First-In-Human Study on Pharmacokinetics, Safety, and Tolerability of Single and Multiple Escalating Doses of PA9159 Nasal Spray, a Highly Potent Glucocorticoid in Healthy Chinese Volunteers.

OBJECTIVE: PA9159 (previously named VSG159) is a structurally novel and highly potent glucocorticoid that plays a role in the late development of autoimmune and inflammatory diseases. The current first-in-human ascending-dose study of the PA9159 nasal spray was conducted in healthy Chinese volunteers to evaluate its pharmacokinetics, safety, and tolerability. In addition, the effects of PA9159 on serum cortisol secretion were investigated. METHODS: This was a double-blinded, randomized, placebo-controlled clinical study that included four single-dose groups in the single ascending dose cohort (SAD) and two multiple-dose groups in the multiple ascending dose cohort (MAD), with dose ranges of 10-80 µg and 20-40 µg, respectively. PA9159 was administered bilaterally via nasal spray once only or once daily for seven days. Pharmacokinetic, safety, and tolerability profiles were evaluated. RESULTS: A total of 60 participants completed the study. PA9159 doses of up to 80 µg in the SAD and up to 40 µg in the MAD were shown to be safe and tolerable. The most common treatment-related AEs were mild and transient local nasal AEs. Morning serum cortisol levels approximately remained unchanged in both the single-dose and multiple-dose groups. PA9159 was quantified in 41.8% (368/880) of the samples in all treatment groups, including 25.2% (105/416) of the SAD and 56.7% (263/464) of the MAD. The majority (>80.0%) of PA9159 plasma concentrations ranged from 0.5 to 2 pg/mL in determined samples. The mean AUC0-t of PA9159 in the SAD was 0.91, 1.39±0.68, 11.40±9.91, and 46.30±25.80 h*pg/mL in the 10 to 80 ug single group. The mean terminal half-life time (t1/2) was 8.43 h and 8.97±2.28 h in 40 ug and 80 ug single group, respectively. The mean AUCss of PA9159 in the MAD was 31.70±7.04, 44.20±20.60 h*pg /mL, and the t1/2 was 16.00±4.18 h, 21.20±10.20 h in the 20 ug and 40 ug multiple groups, respectively. The median Tmax was approximately 6 hours in both the SAD and MAD cohorts. CONCLUSIONS: The PA9159 nasal spray was generally safe and well tolerated, and the effects of PA9159 on serum cortisol levels were limited. The plasma concentration and systemic exposure to PA9159 were very low. These findings support the necessity for further clinical studies on PA9159 nasal spray in patients suffering from allergic rhinitis.

High stretchable and tough xylan-g-gelatin hydrogel via the synergy of chemical cross-linking and salting out for strain sensors.

Stretchable and tough hydrogels have been extensively used in tissue engineering scaffolds and flexible electronics. However, it is still a significant challenge to prepare hydrogels with both tensile strength and toughness by utilizing xylan, which is abundant in nature. Herein, we present a novel hydrogel of carboxymethyl xylan(CMX) graft gelatin (G) and doped with conductive hydroxyl carbon nanotubes (OCNT). CMX and G are combined through amide bonding as well as intermolecular hydrogen bonding to form a semi-interpenetrating hydrogel network. The hydrogel was further subjected to salting-out treatment, which induced the aggregation of the CMX-g-G molecular chain and the formation of chain bundles to toughen the hydrogel, the tensile strain, tensile stress, and toughness of CMX-g-G hydrogels were 1.547 MPa, 324 %, and 2.31 MJ m-3, respectively. In addition, OCNT was used as a conductive filler to impart electrical conductivity and further improve the mechanical properties of CMX-g-G/OCNT hydrogel, and a tensile strength of 1.62 MPa was obtained. Thus, the synthesized CMX-g-G/OCNT hydrogel can be used as a reliable and sensitive strain sensor for monitoring human activity. This study opens up new horizons for the preparation of xylan-based high-performance hydrogels.

