge for chemical and pharmaceutical sciences. Therefore, it is extremely important to develop optimal procedures to achieve a high enantioselectivity of the biocatalysts in the organic medium. Our paper describes a new approach to biocatalysis performed in an organic solvent with the use of CALB-octyl-agarose support including the application of a polypropylene reactor, an appropriate buffer for immobilization (Tris base-pH 9, 100 mM), a drying step, and then the storage of immobilized lipases in a climatic chamber or a refrigerator. An immobilized lipase B from Candida antarctica (CALB) was used in the kinetic resolution of (R,S)-flurbiprofen by enantioselective esterification with methanol, reaching a high enantiomeric excess (eep = 89.6 ± 2.0%). As part of the immobilization optimization, the influence of different buffers was investigated. The effect of the reactor material and the reaction medium on the lipase activity was also studied. Moreover, the stability of the immobilized lipases: lipase from Candida rugosa (CRL) and CALB during storage in various temperature and humidity conditions (climatic chamber and refrigerator) was tested. The application of the immobilized CALB in a polypropylene reactor allowed for receiving over 9-fold higher conversion values compared to the results achieved when conducting the reaction in a glass reactor, as well as approximately 30-fold higher conversion values in comparison with free lipase. The good stability of the CALB-octyl-agarose support was demonstrated. After 7 days of storage in a climatic chamber or refrigerator (with protection from humidity) approximately 60% higher conversion values were obtained compared to the results observed for the immobilized form that had not been stored. The new approach involving the application of the CALB-octyl-agarose support for reactions performed in organic solvents indicates a significant role of the polymer reactor material being used in achieving high catalytic activity.

Effectiveness and Adherence Rate of S-flurbiprofen Plaster for the Pain Management of Patients With Moderate and End-Stage Knee Osteoarthritis.

BACKGROUND: S-flurbiprofen plaster (SFPP) is highly skin permeable and represents a new conservative treatment for knee osteoarthritis (KOA) that can attain considerably higher concentrations in the synovium than topical flurbiprofen. To date, no study has investigated the efficacy and adherence rate of SFPP in patients with end-stage KOA. This study aimed to compare the effectiveness and adherence rate of SFPP for pain management in patients with moderate and end-stage KOA. METHODS: This retrospective study included a total of 118 patients with KOA (Kellgren-Lawrence classification grades II (n = 29), III (n = 32), and IV (n = 57)). The difference in SFPP use rate, adverse drug reactions rate, whether 50% pain relief occurred, and the percentage of patients who underwent surgical treatment were calculated. RESULTS: The overall SFPP use rate at one year was 61.0% (88.1% at less than one month, 79.7% at three months, and 61.0% at six months), with no significant differences among Kellgren-Lawrence grade II, III, and IV groups (p = 0.538). Adverse drug reactions such as skin rash (n = 23), skin irritation (n = 8), and gastrointestinal disorders (n = 2) were observed. The one-year SFPP use rate was significantly lower in patients in whom these side effects occurred but did not decrease in patients in whom only a skin rash occurred. Overall, 19 patients underwent surgery after discontinuation of SFPP use. Surgery was statistically selected more by the "over 71 years of age" group (p = 0.038) and the "ineffective" group (p = 0.007). CONCLUSION: SFPP exerts a comparable therapeutic effect even in end-stage KOA and may be an effective treatment option. Even if patients have end-stage KOA, there are cases in which the patient's background does not allow for surgery positively, such as high perioperative risk or desire for conservative treatment. In such cases, SFPP may be an effective treatment option worth trying.

Discovery of (S)-flurbiprofen-based novel azine derivatives as prostaglandin endoperoxide synthase-II inhibitors: Synthesis, in-vivo analgesic, anti-inflammatory activities, and their molecular docking.

