Unleashing an Underlying Serious Cardiac Arrhythmia: A Case of Coronary Vasospasm With Atypical Presentation.

This case report highlights the atypical presentation of coronary artery vasospasm in a 59-year-old patient presenting with syncope due to ventricular arrhythmia. Despite initially elevated troponin levels and non-significant lesions observed during left heart catheterization, the patient experienced recurrent chest pain and dizziness, prompting further evaluation. Ultimately, coronary vasospasm was identified as the likely differential diagnosis, supported by various diagnostic modalities including electrocardiogram, Zio patch monitoring, transthoracic echocardiogram, cardiac MRI, and CT angiography. Management involved the initiation of calcium channel blocker therapy, leading to a non-eventful follow-up in the cardiology clinic.

Folate-mediated transport of nanoparticles across the placenta.

BACKGROUND: In this study, a prototype of a targeted nanocarrier for drug delivery for prenatal therapy of the developing fetus was developed and examined in vitro and ex vivo. The folate transport mechanism in the human placenta was utilized as a possible pathway for the transplacental delivery of targeted nanoparticles. METHODS: Several types of folic acid-decorated polymeric nanoparticles were synthesized and characterized. During transport studies of targeted and non-targeted fluorescent nanoparticles across the placental barrier, the apparent permeability values, uptake, transfer indices, and distribution in placental tissue were determined. RESULTS: The nanoparticles had no effect on BeWo b30 cell viability. In vitro, studies showed significantly higher apparent permeability of the targeted nanoparticles across the cell monolayers as compared to the nontargeted nanoparticles (Pe = 5.92 ± 1.44 ×10-6 cm/s for PLGA-PEG-FA vs. 1.26 ± 0.31 ×10-6 cm/s for PLGA-PEG, P < 0.05), and the transport of the targeted nanoparticles was significantly inhibited by excess folate. Ex vivo placental perfusion showed significantly greater accumulation of the targeted nanoparticles in the placental tissue (4.31 ± 0.91%/g for PLGA-PEG-FA vs. 2.07 ± 0.26%/g for PLGA-PEG). CONCLUSION: The data obtained suggested different mechanisms for the uptake and transplacental transfer of targeted versus nontargeted nanoparticles. This targeted nanoformulation may be a promising strategy for fetal drug therapy.

FDA approved drugs with antiviral activity against SARS-CoV-2: From structure-based repurposing to host-specific mechanisms.

The continuing heavy toll of the COVID-19 pandemic necessitates development of therapeutic options. We adopted structure-based drug repurposing to screen FDA-approved drugs for inhibitory effects against main protease enzyme (Mpro) substrate-binding pocket of SARS-CoV-2 for non-covalent and covalent binding. Top candidates were screened against infectious SARS-CoV-2 in a cell-based viral replication assay. Promising candidates included atovaquone, mebendazole, ouabain, dronedarone, and entacapone, although atovaquone and mebendazole were the only two candidates with IC50s that fall within their therapeutic plasma concentration. Additionally, we performed Mpro assays on the top hits, which demonstrated inhibition of Mpro by dronedarone (IC50 18 µM), mebendazole (IC50 19 µM) and entacapone (IC50 9 µM). Atovaquone showed only modest Mpro inhibition, and thus we explored other potential mechanisms. Although atovaquone is Dihydroorotate dehydrogenase (DHODH) inhibitor, we did not observe inhibition of DHODH at the respective SARS-CoV-2 IC50. Metabolomic profiling of atovaquone treated cells showed dysregulation of purine metabolism pathway metabolite, where ecto-5'-nucleotidase (NT5E) was downregulated by atovaquone at concentrations equivalent to its antiviral IC50. Atovaquone and mebendazole are promising candidates with SARS-CoV-2 antiviral activity. While mebendazole does appear to target Mpro, atovaquone may inhibit SARS-CoV-2 viral replication by targeting host purine metabolism.

Effect of deuteration on the single dose pharmacokinetic properties and postoperative analgesic activity of methadone.