A Bioequivalence Study With Pharmacokinetic Endpoints for Azithromycin Eye Drops.

Azithromycin eye drops with a bioadhesive ocular drug-delivery system can offer a simplified dosing regimen. In this study, we compared the pharmacokinetic properties and assessed the bioequivalence of a newly developed generic azithromycin eye drop with a branded formulation. This open-label, single-dose, randomized, crossover, sparse-sampling ocular bioequivalence study was conducted on 48 healthy Chinese volunteers. Tear samples were collected for up to 36 hours, and each participant was randomly allocated to one of the prespecified sampling times. Tear drug concentrations were determined using a validated liquid chromatography-tandem mass spectrometry method. The pharmacokinetic parameters were calculated via noncompartmental analysis. A nonparametric bootstrap method was used to obtain 90% confidence intervals (CIs) for the ratios of the test and reference drugs. Tolerability was evaluated for adverse events (AEs). After bootstrapping (1000 iterations), the 90%CIs for the log-transformed ratios of Cmax , AUC0-t , and AUC0-∞ were within the acceptable bioequivalence range (80%-125%). No moderate-to-severe AEs were reported for either formulation. Bioequivalence was demonstrated between the two formulations. The sparse-sampling design with the bootstrapping technique is promising for bioequivalence studies of topical ophthalmic drugs.

Vitamin D receptor gene polymorphisms are associated with the risk and features of myasthenia gravis in the Han Chinese population.

Vitamin D receptor gene (VDR) polymorphisms are candidate genetic variants for susceptibility to autoimmune diseases. Here, we explored the association between VDR polymorphisms and myasthenia gravis (MG) susceptibility and disease features in a Han Chinese population. A total of 151 patients with MG and 146 healthy controls were genotyped for VDR rs1544410, rs2228570, rs731236, and rs7975232 polymorphisms using the improved multiple ligase detection reaction. Information regarding age at onset, acetylcholine receptor (AChR-Ab) and muscle-specific kinase (MuSK-Ab) antibody status, thymus status, involved muscles at onset, and Osserman type at maximum worsening during 2-year follow-up was obtained and used for subclassification grouping. Intergroup comparisons of allele and genotype frequencies and haplotype distributions were performed between the MG and control groups and between each pair of MG subgroups. The VDR rs7975232 polymorphism was associated with the risk of MG in allele, codominant (CC vs. CA), and dominant models (p = 0.040, p = 0.018, and p = 0.018, respectively). Moreover, subjects with the ACC haplotype (order of rs731236, rs7975232, rs1544410) were more likely to develop MG than those with other haplotypes (OR = 1.486, 95% CI: 1.017-2.171, p = 0.040). In a dominant model, the rs7975232 CC genotype frequency was significantly higher in the ocular MG group than in the generalized MG group (p = 0.019). The study findings suggest that the VDR rs7975232 C allele and the ACC haplotype can be associated to an increased susceptibility to the development of MG. Trial registration: NCT05380128.

Bioequivalence of Two Linezolid Tablets Under Fed and Fasting Conditions in Healthy Chinese Individuals.

Linezolid, an oxazolidinone antibacterial agent with several formulations, has been widely used for over 20 years. This study aimed to compare the bioequivalence, pharmacokinetics, and safety of test and reference linezolid tablets after a single oral dose under fasting/fed conditions. In this open-label, randomized, two-period, crossover, bioequivalence study, 48 healthy volunteers were enrolled equally to fasting or fed groups to receive one 600-mg test or reference linezolid tablet in each period. Pharmacokinetic parameters were calculated using noncompartmental methods. Adverse events (AEs) were recorded to assess safety. The geometric mean terminal half-lives of test and reference formulations were 3.8 and 3.6 hours, respectively, under both fasting and fed conditions. The median time to reach the maximum observed concentration was 1.0 hour (both formulations) in the fasting group, and 2.0 hours (test formulation) and 2.5 hours (reference formulation) in the fed group. No substantial differences were observed in the area under plasma concentration-time curve (AUC) from time 0 to the last sampling time (AUC0-t ) and the maximum observed concentration (Cmax ) between formulations. Geometric least square mean ratios for Cmax , AUC0-t , and AUC from time 0 to infinity were approximately 100%, and the corresponding 90% confidence intervals for bioequivalence were within 80%-125%. Ten participants reported 11 AEs; AEs were mild, except for one pregnancy event with an outcome of induced absorption. Bioequivalence between the two linezolid formulations was demonstrated under fasting and fed conditions, and a similar safety profile was observed among healthy Chinese volunteers.