The anti-inflammatory and analgesic drugs currently used are associated with several adverse effects and found to be highly unsafe for long-term use. Currently, nineteen novel bis-Schiff base derivatives (1-19) of flurbiprofen have been designed, prepared and assessed for in-vivo analgesic, anti-inflammatory and in vivo acute toxicity evaluation. The structures of the acquired compounds were deduced through modern spectroscopic techniques including HR-ESI-MS, 13C-, and 1H NMR. Amongst the series, compounds 7, 9, and 10 attributed potent activities with 93.89, 92.50, and 90.47% decreased edema, respectively compared to flurbiprofen (90.01%), however, compounds 11 and 15 exhibited significant activity of 90.00% decrease. Out of them, fourteen compounds (1-6, 8, 12-14, and 16-19) displayed good activity in the range of 68.96-86.95%. In case of an analgesic study, all the derivatives significantly (p 0.001) increased the pain threshold time particularly compound 7 had the best analgesic effect (24 ± 2.08 s) in comparison with flurbiprofen (21.66 ± 2.02 s) using hot plate test. Similarly, in the acetic acid-induced writhing test, compound 7 determined a potent inhibitory effect (60.47 %) close to flurbiprofen (59.28%). All the synthesized derivatives were found safe up to the dose of 30 mg/kg, in acute toxicity study. On a molecular scale, the synthesized compounds were modeled through a ligand-based pharmacophore study and molecular docking to have insight into the different possible interactions leading to high inhibition levels against the COX-2 enzyme.

Comparison of in vivo pharmacokinetic behaviors of R- and S-flurbiprofen after intravenous injection of flurbiprofen axetil.

Flurbiprofen axetil (FA) is a prodrug of flurbiprofen (FP), and it is hydrolyzed to the active FP by carboxylesterase in plasma after intravenous injection. The pharmacological action of FP is closely related to its chirality, and S-FP shows better analgesic effects than R-FP. Therefore, it is of great significance to compare the in vivo pharmacokinetic behaviors of R-FP and S-FP. In this study, we designed a sensitive high performance liquid chromatography-tandem mass spectrometry method and used CHIRALPAK-IG3 column for chiral separation to quantify the concentrations of R-FP and S-FP in rat plasma. The results show that this method can accurately and effectively analyze the contents of R-FP and S-FP in plasma. In addition, the systemic exposure was approximately 3.09-folds for the S-FP compared with the R-FP following intravenous administration of the FA to rats at a single dose of 4.5 mg/kg. More importantly, the clearance rate of S-FP is significantly smaller than that of R-FP. Therefore, the development of S-FA injectable emulsion for clinical treatment of postoperative pain is very necessary.

Comparison of efficacy and safety in the combination therapies of duloxetine and S-flurbiprofen plaster, and of duloxetine and conventional NSAIDs for chronic pain in patients with osteoarthritis (OASIS DUAL study).

The purpose of this study is to compare the efficacy and safety of pharmacotherapies for chronic pain due to osteoarthritis (OA) between a group with duloxetine (DLX) and S-flurbiprofen plaster (SFPP) (the SFPP group) and a group with DLX and conventional non-steroidal anti-inflammatory drugs (NSAIDs) (the control group). The subjects were 49 patients (17 men and 32 women). The evaluation of factors associated with treatment termination due to symptoms improvement showed that significantly more women terminated treatment than did men, and significantly more members of the SFPP group terminated treatment than did members of the control group. The visual analogue scale (VAS) score in the SFPP group was significantly improved from 6.6 ± 1.7 before treatment to 3.6 ± 2.1 one month later and showed significant difference until nine months later. The VAS score in the control group was significantly improved from 6.7 ± 1.9 to 4.1 ± 2.8 one month later. The VAS score improvement rate was significantly higher in the SFPP group than in the control group, suggesting that the DLX-SFPP combination had higher efficacy than the DLX-conventional NSAIDs combination. The incidence of adverse drug reactions was 55% in the SFPP group, which is not significantly different from 50% incidence in the control group. The treatment discontinuation rate due to adverse drug reactions, however, was 60% in the control group and 19% in the SFPP group. It was suggested that the efficacy and safety of the DLX-SFPP combination for chronic pain due to OA are equal to or higher than that of the DLX-conventional NSAIDs combination.

Bio-Oriented Synthesis of Novel (S)-Flurbiprofen Clubbed Hydrazone Schiff's Bases for Diabetic Management: In Vitro and In Silico Studies.

