The putative proton-coupled organic cation antiporter is involved in uptake of triptans into human brain capillary endothelial cells.

BACKGROUND: Triptans are anti-migraine drugs with a potential central site of action. However, it is not known to what extent triptans cross the blood-brain barrier (BBB). The aim of this study was therefore to determine if triptans pass the brain capillary endothelium and investigate the possible underlying mechanisms with focus on the involvement of the putative proton-coupled organic cation (H+/OC) antiporter. Additionally, we evaluated whether triptans interacted with the efflux transporter, P-glycoprotein (P-gp). METHODS: We investigated the cellular uptake characteristics of the prototypical H+/OC antiporter substrates, pyrilamine and oxycodone, and seven different triptans in the human brain microvascular endothelial cell line, hCMEC/D3. Triptan interactions with P-gp were studied using the IPEC-J2 MDR1 cell line. Lastly, in vivo neuropharmacokinetic assessment of the unbound brain-to-plasma disposition of eletriptan was conducted in wild type and mdr1a/1b knockout mice. RESULTS: We demonstrated that most triptans were able to inhibit uptake of the H+/OC antiporter substrate, pyrilamine, with eletriptan emerging as the strongest inhibitor. Eletriptan, almotriptan, and sumatriptan exhibited a pH-dependent uptake into hCMEC/D3 cells. Eletriptan demonstrated saturable uptake kinetics with an apparent Km of 89 ± 38 µM and a Jmax of 2.2 ± 0.7 nmol·min-1·mg protein-1 (n = 3). Bidirectional transport experiments across IPEC-J2 MDR1 monolayers showed that eletriptan is transported by P-gp, thus indicating that eletriptan is both a substrate of the H+/OC antiporter and P-gp. This was further confirmed in vivo, where the unbound brain-to-unbound plasma concentration ratio (Kp,uu) was 0.04 in wild type mice while the ratio rose to 1.32 in mdr1a/1b knockout mice. CONCLUSIONS: We have demonstrated that the triptan family of compounds possesses affinity for the H+/OC antiporter proposing that the putative H+/OC antiporter plays a role in the BBB transport of triptans, particularly eletriptan. Our in vivo studies indicate that eletriptan is subjected to simultaneous brain uptake and efflux, possibly facilitated by the putative H+/OC antiporter and P-gp, respectively. Our findings offer novel insights into the potential central site of action involved in migraine treatment with triptans and highlight the significance of potential transporter related drug-drug interactions.

[Comparative clinical study of pharmacokinetics and bioequivalence of Relonova and Maxalt]. / Sravnitel'noe klinicheskoe issledovanie farmakokinetiki i bioekvivalentnosti preparatov rizatriptana Relonova i Maksalt.

OBJECTIVE: Evaluation of the bioequivalence of the tested Relonova, tablets, 10 mg and Maxalt, tablets, 10 mg drugs on an empty stomach in healthy volunteers. MATERIAL AND METHODS: The pharmacokinetic analysis population included 40 volunteers, the safety analysis population included 40 volunteers. The average age of randomized volunteers (men - 20, women - 20) was 29.3±8.9 years, height 1.71±0.09 m, body weight 70.86±11.66 kg, mean BMI 24.18±2.81 kg/m2. The method used high performance liquid chromatography with tandem mass spectrometric detection. Statistical analysis of the obtained data was performed based on the assumption of a log-normal distribution of the parameters AUC0-72 and Cmax. RESULTS: The ratio of geometric means for the key pharmacokinetic parameters (AUC0-t, AUC0-inf and Cmax) of rizatriptan is close to 90%, CI is within the acceptable range for bioequivalent drugs (80-125%). The intrasubject variability (CVintra) for rizatriptan was 23.74% (Cmax), 10.94% (AUC0-t). The average profiles of the pharmacokinetic curves of rizatriptan when taking the test and reference drugs have similar shapes. Relonova and reference Maxalt are bioequivalent. CONCLUSION: The results of the study make it possible to recommend Relonova for further clinical study and wide practical application.

In Vivo Evaluation of Almotriptan malate Formulation through Intranasal Route for the Treatment of Migraine: Systematic Development and Pharmacokinetic Assessment.

