Solid-state characterization of AG337 (Thymitaq), a novel antitumor drug

AG337 (Thymitaq) is an antitumor compound synthesized by Agouron Pharmaceuticals, Inc., using protein structure-based drug design. AG337 is a hydrochloride salt with a molecular formula of C14H12N4OS.2HCl. This compound was subjected to thermal analyses, Karl Fischer titrimetry, powder X-ray diffractometry, scanning electron microscopy, and FTIR. On the basis of the Karl Fischer and thermogravimetric analysis, it was conclude to be a dihydrate. The differential scanning calorimetric studies revealed, that on heating, AG337 dehydrates and form a metastable form with a melting point of 213 degrees C followed by crystallization into a stable form at 261 degrees C. This stable form was finally melted at 312 degrees C with decomposition. On the basis of the FTIR and HPLC studies, it was concluded that the final exothermic peak at 320 degrees C was due to sample decomposition. The powder X-ray diffraction studies confirmed the existence of these two polymorphs of AG337. Scanning electron microscopic studies revealed that the crystal habits of both the polymorphs were quite different. FTIR spectra of both the polymorphs showed pronounced difference in the range of 600-1800 cm-1.     

Effect of betotastine besilate (TAU-284), a novel anti-allergic agent, on experimental allergic rhinitis

We investigated the effect of betotastine besilate (betotastine) on the experimental allergic rhinitis. The oral administration of betotastine (1, 3 and 10 mg/kg) inhibited the increase in dye leakage during and after the nasal perfusion of antigen in actively sensitized rats. It also prevented the increase in intranasal pressure induced by topically applied histamine in non-sensitized guinea pigs. Cetirizine and terfenadine dose-dependently inhibited the increase in a similar manner. Ketotifen (0.01-0.3 mg/kg, p.o.) inhibited the increase more than 50% at 0.01 mg/kg. The ID50s of ketotifen, cetirizine, betotastine and terfenadine for this model were more than 0.01 mg/kg, 0.01 mg/kg, 0.03 mg/kg and 0.5 mg/kg, respectively. Furthermore, in actively sensitized guinea pigs, nasal airway resistance showed a biphasic increase after the topical antigen challenge to the nasal cavity; the first peak at 0.5 hr and a second peak at 4 hr. Both the responses of first and second peaks were significantly inhibited by orally administered betotastine besilate, and its inhibitory effect on the second peak was the strongest among drugs tested. Since betotastine showed significantly inhibitory effects in experimental allergic rhinitis models, it was suggested to show a good efficacy for the treatment of allergic rhinitis clinically.     

Cardiovascular effects of nepicastat (RS-25560-197), a novel dopamine beta-hydroxylase inhibitor

PURPOSE: The aim of the present study was to develop a standard protocol for evaluating peak oxygen uptake and anaerobic threshold during upper body work by cross-country skiers. METHODS: All tests were performed on a specially developed ski ergometer and incorporated the double poling technique. In series I, continuous and discontinuous protocols for measuring VO2peak at different inclinations of the ski ergometer were performed. In series II, a protocol for evaluating anaerobic threshold during upper body work was established. Eleven well trained regional male cross-country skiers participated in the study. All tests in each series were carried out during a period of 14 d. RESULTS: VO2peak did not differ using continuous or discontinuous protocol while working on the ski ergometer. Inclination was found to influence VO2peak, which was reduced at 7 degrees compared with 3 degrees, 5 degrees, and 6 degrees. Th(an) working on the ski ergometer was reached at a power output, VO2, or fc, which gave on average a blood lactate concentration of 1.8 mmol.L-1 higher than those found after the warm-up period during a graded protocol. CONCLUSIONS: Testing only the traditional Th(an) and VO2max while running on a treadmill hides important determinants of endurance in cross-country skiing as shown by that no correlation was found between VO2max and VO2peak in the present study.     

