Post Dose Research Articles

Pharmacokinetics of Atorvastatin and Metformin after Coadministration with Islatravir in Healthy Adults.

Islatravir, a deoxyadenosine analog that inhibits HIV-1 replication by multiple mechanisms of action, including reverse transcriptase translocation inhibition, is being developed for use in HIV-1 treatment. People living with HIV often have comorbidities, such as dyslipidemia or type 2 diabetes mellitus, necessitating long-term concomitant drug therapy. This nonrandomized, two-period, fixed-sequence, open-label, phase 1, drug-drug interaction study was conducted to evaluate the effects of islatravir coadministration on atorvastatin and metformin pharmacokinetics (PK) in healthy adults. In period 1, participants received a single dose of atorvastatin 20 mg and metformin 1000 mg. After a 5-day washout, participants received atorvastatin 20 mg and metformin 1000 mg coadministered with a single oral dose of islatravir 60 mg (period2). In both periods, blood samples were collected up to 72 h post dose to characterize the plasma PK of atorvastatin and metformin. Safety was monitored throughout the study. Fourteen participants were enrolled and completed the study. Atorvastatin and metformin plasma PK were similar after administration of atorvastatin and metformin with or without islatravir. The geometric mean ratio and 90% confidence interval of the area under the concentration-time curve from time zero to infinity (AUC0-∞) for atorvastatin and metformin with or without a single oral dose of islatravir were 1.04 (1.00-1.10) and 0.87 (0.79-0.96), respectively. Coadministration of islatravir with atorvastatin and metformin was well tolerated. Overall, coadministration of atorvastatin and metformin with a single oral dose of islatravir did not have a clinically meaningful effect on the PK profiles of either drug.

Safety and tolerability of ubrogepant for the acute treatment of migraine in participants taking atogepant for the preventive treatment of episodic migraine: Results from the TANDEM study.

To evaluate the safety and tolerability of ubrogepant for the acute treatment of migraine in participants taking atogepant for the preventive treatment of episodic migraine (EM). Atogepant is an oral calcitonin gene-related peptide (CGRP) receptor antagonist approved for the preventive treatment of migraine in adults and ubrogepant is an oral CGRP receptor antagonist approved for the acute treatment of migraine in adults, with or without aura. The safety and tolerability of the concomitant use of ubrogepant and atogepant have not been previously evaluated in a clinical setting. The TANDEM study, a phase 4, two-period, multicenter, open-label study conducted in the United States, enrolled adults with migraine, with or without aura, and <15 headache days/month. In Treatment Period 1, participants took atogepant 60 mg once daily (QD) for 12 weeks and their own non-gepant acute headache medication for breakthrough migraine attacks. In Treatment Period 2, participants continued taking atogepant 60 mg QD and ubrogepant 100 mg was taken as needed (PRN) for the treatment of breakthrough migraine attacks (up to eight per 4-week interval) for 12 weeks. In Treatment Period 2, an optional second ubrogepant dose or the participant's own acute medication could be used to rescue headaches that did not resolve within 2-24 h post initial ubrogepant dose. The primary objective evaluated the safety and tolerability of the concomitant use of ubrogepant and atogepant. Of 263 participants enrolled, 262 were treated in Treatment Period 1 (Safety Population 1) and 218 continued and were treated in Treatment Period 2 (Safety Population 2). The mean (standard deviation) number of ubrogepant use days in Treatment Period 2 was 6.6 (5.03) over the 12 weeks. In Treatment Periods 1 and 2, 49.6% and 43.1% of participants experienced a treatment-emergent adverse event (TEAE), respectively. The most common TEAEs (≥5%) in Treatment Period 1 and Treatment Period 2 were COVID-19 (8.4%, 3.2%), fatigue (6.5%, 1.4%), nausea (6.1%, 0.9%), decreased appetite (5.7%, 0.9%), and constipation (5.3%, 0.9%). In Treatment Period 2, no increase in the incidence and types of TEAEs in relation to the number of ubrogepant use days or doses taken were identified. During the whole treatment period, 9.9% of participants discontinued atogepant or ubrogepant treatment due to TEAEs. There was one serious TEAE in Treatment Period 1 (ureterolithiasis) and one in Treatment Period 2 (cervical myelopathy), and both were considered not related to study treatment by the study investigators. The use of atogepant 60 mg QD for the preventive treatment of EM and ubrogepant 100 mg PRN for the acute treatment of migraine over the 12-week open-label concomitant use treatment period was safe and well tolerated. The overall safety results were consistent with the known safety profiles of atogepant and ubrogepant when used alone and no new safety signals were identified.