Pharmacokinetics and Bioequivalence of Misoprostol Tablets: An Open-Label, Randomized, Single-dose, Crossover Study With Healthy Chinese Volunteers.

Misoprostol is a synthetic prostaglandin E1 derivative that has been used to treat duodenal and gastric ulcers, and to prevent ulcers caused by nonsteroidal anti-inflammatory drugs in many countries. Misoprostol can also be used for medical abortion. This study aimed to investigate the pharmacokinetic profiles of misoprostol tablets (test product) by comparing them with Cytotec (200 µg) (reference product). To assess the bioequivalence between test and reference products, a two-sequence, two-period crossover study was conducted with 48 healthy Chinese subjects enrolled under fasting conditions. A validated liquid chromatography-tandem mass spectrometry (LC-MS/MS) assay was used to determine the concentration of misoprostol acid in plasma. A mixed model analysis of variance was used to calculate the bioequivalence of pharmacokinetic (PK) parameters. The point estimate of geometric mean ratios with 90% confidence intervals for the maximum observed concentration (Cmax ) and the area under the concentration-time curve (AUC0-t ) for misoprostol acid in reference and test products were 107.8% and 106.5%, respectively (range 80%-125%). Additionally, none of the secondary PK parameters presented significant differences. No severe or more than moderate adverse events were detected in the 48 subjects. However, one subject discontinued the treatment due to drug-related gastrointestinal reactions. All adverse events were mild with rates of 19.2% and 22.9% after the administration test and reference products, respectively. Overall, the bioequivalence between the two misoprostol products was demonstrated in fasting conditions, and all subjects tolerated both treatments.

ABCB1 gene polymorphisms impact the effect of high-dose intravenous methylprednisolone therapy on optic neuritis associated with AQP4-IgG-positive neuromyelitis optica spectrum disorder.

WHAT IS KNOWN AND OBJECTIVE: Patients with optic neuritis (ON) have significant individual differences in their response to high-dose intravenous methylprednisolone (HIMP) therapy. This study aims to evaluate the association between gene polymorphisms and the efficacy of HIMP therapy in Chinese Han patients with ON mediated by aquaporin-4 immunoglobulin G antibody (AQP4-IgG) -positive neuromyelitis optica spectrum disorder (NMOSD) or multiple sclerosis (MS). METHODS: Chinese Han patients with AQP4-IgG+ NMOSD-ON or MS-ON were genotyped for four candidate genes: ABCB1 (rs1045642, rs1128503, rs2032582), NR3C1 (rs41423247), TBX21 (rs9910408, rs16947078) and VDR (rs731236, rs1544410, rs7975232, rs2228570). Patients were divided into glucocorticoid resistance (GR) and glucocorticoid sensitivity (GS) groups based on vision acuity (VA) improvement after HIMP treatment. Intergroup comparisons were performed on clinical characteristics, allele and genotype frequencies and haplotype distributions. RESULTS: A total of 267 patients completed the follow-up, including 120 patients with AQP4-IgG+ NMOSD-ON and 147 patients with MS-ON. We observed a significant association between the ABCB1 G2677T/A (rs2032582) polymorphism and glucocorticoid response in AQP4-IgG+ NMOSD-ON patients. Changes in VA scores in patients with the GG genotype were significantly lower than those in patients with the T/A T/A genotype (1.07 ± 1.20 vs. 1.77 ± 1.31, p = 0.026). In the GS group, the G allele had a lower frequency than the T/A allele (32.03% vs. 60.16%, p = 0.001). Logistic regression analysis showed that the G2677T/A GG and G T/A genotypes could increase the GR risk 3.53 and 2.67 times compared with the T/A T/A genotype, respectively (OR = 3.534, 95% CI: 1.186-10.527, p = 0.023; OR = 2.675, 95% CI: 1.005-7.123, p = 0.049). In addition, haplotype analysis showed that AQP4-IgG+ NMOSD-ON patients with the TAT/TTT haplotype (ABCB1 C3435T-G2677T/A-C1236T) were only 0.54 times more likely to develop GR than those with other haplotypes (OR = 0.542, 95% CI: 0.315-0.932, p = 0.026). However, we did not observe intergroup differences in the MS-ON population. WHAT IS NEW AND CONCLUSION: Our findings suggest that the G > T/A polymorphism of ABCB1 G2677T/A and the TAT/TTT haplotype played a protective role in HIMP treatment of AQP4-IgG+ NMOSD-ON but not MS-ON.