Urodynamic and other effects of tolterodine: a novel antimuscarinic drug for the treatment of detrusor overactivity

Tolterodine, a novel compound intended for treatment of urgency and urge incontinence, has been characterized as a potent muscarinic receptor antagonist in pharmacological in vitro and in vivo studies. In cats, tolerodine was shown to reduce bladder pressure at doses significantly lower than those affecting salivation. To predict clinical effectiveness, an open pilot study was performed in healthy male volunteers. Efficacy was measured by cystometry and by spontaneously reported effects after administration of a single oral dose of tolterodine, 6.4 mg, given as a water solution. Tolterodine had distinct inhibitory effects on urinary bladder function, both at 1 and 5 hours post-dose. At 1 hour, but not at 5 hours post-dose tolterodine also significantly reduced stimulated salvation. In addition to the objectively demonstrated changes in urodynamic parameters, most volunteers experienced voiding difficulties. No significant changes in blood pressure, heart rate, or near point of accommodation were registered. Tolterodine, in the dosage used, was both objectively and subjectively shown to exert a marked inhibitory effect on micturition in healthy subjects, and the data suggest a more pronounced effect on bladder function than on salivation.     

MST-16, a novel derivative of bis(2,6-dioxopiperazine), synergistically enhances the antitumor effects of anthracyclines

OBJECTIVE: The aim of this study was to evaluate whether toluene, like many other organic solvents and solvent mixtures, could impair color vision. SUBJECTS AND METHODS: We investigated color vision impairment in three groups of workers, two groups occupationally exposed to toluene and a nonexposed group. The first exposed group, group E1, comprised 41 workers (median value of toluene in air 35.00 ppm, range 11.3-49.3 ppm) and the second exposed group, group E2, comprised 32 subjects (median value of toluene in air 156.00 ppm, range 66.0-250.0 ppm). The nonexposed group, group NE, comprised 83 subjects. Color vision was evaluated by the Lanthony D-15 desaturated test according to Verriest's classification: type I, loss in the red-green range; type II, loss in the blue-yellow and red-green ranges, and type III, loss in the blue-yellow range. Subjects were classified as dyschromates if specific acquired loss was determined in at least one eye. In both exposed groups, exposure was evaluated by measurement of the concentration of toluene in the ambient air and in the blood. In group E2, level of hippuric acid and orthocresol in urine after the work shift were also determined. The Mann-Whitney U-test, t-test, chi 2-test, and Spearman's rank correlation and multiple regression analysis were used for statistical analysis. RESULTS: Type III dyschromatopsia was detected in all groups examined: 26.6% of the workers in group NE, 31.7% of those in group E1, and 50% of those in group E2. As many as 15.6% of the workers in group E2, 4.8% of those in group E1, and only 1.2% of those in group NE had type II dyschromatopsia. A statistically significant difference in the prevalence of total dyschromatopsia (type III + type II) was established among the three examined groups together (chi 2 = 14.13; df = 2; P < 0.01), between group E2 and group E1 (chi 2 = 4.96; P < 0.05), and between group E2 and group NE (chi 2 = 12.50; P < 0.005), whereas no significant difference was found between groups E1 and NE. Type III dyschromatopsia was significantly correlated with age in group NE (P < 0.01) and in group E1 (P < 0.005). In group E2, both type II (P < 0.05) and type III dyschromatopsia correlated with toluene in ambient air and with the duration of exposure to toluene (both P < 0.005). In group E2, total dyschromatopsia correlated significantly with toluene in ambient air and in blood (both P < 0.05) as well as with hippuric acid in urine after the work shift (P < 0.001). CONCLUSION: This study suggests that toluene can impair color vision.     

A survey of the effects of a drug promotion campaign

A postal survey which tried to test the impact of a drug-promotion campaign is described. One hundred and twenty randomly-selected general practitioners were circulated and a 74.8 per cent response was obtained. Of the responders, 92 per cent were aware of the existence of the preparation, and of these responders 69 per cent were unaware either of the pharmacologically approved name of the drug, or the fact that its pharmacologically active constituent was already available under another brand name.     