Initiation response, maximized therapeutic efficacy, and post-treatment effects of biological targeted therapies in myasthenia gravis: a systematic review and network meta-analysis.

As targeted drug development in myasthenia gravis (MG) continues to advance, it is important to compare the efficacy of these drugs for better clinical decision-making. However, due to the varied regimens and dosages used in clinical trials for different drugs, a standardized comparison between them is necessary. This study enrolled participants in phase II and III trials of innovative targeted drugs for MG. The primary outcome was the change in Quantitative Myasthenia Gravis score (MG-QMG) from baseline. The efficacy of all drugs at four time points was separately analyzed at four time points: initiation 1 week, initiation 4 weeks, maximized response, and post last dose 4 weeks. A network meta-analysis was conducted to compare the results of the different drugs. A total of 9 drugs, including Efgartigimod, Rozanolixizumab, Batoclimab, Eculizumab, Belimumab, Zilucoplan, Ravulizumab, Nipocalimab, Rituximab, derived from 12 studies were analyzed. At the initiation 1-week time point, three drugs exhibited significant improvement compared to the placebo effect: Efgartigimod, Zilucoplan, Rozanolixizumab. At the initiation 4-week time point, four drugs showed significant improvement compared to the placebo effect: Efgartigimod, Rozanolixizumab, Batoclimab, Zilucoplan. At the maximized response time point, six drugs achieved significant improvement compared to the placebo effect: Efgartigimod, Rozanolixizumab, Batoclimab, Eculizumab, Zilucoplan, Ravulizumab. At the post last dose 4-week point, all drugs statistically showed no significant difference from the placebo. Although the MG subtypes were not consistent across trials, within the regimen design of each trial, neonatal Fc receptor inhibitors-represented by Efgartigimod, Rozanolixizumab, and Batoclimab-exhibited the most effective response rates when compared to complement and B-cell inhibitor drugs.

Humoral and cellular immune response to AZD1222 /Covishield and BV152/Covaxin COVID-19 vaccines among adults in India

ABSTRACT Several COVID-19 vaccines were developed using different approaches to prevent both symptomatic COVID-19 cases and fatalities. The adults were vaccinated with two doses of AZD1222/Covishield (n = 77) [manufactured by Serum Institute of India Pvt Ltd] vaccine and BV152/Covaxin (n = 99) [manufactured by Bharat Biotech] vaccine. They were assessed for immune response at pre-vaccination, 1 month post first and 6 months post second dose for anti-SARS-CoV-2 IgG antibody, surrogate neutralizing antibody (NAbs), immune phenotypes, antigen specific NK, B and T cell response, their effector functionality by ELISPOT and plasma cytokine profile. Both vaccines elicited enhanced IgG antibody and Nab levels compared to the baseline. BV152/Covaxin, the whole virus inactivated vaccine exhibited higher IgG (70% vs 100%), Nab (90% vs 100%), and robust T cell (31% vs 96%) responses at 6 months post second dose compared to 1 month post first dose justifying the utility of the second dose. Detection of SARS-CoV-2 WV and S1 specific CD4+ central T cell memory response in AZD1222/Covishield vaccinee at 6 months post second dose and higher CD4+ and CD8+ naïve and central memory T cell response in BV152/Covaxin vaccinee at 1 month post first dose indicated the involvement of memory T cells. Persistent IgG and NAb responses along with IgG+B and IgG+memory B cells in AZD1222/Covishield recipients at 6 months post second dose indicated sustained immune memory response. Continued heightened IFN-γ secreting T cell response (ELISPOT) displayed by both the vaccine platforms could serve as a co correlate of protection, further to evaluation in follow up studies. Overall, our data suggest that coordinated functions of humoral and cellular branches of adaptive immunity may pave ways toward protective immunity against COVID-19.