Although methadone is effective in the management of acute pain, the complexity of its absorption-distribution-metabolism-excretion profile limits its use as an opioid of choice for perioperative analgesia. Because deuteration is known to improve the pharmacokinetic, pharmacodynamic and toxicological properties of some drugs, here we characterized the single dose pharmacokinetic properties and post-operative analgesic efficacy of d9-methadone. The pharmacokinetic profiles of d9-methadone and methadone administered intravenously to CD-1 male mice revealed that deuteration leads to a 5.7- and 4.4-fold increase in the area under the time-concentration curve and maximum concentration in plasma, respectively, as well as reduction in clearance (0.9 ± 0.3 L/h/kg vs 4.7 ± 0.8 L/h/kg). The lower brain-to-plasma ratio of d9-methadone compared to that of methadone (0.35 ± 0.12 vs 2.05 ± 0.62) suggested that deuteration decreases the transfer of the drug across the blood-brain barrier. The estimated LD50 value for a single intravenous dose of d9-methadone was 2.1-fold higher than that for methadone. Moreover, d9-methadone outperformed methadone in the efficacy against postoperative pain by primarily activating peripheral opioid receptors. Collectively, these data suggest that the replacement of three hydrogen atoms in three methyl groups of methadone altered its pharmacokinetic properties, improved safety, and enhanced its analgesic efficacy.

Atovaquone for treatment of COVID-19: A prospective randomized, double-blind, placebo-controlled clinical trial.

Background: An in silico screen was performed to identify FDA approved drugs that inhibit SARS-CoV-2 main protease (Mpro), followed by in vitro viral replication assays, and in vivo pharmacokinetic studies in mice. These studies identified atovaquone as a promising candidate for inhibiting viral replication. Methods: A 2-center, randomized, double-blind, placebo-controlled trial was performed among patients hospitalized with COVID-19 infection. Enrolled patients were randomized 2:1 to atovaquone 1500 mg BID versus matched placebo. Patients received standard of care treatment including remdesivir, dexamethasone, or convalescent plasma as deemed necessary by the treating team. Saliva was collected at baseline and twice per day for up to 10 days for RNA extraction for SARS-CoV-2 viral load measurement by quantitative reverse-transcriptase PCR. The primary outcome was the between group difference in log-transformed viral load (copies/mL) using a generalized linear mixed-effect models of repeated measures from all samples. Results: Of the 61 patients enrolled; 41 received atovaquone and 19 received placebo. Overall, the population was predominately male (63%) and Hispanic (70%), with a mean age of 51 years, enrolled a mean of 5 days from symptom onset. The log10 viral load was 5.25 copies/mL vs. 4.79 copies/mL at baseline in the atovaquone vs. placebo group. Change in viral load did not differ over time between the atovaquone plus standard of care arm versus the placebo plus standard of care arm. Pharmacokinetic (PK) studies of atovaquone plasma concentration demonstrated a wide variation in atovaquone levels, with an inverse correlation between BMI and atovaquone levels, (Rho -0.45, p = 0.02). In post hoc analysis, an inverse correlation was observed between atovaquone levels and viral load (Rho -0.54, p = 0.005). Conclusion: In this prospective, randomized, placebo-controlled trial, atovaquone did not demonstrate evidence of enhanced SARS-CoV-2 viral clearance compared with placebo. However, based on the observed inverse correlation between atovaquone levels and viral load, additional PK-guided studies may be warranted to examine the antiviral effect of atovaquone in COVID-19 patients.

Ex vivo dual perfusion of an isolated human placenta cotyledon: Towards protocol standardization and improved inter-centre comparability.

Since the full development of the ex vivo dual perfusion model of the human placenta cotyledon, the technique has provided essential insight into how nutrients, lipids, gases, immunoglobulins, endocrine agents, pharmaceuticals, chemicals, nanoparticles, micro-organisms and parasites might traverse the maternofetal barrier. Additionally, the model has been instrumental in gaining a better understanding of the regulation of vascular tone, endocrinology and metabolism within this organ. The human placenta is unique amongst species in its anatomy and transfer modalities. This orthologous diversity therefore requires an appropriate consideration of placental transfer rates of compounds, particles and micro-organisms specific to humans. Different research centres have adapted this model with a wide variation in perfusion parameters, including in the establishment of perfusion, perfusate composition, gassing regime, cannulation method, flow rates, perfused tissue mass, and also in the application of quality control measures. The requirement to harmonise and standardise perfusion practice between centres is largely driven by the need to obtain consistency in our understanding of placental function, but also in the qualification of the model for acceptance by regulatory agencies in drug and toxicology testing. A pilot study is proposed, aiming to describe how existing inter-centre variation in perfusion methodology affects placental metabolism, protein synthesis, oxygen consumption, the materno-fetal transfer of key molecular markers, and placental structure.