A LC-MS/MS validated method for determination of azithromycin in human tears and its application to an ocular pharmacokinetic study.

A rapid and sensitive method for the quantitative analysis of azithromycin in human tears by LC-MS/MS was developed and validated. Following extraction from collected Schirmer tear strips by methanol-water (4:1, v/v), the analyte and IS (azithromycin-d3) were separated on a Waters Atlantis™ dC18 column (2.1 mm × 30 mm, 3 µm) by gradient elution with 0.1% (v/v) formic acid in methanol-water (1:9) and methanol-acetonitrile (9:1) as the mobile phase. Electrospray ionization in positive ion mode and MRM were used to monitor the ion transitions at m/z 749.6 → 591.6 (azithromycin) and 752.4 → 594.4 (azithromycin-d3). The results indicated that the method had excellent sensitivity and specificity. The analyte appeared to have good linearity in the range of 5-1000 ng/ mL. Both the intra-batch and inter-batch precisions (in terms of RSD) were <10%, and the accuracies (in terms of RE) were within ±15%. The lower limit of quantification, matrix effect, extraction recovery, stability and dilution integrity were also evaluated and satisfied the validation criteria. Artificial tears served as the surrogate matrix, and no matrix difference was found when compared with that of real human tears. Finally, this method was successfully applied in an ocular pharmacokinetic study in healthy volunteers following instillation of azithromycin eyedrops.

Influence of CYP2D6*5 and *10 polymorphism on the pharmacokinetics of nebivolol in healthy Chinese subjects.

WHAT IS KNOWN AND OBJECTIVE: Nebivolol, a selective ß1 adrenoreceptor antagonist, is predominantly metabolized by cytochrome P450 (CYP)2D6 and shows a wide interindividual variability in pharmacokinetics. The present study was conducted to evaluate the effects of the major CYP2D6 polymorphisms on nebivolol disposition in healthy Chinese volunteers. METHODS: Twenty-eight volunteers were enrolled and classified as CYP2D6*1/*1, CYP2D6*1/*10, CYP2D6*10/*10 and CYP2D6*5 carriers according to their genotypes. The concentration of nebivolol was determined by high-performance liquid chromatography-tandem mass spectrometry. The association between the pharmacokinetic parameters and genotypes was evaluated using the unpaired t test or analysis of variance. RESULTS AND DISCUSSION: We evaluated the effects of CYP2D6*5 and *10 polymorphism on the pharmacokinetics of nebivolol. Plasma nebivolol peak concentration and area under the curve (AUC(0-48 h) and AUC(0-∞) ) were significantly higher in subjects with CYP2D6*5 and CYP2D6*10/*10 polymorphism than those in subjects with wild-type CYP2D6 (CYP2D6*1/*1), whereas its plasma clearance was significantly lower in the CYP2D6*10/*10 and CYP2D6*5 carriers. No significant differences in the peak time and terminal half-life of nebivolol were observed among CYP2D6*10/*10, CYP2D6*1/*1 and CYP2D6*5 carriers. WHAT IS NEW AND CONCLUSION: Both CYP2D6*5 and *10 polymorphism altered the pharmacokinetics of nebivolol in healthy Chinese volunteers. Further studies are required to investigate the effects of these single-nucleotide polymorphisms on the pharmacokinetics, pharmacodynamics and toxicity of nebivolol.