Rotavirus-Specific Maternal Serum Antibodies and Vaccine Responses to RV3-BB Rotavirus Vaccine Administered in a Neonatal or Infant Schedule in Malawi.

High titres of rotavirus-specific maternal antibodies may contribute to lower rotavirus vaccine efficacy in low- and middle-income countries (LMICs). RV3-BB vaccine (G3P[6]) is based on a neonatal rotavirus strain that replicates well in the newborn gut in the presence of breast milk. This study investigated the association between maternal serum antibodies and vaccine response in infants administered the RV3-BB vaccine. Serum was collected antenatally from mothers of 561 infants enrolled in the RV3-BB Phase II study conducted in Blantyre, Malawi, and analysed for rotavirus-specific serum IgA and IgG antibodies using enzyme-linked immunosorbent assay. Infant vaccine take was defined as cumulative IgA seroconversion (≥3 fold increase) and/or stool vaccine shedding. Maternal IgA or IgG antibody titres did not have a negative impact on vaccine-like stool shedding at any timepoint. Maternal IgG (but not IgA) titres were associated with reduced take post dose 1 (p < 0.005) and 3 (p < 0.05) in the neonatal vaccine schedule group but not at study completion (week 18). In LMICs where high maternal antibodies are associated with low rotavirus vaccine efficacy, RV3-BB in a neonatal or infant vaccine schedule has the potential to provide protection against severe rotavirus disease.

Comparative Pharmacokinetics and Tissue Distribution of Hexahydrocurcumin Following Intraperitoneal vs Oral Administration in Mice Using LC-MS/MS.

A liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was developed and validated to determine hexahydrocurcumin (HHC) levels in mouse plasma, brain, liver, and kidneys using a negative ion mode electrospray ionization (ESI) source. Demonstrating a lower limit of quantification (LLOQ) of 5 ng/mL, the method showed excellent linearity across a concentration range of 5-500 ng/mL in all tested matrices. Precision evaluations reported a coefficient of variation (CV%) of less than 13.19% for both intraday and interday measurements, while accuracy ranged from 95.13 to 105.07% across all quality control levels. HHC extraction recovery was consistently observed between 70.18 and 93.28%, with a CV% deviation of less than 15%. In the pharmacokinetic evaluation of HHC in mice following a single intraperitoneal (IP) or oral administration, a noncompartment analysis was utilized. After IP administration (40 mg/kg), the C max value was 47.90 times higher than that achieved via oral administration. Peak plasma concentrations were observed approximately 5 min post-IP and 15 min post-oral dosing. The observed half-lives after these administrations were approximately 1.52 and 2.17 h for IP and oral routes, respectively. Oral administration revealed a relative bioavailability of only 12.28% compared with the IP route. Furthermore, following IP administration, the half-life values in brain, liver, and kidney were not significantly different but more than the half-life value found in plasma. The liver and kidney exhibited the highest concentrations of HHC, while the brain showed the least, suggesting that the hydrophobic nature of HHC impedes its passage through the blood-brain barrier. This study is the first to provide detailed insights into the pharmacokinetics and tissue distribution characteristics of HHC following oral and IP administration in mice, setting the stage for further focus on HHC as a potential new drug candidate.