Physicochemical and Biological Properties of Membrane Vesicles Derived from Human Term Placentas.

The purpose of this study was to conduct initial characterization of membrane vesicles isolated from human placenta by agitation of villous tissue (apical and basal) as well as vesicles obtained following dual perfusion of placental lobule. The morphology, physical and biological properties of the isolated vesicles were determined by electron microscopy, dynamic light scattering, and immunoblotting as well as nanoflow liquid chromatography-mass spectrometry proteomics analysis. CD-1 male mice were used to test the biocompatibility of the vesicles in vivo and assess the biodistribution of fluorescently labeled apical and perfusion vesicles. The vesicles obtained following placental perfusion and the apical vesicles had Z-average diameters of 199±23 nm and 246±24 nm, respectively, and demonstrated nanocarrier stability, low toxicity, and low immunogenicity. On the other hand, administration of basal vesicles resulted in animal demise with LD50 of 0.85 µgprotein/g. Both fluorescently labeled apical and perfusion vesicles were detected in the lungs, liver, kidneys, and spleen of CD-1 mice within 24 h of administration. However, there were differences in organ distribution of these vesicles over 24 hours time period. These data suggest that placental apical and perfusion vesicles have a potential for further development as biological vehicles for drug delivery.

Role of Uptake Transporters OAT4, OATP2A1, and OATP1A2 in Human Placental Bio-disposition of Pravastatin.

Pravastatin is currently under evaluation for prevention of preeclampsia. Factors contributing to placental disposition of pravastatin are important in assessment of potential undesirable fetal effects. The purpose of this study was to identify the uptake transporters that contribute to the placental disposition of pravastatin. Our data revealed the expression of organic anion transporting polypeptide 1A2 (OATP1A2) and OATP2A1 in the apical, and OATP2B1 and OATP5A1 in the basolateral membranes of the placenta, while organic anion transporter 4 (OAT4) exhibited higher expression in basolateral membrane but was detected in both membranes. Preloading placental membrane vesicles with glutarate increased the uptake of pravastatin suggesting involvement of glutarate-dependent transporters such as OAT4. In the HEK293 cells overexpressing individual uptake transporters, OATP2A1, OATP1A2 and OAT4 were determined to accept pravastatin as a substrate at physiological pH, while the uptake of pravastatin by OATP2B1 (known to interact with pravastatin at acidic pH) and OATP5A1 was not detected at pH 7.4. These findings led us to propose that OATP1A2 and OATP2A1 are responsible for the placental uptake of pravastatin from the maternal circulation, while OAT4 mediates the passage of the drug across placental basolateral membrane in the fetal-to-maternal direction.

Prediction of maternal and fetal pharmacokinetics of indomethacin in pregnancy.

AIMS: Indomethacin is used for the treatment of preterm labour, short cervices and idiopathic polyhydramnios during pregnancy. Few studies have described the pharmacokinetics (PK) of indomethacin during pregnancy. This study aimed to determine maternal and fetal PK of indomethacin during different trimesters of pregnancy using physiologically based PK (PBPK) modelling and simulations. METHODS: Full PBPK simulations were performed in nonpregnant subjects and pregnant subjects from each trimester of pregnancy at steady state using Simcyp's healthy volunteers and pregnancy PBPK model, respectively. The fetal exposures were predicted using a fetoplacental pregnancy PBPK model. The models were verified by comparing PBPK-based predictions with observed PK profiles. RESULTS: Predicted exposure (AUC0-6h ) and clearance of indomethacin in nonpregnant women and pregnant women are similar to the clinical observations. AUC0-6h of indomethacin is approximately 14, 24 and 32% lower, consistent with 18, 34 and 52% higher clearance in the first, second and third trimesters of pregnancy, respectively, compared to nonpregnant women. Predicted fetal plasma exposures increased by approximately 30% from the second trimester to the third trimester of pregnancy. CONCLUSION: A mechanistic PBPK model adequately described the maternal and the fetal PK of indomethacin during pregnancy. As the pregnancy progresses, a modest decrease (≤32%) in systemic exposures in pregnant women and a 33% increase in fetal exposures to indomethacin were predicted. Higher fetal exposures in the third trimester of pregnancy may pose safety risks to the fetus. Additional studies are warranted to understand the exposure-response relationship and provide appropriate dosing recommendations during pregnancy that consider both safety and efficacy.