Stem cells from human exfoliated deciduous teeth correct the immune imbalance of allergic rhinitis via Treg cells in vivo and in vitro.

BACKGROUND: Several studies have demonstrated that mesenchymal stem cells can ameliorate the inflammation of allergic rhinitis (AR) and correct the Th1/Th2 immune imbalance. METHODS: This study was performed to explore the immunomodulation properties of stem cells from human exfoliated deciduous teeth (SHEDs) in the treatment of AR in vivo and in vitro. BALB/c mice were sensitized to ovalbumin (OVA) by intraperitoneal injection, and then SHEDs or bone marrow mesenchymal stem cells (BMMSCs) were injected intravenously before challenge. We evaluated nasal symptoms, inflammatory infiltration of nasal mucosa, immunoglobulin secretion, cytokine production, and mRNA expression in the spleen. In addition, peripheral blood mononuclear cells (PBMCs) from AR patients were cultured with SHEDs or BMMSCs in the presence of phytohemagglutinin (PHA). PBMCs cultured alone with or without PHA served as controls. After 3 days of culture, we examined the effect of SHEDs on T lymphocyte proliferation, cytokine secretion, and the proportion of Foxp3+ Treg cells via flow cytometry. Finally, to determine the role of soluble factors (TGF-ß1, PGE2) in the immunomodulatory mechanism, a cytokine neutralization assay was performed. RESULTS: Nasal symptoms and inflammatory infiltration were significantly reduced after SHED administration. The OVA-specific IgE and IgG1 levels in serum were significantly decreased, and the increased IL-4, IL-5, IL-13, and IL-17A levels in the spleen after OVA challenge were markedly downregulated, while the level of IFN-γ was upregulated by SHED administration. The mRNA expression levels also changed correspondingly. SHEDs significantly inhibited the proliferation of T lymphocytes; increased the levels of IFN-γ, IL-10, PGE2, and TGF-ß1; decreased the levels of IL-4 and IL-17A; and induced the expansion of Treg cells in the coculture system. The neutralization of TGF-ß1 partly relieved the immunosuppression of SHEDs, but blocking PGE2 did not. In addition, SHEDs were superior to BMMSCs in inhibiting the Th2 immune response in vivo and inducing the expansion of Treg cells in vitro. CONCLUSION: These results suggest that SHEDs could correct the CD4+ T cell immune imbalance via Treg cells and may be potential therapeutic agents for the treatment of allergic diseases, such as AR, in the future.

Glucocorticoid-Induced Transcription Factor 1 (GLCCI1) Variant Impacts the Short-Term Response to Intranasal Corticosteroids in Chinese Han Patients with Seasonal Allergic Rhinitis.

BACKGROUND Genetic correlations with the response to intranasal corticosteroids (INCS) in seasonal allergic rhinitis (SAR) treatment are unknown. This study aimed to evaluate the role of gene polymorphisms in the response to INCS in Chinese Han patients with moderate to severe SAR. MATERIAL AND METHODS In this study, 286 Chinese Han patients with SAR were genotyped for 4 candidate genes: the glucocorticosteroid receptor (NR3C1) gene, glucocorticoid-induced transcription factor 1 (GLCCI1) gene, T-box 21 gene (TBX21), and ATP binding cassette subfamily B member 1 (ABCB1) gene. Patients were treated with INCS for 4 weeks. The total nasal symptom score (TNSS), total ocular symptom score (TOSS), and visual analogue scale (VAS) score were assessed at baseline and on week 4. The primary endpoint was the effective rate after 4 weeks of INCS therapy. RESULTS In addition to the known contributing factors, one genotype of GLCCI1, namely, rs37973, was significantly associated with the INCS response (OR=0.598, 95% confidence interval: 0.41 to 0.87, P=0.007). The effective rate of the GG group was lower than those of the AA and AG groups (AA vs. GG: 73.7% vs. 51.6%, P=0.007; AG vs. GG: 78.8% vs. 51.6%, P=0.000). In addition, the TNSS, TOSS, and VAS were higher for the patients in the GG group than for those in the AA and AG groups on week 4. CONCLUSIONS The GLCCI1 rs37973 variant is a risk factor for glucocorticoid resistance in Chinese patients with SAR who receive short-term INCS treatment.