362 Nutrikinetic evaluation and modeling of 25-hydroxyvitamin D3 in beef cattle

Abstract The objective of this study was to evaluate serum 25-hydroxyvitamin D3 [25(OH)D3] status in beef cattle when 1) fed diets with supplemental 25(OH)D3 or calcidiol (HyD, dsm-firmenich, Plainsboro, NJ), and 2.) a single dose of calcidiol was administered to cannulated heifers on nutrikinetic evaluation and predictive modeling simulations. In experiment 1, crossbred heifer calves [n = 96, initial body weight (BW) = 222 ± 12.4 kg] were assembled from auction markets near Dickson, TN and transported ~1,069 km to Manhattan, KS. Heifers (n = 12 per pen) were stratified by BW and randomly allocated to a corn-based receiving diet with one of four dietary treatments: 1) No supplemental D3 or calcidiol (CON, n = 24), 2) 3,000 IU supplemental D3·heifer⁻¹·d⁻¹ (D3, n = 24), 3.) 0.5 mg calcidiol/h/d (Hy D Low, n = 24), or 4.) 1.0 mg calcidiol·heifer⁻¹·d⁻¹ (Hy D High, n = 24) for 60 d. Blood samples were collected from each heifer prior to transport (d -1), on arrival (d 0) and on d 14, 31, and 60 of dietary treatment period. Data were analyzed using the GLIMMIX procedure of SAS using animal as experimental unit and treatment as fixed effect. HyD High calves had greater (P &amp;lt; 0.001) serum 25(OH)D3 concentrations than HyD Low at d 14 and 31 (Figure 1 and 2). At d 14, 31 and 60, HyD High and HyD Low calves had greater (P &amp;lt; 0.001) serum 25(OH)D3 concentrations than CON or D3 treatments. In experiment 2, cannulated crossbred heifers (n = 8, initial BW = 289 ± 44.9 kg were randomly assigned to one of two treatments: 1.) 3 mg/272 kg BW calcidiol, or 2.) 5 mg/272 kg BW calcidiol in a single dose administered via rumen cannula at h 0. Serial blood samples were collected at baseline out to 70 d post-dose. Serum 25(OH)D3 concentrations were analyzed via HPLC coupled with tandem MS (dsm-firmenich, Belvidere, NJ). Predictive modeling simulations of serum 25(OH)D3 concentrations used non-parametric superposition (Certara Phoenix WinNonlin 64, St. Louis, MO) from applying non-compartmental analysis with the assumptions of linearity, independent calcidiol dose response, and the rate of absorption and the average systemic clearance were consistent for each calcidiol dosing interval. The elimination half-life (t1/2) of calcidiol was determined to be an average of 7.1 d and area under change in concentration-time curve time 0 to the last time point that measured above baseline concentration post dose (AUC0-last) averaged of 32.6 d (Table 1). Non-parametric dosing simulations using nutrikinetic parameters from experiment 2 suggest that administration of two 5 mg oral doses of calcidiol with daily feeding of 1 mg would result in a rapid and sustained increase in serum 25(OH)D3. However, simulations should be confirmed in vivo before implementation.

Evaluation of levetiracetam loading dose in adult patients with benzodiazepine-refractory status epilepticus

BackgroundStatus epilepticus (SE) is a neurologic emergency defined as continued seizure activity greater than five minutes or recurrent seizure activity without return to baseline. Benzodiazepine-refractory SE is continuous seizure activity despite treatment with a benzodiazepine. Treatment of benzodiazepine-refractory SE includes levetiracetam with loading doses ranging from 20 mg/kg to 60 mg/kg up to a maximum dose of 4500 mg. While levetiracetam has minimal adverse effects, there is currently a lack of studies directly comparing the safety and efficacy of various loading doses of levetiracetam. ObjectiveThe objective of this study was to evaluate the safety and efficacy of three loading doses of levetiracetam in the setting of benzodiazepine-refractory SE. MethodsThis was a single center, retrospective cohort study of adult patients with benzodiazepine-refractory SE who were treated with levetiracetam from April 1, 2016, to August 31, 2023. Patients with documented hypersensitivity to levetiracetam, those who were pregnant or incarcerated and patients who received an alternative antiepileptic drug (AED) prior to levetiracetam were excluded. Patients with other identifiable causes of SE including hyperglycemia, hypoglycemia, hyponatremia or who were post cardiac arrest were also excluded. Patients were divided into three arms based on loading dose of levetiracetam administered (≤20 mg/kg [LEVlow], 21‐–39 mg/kg [LEVmed] or ≥40 mg/kg [LEVhigh]). The primary endpoint was the rate of seizure termination, defined as the lack of need for an additional AED within 60 min following levetiracetam administration. Secondary outcomes included the rate of intubation, and recurrent seizure activity 60 min to 24 h post seizure termination as defined by positive EEG results or need for an additional AED. Subgroup analyses were performed to assess the influence of adequate loading doses of benzodiazepines, and outpatient levetiracetam use. ResultsOverall, 740 patients were screened for inclusion, with 218 patients being included in the primary analysis. Patients were divided into three groups with an average levetiracetam loading dose of 14.5 mg/kg in the LEVlow group, 28.8 mg/kg in the LEVmed group, and 48.8 mg/kg in the LEVhigh group. There was no difference in rates of seizure termination at 60 min (92.9% LEVlow vs 89.3% LEVmed vs 84.7% LEVhigh; p = 0.377). Additionally, no difference was found in rates of recurrent seizure activity between 60 min and 24 h post levetiracetam loading dose (32.1% LEVlow vs 32.0% LEVmed vs 28.8% LEVhigh; p = 0.899). However, the LEVhigh group did have a higher rate of intubation (45.8%) compared to the LEVmed (28.2%) and LEVlow (26.8%) group (p = 0.040). ConclusionThe loading of levetiracetam did not result in a statistically significant difference in rate of seizure termination at 60 min nor did it appear to impact the rate of recurrent seizures at 24 h. However, we did find higher rates of intubation in patients who received levetiracetam >40 mg/kg. Further research is warranted to determine the optimal loading dose of levetiracetam in benzodiazepine-refractory SE.