A novel anti-inflammatory drug, SDZ ASM 981, for the topical and oral treatment of skin diseases: in vivo pharmacology

There is a need for safe and effective therapies for inflammatory skin diseases. Current topical and systemic treatment of psoriasis is effective but suffers from side-effects or is inconvenient. The therapeutic armamentarium for atopic dermatitis is very limited and far from satisfactory. In vivo preclinical data are presented for SDZ ASM 981, a novel ascomycin macrolactam derivative with high anti-inflammatory activity. Anti-inflammatory activity was observed in mouse, rat and pig models of allergic contact dermatitis. In the pig model, topical SDZ ASM 981 was as effective as the ultrapotent corticosteroid clobetasol-17-propionate, and when compared with a series of commercial topical corticosteroid preparations, 0.1% SDZ ASM 981 had equivalent efficacy to clobetasol-17-propionate (0.05%), the most potent product on the market. Unlike the corticosteroid, however, SDZ ASM 981 did not cause skin atrophy in pigs. SDZ ASM 981 potently inhibited allergic contact dermatitis in mice and rats when given systemically, and oral treatment was more effective than cyclosporin A in rats. Furthermore, SDZ ASM 981 has a low potential for affecting systemic immune responses, as demonstrated in rat models of localized graft vs. host reaction and allogeneic kidney transplantation. Preclinical results suggest that SDZ ASM 981 has the potential to be a well-tolerated and effective drug for topical as well as oral treatment of inflammatory skin diseases.     

A novel HPLC method for determination of EDTA in a cataract inhibiting ophthalmic drug

A novel HPLC method for determination of EDTA in a cataract inhibiting ophthalmic drug product has been developed. In this method EDTA was converted to Cu(II)EDTA complex, using Cu + 2 containing mobile phase, after injection into the chromatographic system. This allowed complexation of EDTA with Cu + 2 without interference from formulation ingredients. The Cu(II)EDTA complex was separated from drug substance, impurities, degradants and other formulation excipients by a 250 x 4.1 mm anion exchange column and detected at UV wavelength 250 nm. The mobile phase consisted of 2 mM cupric nitrate, 11 mM nitric acid, and 25% (v/v) acetonitrile at pH 3.0. This stability indicating assay has been validated and shown to be specific, linear, precise, accurate and rugged for routine EDTA analysis.     

Screening for novel drug effects with a microphysiometer: a potent effect of clofilium unrelated to potassium channel blockade

Changes in cellular metabolism in response to pharmacological compounds can be detected using a biosensor known as a microphysiometer, which measures the rate at which cells release acidic metabolites. We have applied this technique to screen for effects of cation channel blockers on the metabolism of a variety of human and murine cell lines. At concentrations sufficient for cation channel blockade, most of these drugs have little or no effect on cellular metabolism as measured by acid release. In contrast, the potassium channel blocker clofilium triggers sustained increases in acid release at low (> or = 3 microM) concentration. Acid release persists in media containing high (150 mM) extracellular potassium. This release is not triggered by chemically similar potassium channel blockers. Thus these metabolic effects reflect a potent and specific function of clofilium which is unrelated to potassium channel blockade. Attempts to identify physiological correlates to this response revealed that low concentrations of clofilium but not other potassium channel blockers cause lymphoma apoptosis. These findings demonstrate that effects of clofilium found in other studies may not be due to changes in plasma membrane potassium conductance.     

Induction of cytochrome P4503A by the antiglucocorticoid mifepristone and a novel hypocholesterolaemic drug