Nanomolar potency of imidazo[2,1-b]thiazole analogs as indoleamine 2,3-dioxygenase inhibitors.

Novel series of imidazo[2,1-b]thiazole analogs were designed, synthesized, and biologically evaluated as indoleamine 2,3-dioxygenase (IDO1) inhibitors. Imidazo[2,1-b]thiazoles 6, 7, and 8 showed inhibitory profiles against IDO1 at IC50 values of 68.48, 82.39, and 48.48 nM, respectively, compared with IDO5L at IC50 67.40 nM. Benzo[d]imidazo[2,1-b]thiazoles 17, 20, and 22 showed promising IDO1 inhibition at IC50 values of 53.58, 53.16, and 57.95 nM, respectively. Compound 7 showed a growth-inhibitory profile at GI of 39.33% against the MCF7 breast cancer cell line, while 8 proved lethal to ACHN renal cancer cells. Cells treated with compounds 17 and 22 showed a typical apoptosis pattern of DNA fragments that reflected the G0/G1, S, and G2/M phases of the cell cycle, together with a pre-G1 phase corresponding to apoptotic cells, which indicates that cell growth arrest occurred at the S phase. Molecular modeling simulations validated the potential of benzo[d]imidazo[2,1-b]thiazole analogs to chelate iron(III) within the IDO1 binding pocket and, hence, to have a better binding affinity via hydrophobic-hydrophobic interactions.

3-Methyl-imidazo[2,1-b]thiazole derivatives as a new class of antifolates: Synthesis, in vitro/in vivo bio-evaluation and molecular modeling simulations.

Inhibiting the Dihydrofolate reductase (DHFR) enzyme has been validated in multiple clinical manifestations related to bacterial infection, malaria, and multiple types of cancer. Herein, novel series of 3-methyl-imidazo[2,1-b] thiazole-based analogs were synthesized and biologically evaluated for their in vitro inhibitory profile towards DHFR. Compounds 22 and 23 exhibited potent inhibitory profile targeting DHFR (IC50 0.079 and 0.085 µM, respectively comparable to MTX IC50 0.087 µM). Compounds 22 and 23 showed promising cytotoxicity against MCF7 breast cancer cell lines inducing cell cycle arrest and apoptosis. Furthermore, Compound 23 showed its potential to reduce body weight and tumor volume significantly, using Ehrlich ascites carcinoma (EAC) solid tumor animal model of breast cancer, compared to control-treated groups. Further, molecular modeling simulations validated the potential of 22 and 23 to have high affinity binding towards Arg22 and Phe31 residues via π-π interaction and hydrogen bonding within DHFR binding pocket. Computer-assisted ADMET study suggested that the newly synthesized analogs could have high penetration to the blood brain barrier (BBB), better intestinal absorption, non-inhibitors of CYP2D6, adequate plasma protein binding and good passive oral absorption. The obtained model and pattern of substitution could be used for further development of DHFR inhibitors.

A randomized pilot clinical trial of pravastatin versus placebo in pregnant patients at high risk of preeclampsia.

