Screening of poly-beta amino ester coated emulsion of ketorolac for cartilage delivery.

Osteoarthritis (OA) is a prevalent chronic health condition necessitating effective treatment strategies. Globally, there were 86 million people with incident knee osteoarthritis in 2020. Pain management remains the primary approach to OA as the nature of cartilage poses challenges for drug delivery. An emulsion-based delivery system, using a class of positively charged and hydrolysable polymers (poly-beta-amino-esters) to coat oil droplets containing drugs, has been shown to enhance and prolong drug localization in ex vivo cartilage models. As the properties of the polymers used in this technology strongly depend on the monomers used in the synthesis, this study presents the screening of a wide range of PBAEs as droplet coating agents and using ketorolac as a model of nonsteroidal anti-inflammatory drugs. The emulsions prepared with this PBAE library were characterized, and drug localisation and retention were evaluated in both native and glycosaminoglycan (GAG) depleted cartilage ex vivo models. Optimal candidates were identified and tested in an ex vivo model showing the ability to protect chondrocyte cell viability and increase both GAG and collagen contents in cartilage exposed to cytokine (IL-1α) simulating acute cartilage damage. This work demonstrates the potential of PBAE coated emulsion as a delivery system for effective drug delivery in OA treatment.

Molecular modelling approaches predicted 1,2,3-triazolyl ester of ketorolac (15K) to be a novel allosteric modulator of the oncogenic kinase PAK1.

P21-activated kinases (PAKs) are serine/threonine protein kinase which have six different isoforms (PAK1-6). Of those, PAK1 is overexpressed in many cancers and considered to be a major chemotherapeutic target. Most of the developed PAK1 inhibitor drugs work as pan-PAK inhibitors and show undesirable toxicity due to having untargeted kinase inhibition activities. Selective PAK1 inhibitors are therefore highly desired and oncogenic drug hunters are trying to develop allosteric PAK1 inhibitors. We previously synthesized 1,2,3-triazolyl ester of ketorolac (15K) through click chemistry technique, which exhibits significant anti-cancer effects via inhibiting PAK1. Based on the selective anticancer effects of 15K against PAK1-dependent cancer cells, we hypothesize that it may act as an allosteric PAK1 inhibitor. In this study, computational analysis was done with 15K to explore its quantum chemical and thermodynamic properties, molecular interactions and binding stability with PAK1, physicochemical properties, ADMET, bioactivities, and druglikeness features. Molecular docking analysis demonstrates 15K as a potent allosteric ligand that strongly binds to a novel allosteric site of PAK1 (binding energy ranges - 8.6 to - 9.2 kcal/mol) and does not target other PAK isoforms; even 15K shows better interactions than another synthesized PAK1 inhibitor. Molecular dynamics simulation clearly supports the stable binding properties of 15K with PAK1 crystal. Density functional theory-based calculations reveal that it can be an active drug with high softness and moderate polarity, and ADMET predictions categorize it as a non-toxic drug as evidenced by in vitro studies with brine shrimp and fibroblast cells. Structure-activity relationship clarifies the role of ester bond and triazol moiety of 15K in establishing novel allosteric interactions. Our results summarize that 15K selectively inhibits PAK1 as an allosteric inhibitor and in turn shows anticancer effects without toxicity.

Development of Composition and Technologies of Dental Film with Ketorolac Trometamine.

The report presents the results of the development of dental films with ketorolac trometamine based on the natural biodegradable polymers from the groups of sodium alginates and xanthan gums in combination with lightly crosslinked acrylic polymer carbopol. Physicochemical properties, such as moisture, mucoadhesion, thickness, tensile strength, disintegration in phosphate buffer were determined in obtained samples of this dosage form. A comparison of physicochemical properties of experimental samples and commercial model of dental film has allowed establishing the perspective composition of complex matrix of films with ketorolac trometamine for use in dentistry.

Long-term stability of an infusion containing paracetamol, alizapride, ketorolac and tramadol in glass bottles at 5±3°C.