An acidic proteinase was purified from human kidney cortex. The enzyme showed a molecular mass of 31 kDa by SDS-PAGE, 36 kDa by gel filtration, and isoelectric points of 5.2 and 6.1. The optimum pH for hydrolysis of bovine hemoglobin was about 3.5. Reverse-phase HPLC analysis of the incubation mixture of the enzyme with human plasma showed the presence of an active peptide on rat uterus muscle with the same retention time as the methionyl-lysyl-bradykinin (MLBK) standard. The specific activities were 2.91 micrograms MLBK equivalent mg-1.min-1 at pH 3.5 and 2.15 micrograms MLBK equivalent mg-1.min-1 at pH 6.0. All the enzymatic activities of this human kidney proteinase were inhibited by pepstatin A. Intramolecularly quenched fluorogenic substrates with amino acid sequences of human kininogen were used to determine the cleavage points. On the N-terminal sequences (Abz-Leu-Met-Lys-Arg-Pro-Eddnp and Abz-Met-Ile-Ser-Leu-Met-Lys-Arg-Pro-Eddnp) the cleavage occurred at the Leu-Met linkage, and on the C-terminal sequences (Abz-Phe-Arg-Ser-Ser-Arg-Eddnp and Abz-Phe-Arg-Ser-Ser-Arg-Gln-Eddnp) the cleavage occurred at the Arg-Ser linkage. Abz-Arg-Pro-Pro-Gly-Phe-Ser-Pro-Phe-Arg-Ser-Ser-Arg-Gln-Eddnp++ + was hydrolyzed by the renal acidic proteinase and yielded the peptide Abz-Arg-Pro-Pro-Gly-Phe-Ser-Pro-Phe-Arg (Abz-bradykinin). Kinectic parameters were determined using Abz-Met-Ile-Ser-Leu-Met-Lys-Arg-Pro-Eddnp (K(m) = 0.69 +/- 0.08 microM; Kcat = 0.052 +/- 0.0095 s-1; Kcat/K(m) = 0.075 +/- 0.005 microM-1.s-1) and Abz-Phe-Arg-Ser-Ser-Arg-Gln-Eddnp (K(m) = 1.56 +/- 0.16 microM; Kcat = 0.0048 +/- 0.0001 s-1; Kcat/K(m) = 0.003 +/- 0.0003 microM-1.s-1). Human liver cathepsin D had no activity on C-terminal sequences and human pepsin hydrolyzed them at the Ser-Ser bond. The results suggest that the renal acid proteinase is distinct from human pepsin and human liver cathepsin D and releases MLBK from human kininogen.     

Characterization of neurotoxic effects of NMDA and the novel neuroprotection by phytopolyphenols in mice.

Excitotoxicity plays a major role in various neurological disorders. In this study, we explored the behavioral and neurotoxic effects of intraventricular NMDA administration in mice. After NMDA injection, acute seizures were followed by impairments in locomotor activity, motor performance on a rotarod, and climbing ability. Mice killed 1 day after NMDA administration showed increased synaptosomal reactive oxygen species ROS production and calcium concentration and decreased mitochondrial membrane potential, mitochondrial reductase activities, and neuronal membrane Na+, K+ -ATPase and mg2+ -ATPase activities. One and 3 days after excitotoxic injury, Golgi stains showed that dendritic length and spine density were significantly decreased in neurons of the hippocampal dentate gyrus. Some mice received honokiol, tea polyphenol plus memantine, and honokiol plus memantine prior to NMDA treatment; the occurrence of generalized seizures was attenuated, seizure scores were reduced, latency to generalized seizures was prolonged, and motor impairments were lessened. Moreover, all of the neurochemical changes of the synaptosomes were also ameliorated. In conclusion, the behavioral and neurotoxic effects of intracerebroventricular injection of NMDA were ameliorated by treatment with honokiol alone or combined treatment with either tea polyphenol plus memantine or honokiol plus memantine, but only partly by either tea polyphenol or memantine alone. The therapeutic potential of these neuroprotective regimens in treating excitotoxicity-related diseases merits for further investigation. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Prevalence of allergic diseases in schoolchildren in Krakow and Poznan (based on a standardized ISAAC questionnaire)

The study population included children aged 6-7 and 13-14 years from primary schools in Kraków (2302 and 2967 children respectively) and Poznań (3132 and 4069 children respectively). The prevalence was assessed using ISAAC questionnaire. In younger age group the number of children with diagnosed asthma and presenting asthma symptoms was significantly higher in Kraków than in Poznań. In older age group higher percentage was observed in Kraków in relation to wheeze ever and nocturnal cough during last year. Pupils from Kraków had symptoms of allergic rhinitis and were diagnosed as allergic rhinitis more frequently than from Poznań. Symptoms suggestive for skin allergy were more often observed in Kraków, but the differences were significant in relation to symptoms during last year in both age groups and in relation to symptoms ever in older age group. Our study revealed discrepancy between the prevalence of symptoms of asthma and allergic rhinitis and the prevalence of established diagnosis.     