Migraine headaches are usually intolerable, and a quick-relief treatment remains an unmet medical need. Almotriptan malate is a serotonin (5-HT1B/1D) receptor agonist approved for the treatment of acute migraine in adults. It is currently available in an oral tablet dosage form and has a Tmax of 1-3 h, and therefore, there is a medical need to develop a non-invasive rapidly acting formulation. We have developed an intranasal formulation of almotriptan malate using the quality-by-design (QbD) approach. A 2-factor 3-level full factorial design was selected to build up the experimental setting. The developed formulation was characterized for pH, viscosity, in vitro permeation, ex vivo permeation, and histopathological tolerance. To assess the potential of the developed formulation to produce a rapid onset of action following intranasal delivery, a pharmacokinetic study was performed in the Sprague-Dawley rat model and compared to the currently available marketed oral tablet formulation. For this, the LC-MS/MS bioanalytical method was developed and used for the determination of plasma almotriptan malate concentrations. Results of a pharmacokinetic study revealed that intranasal administration of optimized almotriptan malate formulation enabled an almost five-fold reduction in Tmax and about seven-fold increase in bioavailability in comparison to the currently available oral tablet formulation, suggesting the potential of developed almotriptan malate intranasal formulation in producing a rapid onset of action as well as enhanced bioavailability.

Pharmacokinetic Study of Frovatriptan Succinate Tablet After Single and Multiple Oral Doses in Chinese Healthy Subjects.

PURPOSE: The present report describes findings from a Phase I clinical study that evaluated the single- and multiple-dose pharmacokinetics of frovatriptan succinate tablet in Chinese healthy subjects. METHODS: A total of 24 healthy subjects were enrolled. In single-dose study, 2.5, 5, and 10 mg oral doses of frovatriptan succinate tablet were administrated. A 2.5 mg frovatriptan succinate tablet was administrated 12 times in 7 days in the multiple-dose study. Blood samples were collected at scheduled time points. RESULTS: The results in single-dose study indicated that the blood levels were proportional to the administered dose, with the mean Cmax and AUClast ranging from approximately 6.27 ng/mL-17.35 ng/mL and 92.52 h⋅ng/mL - 287.40 h⋅ng/mL over the dose range. In the multiple-dose study, moderate drug accumulation was noted, which was attributable to forvatriptan's long t1/2 of about 26.47 to 30.63 h. Gender differences were noticed in both single- and multiple-dose study; exposure PK parameters were consistently higher in female than in male. CONCLUSION: These pharmacokinetic evaluations in healthy Chinese subjects found that frovatriptan succinate tablet has an acceptable pharmacokinetic profile in Chinese subjects.

Quality by Design Approach for Preparation of Zolmitriptan/Chitosan Nanostructured Lipid Carrier Particles - Formulation and Pharmacodynamic Assessment.

PURPOSE: Zolmitriptan (ZT) is a selective serotonin agonist that is used for the treatment of migraine. It belongs to BCS class III with high solubility and low permeability. Besides, the drug is subjected to pre-systemic metabolism. Accordingly, new Zolmitriptan/chitosan nanostructured lipid carriers (ZT/CT NLCs) coated with Tween 80 (stealthy layer) have been developed to overcome such demerits. METHODS: The NLCs were developed by combining ultrasonication and double emulsion (w/o/w) techniques. The lipids were Gelucire and Labrasol. Herein, the quality by design (23 full factorial design) was scrupulously followed, where critical process parameters and critical quality attributes were predefined. The optimized formulation (F8) was fully characterized with respect to entrapment efficiency (%EE), percentage yield (% yield), particle size, size distribution (PDI), zeta potential (ZP), morphological appearance (TEM). In vitro release, stability study and pharmacodynamic evaluations were also assessed. The optimized freeze dried formula was dispensed in in situ gelling hard gelatin capsule encompassing pectin and guar gum for further in vitro and pharmacodynamic evaluations. RESULTS: The optimized spherical nanoparticles experienced high percentage EE and yield (78.14% and 60.19%, respectively), low particle size and PDI (343.87 nm and 0.209, respectively), as well as high negative ZP (-25.5 mV). It showed good physical stability at refrigerated conditions. The NLCs dispensed in in situ gelling hard gelatin capsule comprising pectin and guar gum experienced sustained release for 30 h and significantly maintained the pharmacological effect in mice up to 8 h (p < 0.001). CONCLUSION: ZT, a BCS class III drug that suffers from poor permeability and pre-systemic metabolism, was successfully maneuvered as nanostructured lipid carrier particles (NLCs). The incorporation of the NLCs in in situ gelling hard gelatin capsules fulfilled a dual function in increasing permeability, as well as sustaining the pharmacodynamic effect. This result would open new vistas in improving the efficacy of other class III drugs.