A new series of (S)-flurbiprofen derivatives 4a-4p and 5a-5n were synthesized with different aromatic or aliphatic aldehydes and ketones to produce Schiff's bases and their structures were confirmed through HR-ESI-MS, 1H, and 13C-NMR spectroscopy. The α-glucosidase inhibitory activities of the newly synthesized compounds were scrutinized, in which six compounds 5k, 4h, 5h, 4d, 4b, and 5i showed potent inhibition in the range of 0.93 to 10.26 µM, respectively, whereas fifteen compounds 4c, 4g, 4i, 4j, 4l, 4m, 4o, 4p, 5c, 5d, 5j, 5l, 5m, 5n and 1 exhibited significant inhibitory activity with IC50 in range of = 11.42 to 48.39 µM. In addition, compounds 5g, 5f, 4k, 4n, and 4f displayed moderate-to-low activities. The modes of binding of all the active compounds were determined through the molecular docking approach, which revealed that two residues, specifically Glu277 and His351 are important in the stabilization of the active compounds in the active site of α-glucosidase. Furthermore, these compounds block the active site with high binding energies (-7.51 to -3.36 kcal/mol) thereby inhibiting the function of the enzyme.

Comparison of percutaneous permeation profiles of flurbiprofen enantiomers.

Flurbiprofen is clinically effective for the treatment of acute or long-term rheumatoid arthritis and osteoarthritis. Studies showed that S-flurbiprofen had better anti-inflammatory effect than R-flurbiprofen. As flurbiprofen racemates are usually used in the form of transdermal preparations, such as Flurbiprofen Cataplasms (Zepolas), it is of great significance to investigate the percutaneous permeation profiles of flurbiprofen enantiomers for considering whether it is necessary to develop the transdermal preparation with single optical enantiomer. Taking the economy into consideration, the flurbiprofen enantiomers as the mode drug and the CHIRALPAKAAGP column we had as instrument were used to perform the following experiments. On the basis of experiences provided by predecessors, we made some improvements to the analytical conditions, and method validation was developed to verify the feasibility of the method. The results showed that the established method could be used to analyze the percutaneous permeation profiles of flurbiprofen enantiomers in the flurbiprofen cataplasms accurately and effectively, and the percutaneous permeation profiles of flurbiprofen enantiomers had no significantly difference no matter under what conditions (P > 0.05).

Efficacy and safety of S-flurbiprofen plaster in knee osteoarthritis patients: A 2-week randomized controlled Phase III clinical trial compared to diclofenac gel.

AIM: S-flurbiprofen plaster (SFPP) is a novel topical nonsteroidal anti-inflammatory drug (NSAID) patch. This study aimed to assess the efficacy and safety of SFPP in knee osteoarthritis (OA) patients compared to diclofenac gel. METHODS: This study was a multicenter, randomized, active-controlled, open-label, non-inferiority phase III trial. There were 311 enrolled patients treated by SFPP or diclofenac gel for 2 weeks. The primary efficacy outcome was the knee pain when rising from the specially arranged chair assessed by visual analog scale (rVAS). The other efficacy outcomes were clinical symptoms, pain on walking, global assessment by both investigator and patient, and use/non-use of the rescue drugs during the treatment period. Adverse events (AEs) were evaluated as the safety outcome. RESULTS: The least-squares mean (95% CI) of ΔrVAS at the end of the study was 41.52 (39.16-43.88) mm in the SFPP group and 36.01 (33.69-38.33) mm in the diclofenac gel group, with a between-group difference of 5.51 (2.20-8.82), indicating non-inferiority. There were statistically significant differences between the groups in rVAS, clinical symptoms, pain on walking, and the global assessment by both investigator and patient. The incidence rate of AEs in the SFPP group was 5.8%, and there was no statistically significant difference from that in the diclofenac gel group (5.2%). Most of the AEs were mild, and no AE led to discontinuation. CONCLUSION: Non-inferiority of SFPP to diclofenac gel was demonstrated in the efficacy for pain on rising from a chair. SFPP was also well-tolerated in knee OA patients.

Treatment Efficacy of Single Topical NSAID (S-Flurbiprofen Plaster) for Knee Symptoms and Locomotive Dysfunction in Knee Osteoarthritis Patients.

OBJECTIVE: The aim of this study was to demonstrate the non-inferiority of S-flurbiprofen plaster (SFPP) monotherapy for treating knee osteoarthritis compared with the combination of conventional oral and topical non-steroidal anti-inflammatory drugs (NSAIDs). METHODS: A total of 222 participants (114, SFPP group; 108, control group) were treated for 4 weeks. The primary endpoint was the change in the degree of pain felt while rising from a chair after 2 and 4 weeks of treatment as determined using the visual analog scale (VAS) . The secondary endpoint was the change in functional scores and test results. Safety was evaluated in terms of the adverse effects. RESULTS: The VAS score significantly decreased in both groups after 2 and 4 weeks of treatment. Non-inferiority in the VAS score was established only at 2 weeks. There were no significant differences in the secondary endpoints between the groups. Skin disorders were more frequent in the SFPP group; however, there was no difference in gastrointestinal (GI) adverse effects. CONCLUSIONS: The therapeutic efficacy of SFPP monotherapy for knee OA, with respect to changes in the VAS, was not shown to be non-inferior to conventional treatment at 4 weeks; however, non-inferiority was established at 2 weeks. The functional improvement in the SFPP group was comparable to that of the control group. No severe GI adverse effects associated with SFPP administration were observed; however, it is necessary to pay more attention to the occurrence of skin disorders with SFPP than with conventional topical NSAIDs.