Studies on the reliability of a novel absorption-lipophilicity approach to interpret the effects of the synthetic surfactants on drug and xenobiotic absorption

Some theoretical principles of the absorption/lipophilicity approach, which attempts to explain the effects of the synthetic surfactants on xenobiotic and drug intestinal absorption, are reviewed and experimentally checked by examining the correlations obtained between "in situ" absorption constants, ka, found in rat colon, and "in vitro" lipophilicity indexes, K', for two compound series (secondary aliphatic amines and phenylalkylamines) in the absence and in the presence of the nonionic surfactant Polysorbate 80, in the intestinal perfusion fluid. Evidence is given for the following actions of the synthetic surfactant: at its critical micelle concentration (CMC), it increases the polarity of the absorbing membrane and, at the same time, it disrupts the aqueous stagnant diffusion layer adjacent to the mucosal barrier. When a supramicellar concentration (SMC) is used, the above actions are almost totally masked by the micellar solubilization of the tested amines, which decreases their absorption constants relative to those found at CMC, as markedly as solute lipophilicity increases. As a consequence of these actions, the correlations between ka and K', which are clearly hyperbolic in free solution, become potential in the presence of the surfactant at its CMC, whereas at SMC a bilinear correlation is obtained. Absorption via lipophilic ionized species seems to take place for both compound series. Mathematical and physicochemical interpretations of this behaviour are outlined, and biopharmaceutical implications of these phenomena are discussed.     

Early phase II study of KRN8602 (MX2), a novel anthracycline derivative for acute leukemia

We performed an early phase II study of KRN8602, a new anthracycline derivative for refractory or relapsed acute leukemias. KRN8602 was given at a dose of 15 mg/m2 for 3 to 5 consecutive days, repeating every 3-4 weeks. Among 53 patients entered in the study, 51 were evaluable for safety, and 46 were evaluable for efficacy. The response rate at schedules of 3 and 4 consecutive days was 9.1% (1 PR/11), while that at a schedule of 5 consecutive days was 22.9% (3 CR + 5 PR/35). With the 5 consecutive day schedule, the response rates were 21.4% (1 CR + 2 PR/14) for acute myelogenous leukemia and 29.4% (2 CR + 3 PR/17) for acute lymphocytic leukemia, but no response was observed in 4 patients with blastic crisis of chronic myelogenous leukemia. Major toxicities were nausea/vomiting and anorexia, however, all these toxicities were clinically manageable. From these results it is concluded that KRN8602 is effective against acute leukemias, and the optimal dose is 15 mg/m2 for 5 consecutive days.     

The use of antiadhesins--a new prospective trend in preventing and treating infectious diseases (a foundation for the technologies for creating drugs in the 21st century)

The state and prospects of research on creation of antiadhesins--new generation drugs for preventing and treatment of infectious diseases, are analyzed in the paper. The elaboration of such drugs is based on the profound knowledge about the nature of viral, bacterial, fungal and other infectious agents of diseases, molecular mechanisms of their interactions with the affected organs and tissues which are based on the processes of carbohydrate-protein recognizing. Rapid development of such fields of science as glycobiology and lectinology has created the preconditions for artificial synthesis of oligosaccharides which mimicked the receptors and can interact with adhesive structures of the disease agents more intensively than their natural analogs and block them. This makes the interaction of the latter with the affected organs impossible. The intensive work on elaboration of natural drugs: antiadhesins, is carried out in most countries. Adhesins are not harmful for people and cannot provoke the development of resistance to them in the disease agents. Till recently Ukraine belonged to the number of countries where the fields of science mentioned above were intensively developed but, in connection with the present stagnation of science and even the artificial hindering of its development, the country gradually losses the position of a leader. Hence, one can conclude that when 10-15 years later the market of pharmaceutical products will be filled with antiadhesins, our country will not be on the list of their producers, if the authorities will spend funds to buy foreign drugs as before instead of stimulating the development and production of the home ones.     