Evaluation of the Pharmacokinetic Interaction of Ubrogepant Coadministered With Sumatriptan and of the Safety of Ubrogepant With Triptans.

OBJECTIVE: To evaluate the potential for pharmacokinetic interaction and the safety and tolerability when ubrogepant and sumatriptan are coadministered in a Phase 1 study in healthy participants, and to inform the safety and tolerability of ubrogepant alone and in combination with triptans in Phase 3 trials in participants with migraine. BACKGROUND: Calcitonin gene-related peptide is a potent vasodilatory neurotransmitter believed to play a key role in the pathophysiology of migraine. Ubrogepant (UBRELVY™) is a potent and selective antagonist of the human calcitonin gene-related peptide receptor approved for the acute treatment of migraine. Sumatriptan is a serotonin receptor agonist and the most commonly used triptan for the acute treatment of migraine. Ubrogepant could be prescribed with triptans. DESIGN: The Phase 1 study was a single-center, open-label, randomized, 3-way crossover, single-dose, pharmacokinetic interaction study, where participants received each of 3 oral treatments with a 7-day washout period between treatments: single dose of ubrogepant 100 mg, single dose of sumatriptan 100 mg, and ubrogepant 100 mg plus sumatriptan 100 mg. Pharmacokinetic parameters were calculated using a model-independent approach. The ACHIEVE I and II trials were 2 multicenter, single-attack, randomized, Phase 3 trials in adults with a history of migraine with or without aura. Participants had the option to take a second dose of study medication or rescue medication to treat a nonresponding migraine or a migraine recurrence from 2 to 48 hours after the initial dose of study medication. Rescue medication options included acetaminophen, nonsteroidal anti-inflammatory drugs, opioids, anti-emetics, or triptans. Treatment-emergent adverse events were evaluated up to 30 days after the last dose in the Phase 1 and Phase 3 studies. RESULTS: Ubrogepant median time to maximum plasma concentration was delayed (3 hours [range: 1-5 hours] vs 1.5 hours [range: 1-4 hours]), mean maximum plasma concentration was reduced by 24% (coefficient of variation: 37.4%) when ubrogepant was coadministered with sumatriptan (n = 29) compared with ubrogepant administered alone (N = 30). No significant effect was observed on the area under the plasma concentration-time curve of ubrogepant. Sumatriptan area under the curve and maximum plasma concentration showed no significant change when sumatriptan was coadministered with ubrogepant (n = 29), but the sumatriptan time to maximum plasma concentration was delayed (1 hour [range: 0.5-5 hours] vs 3 hours [range: 0.5-6 hours]. No treatment-emergent adverse events were reported with the coadministration of ubrogepant 100 mg and sumatriptan 100 mg in the Phase 1 study. The pooled safety data from ACHIEVE trials (N = 1938) showed similar rates of treatment-related treatment-emergent adverse events between participants who took ubrogepant alone and participants who took ubrogepant and a triptan as a rescue medication (14.9% [53/355] vs 12.8% [5/39] in the ubrogepant 100 mg treatment group, respectively). CONCLUSIONS: Although there were slight alterations in ubrogepant pharmacokinetic parameters when coadministered with sumatriptan, such changes are expected to have minimal clinical relevance, especially because no changes were seen in sumatriptan area under the curve and maximum plasma concentration when coadministered with ubrogepant. Coadministration of ubrogepant with sumatriptan was well tolerated in healthy participants in the Phase 1 study, and coadministration of ubrogepant with triptans was well tolerated in participants with migraine in the Phase 3 trials. No new safety concerns for ubrogepant were identified across all trials.

Evaluation of OptiFlow™-MS/MS for bioanalysis of pharmaceutical drugs and metabolites.

Aim: Microflow tandem mass spectrometry-based methods have been proposed as options to improve sensitivity and selectivity while improving sample utility and solvent consumption. Here, we evaluate a newly introduced microflow source, OptiFlow™, for quantitative performance. Results/methodology: We performed a comparison of the OptiFlow and IonDrive™ sources, respectively, on the same triple quadrupole mass spectrometer. The comparison used a neat cocktail of commercially available drugs and extracted plasma samples monitoring midazolam and alprazolam metabolites. Microflow produced a 2-4× signal increase for the neat drug cocktail and a 5-10× increase for extracted plasma samples. Conclusion: The OptiFlow method consistently gave increased signal response relative to the IonDrive method and enabled a better lower limit of quantitation for defining phamacokinetics.