The Comparison of Plasma and Cerebrospinal Fluid R(-)- and S(+)-Flurbiprofen Concentration After Intravenous Injection of Flurbiprofen Axetil in Human Subjects.

Background: Flurbiprofen axetil is a prodrug that releases the active substance through enzymatic removal of the ester moiety. It is formulated through encapsulation in a lipid microsphere carrier, and widely used to treat perioperative pain. Here, we studied the distribution of R (-)- and S (+)-flurbiprofen in human plasma and cerebrospinal fluid (CSF) after intravenous injection of flurbiprofen axetil. Methods: A total of 70 adult patients undergoing elective lower limb surgery under spinal anesthesia were given a single intravenous injection of 100-mg flurbiprofen axetil. The patients were randomly assigned to 10 groups for plasma and CSF sampling at 10 time points (5-50 min) after subarachnoid puncture and before actual spinal anesthesia. R (-)- and S (+)-flurbiprofen and CSF/plasma ratio were determined by liquid chromatography-tandem mass spectrometry. Results: R (-)-flurbiprofen concentration ranged from 2.01 to 10.9 µg/mL in plasma and 1.46-34.4 ng/mL in CSF. S (+)-flurbiprofen concentration ranged from 1.18 to 10.8 µg/mL in plasma and from 2.53 to 47 ng/mL in CSF. In comparison to S (+)-flurbiprofen, R (-)-flurbiprofen concentration was significantly higher in plasma at all time points (p < 0.05) except at 30 or 40 min, and lower in CSF at all time points (p < 0.05) except at 10, 15 and 40 min. Analysis after correcting drug concentration for body mass index also revealed higher plasma and lower CSF R (-)-flurbiprofen concentration. In comparison to S (+)-flurbiprofen, AUC0-50 for R (-)-flurbiprofen was larger in plasma and smaller in CSF (p < 0.05 for both), and accordingly smaller CSF/plasma AUC0-50 ratio (p < 0.05). There was a positive correlation between R (-)-flurbiprofen concentration and S (+)-flurbiprofen concentration in plasma (r = 0.725, p < 0.001) as well as in CSF (r = 0.718, p < 0.001), and a negative correlation between plasma and CSF concentration of S (+)-flurbiprofen (r = -0.250, p = 0.037), but not R (-)-flurbiprofen. Conclusion: Distribution of R (-)- and S (+)-flurbiprofen in plasma and CSF differed significantly. Penetration of R (-)-flurbiprofen into the CNS was lower than S (+)-flurbiprofen.

An investigation on percutaneous permeation of flurbiprofen enantiomers: The role of molecular interaction between drug and skin components.

This work aimed to investigate skin permeation profiles of chiral flurbiprofen and clarify the molecular mechanism of transdermal permeation difference of enantiomers. The in vitro transdermal permeation of enantiomers through rat skin was studied by diffusion cells. Physicochemical parameters of model chiral drugs were determined. Molecular interaction between chiral flurbiprofen and ceramides of skin was investigated by FTIR, 13C NMR and molecular docking. The skin permeation mechanism of chiral drugs was characterized by ATR-FTIR, Raman spectra, DSC and molecular dynamic simulation. The results showed that the amount of the permeation and retention amount of (S)-flurbiprofen was 1.5 times over that of (R)-flurbiprofen. And it was proven that the difference was not induced by physicochemical properties but the molecular interaction between drug-skin components. (S)-flurbiprofen was easy to form stronger hydrogen bonding with -CONH group of skin lipids due to its steric configuration, which disturbed lipids arrangement more easily according to the results of ATR-FTIR (ΔνasCH2 = 1.00 cm-1), Raman spectra (ΔI2882/I2853 = 0.32) and the DSC (ΔTm stratum corneum = 11.75 °C). It was demonstrated more obvious effect on the second structure of keratin by ATR-FTIR study (Δ Amide I = 3.60 cm-1 and Δ Amide II = 3.38 cm-1). Better compatibility between (S)-flurbiprofen and lipids was confirmed quantificationally by thermodynamic analysis. In conclusion, the higher interaction between (S)-flurbiprofen and skin components, the higher skin permeation, which contributes to decrease the administration dose and increase the therapeutic effect.