BACKGROUND: Preeclampsia remains a major cause of maternal and neonatal morbidity and mortality. Biologic plausibility, compelling preliminary data, and a pilot clinical trial support the safety and utility of pravastatin for the prevention of preeclampsia. OBJECTIVE: We previously reported the results of a phase I clinical trial using a low dose (10 mg) of pravastatin in high-risk pregnant women. Here, we report a follow-up, randomized trial of 20 mg pravastatin versus placebo among pregnant women with previous preeclampsia who required delivery before 34+6 weeks' gestation with the objective of evaluating the safety and pharmacokinetic parameters of pravastatin. STUDY DESIGN: This was a pilot, multicenter, blinded, placebo-controlled, randomized trial of women with singleton, nonanomalous pregnancies at high risk for preeclampsia. Women between 12+0 and 16+6 weeks of gestation were assigned to receive a daily pravastatin dose of 20 mg or placebo orally until delivery. In addition, steady-state pravastatin pharmacokinetic studies were conducted in the second and third trimesters of pregnancy and at 4 to 6 months postpartum. Primary outcomes included maternal-fetal safety and pharmacokinetic parameters of pravastatin during pregnancy. Secondary outcomes included maternal and umbilical cord blood chemistries and maternal and neonatal outcomes, including rates of preeclampsia and preterm delivery, gestational age at delivery, and birthweight. RESULTS: Of note, 10 women assigned to receive pravastatin and 10 assigned to receive the placebo completed the trial. No significant differences were observed between the 2 groups in the rates of adverse or serious adverse events, congenital anomalies, or maternal and umbilical cord blood chemistries. Headache followed by heartburn and musculoskeletal pain were the most common side effects. We report the pravastatin pharmacokinetic parameters including pravastatin area under the curve (total drug exposure over a dosing interval), apparent oral clearance, half-life, and others during pregnancy and compare it with those values measured during the postpartum period. In the majority of the umbilical cord and maternal samples at the time of delivery, pravastatin concentrations were below the limit of quantification of the assay. The pregnancy and neonatal outcomes were more favorable in the pravastatin group. All newborns passed their brainstem auditory evoked response potential or similar hearing screening tests. The average maximum concentration and area under the curve values were more than 2-fold higher following a daily 20 mg dose compared with a 10 mg daily pravastatin dose, but the apparent oral clearance, half-life, and time to reach maximum concentration were similar, which is consistent with the previously reported linear, dose-independent pharmacokinetics of pravastatin in nonpregnant subjects. CONCLUSION: This study confirmed the overall safety and favorable pregnancy outcomes for pravastatin in women at high risk for preeclampsia. This favorable risk-benefit analysis justifies a larger clinical trial to evaluate the efficacy of pravastatin for the prevention of preeclampsia. Until then, pravastatin use during pregnancy remains investigational.

Identification of tetracycline combinations as EphB1 tyrosine kinase inhibitors for treatment of neuropathic pain.

Previous studies have demonstrated that the synaptic EphB1 receptor tyrosine kinase is a major mediator of neuropathic pain, suggesting that targeting the activity of this receptor might be a viable therapeutic option. Therefore, we set out to determine if any FDA-approved drugs can act as inhibitors of the EphB1 intracellular catalytic domain. An in silico screen was first used to identify a number of tetracycline antibiotics which demonstrated potential docking to the ATP-binding catalytic domain of EphB1. Kinase assays showed that demeclocycline, chlortetracycline, and minocycline inhibit EphB1 kinase activity at low micromolar concentrations. In addition, we cocrystallized chlortetracycline and EphB1 receptor, which confirmed its binding to the ATP-binding domain. Finally, in vivo administration of the three-tetracycline combination inhibited the phosphorylation of EphB1 in the brain, spinal cord, and dorsal root ganglion (DRG) and effectively blocked neuropathic pain in mice. These results indicate that demeclocycline, chlortetracycline, and minocycline can be repurposed for treatment of neuropathic pain and potentially for other indications that would benefit from inhibition of EphB1 receptor kinase activity.

Formulation effects on paclitaxel transfer and uptake in the human placenta.