Pharmacokinetic study and brain tissue analysis of Zolmitriptan loaded chitosan nanoparticles in rats by LC-MS method.

INTRODUCTION: Migraine has recently become a major interest to the neuroscientists. Zolmitriptan is an effective medicine used in the treatment of migraine. The nasal spray was prepared from Zolmitriptan loaded chitosan nanoparticles and evaluated for pharmacokinetic properties. METHODS: In this study male Wistar albino rats weighing between 200 and 250 g were taken and divided into 4 groups with 6 rats in each group. Nasal spray containing Zolmitriptan loaded Chitosan nanoparticles were administered nasally (using specific inhalation mask) at a dose of 0.5 mg/kg as a test formulation and compared with the control groups which received either water for injection or marketed standard drug (Zolmist) or standard drug solution at a same dose. The pharmacokinetic parameters such as Cmax, Tmax, and brain tissue analyses for accumulation of drug were performed for Zolmitriptan by LC-MS method. RESULTS: Amount of drug in the plasma from the test formulation, standard marketed drug (Zolmist) and standard drug solution was found to be 41.37 ±â€¯2.31, 34.76 ±â€¯4.22 and 23.74 ±â€¯2.42 ng/ml at 10 min respectively, which indicated significantly (p < 0.05) greater amount of drug being delivered from the test formulation compared to the both standard groups. The amount of the drug (Zolmitriptan) present in brain tissue (Olfactory lobe) was found to be 15 ±â€¯0.08, 13 ±â€¯0.14 and 8 ±â€¯0.13 ng/g at 60 min for test formulation, marketed standard and standard drug solution respectively which indicates significantly (p < 0.05) higher amount of drug absorption in brain tissue from the test formulation compared to both the standard groups. CONCLUSION: Pharmacokinetics studies of nasal spray containing Zolmitriptan loaded chitosan nanoparticles proved rapid onset of action in animals and is promising in treatment of migraine.

Intranasal spray formulation containing rizatriptan benzoate for the treatment of migraine.

Rizatriptan produces antimigraine activity by acting as selective agonist of 5-HT1B and 5-HT1D receptors present on intracranial and extracerebral blood vessels. Absorption from oral tablet is slow with Tmax of approximately 1-1.5 h. A few attempts have been made to promote rapid absorption such as oral or sublingual films with limited success. The aim of our study was to develop intranasal spray formulation of rizatriptan with quick onset of action. Solubility was enhanced by a co-solvent system where we studied solubility of rizatriptan benzoate in pure solvents, binary and ternary mixtures. Binary and ternary co-solvents using ethanol, water, propylene glycol and polyethylene glycol resulted rizatriptan equivalent base solubility more than 60 mg/mL. Same co-solvents were used at different level to make nasal spray formulations and evaluated pharmacokinetics using beagle dog animal model. Nasal spray formulation containing 20% w/w ethanol exhibited highest exposure, where Cmax (312 ng/mL) reached in 5 min and maintained higher concentration than oral dose for more than 30 min.

In-vitro and in-vivo respiratory deposition of a developed metered dose inhaler formulation of an anti-migraine drug.

Enhancement of zolmitriptan bioavailability through development of micronized zolmitriptan pressurized metered dose inhaler (MDI) as an alternative to its traditional drug delivery systems. A reversed phase HPLC method for zolmitriptan determination was developed and evaluated. Micronized zolmitriptan MDI formulations were prepared using two different propellants. The prepared formulations were evaluated for mean shot weight, drug content, and leakage rate in addition to in-vitro deposition using next generation impactor where mass median aerodynamic diameter (MMAD), geometric standard deviation (GSD), fine particle dose, fine particle fraction (FPF), emitted dose (ED), and dispersibility were determined. The selected formulation was evaluated for in-vivo bronchial absorption in rats. The physicochemical characters of the prepared formulations were found to be dependent mainly on the vapor pressure of the used propellant. MDI formulation prepared with HFA 134a propellant was found to have the lowest MMAD (3.47 ± 0.65) with GSD of 2.3 ± 0.4. It also had the highest FPF (41.9), ED (89.26 ± 2.35) with dispersibility of 46.9%. This formulation, when applied to rats, resulted in faster Tmax (27 ± 5 min) with higher Cmax (1236 ± 116 ng/mL) and AUC(0-12) (3375 ± 482 ng/mL·h) over the oral tablet. Its relative bioavailability was 72.7% which was 1.25 times higher than the oral tablet relative bioavailability. Zolmitriptan MDI formulation was developed using micronized zolmitriptan powder without further modification or particle engineering. The developed formulation using HFA 134a propellant could be favorable alternative, with enhanced bioavailability, to zolmitriptan oral tablet for acute migraine treatment.