A comparative study of the analgesic and respiratory effects of N-allylnorcodeine (nalodeine), nalorphine, codeine and morphine

In this comparative study, the abdominal constriction test was used to determine analgesia in mice, and the body plethysmograph was used to study respiratory effects of nalodeine, nalorphine, naloxone, codeine, morphine and various agonist-antagonist combinations in rats. The analgesia dose-response curves for the surrogate pairs, nalodeine-nalorphine and codeine-morphine, were parallel but had significantly different slopes. Naloxone was a more potent antagonist of morphine and codeine than of nalorphine and nalodeine. In antagonizing morphine and codeine analgesia, naloxone was the most potent antagonist, nalorphine had a biphasic effect with decreasing activity at higher doses and nalodeine was not an antagonist. Moderate doses of nalorphrine depressed minute volume largely by their effect on tidal volume, but high doses stimulated respiratory rate and therefore had less effect on minute volume. Nalodeine depressed minute volume by depressing tidal volume, since all doses initially stimulated and then variably affected respiratory rate. Metabolic rate was not increased by either drug short of convulsant doses. Nalodeine depresses the ventilatory response to CO2 and weakly antagonizes the respiratory depressant actions of morphine.     

Gamma sterilization of a semi-solid poly(ortho ester) designed for controlled drug delivery--validation and radiation effects

Radiation sterilization is becoming increasingly popular for the sterilization of many pharmaceutical products. Although this technique is not limited to the sterilization of polymers, it is probably the most suitable method for such materials. This method however suffers several drawbacks. The sterilization of a product must lead to a safety level of 10(-6), i.e. one chance in a million to find a contaminated sample. In many cases, this assurance of sterility can be achieved by using a uniform treatment dose of 2.5 Mrad, recommended by the pharmacopeia. We investigated the possibility of using doses of radiation inferior to 2.5 Mrad to sterilize a semi-solid poly(ortho ester) (POE) developed for use as carrier in controlled drug delivery. After determination of the initial bioburden, the polymer was intentionally contaminated with the bioindicator Bacillus pumilus E 601. Following exposure to gamma irradiation, the D10 value of the radio resistant bioindicator was determined. Using the initial contamination value, the reduction factor D10 and the safety level, it is possible to calculate an optimal sterilizing dose for POE. All polymers are affected by ionizing radiation and the amount of radiation which produces a significant change in properties may vary from one polymer to the other. A molecular weight and dynamic viscosity decrease resulting from backbone cleavage was observed for this POE at a dose lower than 2.0 Mrad. Evaluation of the structure using 1H-NMR, 13C-NMR and IR analysis shows that for doses higher than 2.0 Mrad, another degredation process takes place.(ABSTRACT TRUNCATED AT 250 WORDS)     

Characterization of the independent and combined effects of two inhibitors on oxidative drug metabolism in rat liver microsomes

To evaluate how two inhibitors influence oxidative drug metabolism, this study investigated the inhibitory effects of mexiletine with cimetidine and mexiletine with lidocaine, both individually and in combination, on the oxidative metabolism of two probe substrates, aminopyrine and aniline in rat liver microsomes. Mexiletine was a competitive inhibitor of aminopyrine N-demethylation, whereas cimetidine was a mixed type of inhibitor (Ki = 2.00 +/- 0.04 and 0.20 +/- 0.02 mM, respectively). For aniline hydroxylation, mexiletine exhibited a mixed type of inhibition, whereas lidocaine was a noncompetitive inhibitor (Ki = 0.60 +/- 0.07 and 8.50 +/- 0.12 mM, respectively). The combined inhibition of either mexiletine with cimetidine or mexiletine with lidocaine on aminopyrine and aniline metabolism was close to the fully additive effects of the individual compounds when their individual concentrations were below a 2-fold Ki concentration, regardless of the apparent kinetic inhibition type. The combined inhibition was less than fully additive when the individual concentrations were twice the Ki or above. These results demonstrate that, when two inhibitors of oxidative drug metabolism are combined, both the Ki values and the concentrations of inhibitors play important roles in determining the extent of additive inhibition of enzyme activity.