Diagnosis and treatment of breast cancer in pregnancy can result in morbidity and mortality for the mother and fetus. Many new paclitaxel nanoformulations commercially available worldwide for breast cancer treatment are being adopted due to favorable dosing regimens and side effect profiles, but their transplacental transport and resultant fetal exposure remain unknown. Here, we examine three formulations: Taxol (paclitaxel dissolved in Kolliphor EL and ethanol); Abraxane (albumin nanoparticle); and Genexol-PM (polymeric micelle). In the ex vivo dually perfused human placental cotyledon, placental accumulation of Genexol-PM is higher than Taxol, and both nanoformulations have lower maternal concentrations of paclitaxel over time. In vitro studies of these formulations and fluorescent nanoparticle analogs demonstrate that Genexol-PM allows paclitaxel to overcome P-glycoprotein efflux, but Abraxane behaves as a free drug formulation. We anticipate that these findings will impact future development of rational and safe treatment strategies for pregnancy-associated breast cancer and other diseases.

Cardiovascular benefits from SGLT2 inhibition in type 2 diabetes mellitus patients is not impaired with phosphate flux related to pharmacotherapy.

The beneficial cardiorenal outcomes of sodium-glucose cotransporter 2 inhibitors (SGLT2i) in patients with type 2 diabetes mellitus (T2DM) have been substantiated by multiple clinical trials, resulting in increased interest in the multifarious pathways by which their mechanisms act. The principal effect of SGLT2i (-flozin drugs) can be appreciated in their ability to block the SGLT2 protein within the kidneys, inhibiting glucose reabsorption, and causing an associated osmotic diuresis. This ameliorates plasma glucose elevations and the negative cardiorenal sequelae associated with the latter. These include aberrant mitochondrial metabolism and oxidative stress burden, endothelial cell dysfunction, pernicious neurohormonal activation, and the development of inimical hemodynamics. Positive outcomes within these domains have been validated with SGLT2i administration. However, by modulating the sodium-glucose cotransporter in the proximal tubule (PT), SGLT2i consequently promotes sodium-phosphate cotransporter activity with phosphate retention. Phosphatemia, even at physiologic levels, poses a risk in cardiovascular disease burden, more so in patients with type 2 diabetes mellitus (T2DM). There also exists an association between phosphatemia and renal impairment, the latter hampering cardiovascular function through an array of physiologic roles, such as fluid regulation, hormonal tone, and neuromodulation. Moreover, increased phosphate flux is associated with an associated increase in fibroblast growth factor 23 levels, also detrimental to homeostatic cardiometabolic function. A contemporary commentary concerning this notion unifying cardiovascular outcome trial data with the translational biology of phosphate is scant within the literature. Given the apparent beneficial outcomes associated with SGLT2i administration notwithstanding negative effects of phosphatemia, we discuss in this review the effects of phosphate on the cardiometabolic status in patients with T2DM and cardiorenal disease, as well as the mechanisms by which SGLT2i counteract or overcome them to achieve their net effects. Content drawn to develop this conversation begins with proceedings in the basic sciences and works towards clinical trial data.

Pharmacodynamics of Glyburide, Metformin, and Glyburide/Metformin Combination Therapy in the Treatment of Gestational Diabetes Mellitus.

In gestational diabetes mellitus (GDM), women are unable to compensate for the increased insulin resistance during pregnancy. Data are limited regarding the pharmacodynamic effects of metformin and glyburide during pregnancy. This study characterized insulin sensitivity (SI), ß-cell responsivity, and disposition index (DI) in women with GDM utilizing a mixed-meal tolerance test (MMTT) before and during treatment with glyburide monotherapy (GLY, n = 38), metformin monotherapy (MET, n = 34), or GLY and MET combination therapy (COMBO; n = 36). GLY significantly decreased dynamic ß-cell responsivity (31%). MET and COMBO significantly increased SI (121% and 83%, respectively). Whereas GLY, MET, and COMBO improved DI, metformin (MET and COMBO) demonstrated a larger increase in DI (P = 0.05) and a larger decrease in MMTT peak glucose concentrations (P = 0.03) than subjects taking only GLY. Maximizing SI with MET followed by increasing ß-cell responsivity with GLY or supplementing with insulin might be a more optimal strategy for GDM management than monotherapy.

Pharmacodynamics of Metformin in Pregnant Women With Gestational Diabetes Mellitus and Nonpregnant Women With Type 2 Diabetes Mellitus.