TO ASSESS THE ROLE OF NASAL TAPENTADOL AS PRE-EMPTIVE ANALGESIA, IN BREAST SURGERY PATIENTS

Patients undergoes moderate to severe postoperative pain after surgery, which is troublesome during the postoperative period. Inadequately treated acute post operative pain causes prolonged morbidity to patients. Pre-emptive analgesic minimises the pain in perioperative period by central neuro sensitization. We assessed the role of Nasal Tapentadol in breast surgery patients, as a pre-emptive analgesic, in the reduction of post-operative analgesic requirement. In a double blinded prospective randomized control study, sixty breast surgery patients, received nasal spray of tapentadol (Group A) or saline Spray (Group B), 30 minutes prior to general anaesthesia. Perioperative analgesic requirement, time taken for first analgesic requirement in post operative period, post operative pain and sedation scores, we compared the following parameters in the first 24h during the postoperative period in all patients: Analgesic requirement during perioperative period, time taken for first post operative analgesic dose, pain score and sedation score in postoperative period.Data Of all sixty patients were analysed. Patients in Tapentadol Group A had significantly lower requirement of analgesics and lower Visual analog scale (VAS) than Saline group in the post operative period. However, Ramsay sedation score was more in Tapentadol group, immediately after shifting the patient to the postanaesthetic care unit. Single Pre-emptive nasal spray of tapentadol (45mg) is an effective intervention to, reduce the surgical pain and lesser requirement of analgesics, in post operative period, without added side effects.

Detection of pharmacolipidodynamic effects following the intravenous and oral administration of gefitinib to C57Bl/6JRj mice by rapid UHPLC-MS analysis of plasma

Omics-based biomarker technologies, including metabolic profiling (metabolomics/metabonomics) and lipidomics, are making a significant impact on disease understanding, drug development, and translational research. A wide range of patho-physiological processes involve lipids and monitoring changes in lipid abundance can give valuable insights into mechanisms of drug action, off target pharmacology and toxicity. Here we report changes, detected by untargeted LC–MS, in the plasma lipid profiles of male C57Bl/6JRj mice following the PO and IV administration of the epidermal growth factor receptor (EGFR) inhibitor gefitinib. Statistical analysis of the data obtained for both the IV and PO samples showed time-related changes in the amounts of lipids from several different classes. The largest effects were associated with a rapid onset of these changes following gefitinib administration followed by a gradual return by 24 h post dose to the type of lipid profile seen in predose samples. Investigation of the lipids responsible for the variance observed in the data showed that the PI, PC, LPC, PE and TG were subject to the largest disruption with both transient increases and decreases in relative amounts seen in response to administration of the drug. The pattern of the changes in the relative abundances of those lipids subject to variation appeared to be correlated to the pharmacokinetics of gefitinib (and its major metabolites). These observations support the concept of a distinct pharmacolipidodynamic relationship between drug exposure and plasma lipid abundance.