Design and optimization of kollicoat ® IR based mucoadhesive buccal film for co-delivery of rizatriptan benzoate and propranolol hydrochloride.

This work aimed to develop a mucoadhesive buccal film for potential co-delivery of rizatriptan benzoate (RB) and propranolol hydrochloride (PRH). Kollicoat ® IR, polyethylene oxide (PEO), hydroxypropyl methylcellulose (HPMC K4M), glycerol, stevia, and Aloe vera gel powder (AVgel powder) were used to prepare film by solvent casting method. In order to characterize and optimize formulations, Design-Expert software with central composite design (CCD) was used. The selected independent variables were concentrations of Kollicoat ® IR, PEO, glycerol, and AVgel powder. Five selected dependent variables were in vitro disintegration time, folding endurance, swelling ratio, and in vitro drugs release. Film with 50 mg PRH, 25 mg RB, 5 mg stevia, 63 mg HPMC K4M, 100 mg Kollicoat ® IR, 66.33 mg PEO, 0.22 ml glycerol, and 0.8 mg AVgel powder was selected as optimized formulation. The optimized film was characterized by scanning electron microscope (SEM), Fourier transform infrared spectroscopy (FTIR) and differential scanning calorimetry (DSC) to evaluate morphology, chemical structure, and physical properties of the film. The mechanical properties of optimized film were measured by Santam instrument. Ex vivo permeation were studied by Franz diffusion cell, while rat buccal mucosa was used as a model membrane. The optimized film with incorporation of AVgel powder as a natural permeation enhancer could transport 73.22% of PRH and 96.11% of RB over 100 min through rat buccal mucosa and showed no buccal mucosal damage after histopathological evaluation. Overall, the optimized film could be a potential candidate for the effective treatment of migraine.

Efficacy of ADAM Zolmitriptan for the Acute Treatment of Difficult-to-Treat Migraine Headaches.

OBJECTIVE: To understand the efficacy of zolmitriptan applied with Adhesive Dermally Applied Microarray (ADAM) in treating types of migraine (those with severe headache pain, the presence of nausea, treatment ≥2 hours after migraine onset, or migraine present upon awakening) that are historically considered to be less responsive to oral medications. BACKGROUND: ADAM is an investigational system for intracutaneous drug administration. In a pivotal Phase 2b/3 study (ZOTRIP, N = 321 in the modified intention-to-treat population), ADAM zolmitriptan 3.8 mg provided superior pain freedom and freedom from patients' usual most bothersome associated symptom (MBS), compared with placebo at 2 hours post-dose. We undertook a post hoc analysis of data from the ZOTRIP trial to examine these same outcomes in subsets of patients whose migraine characteristics have been associated with poorer outcomes when treated with oral medications. METHODS: The ZOTRIP trial was a multicenter, randomized, double-blind, placebo-controlled, parallel group Phase 2b/3 study conducted at 36 sites in the United States. Presented here are post hoc subgroup analyses of patients with nausea (n = 110) or severe pain (n = 72) at baseline, those whose treatment was delayed 2 or more hours after onset (n = 75), and those who awoke with migraine (n = 80). The Cochran-Mantel-Haenszel test was used to assess whether patients in the ADAM zolmitriptan 3.8 mg group had superior treatment outcomes compared with placebo. RESULTS: In patients with nausea, 2-hour pain freedom was achieved in 44% (26/59) in the ADAM zolmitriptan 3.8 mg group and 14% (7/51) in the placebo group (P = .005) (odds ratio = 5.11, 95% CI: 1.96-13.30), and 2-hour MBS freedom was achieved in 68% (40/59) in the active treatment group and 45% (23/51) of those receiving placebo (P = .009) (odds ratio = 2.86, 95% CI: 1.28-6.43). For those with severe pain, corresponding pain-free values were 26% (10/39) and 15% (5/33) (P = .249) (odds ratio = 2.14, 95% CI: 0.60-7.62), and MBS-free values were 64% (25/39) and 42% (14/33) (P = .038) (odds ratio = 2.86, 95% CI: 1.05-7.79). Among participants who awoke with migraine, 44% (16/36) and 16% (7/44) were pain-free in the ADAM zolmitriptan 3.8 mg and placebo groups, respectively (P = .006) (odds ratio = 4.29, 95% CI: 1.50-12.31), and 72% (26/36) vs 39% (17/44) were MBS-free, respectively (P = .003) (odds ratio = 4.40, 95% CI: 1.61-12.05). In those whose treatment was delayed ≥2 hours, pain freedom in the active treatment group and placebo group were 33% (12/36) and 10% (4/39), respectively (P = .017) (odds ratio = 4.33, 95% CI: 1.24-15.10), and MBS freedom was achieved in 69% (25/36) and 41% (16/39), respectively, in the delayed treatment group (P = .014) (odds ratio = 3.37, 95% CI: 1.27-8.95). No significant effects (overall interaction P = .353) were observed in logistical regression models of treatment by subgroup interaction. CONCLUSION: Severe pain, delayed treatment, awakening with a headache, and the presence of nausea are factors that predict a poorer response to acute migraine treatment. In these post hoc analyses of subgroups of patients with each of these characteristics in the ZOTRIP trial, participants receiving ADAM zolmitriptan 3.8 mg displayed nearly uniformly better headache responses (2-hour headache freedom and 2-hour MBS freedom) compared with those who received placebo.