Background and objective: Infusion containing paracetamol, alizapride, ketorolac and tramadol is used after a general anaesthesia in order to limit pain, fever and nausea. Currently, these infusions are prepared according to demand in the anaesthesia unit, but the preparation in advance could improve quality of preparation and time management. The aim of this study was to investigate the long-term stability of this infusion in glass bottles at 5°C ± 3 °C. Method: Five bottles of infusion were stored at 5°C ± 3 °C for 60 days. A visual and microscope inspection were performed periodically to observe any particle appearance or colour change. pH and absorbance at three wavelengths were measured. The concentrations were measured by ultra-high performance liquid chromatography - diode array detection. Results: Multiple verifications were performed during the first 35 days and no crystal, impurity or colour change were observed. At the next time point (42nd day), crystals were visible to the naked eye. pH and absorbance at 350 nm and 550 nm were stable. A slight increase in the absorbance at 410 nm was observed during the study, suggesting that a degradation product could be formed and absorb at this wavelength. The infusion was considered chemically stable while the lower one-sided prediction limit at 95% remains superior to 90% of the initial concentration. Concentration measurements demonstrated that ketorolac and alizapride remained stable in the infusion for 35 days. The stability of tramadol was 28 days. However, degradation of paracetamol was much faster given that concentration has fallen below 90% of the initial concentration after 7 days. Conclusion: Infusion of paracetamol, alizapride, ketorolac and tramadol remains stable for 7 days in glass bottles at 5°C ± 3 °C and could be prepared in advance with these storage conditions.

Design of the ocular coil, a new device for non-invasive drug delivery.

Eye drops and ointments are the most prescribed methods for ocular drug delivery. However, due to low drug bioavailability, rapid drug elimination, and low patient compliance there is a need for improved ophthalmic drug delivery systems. This study provides insights into the design of a new drug delivery device that consists of an ocular coil filled with ketorolac loaded PMMA microspheres. Nine different ocular coils were created, ranging in wire diameter and coiled outer diameter. Based on its microsphere holding capacity and flexibility, one type of ocular coil was selected and used for further experiments. No escape of microspheres was observed after bending the ocular coil at curvature which reflect the in vivo situation in human upon positioning in the lower conjunctival sac. Shape behavior and tissue contact were investigated by computed tomography imaging after inserting the ocular coil in the lower conjunctival fornix of a human cadaver. Thanks to its high flexibility, the ocular coil bends along the circumference of the eye. Because of its location deep in the fornix, it appears unlikely that in vivo, the ocular coil will interfere with eye movements. In vitro drug release experiments demonstrate the potential of the ocular coil as sustained drug delivery device for the eye. We developed PMMA microspheres with a 26.5 ± 0.3 wt% ketorolac encapsulation efficiency. After 28 days, 69.9% ± 5.6% of the loaded ketorolac was released from the ocular coil when tested in an in vitro lacrimal system. In the first three days high released dose (48.7% ± 5.4%) was observed, followed by a more gradually release of ketorolac. Hence, the ocular coil seems a promising carrier for ophthalmic drugs delivery in the early postoperative time period.

Synthesis and highly potent anti-inflammatory activity of licofelone- and ketorolac-based 1-arylpyrrolizin-3-ones.

Since NSAIDs are commonly used anti-inflammatory agents that produce adverse effects, there have been ongoing efforts to develop more effective and less toxic compounds. Based on the structure of the anti-inflammatory pyrrolizines licofelone and ketorolac, a series of 1-arylpyrrolizin-3-ones was synthesized. Also prepared was a series of substituted pyrroles, mimicking similar known anti-inflammatory agents. The anti-inflammatory activity of the test compounds was determined with a phorbol ester (TPA)-induced murine ear edema protocol. For the most active derivatives, 19b-c/20b-c, the anti-inflammatory effect was the same as that of the reference compound (indomethacin) and was dose-dependent. These compounds have an aryl ring at the C-1 position and a methoxycarbonyl group at the C-2 position of the pyrrolizine framework, which represent plausible pharmacophore groups with anti-inflammatory activity. The anti-inflammatory activity of 1-substituted analogs containing a five- or six-membered heterocycles was lower but still good, while that of the pyrroles was only moderate. Although the docking studies suggests that the effect of analogs 19a-c/20a-c is associated with the inhibition of cyclooxygenase-2, experimental assays did not corroborate this idea. Indeed, a significant inhibition of NO was found experimentally as a plausible mechanism of action.

Capping of silver nanoparticles by anti-inflammatory ligands: Antibacterial activity and superoxide anion generation.