A deep learning-driven discovery of berberine derivatives as novel antibacterial against multidrug-resistant Helicobacter pylori

Helicobacter pylori (H. pylori) is currently recognized as the primary carcinogenic pathogen associated with gastric tumorigenesis, and its high prevalence and resistance make it difficult to tackle. A graph neural network-based deep learning model, employing different training sets of 13,638 molecules for pre-training and fine-tuning, was aided in predicting and exploring novel molecules against H. pylori. A positively predicted novel berberine derivative 8 with 3,13-disubstituted alkene exhibited a potency against all tested drug-susceptible and resistant H. pylori strains with minimum inhibitory concentrations (MICs) of 0.25–0.5 μg/mL. Pharmacokinetic studies demonstrated an ideal gastric retention of 8, with the stomach concentration significantly higher than its MIC at 24 h post dose. Oral administration of 8 and omeprazole (OPZ) showed a comparable gastric bacterial reduction (2.2-log reduction) to the triple-therapy, namely OPZ + amoxicillin (AMX) + clarithromycin (CLA) without obvious disturbance on the intestinal flora. A combination of OPZ, AMX, CLA, and 8 could further decrease the bacteria load (2.8-log reduction). More importantly, the mono-therapy of 8 exhibited comparable eradication to both triple-therapy (OPZ + AMX + CLA) and quadruple-therapy (OPZ + AMX + CLA + bismuth citrate) groups. SecA and BamD, playing a major role in outer membrane protein (OMP) transport and assembling, were identified and verified as the direct targets of 8 by employing the chemoproteomics technique. In summary, by targeting the relatively conserved OMPs transport and assembling system, 8 has the potential to be developed as a novel anti-H. pylori candidate, especially for the eradication of drug-resistant strains.

COVID-19 vaccine immunogenicity and safety surrounding fourth and subsequent vaccine doses in patients with hematologic malignancies

BackgroundImmune response to COVID-19 vaccine is diminished in patients with hematologic malignancy. There is limited data regarding response to vaccine doses in these patients. PurposeTo quantify the humoral immune response engendered by 4th and subsequent doses of SARS-CoV-2 vaccination as measured by anti-Spike (anti-S) antibody levels, based on dried blood spot (DBS) testing, in patients with hematologic malignancies. Anti-S binds to the spike protein of the SARS-CoV-2 virus and is indicative of vaccine immunogenicity. MethodsWe conducted a prospective study of hematologic malignancies between August 2021 and January 2023 at 12 sites across Canada. Participants were followed longitudinally and submitted finger-prick DBS cards at set intervals associated with vaccination. Samples were processed via high throughput ELISA assay to detect serum antibodies against nucleocapsid (N) and spike (S) proteins. ResultsWe obtained 3071 samples on 790 unique patients. Of these, 372 unique participants with 1840 samples had anti-S results available post-4th, 5th or 6th COVID-19 vaccine dose and were included for analysis.Three hundred thirty-three patients of the 372 participants submitted a DBS sample post 4th dose. Of these, 257 patients (77.2%) had a positive anti-S antibody. A total of 198 patients had paired samples pre- and post-dose 4, of which 59 (29.7%) had a negative anti-S antibody pre-dose 4. Of these, 20 (33.4%) developed positive anti-S antibody post-dose 4. One hundred forty-nine patients submitted a DBS sample post-dose 5. Of these, 135 patients (90.6%) had positive anti-S antibody. A total of 52 had paired samples pre- and post-dose 5. Six (8.7%) had a negative anti-S antibody pre-dose 5, of which two (33.3%) developed positive anti-S antibody post-dose 5.Of these 372 patients, 123 (34%) reported COVID-19 infection and 4 (1%) had a COVID-19 related hospitalization. There were no reported deaths from COVID-19. ConclusionsThis prospective cohort study showed that humoral immune response improved with subsequent doses of COVID-19 vaccines.

A phase 3, randomised, observer-blinded, placebo controlled-trial evaluating the safety and immunogenicity of investigational SARS-CoV-2 mRNA vaccine CVnCoV in adult healthcare workers in Mainz (Germany)