Intranasal Drug Delivery of Frovatriptan Succinate-Loaded Polymeric Nanoparticles for Brain Targeting.

The objective of the present study was to develop polymeric nanoparticles (PNPs) of frovatriptan succinate for brain targeting by nasal route. Double emulsion method was used to increase the entrapment efficiency of hydrophilic drug, and formulation was optimized by central composite design to achieve critical quality attributes namely particle size, zeta potential, and entrapment efficiency. Optimized batch was evaluated for surface morphology, in vitro release, permeation across nasal mucosa, stability, histopathology, and brain tissue uptake study. Prepared PNPs were found to be smooth with particle size of 264.4 ± 0.04 nm, zeta potential -35.17 ± 0.07 mV, and 65.2 ± 0.06% entrapment efficiency. PNPs showed biphasic release pattern, initial burst release followed by sustained release up to 72 h. Ex vivo diffusion study using goat nasal mucosa at pH 6.8 revealed that PNPs permeation across nasal mucosa was about 3 times more than the pure drug solution, and quick delivery of PNPs in brain region was confirmed by fluorescence microscopic evaluation in male Wistar rats after intranasal administration. Histopathology studies further revealed integrity of nasal mucosa after treatment with PNPs. The investigation indicated that hydrophilic drug, frovatriptan succinate can be successfully entrapped in PNPs to target brain via nasal delivery, and thus it could be an effective approach for nose to brain delivery.

Differential pharmacokinetic drug-drug interaction potential of eletriptan between oral and subcutaneous routes.

1. Pharmacokinetic drug-drug interaction (DDI) data is important from a label claim either in combination drug usage or in polypharmacy situation. 2. Eletriptan undergoes first pass related metabolism through CYP3A4 enzyme to form pharmacologically active N-desmethyl metabolite. 3. Differential DDI interaction of the concomitant oral dosing of ketoconazole (20.1 mg/kg), a CYP3A4 inhibitor, with oral (4.2 mg/kg) or subcutaneous dose (2.1 mg/kg) of eletriptan was evaluated in male Sprague Dawley rats. Serial pharmacokinetic samples were collected and simultaneously analysed for eletriptan/N-desmethyl eletriptan using validated assay. Non-compartmentally derived pharmacokinetic parameters for various treatments were analysed statistically. 4. After oral eletriptan in presence of ketoconazole, Cmax (40 vs. 32 ng/mL alone) and AUCinf (81 vs. 24 ng.h/mL alone) of eletriptan increased; the formation of N-desmethyl eletriptan decreased (Cmax=1.1 ng/mL, 3.9%) with ketoconazole as compared to without treatment (Cmax=3.7 ng/mL, 11.2%). After subcutaneous eletriptan in presence of ketoconazole, there was no change in Cmax (153 vs.152 ng/mL) or AUCinf (267 vs. 266 ng.h/mL) of eletriptan. Formation of N-desmethyl eletriptan after the subcutaneous dose was determined at few intermittent time points with/without ketoconazole. 5. Preclinical data support differential DDI of eletriptan when dosed oral vs. subcutaneous, which need to be evaluated in a clinical setting.

Study of the in vitro and in vivo metabolism of 4-HO-MET.