Silver nanoparticles (AgNPs) have been widely recognized as antibacterial agents. However, its stability and activity over time have been poorly studied. In this work, the properties and characteristics of differently stabilized AgNPs were evaluated during a span of time. The surface capping agents were diclofenac (d), and ketorolac (k), which currently are used as anti-inflammatory in human medicine. On evaluating the size variation over time, it was observed that the AgNPs-k are the most stable, unlike the non-capped nanoparticles agglomerate and precipitate. UV-Vis spectroscopy analysis showed that the absorbance during time decreases for the three types of nanoparticles, but the decrease is less marked for the two types of anti-inflammatory-capped AgNPs. The rapid loss of the optical prop- erties of bare AgNPs, is mainly due to oxidation, agglomeration, and precipitation of this nanoparticles. The potential cytotoxicity of the AgNPs, evaluated through the formation of the superoxide anion using XXT, showed that both, AgNPs-k and AgNPs-d, generate the radical anion when the samples are irradiated with UV light at 365 nm. This effect appears associated with the capping agents, since the bare nanoparticles did not promote the formation of the superoxide anion. The antibacterial activity of the AgNPs throughout time, against two microorganisms (Escherichia coli and Staphylococcus aureus), was also evaluated. The results showed that capping agents played a decisive role in the antibacterial ability of AgNPs and also in enhancing the antibacterial activity over time.

Optimization of structures, biochemical properties of ketorolac and its degradation products based on computational studies.

BACKGROUND: Ketorolac (KTR) is used as an analgesic drug with an efficacy close to that of the opioid family. It is mainly used for the short term treatment of post-operative pain. It can inhibit the prostaglandin synthesis by blocking cyclooxygenase (COX). METHODS: In this investigation, the inherent stability and biochemical interaction of Ketorolac (KTR) and its degradation products have been studiedon the basis of quantum mechanical approaches. Density functional theory (DFT) with B3LYP/ 6-31G (d) has been employed to optimize the structures. Thermodynamic properties, frontier molecular orbital features, dipole moment, electrostatic potential, equilibrium geometry, vibrational frequencies and atomic partial charges of these optimized structureswere investigated. Molecular docking has been performed against prostaglandin H2 (PGH2) synthase protein 5F19 to search the binding affinity and mode(s). ADMET prediction has performed to evaluate the absorption, metabolism and carcinogenic properties. RESULTS: The equilibrium geometry calculations support the optimized structures. Thermodynamic results disclosed the thermal stability of all structures. From molecular orbital data, all the degradents are chemically more reactive than parent drug (except K3). However, the substitution of carboxymethyl radicalin K4 improved the physicochemical properties and binding affinity. ADMET calculations predict the improved pharmacokinetic and non-carcinogenic properties of all degradents. CONCLUSION: Based on physicochemical, molecular docking, and ADMET calculation, this study can be helpful to understand the biochemical activities of Ketorolac and its degradents and to design a potent analgesic drug.

Dual drug delivery from intraocular lens material for prophylaxis of endophthalmitis in cataract surgery.

Cataract is highly prevalent among old population worldwide and replacement of the opacified crystalline lens by an intraocular lens (IOL) is the safest and the most effective treatment. Although not very frequently (0.02-0.33% of the cases), the patients who undergo cataract surgery may develop endophthalmitis, which is a serious problem eventually leading to blindness. To avoid this complication, the postoperative instillation of antibiotics and anti-inflammatories is almost universally used in clinical practice. The aim of this work was to study the possibility of loading an IOL material with an antibiotic and an anti-inflammatory, which could be simultaneously released and successfully substitute the frequent instillation of topical drops for the prevention of endophthalmitis. The IOL material commercially available under the name of CI26Y (Contamac Products) was chosen and two pairs of drugs consisting of one antibiotic and one anti-inflammatory were tested: moxifloxacin + ketorolac and moxifloxacin + diclofenac. The drug loading was done by soaking under optimized conditions. Simultaneous drug loading improved the release profiles, especially in the case of moxifloxacin + ketorolac. The effect of sterilization by steam heat (carried out on the first day of loading) and by gamma-radiation upon the release profiles was negligible. The optical and mechanical properties of the sterilized, double-loaded IOL materials were kept at adequate levels. Application of a mathematical model to predict the in vivo released concentrations suggested that the most efficient system complied with the therapeutic needs: the lens loaded with moxifloxacin + ketorolac was effective against S. aureus and S. epidermidis up to 15 days, and the amount of released ketorolac remained active against inflammation for a minimum of 16 days.