Gestational diabetes mellitus is a condition similar to type 2 diabetes mellitus (T2DM) in that patients are unable to compensate for the degree of insulin resistance, and both conditions are often treated with metformin. The comparative pharmacodynamic response to metformin in these 2 populations has not been studied. This study characterized insulin sensitivity, ß-cell responsivity, and disposition index following a mixed-meal tolerance test utilizing a minimal model of glucose, insulin, and C-peptide kinetics before and during treatment with metformin. The study included women with gestational diabetes mellitus (n = 34), T2DM (n = 14), and healthy pregnant women (n = 30). Before treatment, the gestational diabetes mellitus group had significantly higher baseline (45%), dynamic (68%), static (71%), and total ß-cell responsivity (71%) than the T2DM group. Metformin significantly increased insulin sensitivity (51%) as well as disposition index (97%) and decreased mixed-meal tolerance test peak glucose concentrations (8%) in women with gestational diabetes mellitus after adjustment for gestational age-dependent effects; however, in women with T2DM metformin only significantly affected peak glucose concentrations (22%) and had no significant effect on any other parameters. Metformin had a greater effect on the change in disposition index (Δ disposition index) in women with gestational diabetes mellitus than in those with T2DM (P = .01). In conclusion, response to metformin in women with gestational diabetes mellitus is significantly different from that in women with T2DM, which is likely related to the differences in disease severity.

Effect of CYP2C9 Polymorphisms on the Pharmacokinetics of Indomethacin During Pregnancy.

BACKGROUND AND OBJECTIVE: Cytochrome P450 (CYP) 2C9 catalyzes the biotransformation of indomethacin to its inactive metabolite O-desmethylindomethacin (DMI). The aim of this work was to determine the effect of CYP2C9 polymorphisms on indomethacin metabolism in pregnant women. METHODS: Plasma concentrations of indomethacin and DMI at steady state were analyzed with a validated LC-MS/MS method. DNA was isolated from subject blood and buccal smear samples. Subjects were grouped by genotype for comparisons of pharmacokinetic parameters. RESULTS: For subjects with the *1/*2 genotype, the mean steady-state apparent oral clearance (CL/Fss) of indomethacin was 13.5 ± 7.7 L/h (n = 4) and the mean metabolic ratio (AUCDMI/AUCindomethacin) was 0.291 ± 0.133. For subjects with the *1/*1 genotype, these values were 12.4 ± 2.7 L/h and 0.221 ± 0.078, respectively (n = 14). Of note, we identified one subject who was a carrier of both the *3 and *4 alleles, resulting in an amino acid change (I359P) which has not been reported previously. This subject had a metabolic ratio of 0.390 and a CL/Fss of indomethacin (24.3 L/h) that was nearly double the wild-type clearance. CONCLUSION: Although our results are limited by sample size and are not statistically significant, these data suggest that certain genetic polymorphisms of CYP2C9 may lead to an increased metabolic ratio and an increase in the clearance of indomethacin. More data are needed to assess the impact of CYP2C9 genotype on the effectiveness of indomethacin as a tocolytic agent.

Neonatal abstinence syndrome.

Neonatal abstinence syndrome refers to the signs and symptoms attributed to the cessation of prenatal exposure (via placental transfer) to various substances. This Primer focuses on neonatal abstinence syndrome caused by opioid use during pregnancy - neonatal opioid withdrawal syndrome (NOWS). As the global prevalence of opioid use has alarmingly increased, so has the incidence of NOWS. NOWS can manifest with varying severity or not at all, for unknown reasons, but is likely to be associated with multiple factors, both maternal (for example, smoking and additional substance exposures) and neonatal (gestational age, sex and genetics). Care for the infant with NOWS begins with addressing the issues experienced by pregnant women with opioid use disorder. Co-occurring mental illness, economic hardship, intimate partner violence, infectious diseases and limited access to care are common in these women and can result in poor maternal and neonatal outcomes. Although there is no consensus regarding optimal NOWS management, non-pharmacological interventions (such as breastfeeding and rooming-in of the mother and the baby) have become a priority, as they can ameliorate symptoms without the need for further opioid exposure. Untreated NOWS can be associated with morbidity in early infancy, and the long-term consequences of fetal opioid exposure are only beginning to be understood.