4-Hydroxy-N-methyl-N-ethyltryptamine (4-HO-MET) is a new psychoactive substance (NPS) of the chemical class of tryptamines. It shows structural similarities to the endogenous neurotransmitter serotonin, and is a serotonergic hallucinogen, affecting emotional, motoric, and cognitive functions. The knowledge about its biotransformation is mandatory to confirm the abuse of the substance by urine analysis in forensic cases. Therefore, phase I metabolites were generated by the use of the pooled human liver microsomes (pHLM) in vitro model and analyzed by high-performance liquid chromatography high-resolution tandem mass spectrometry with information-dependent acquisition (HPLC-IDA-HR-MS/MS). Furthermore, three authentic urine samples was analyzed and results were compared: 12 different in vitro and 4 in vivo metabolites were found. The predominant biotransformation steps observed in vitro were mono- or dihydroxylation of 4-HO-MET, besides demethylation, demethylation in combination with monohydroxylation, formation of a carboxylic acid, deethylation, and oxidative deamination. In vivo, monohydroxylation, and glucuronidation were detected. A metabolic pathway based on these results was proposed. For the analysis of urine samples in forensic cases, the N-oxide metabolite and the HO-alkyl metabolite are recommended as target compounds, besides the glucuronides of 4-HO-MET and the parent compound 4-HO-MET itself.

A novel nasal almotriptan loaded solid lipid nanoparticles in mucoadhesive in situ gel formulation for brain targeting: Preparation, characterization and in vivo evaluation.

This work aimed at designing efficient safe delivery system for intranasal (IN) brain targeting of the water soluble anti- migraine drug Almotriptan malate (ALM). Solid lipid nanoparticles (SLNs) were prepared by w/o/w double emulsion-solvent evaporation method. Selection of the optimized SLNs formula was based on evaluating particle size (PS), poly dispersity index (PDI) and entrapment efficiency (%EE). Optimized formula exhibited acceptable ranges; PS of 207.9 nm, PDI of 0.41 and %EE of 50.81%. Poloxamer 407 (Plx) at different concentrations (16%, 18%, 20% w/v), with different mucoadhesive polymers (Carbopol-974P, Na alginate, Na-CMC) were evaluated for gelling time and temperature, pH and mucoadhesion. The chosen mucoadhesive in-situ gel formula; 18% Plx 407 based-0.75%w/v Na-CMC, showed acceptable results, so that the optimized SLNs formula was further dispersed in it and evaluated for in vitro release, stability, in vivo and pharmacokinetics studies. Biomarkers' evaluation and histopathological examination were also investigated. Results revealed rapid ALM brain delivery of the optimized formula; Brain/blood ratios at 10 min. for NF (SLNs based IN in-situ gel), ND (Free ALM IN in situ gel) and ALM i.v. (ALM IV solution) were 0.89, 0.19 and 0.31, respectively. Toxicological results confirmed the safety of NF for nasal administration. The achieved out comings are encouraging for further clinical trials of the developed system in humans in future research.

Redox-Responsive Polymer with Self-Immolative Linkers for the Release of Payloads.

Previous couplings of corrosion inhibitors to redox-responsive polymers via covalent bonding suffer from several drawbacks. It is presented here novel redox-responsive polymer-corrosion inhibitor conjugates that contain self-immolative linkers in their side chains. Very fast redox-induced release of tryptamine, a drug and a corrosion inhibitor, is observed after applying a reductive trigger.

Pharmacokinetics and Skin Tolerability of Intracutaneous Zolmitriptan Delivery in Swine Using Adhesive Dermally Applied Microarray.

Adhesive Dermally Applied Microarray (ADAM) is a new drug-delivery system that uses microprojections (340-µm long) for intracutaneous drug self-administration. We formulated zolmitriptan, a well-accepted and commonly used migraine medication, for administration using ADAM. In vivo studies were conducted in female prepubescent Yorkshire pigs using ADAM 1.9-mg zolmitriptan applied to the inner thigh and left in place for 1 h. Pharmacokinetic studies showed that the ADAM 1.9-mg zolmitriptan was delivered with high efficiency (85%) and high absolute bioavailability (77%). Furthermore, in vivo evaluation showed a rapid systemic absorption with a median Tmax of 15 min. Skin biopsies of the treatment sites showed a mean depth of microprojection penetration of 105.4 ± 3.6 µm. Mass spectrometry imaging showed that the zolmitriptan after 1 h of patch wear time was predominantly localized to the dermis. ADAM zolmitriptan was well tolerated with a transient mild-to-moderate erythema response. The findings in these studies, particularly the rapid zolmitriptan absorption profile after intracutaneous administration, provided validation to advance ADAM zolmitriptan development.