Sublingual spray drug delivery of ketorolac-loaded chitosan nanoparticles.

INTRODUCTION: The aim of this study was to investigate ketorolac (KT) systemic absolute bioavailability after sublingual (SL) administration in vivo to conscious rabbits. Furthermore, the study investigated the potential use of chitosan nanoparticles as a delivery system to enhance the systemic bioavailability of KT following SL administration. METHODS: Ketorolac-loaded chitosan nanoparticles were prepared through ionotropic gelation of chitosan with tripolyphosphate anions. The KT-nanoparticles were administered SL as a spray to rabbits and KT plasma concentration at predetermined time points was compared to SL spray administration of KT in solution. The concentrations of KT in plasma were analyzed by ultra-performance liquid chromatography mass spectroscopy (UPLC/MS). RESULTS: KT-loaded chitosan nanoparticles significantly (p < .05) enhanced systemic absorption with 97% absolute bioavailability as compared to 70% after SL administration of KT solution. CONCLUSIONS: The results of the present study suggest that SL absorption of KT illustrated flip-flop kinetics with prolonged persistence in the body compared to intravenous administration. Formulation of KT as chitosan nanoparticles has increased its systemic bioavailability after SL spray administration. The new delivery system could be an attractive approach for the delivery of KT.

Improving sustained drug delivery from ophthalmic lens materials through the control of temperature and time of loading.

Although the possibility of using drug-loaded ophthalmic lens to promote sustained drug release has been thoroughly pursued, there are still problems to be solved associated to the different alternatives. In this work, we went back to the traditional method of drug loading by soaking in the drug solution and tried to optimize the release profiles by changing the temperature and the time of loading. Two materials commercially available under the names of CI26Y and Definitive 50 were chosen. CI26Y is used for intraocular lenses (IOLs) and Definitive 50 for soft contact lenses (SCLs). Three drugs were tested: an antibiotic, moxifloxacin, and two anti-inflammatories, diclofenac and ketorolac. Sustained drug release from CI26Y disks for, at least 15 days, was obtained for moxifloxacin and diclofenac increasing the loading temperature up to 60 °C or extending the loading time till two months. The sustained release of ketorolac was limited to about 8 days. In contrast, drug release from Definitive 50 disks could not be improved by changing the loading conditions. An attempt to interpret the impact of the loading conditions on the drug release behavior was done using solid-state NMR and differential scanning calorimetry. These studies suggested the establishment of reversible, endothermic interactions between CI26Y and the drugs, moxifloxacin and diclofenac. The loading temperature had a slight effect on the mechanical and optical properties of drug loaded CI26Y samples, which still kept adequate properties to be used as IOL materials. The in vivo efficacy of CI26Y samples, drug loaded at 60 °C for two weeks, was predicted using a simplified mathematical model to estimate the drug concentration in the aqueous humor. The estimated concentrations were found to comply with the therapeutic needs, at least, for moxifloxacin and diclofenac.

Stability indicating HPLC-DAD method for analysis of Ketorolac binary and ternary mixtures in eye drops: Quantitative analysis in rabbit aqueous humor.

Ketorolac tromethamine (KTC) with phenylephrine hydrochloride (PHE) binary mixture (mixture 1) and their ternary mixture with chlorpheniramine maleate (CPM) (mixture 2) were analyzed using a validated HPLC-DAD method. The developed method was suitable for the in vitro as well as quantitative analysis of the targeted mixtures in rabbit aqueous humor. The analysis in dosage form (eye drops) was a stability indicating one at which drugs were separated from possible degradation products arising from different stress conditions (in vitro analysis). For analysis in aqueous humor, Guaifenesin (GUF) was used as internal standard and the method was validated according to FDA regulation for analysis in biological fluids. Agilent 5 HC-C18(2) 150×4.6mm was used as stationary phase with a gradient eluting solvent of 20mM phosphate buffer pH 4.6 containing 0.2% triethylamine and acetonitrile. The drugs were resolved with retention times of 2.41, 5.26, 7.92 and 9.64min for PHE, GUF, KTC and CPM, respectively. The method was sensitive and selective to analyze simultaneously the three drugs in presence of possible forced degradation products and dosage form excipients (in vitro analysis) and also with the internal standard, in presence of aqueous humor interferences (analysis in biological fluid), at a single wavelength (261nm). No extraction procedure was required for analysis in aqueous humor. The simplicity of the method emphasizes its capability to analyze the drugs in vivo (in rabbit aqueous humor) and in vitro (in pharmaceutical formulations).