Effect of Flurbiprofen and S-Flurbiprofen Patches on Multimodal Pain Management After Total Knee Arthroplasty: A Prospective Randomized Controlled Trial.

BACKGROUND: Total knee arthroplasty (TKA) is an established procedure for knee osteoarthritis. Multimodal analgesia is reportedly more effective for postoperative analgesia. We investigated the efficacy of 2 patches after TKA. METHODS: Seventy-nine knees that underwent unilateral TKA for osteoarthritis were included. Oral administration, local periarticular analgesic injection, and patches were adopted for pain management. The knees were randomly assigned to the flurbiprofen patch (FPP), S-flurbiprofen patch (SFPP), and control (no patch) groups. Patch treatment was continued for 14 days. Pain according to the visual analog scale, knee flexion angle, renal dysfunction, gastrointestinal injury, duration of hospitalization, dermatitis, and the rate of using additional oral nonsteroidal anti-inflammatory drugs were compared (from preoperative to postoperative day 14). RESULTS: The FPP, SFPP, and control groups included 29, 27, and 23 knees, respectively. Visual analog scale was lower in the FPP and SFPP groups than in the control group on days 1 and 3 (day 1: 24.4, 25.0, and 39.4, respectively; day 3: 25.5, 23.3, and 39.3, respectively). Knee flexion angle was larger in the SFPP group than in the control group on days 7 and 14 (day 7: 89.8° and 76.6°, respectively; day 14: 98.3° and 84.2°, respectively). Neither renal dysfunction nor gastrointestinal injury was confirmed. The duration of hospitalization did not differ among the groups. Dermatitis occurred only in the SFPP group. The rate of using additional oral nonsteroidal anti-inflammatory drugs was higher in the control group. CONCLUSION: Both patches were effective and safe as part of multimodal analgesia for postoperative TKA.

Analgesic effect of S (+)-flurbiprofen plaster in a rat model of knee arthritis: analysis of gait and synovial fluid prostaglandin E2 levels.

OBJECTIVES: We developed S (+)-flurbiprofen plaster (SFPP), a novel NSAID patch containing S (+)-flurbiprofen (SFP), a potent cyclooxygenase (COX) inhibitor. The purpose of this study was to assess efficacy of SFPP by analysing its effect on the gait disturbance and measuring the prostaglandin E2 (PGE2 ) production in synovial fluid in a rat model of knee arthritis. METHODS: Knee inflammation was induced in rats by intra-articular injection of a yeast suspension. Subsequently, an NSAID patch containing SFP, ketoprofen or loxoprofen was applied over the affected knee. Gait was assessed at 2, 4 and 6 h after application of the patch. The PGE2 concentration in the synovial fluid was measured after the gait assessment. KEY FINDINGS: Application of SFPP (0.125, 0.25, 0.5 or 1 mg/sheet) was followed by a decrease in the visual gait score at all the doses examined. In the case of the other two NSAID patches, only the ketoprofen patch (1 or 2 mg/sheet) and loxoprofen patch (5 mg/sheet) produced a decrease in the visual gait score. All of the NSAID patches decreased the PGE2 production in the synovial fluid. CONCLUSIONS: These results suggest the potential usefulness of SFPP as an analgesic patch in patients with inflammatory joint pain.

Mutual inversion of flurbiprofen enantiomers in various rat and mouse strains.