Pharmacokinetics and tolerability of eletriptan hydrobromide in healthy Korean subjects.

BACKGROUND: Migraine is one of the most common headache disorders that greatly affect the quality of life. Selective serotonin (5-HT) receptor agonists such as triptamine-based drugs called triptans are used for treatment of migraine. PURPOSE: This study aimed to evaluate the pharmacokinetic (PK) and tolerability profiles of eletriptan hydrobromide (eletriptan HBr), a selective 5-hydroxytryptamine (also known as serotonin) 1B/1D receptor agonist, in Koreans and compare the results to those observed in non-Koreans in a previously published study. PATIENTS AND METHODS: A randomized, open-label, single, and repeated-dose study was conducted in 16 healthy Korean male subjects using a four-treatment, four-period, and four-sequence crossover design (NCT01139515). The subjects received one of the following four treatments in each period: a single dose of 20, 40, 80 mg eletriptan HBr or a repeated oral dose of 40 mg 2 h apart. Blood samples were collected before and up to 26 h after dosing for quantification of plasma eletriptan concentration by high-performance liquid chromatography tandem-mass spectrometry. The PK parameters were estimated using noncompartmental methods. Ethnicity differences between Korean and non-Korean subjects were identified using geometric mean ratios and 90% confidence intervals (CIs) of dose-normalized maximum plasma concentration (Cmax) and dose-normalized area under the plasma concentration versus time curve from 0 h to the last measurable concentration (AUC0-t). RESULTS: After single-dose administration of eletriptan HBr to Korean subjects, the mean Cmax and AUC0-t increased linearly with dose. Comparable total systemic exposures were observed in the 2 h apart 40 mg repeated and single 80 mg dose. The geometric mean ratios (90% CIs) of the dose-normalized Cmax and AUC0-t of Korean subjects were similar to those of non-Korean subjects reported in the literature. The adverse events observed were transient and mild in severity. CONCLUSION: Eletriptan HBr showed linear PK and was well tolerated in Korean subjects. The PK and tolerability of eletriptan HBr did not differ between Korean and non-Korean subjects.

A coupled bimodal SPECT-CT imaging and brain kinetics studies of zolmitriptan-encapsulated nanostructured polymeric carriers.

The present investigation deals with preparation and characterization of anti-migraine zolmitriptan (ZMT) nanostructured polymeric carriers for nose to brain drug targeting. The drug-loaded colloidal nanocarriers of ZMT were prepared by modified ionic gelation of cationic chitosan with anionic sodium tripolyphosphate and characterized for particle size, zeta potential, and entrapment efficiency. Further, in order to investigate nose to brain drug targeting, biodistribution, and brain kinetics studies were performed using 99mtechnetium radiolabeled nanocarriers (99mTc-ZMTNP) in Swiss albino mice. The results were compared with intranasal pure drug solution (99mTc-ZMT) and intravenous nanocarriers (99mTc-ZMTNP). A single photon emission computerized tomography (SPECT) radioimaging studies were also carried out to visualize and confirm brain uptake of nanocarriers. The optimized nanocarriers showed particle size of 161 nm, entrapment efficiency of 80.6%, and zeta potential of + 23.7 mV. The pharmacokinetic parameters, Cmax, and AUC0-∞ values for ZMT concentration in the brain expressed as percent radioactivity per gram of brain in intranasal and intravenous route of administration were calculated. The brain Cmax and AUC0-∞ values found in three groups, intranasal 99mTc-ZMTNP, intranasal 99mTc-ZMT, and intravenous 99mTc-ZMTNP were (0.427 and 1.889), (0.272 and 0.7157), and (0.204 and 0.9333), respectively. The higher Cmax values of intranasal 99mTc-ZMTNP suggests better brain uptake as compared to other routes of administration. The significant higher values of nose to brain targeting parameters namely, drug targeting index (5.57), drug targeting efficiency (557.08%), and nose to brain drug direct transport (82.05%) confirmed drug targeting to brain via nasal route. The coupled bimodal SPECT-CT scintigrams confirm the brain uptake of intranasal 99mTc-ZMTNP demonstrating major radioactivity accumulation in brain. This study conclusively demonstrated the greater uptake of ZMT-loaded nanocarriers by nose to brain drug targeting, which proves promising drug delivery system.