Lidocaine/ketorolac-loaded biodegradable nanofibrous anti-adhesive membranes that offer sustained pain relief for surgical wounds.

The aim of this study was to develop and evaluate the effectiveness of biodegradable nanofibrous lidocaine/ketorolac-loaded anti-adhesion membranes to sustainably release analgesics on abdominal surgical wounds. The analgesic-eluting membranes with two polymer-to-drug ratios (6:1 and 4:1) were produced via an electrospinning technique. A high-performance liquid chromatography (HPLC) assay was employed to characterize the in vivo and in vitro release behaviors of the pharmaceuticals from the membranes. It was found that all biodegradable anti-adhesion nanofibers released effective concentrations of lidocaine and ketorolac for over 20 days post surgery. In addition, a transverse laparotomy was setup in a rat model for an in vivo assessment of activity of postoperative recovery. No tissue adhesion was observed at 2 weeks post surgery, demonstrating the potential anti-adhesion capability of the drug-eluting nanofibrous membrane. The postoperative activities were recorded for two groups of rats as follows: rats that did not have any membrane implanted (group A) and rats that had the analgesic-eluting membrane implanted (group B). Rats in group B exhibited faster recovery times than those in group A with regard to postoperative activities, confirming the pain relief effectiveness of the lidocaine- and ketorolac-loaded nanofibrous membranes. The experimental results suggested that the anti-adhesion nanofibrous membranes with sustainable elution of lidocaine and ketorolac are adequately effective and durable for the purposes of postoperative pain relief in rats.

Using Ligand-Induced Protein Chemical Shift Perturbations To Determine Protein-Ligand Structures.

Protein chemical shift perturbations (CSPs), upon ligand binding, can be used to refine the structure of a protein-ligand complex by comparing experimental CSPs with calculated CSPs for any given set of structural coordinates. Herein, we describe a fast and accurate methodology that opens up new opportunities for improving the quality of protein-ligand complexes using nuclear magnetic resonance (NMR)-based approaches by focusing on the effect of the ligand on the protein. The new computational approach, 1H empirical chemical shift perturbation (HECSP), has been developed to rapidly calculate ligand binding-induced 1H CSPs in a protein. Given the dearth of experimental information by which a model could be derived, we employed high-quality density functional theory (DFT) computations using the automated fragmentation quantum mechanics/molecular mechanics approach to derive a database of ligand-induced CSPs on a series of protein-ligand complexes. Overall, the empirical HECSP model yielded correlation coefficients between its predicted and DFT-computed values of 0.897 (1HA), 0.971 (1HN), and 0.945 (side chain 1H) with root-mean-square errors of 0.151 (1HA), 0.199 (1HN), and 0.257 ppm (side chain 1H), respectively. Using the HECSP model, we developed a scoring function (NMRScore_P). We describe two applications of NMRScore_P on two complex systems and demonstrate that the method can distinguish native ligand poses from decoys and refine protein-ligand complex structures. We provide further refined models for both complexes, which satisfy the observed 1H CSPs in experiments. In conclusion, HECSP coupled with NMRScore_P provides an accurate and rapid platform by which protein-ligand complexes can be refined using NMR-derived information.

Non-steroidal Anti-inflammatory Drugs Are Caspase Inhibitors.

Non-steroidal anti-inflammatory drugs (NSAIDs) are among the most commonly used drugs in the world. While the role of NSAIDs as cyclooxygenase (COX) inhibitors is well established, other targets may contribute to anti-inflammation. Here we report caspases as a new pharmacological target for NSAID family drugs such as ibuprofen, naproxen, and ketorolac at physiologic concentrations both in vitro and in vivo. We characterize caspase activity in both in vitro and in cell culture, and combine computational modeling and biophysical analysis to determine the mechanism of action. We observe that inhibition of caspase catalysis reduces cell death and the generation of pro-inflammatory cytokines. Further, NSAID inhibition of caspases is COX independent, representing a new anti-inflammatory mechanism. This finding expands upon existing NSAID anti-inflammatory behaviors, with implications for patient safety and next-generation drug design.