Flurbiprofen (F) is a nonsteroidal anti-inflammatory drug (NSAID) used therapeutically as the racemate of (R)-enantiomer and (S)-enantiomer. The inversion of RF to SF and vice versa was investigated in C57Bl/6 and SJL mice and Dark Agouti and Lewis rats. The enzyme α-methylacyl-CoA racemase (AMACR) is involved in the chiral inversion pathway that converts members of the 2-arylpropionic acid NSAIDs from the R-enantiomer to the S-enantiomer. We studied C57Bl/6 mice deficient in AMACR postulating that they should show reduced inversion of RF to SF. In line with the data of others in mice, (R)-inversion to (S)-inversion was relatively high in both the C57Bl/6 and SJL mice (fraction inverted, FI  = 37.7% and 24.7%, respectively). In contrast, in AMACR deficient mice, there was no measurable peak for SF after administration of RF. The results in both rat strains (Dark Agouti and Lewis rats, FI  = 1.4% and 4.1%, respectively) confirm the low chiral inversion of the enantiomers of flurbiprofen in the rat, as observed by other authors in the Sprague-Dawley strain (<5%). From the present results, we conclude that for the study of flurbiprofen enantiomers, the rat is more suitable than the mouse as a model for the human in which (R)-inversion to (S)-inversion is negligible.

A minimal impact of long-term S-flurbiprofen plaster application on kidney function in osteoarthritis patients.

BACKGROUND: The number of kidney injury due to nonsteroidal anti-inflammatory drugs (NSAIDs) is the largest among drug-induced kidney diseases. Newly developed NSAID plaster containing S-flurbiprofen (SFP) shows innovative percutaneous absorption. However, systemic exposure to SFP following the repeated application of 80 mg/day was estimated as comparable to that of oral 120 mg/day flurbiprofen and prolonged use of topical NSAIDs is common in clinical practice. Thus, we report the safety focusing on the kidney function after long-term application of SFP plaster (SFPP). METHODS: A total of 201 osteoarthritis patients (mean age; 66.3, 151 females, mean estimated glomerular filtration rate; 74.6 mL/min/1.73 mm2) were applied 40 or 80 mg SFPP for 52 weeks, and kidney function was examined by blood urea nitrogen (BUN), serum creatinine (SCr), eGFR, and urinalysis. RESULTS: 161 (80.1%) patients completed 52-week application. In both groups of 40 and 80 mg, small but statistically significant increases were observed in BUN (mean 1.91 and 1.89 mg/dL, p < 0.05) and SCr (mean 0.019 and 0.022 mg/dL, p < 0.05). Although abnormal changes in laboratory test for renal function were observed in seven patients, all the changes were small and subclinical. Acute kidney injury was observed in two patients. Meanwhile, the investigators denied the relevance of SFPP according to the clinical course. CONCLUSION: Toward the end of 52-week application, a statistically significant increase in SCr was observed in both 40 and 80 mg, but increment was small and subclinical. Attention should be paid to kidney function when applying SFPP to patients with multiple risk factors.

Efficacy of S-flurbiprofen plaster in knee osteoarthritis treatment: Results from a phase III, randomized, active-controlled, adequate, and well-controlled trial.

OBJECTIVES: S-flurbiprofen plaster (SFPP) is a novel non-steroidal anti-inflammatory drug (NSAID) patch, intended for topical treatment for musculoskeletal diseases. This trial was conducted to examine the effectiveness of SFPP using active comparator, flurbiprofen (FP) patch, on knee osteoarthritis (OA) symptoms. METHODS: This was a phase III, multi-center, randomized, adequate, and well-controlled trial, both investigators and patients were blinded to the assigned treatment. Enrolled 633 knee OA patients were treated with either SFPP or FP patch for two weeks. The primary endpoint was improvement in knee pain on rising from the chair as assessed by visual analogue scale (rVAS). Safety was evaluated through adverse events (AEs). RESULTS: The change in rVAS was 40.9 mm in SFPP group and 30.6 mm in FP patch group (p < 0.001). The incidence of drug-related AEs at the application site was 9.5% (32 AEs, 29 mild and 3 moderate) in SFPP and 1.6% in FP patch (p < 0.001). Withdrawals due to AE were five in SFPP and one in FP patch. CONCLUSIONS: The superiority of SFPP in efficacy was demonstrated. Most of AEs were mild and few AEs led to treatment discontinuation. Therefore, SFPP provides an additional option for knee OA therapy.

Topical Anti-Inflammatory and Analgesic Effects of Multiple Applications of S(+)-Flurbiprofen Plaster (SFPP) in a Rat Adjuvant-Induced Arthritis Model.