19-[(1'S,4'R)-4'-Hydroxy-1'-methoxy-2'-oxopentyl]geldanamycin, a natural geldanamycin analogue from Streptomyces hygroscopicus 17997.

A novel natural geldanamycin analogue was discovered in Streptomyces hygroscopicus 17997. Its 4,5-dihydro form was also identified in the gdmP gene disruption mutant of Streptomyces hygroscopicus 17997. The structures of the two compounds were determined to be 19-[(1'S,4'R)-4'-hydroxy-1'-methoxy-2'-oxopentyl]geldanamycin (1) and 19-[(1'S,4'R)-4'-hydroxy-1'-methoxy-2'-oxopentyl]-4,5-dihydrogeldanamycin (2), respectively, by extensive spectroscopic data analysis, including 2D NMR, modified Mosher's method, and electronic circular dichroism. Compared to geldanamycin, 1 and 2 showed increased water solubility and decreased cytotoxicity against HepG2 cells.

Identification of 4,5-dihydro-4-hydroxygeldanamycins as shunt products of geldanamycin biosynthesis.

Two new geldanamycin (GDM) analogues, (4S)-4,5-dihydro-4-hydroxygeldanamycin (1) and (4R)-4,5-dihydro-4-hydroxygeldanamycin (2), were identified from Streptomyces hygroscopicus 17997. Compounds 1 and 2 were not normal intermediates of GDM biosynthesis but shunt products of C-4,5 oxidation catalyzed by GdmP, a cytochrome P450 oxidase acting as a desaturase in GDM biosynthesis. Preliminary assays implied that, compared with GDM, 1 and 2 exhibited decreased cytotoxicity.

Novel 4,5-dihydro-thiazinogeldanamycin in a gdmP mutant strain of Streptomyces hygroscopicus 17997.

Novel geldanamycin derivative, 4,5-dihydro-thiazinogeldanamycin (3), was characterized from the gdmP mutant in Streptomyces hygroscopicus 17997, besides expected 4,5-dihydro-geldanamycin (2). The presence of this compound would suggest an unknown post-PKS modification in geldanamycin biosynthesis. Compound 3 exhibited moderate anti-HSV-1-virus activity and higher water solubility than geldanamycin (1). Cysteine served as a precursor to synthesize 3, whose formation required obligatory enzymatic assistance.

Thiazinogeldanamycin, a new geldanamycin derivative produced by Streptomyces hygroscopicus 17997.

A new geldanamycin (GDM) derivative was discovered and isolated from the fermentation broth of Streptomyces hygroscopicus 17997. Its chemical structure was elucidated as thiazinogeldanamycin by LC-MS, sulfur analysis, and NMR. The addition of cysteine to the fermentation medium significantly stimulated the production level of thiazinogeldanamycin, suggesting cysteine as a precursor of thiazinogeldanamycin production. Although showing a decreased cytotoxicity against HepG2 cancer cells, thiazinogeldanamycin exhibited an improved water solubility and photostability. Thiazinogeldanamycin may represent the first natural GDM derivative characterized so far that uses GDM as its precursor. Its appearance also clearly indicates that an appropriate end-point of fermentation is of critical importance for the maximal production of GDM by Streptomyces hygroscopicus 17997.