1,2,3-Triazolyl ester of Ketorolac: A "Click Chemistry"-based highly potent PAK1-blocking cancer-killer.

An old anti-inflammatory/analgesic drug called Toradol is a racemic form of Ketorolac (50% R-form and 50% S-form) that blocks the oncogenic RAC-PAK1-COX-2 (cyclooxygenase-2) signaling, through the direct inhibition of RAC by the R-form and of COX-2 by the S-form, eventually down-regulating the production of prostaglandins. However, due to its COOH moiety which is clearly repulsive to negatively-charged phospholipid-based plasma membrane, its cell-permeability is rather poor (the IC50 against the growth of human cancer cells such as A549 is around 13 µM). In an attempt to boost its anti-cancer activity, hopefully by increasing its cell-permeability through abolishing the negative charge, yet keeping its water-solubility, here we synthesized a 1,2,3-triazolyl ester of Toradol through "Click Chemistry". The resultant water-soluble "azo" derivative called "15K" was found to be over 500 times more potent than Toradol with the IC50 around 24 nM against the PAK1-dependent growth of A549 cancer cells, inactivating PAK1 in cell culture with the apparent IC50 around 65 nM, and inhibiting COX-2 in vitro with the IC50 around 6 nM. Furthermore, the Click Chemistry boosts the anti-cancer activity of Ketorolac by 5000 times against the PAK1-independent growth of B16F10 melanoma cells. Using a multi-drug-resistant (MDR) cancer cell line (EMT6), we found that the esterization of Ketorolac boosts its cell-permeability by at least 10 folds. Thus, the Click Chemistry dramatically boosts the anti-cancer activity of Ketorolac, at least in three ways: increasing its cell-permeability, the anti-PAK1 activity of R-form and anti-COX-2 activity of S-form. The resultant "15K" is so far among the most potent PAK1-blockers, and therefore would be potentially useful for the therapy of many different PAK1-dependent diseases/disorders such as cancers.

Double-blind, randomized, double-dummy clinical trial comparing the efficacy of ketorolac trometamol and naproxen for acute low back pain.

BACKGROUND: Nonsteroidal anti-inflammatory drugs (NSAIDs) are the most common type of medication used in the treatment of acute pain. Ketorolac trometamol (KT) is a nonnarcotic, peripherally acting nonsteroidal anti-inflammatory drug with analgesic effects comparable to certain opioids. OBJECTIVE: The aim of this study was to compare the efficacy of KT and naproxen (NA) in the treatment of acute low back pain (LBP) of moderate-to-severe intensity. PATIENTS AND METHODS: In this 10-day, Phase III, randomized, double-blind, double-dummy, noninferiority trial, participants with acute LBP of moderate-to-severe intensity as determined through a visual analog scale (VAS) were randomly assigned in a 1:1 ratio to receive sublingual KT 10 mg three times daily or oral NA 250 mg three times daily. From the second to the fifth day of treatment, if patient had VAS >40 mm, increased dosage to four times per day was allowed. The primary end point was the reduction in LBP as measured by VAS. We also performed a post hoc superiority analysis. RESULTS: KT was not inferior to NA for the reduction in LBP over 5 days of use as measured by VAS scores (P=0.608 for equality of variance; P=0.321 for equality of means) and by the Roland-Morris Disability Questionnaire (P=0.180 for equality of variance test; P=0.446 for equality of means) using 95% confidence intervals. The percentage of participants with improved pain relief 60 minutes after receiving the first dose was higher in the KT group (24.2%) than in the NA group (6.5%; P=0.049). The most common adverse effects were heartburn, nausea, and vomiting. CONCLUSION: KT is not inferior in efficacy and delivers faster pain relief than NA.

Novel Activities of Select NSAID R-Enantiomers against Rac1 and Cdc42 GTPases.