Preclinical Research The aim of this study was to evaluate the efficacy of multiple applications of S(+)-flurbiprofen plaster (SFPP), a novel Nonsteroidal anti-inflammatory drug (NSAID) patch, for the alleviation of inflammatory pain and edema in rat adjuvant-induced arthritis (AIA) model as compared to other NSAID patches. The AIA model was induced by the injection of Mycobacterium butyricum and rats were treated with a patch (1.0 cm × 0.88 cm) containing each NSAID (SFP, ketoprofen, loxoprofen, diclofenac, felbinac, flurbiprofen, or indomethacin) applied to the paw for 6 h per day for 5 days. The pain threshold was evaluated using a flexion test of the ankle joint, and the inflamed paw edema was evaluated using a plethysmometer. cyclooxygenase (COX)-1 and COX-2 inhibition was evaluated using human recombinant proteins. Multiple applications of SFPP exerted a significant analgesic effect from the first day of application as compared to the other NSAID patches. In terms of paw edema, SFPP decreased edema from the second day after application, Multiple applications of SFPP were superior to those of other NSAID patches, in terms of the analgesic effect with multiple applications. These results suggest that SFPP may be a beneficial patch for providing analgesic and anti-inflammatory effects clinically. Drug Dev Res 77 : 206-211, 2016. © 2016 The Authors Drug Development Research Published by Wiley Periodicals, Inc.

Analgesic Effect of the Newly Developed S(+)-Flurbiprofen Plaster on Inflammatory Pain in a Rat Adjuvant-Induced Arthritis Model.

Preclinical Research This article describes the properties of a novel topical NSAID (Nonsteroidal anti-inflammatory drug) patch, SFPP (S(+)-flurbiprofen plaster), containing the potent cyclooxygenase (COX) inhibitor, S(+)-flurbiprofen (SFP). The present studies were conducted to confirm human COX inhibition and absorption of SFP and to evaluate the analgesic efficacy of SFPP in a rat adjuvant-induced arthritis (AIA) model. COX inhibition by SFP, ketoprofen and loxoprofen was evaluated using human recombinant COX proteins. Absorption of SFPP, ketoprofen and loxoprofen from patches through rat skin was assessed 24 h after application. The AIA model was induced by injecting Mycobacterium tuberculosis followed 20 days later by the evaluation of the prostaglandin PGE2 content of the inflamed paw and the pain threshold. SFP exhibited more potent inhibitory activity against COX-1 (IC50 = 8.97 nM) and COX-2 (IC50 = 2.94 nM) than the other NSAIDs evaluated. Absorption of SFP was 92.9%, greater than that of ketoprofen and loxoprofen from their respective patches. Application of SFPP decreased PGE2 content from 15 min to 6 h and reduced paw hyperalgesia compared with the control, ketoprofen and loxoprofen patches. SFPP showed analgesic efficacy, and was superior to the ketoprofen and loxoprofen patches, which could be through the potent COX inhibitory activity of SFP and greater skin absorption. The results suggested SFPP can be expected to exert analgesic effect clinically.

Plasma pharmacokinetics and synovial concentrations of S-flurbiprofen plaster in humans.

PURPOSE: The purpose of this study is to investigate the pharmacokinetics and deep tissue penetration capability of the newly developed S-flurbiprofen plaster (SFPP) in humans. METHODS: Study 1: SFPP tape-type patch (2-60 mg) was applied to the lower back for 24 h in healthy adult volunteers. S-flurbiprofen (SFP) plasma concentration was measured over time to examine SFP pharmacokinetics. Study 2: SFPP (20 mg) was applied for 12 h to the affected knee of osteoarthritis (OA) patients who were scheduled for total knee arthroplasty. Deep tissues (synovial tissue and synovial fluid) were collected during surgery to compare SFP concentrations after application of SFPP or a commercially available flurbiprofen (FP) gel-type patch. RESULTS: Study 1: The plasma concentration of SFP was sustained during 24-h topical application of the SFPP, showing a high percutaneous absorption ratio of 51.4-72.2 %. Cmax and AUC0-∞ were dose-proportional. Study 2: After application of the SFPP for 12 h, SFP concentrations in the synovial tissue and synovial fluid were 14.8-fold (p = 0.002) and 32.7-fold (p < 0.001) higher, respectively, than those achieved by the FP patch. CONCLUSIONS: Sustained plasma concentration of SFP and high percutaneous absorption ratio was observed after 24-h topical application of the SFPP. Compared to the FP patch, the SFPP showed superior percutaneous absorption and greater tissue penetration of SFP into the synovial tissue. Greater tissue penetration of the SFPP seemed to be primarily due to its formulation. Thus, SFPP is expected to show higher efficacy for the treatment of knee OA.