Rho family GTPases (including Rac, Rho and Cdc42) collectively control cell proliferation, adhesion and migration and are of interest as functional therapeutic targets in numerous epithelial cancers. Based on high throughput screening of the Prestwick Chemical Library® and cheminformatics we identified the R-enantiomers of two approved drugs (naproxen and ketorolac) as inhibitors of Rac1 and Cdc42. The corresponding S-enantiomers are considered the active component in racemic drug formulations, acting as non-steroidal anti-inflammatory drugs (NSAIDs) with selective activity against cyclooxygenases. Here, we show that the S-enantiomers of naproxen and ketorolac are inactive against the GTPases. Additionally, more than twenty other NSAIDs lacked inhibitory action against the GTPases, establishing the selectivity of the two identified NSAIDs. R-naproxen was first identified as a lead compound and tested in parallel with its S-enantiomer and the non-chiral 6-methoxy-naphthalene acetic acid (active metabolite of nabumetone, another NSAID) as a structural series. Cheminformatics-based substructure analyses-using the rotationally constrained carboxylate in R-naproxen-led to identification of racemic [R/S] ketorolac as a suitable FDA-approved candidate. Cell based measurement of GTPase activity (in animal and human cell lines) demonstrated that the R-enantiomers specifically inhibit epidermal growth factor stimulated Rac1 and Cdc42 activation. The GTPase inhibitory effects of the R-enantiomers in cells largely mimic those of established Rac1 (NSC23766) and Cdc42 (CID2950007/ML141) specific inhibitors. Docking predicts that rotational constraints position the carboxylate moieties of the R-enantiomers to preferentially coordinate the magnesium ion, thereby destabilizing nucleotide binding to Rac1 and Cdc42. The S-enantiomers can be docked but are less favorably positioned in proximity to the magnesium. R-naproxen and R-ketorolac have potential for rapid translation and efficacy in the treatment of several epithelial cancer types on account of established human toxicity profiles and novel activities against Rho-family GTPases.

Optimization of combinational intranasal drug delivery system for the management of migraine by using statistical design.

Migraine is a chronic disorder characterized by significant headache and various associated symptoms which worsen with exertion. Zolmitriptan approved for use in the acute treatment of migraine and related vascular headaches but are limited by high pain recurrence due to rapid drug elimination. Combinationalformulationof triptans and a nonsteroidal anti-inflammatory drug may provide a quicker and longer duration of relief from the subsequent pain during the attack. In this study, we formulate a Zolmitriptan (ZT) & ketorolac tromethamine (KT) loaded thermo reversible in-situ mucoadhesive intranasal gel (TMISG) formulation which gels at the nasal mucosal temperature and contains a bioadhesive polymer (Xyloglucan) that lengthens the residence time will enhance the bioavailability of the combinational drugs. This study uses Box-Behnken design for the first time to develop, optimize the TMISG and assess factors affecting the critical quality attributes. Histopathological study of the nasal mucosa suggested that the formulation was safe for nasal administration. The statistical difference in absolute bioavailability between oral and intranasal route suggested that intranasal route had almost 21% increases in bioavailability for ZT and for KT there was 16% increase over oral formulations. Optimized formulation would help mitigate migraine associated symptoms much better over the currently available formulations.

Novel stereoselective high-performance liquid chromatographic method for simultaneous determination of guaifenesin and ketorolac enantiomers in human plasma.

A novel method was developed for the simultaneous determination of guaifenesin (GUA) and ketorolac tromethamine (KET) enantiomers in plasma samples. Since GUA probably increases the absorption of coadministered drugs (e.g., KET), it would be extremely important to monitor KET plasma levels for the purpose of dose adjustment with a subsequent decrease in the side effects. Enantiomeric resolution was achieved on a polysaccharide-based chiral stationary phase, amylose-2, as a chiral selector under the normal phase (NP) mode and using ornidazole (ORN) as internal standard. This innovative method has the advantage of the ease and reliability of sample preparation for plasma samples. Sample clean-up was based on simply using methanol for protein precipitation followed by direct extraction of drug residues using ethanol. Both GUA and KET enantiomers were separated using an isocratic mobile phase composed of hexane/isopropanol/trifluoroacetic acid, 85:15:0.05 v/v/v. Peak area ratios were linear over the range 0.05-20 µg/mL for the four enantiomers S (+) GUA, R (-) GUA, R (+) KET, and S (-) KET. The method was fully validated according to the International Conference on Harmonization (ICH) guidelines in terms of system suitability, specificity, accuracy, precision, robustness, and solution stability. Finally, this procedure was innovative to apply the rationale of developing a chiral high-performance liquid chromatography (HPLC) procedure for the simultaneous quantitative analysis of drug isomers in clinical samples.