BackgroundCV-NCOV-005 was conducted to generate additional safety and immunogenicity data for the former CVnCoV SARS-CoV-2 mRNA vaccine candidate in healthcare workers (HCW). MethodsRandomised, observer blinded, placebo-controlled, phase 3 trial performed at the University Medical Center Mainz, Germany. HCWs aged ≥18 years with no history of SARS-CoV-2 infection/positive serology were randomly assigned to receive two doses of CVnCoV, or two doses of placebo (0.9% NaCl). The primary objectives were to expand the safety database of CVnCoV and assess antibody responses against SARS-CoV-2. Primary safety and reactogenicity outcomes included solicited adverse events (AEs) within 7 days after each dose and unsolicited AEs within 28 days after each dose, with safety follow-up for 13 months after first vaccination. Since HCWs became eligible to receive an authorised vaccine during enrolment and efficacy results from HERALD CVnCoV trial were made available on 30th of June 2021, this study was unblinded and converted to an open label design. ResultsMost participants in the CVnCoV group reported at least one solicited AE, a relatively high number being Grade 3 (43.3% in CVnCoV group and 6.4% in placebo group). Most AEs were short in duration and did not affect vaccine compliance. The percentage of participants with unsolicited AEs up to 28 days after any dose was slightly higher in CVnCoV group (37.0%) compared with placebo group (31.2%). IgG binding antibodies against the receptor binding domain of the SARS-CoV-2 spike protein were observed after vaccination, with higher seroconversion rates and antibody levels after the second dose. ConclusionNo safety concerns for CVnCoV were identified up to 1 year post second dose. IgG responses against SARS-CoV-2 were observed after two doses, with a higher seroconversion rate and antibody levels observed after second vaccination.Study registration: ClinicalTrials.gov NCT04674189, study period: 23rd of December 2020 to 8th of June 2022.

Predicting Efficacy of a Purified Inactivated Zika Virus Vaccine in Flavivirus-Naïve Humans Using an Immunological Correlate of Protection in Non-Human Primates.

A traditional phase 3 clinical efficacy study for a Zika vaccine may be unfeasible because of the current low transmission of Zika virus (ZIKV). An alternative clinical development approach to evaluate Zika vaccine efficacy (VE) is therefore required, delineated in the US FDA's Accelerated Approval Program for licensure, which utilizes an anti-Zika neutralizing antibody (Zika NAb) titer correlated with non-human primate (NHP) protection as a surrogate endpoint. In this accelerated approval approach, the estimation of VE would be inferred from the percentage of phase 3 trial participants achieving the established surrogate endpoint. We provide a statistical framework to predict the probability of protection for human participants vaccinated with a purified inactivated ZIKV vaccine (TAK-426), in the absence of VE measurements, using NHP data under a single-correlate model. Based on a logistic regression (LR) with bias-reduction model, a probability of 90% protection in humans is expected with a ZIKV NAb geometric mean titer (GMT) ≥ 3.38 log10 half-maximal effective concentration (EC50). The predicted probability of protection of TAK-426 against ZIKV infection was determined using the two-parameter LR model that fit the calculated VE in rhesus macaques and the flavivirus-naïve phase 1 trial participants' ZIKV NAb GMTs log10 EC50, measured by a ZIKV reporter virus particle assay, at 1 month post dose 2. The TAK-426 10 µg dose predicted a probability of protection from infection of 98% among flavivirus-naïve phase 1 trial participants.

In vitro and in vivo studies on the metabolism and pharmacokinetics of the selective gut microbial β-glucuronidase targeting compound Inh 1

In vitro studies using rat, mouse, and human microsomes and hepatocytes on the bacterial β-glucuronidase inhibitor 1-((6,8-dimethyl-2-oxo-1,2-dihydroquinolin-3-yl)methyl)-3-(4-ethoxyphenyl)-1-(2-hydroxyethyl)thiourea) (Inh 1) revealed extensive metabolism in all species. The intrinsic clearances of Inh 1 in human, mouse, and rat hepatic microsomes were 30.9, 67.8, and 201 µL/min/mg, respectively. For intact hepatocytes intrinsic clearances of 21.6, 96.0, and 129 µL/min/106 cells were seen for human, mouse and rat, respectively. The metabolism of Inh 1 involved an uncommon desulphurisation reaction in addition to oxidation, deethylation, and conjugation reactions at multiple sites. Six metabolites were detected in microsomal incubations in human and rat, and seven for the mouse. With hepatocytes, 18 metabolites were characterised, 9 for human, and 11 for mouse and rat. Following IV administration to mice (3 mg/kg), plasma concentrations of Inh 1 exhibited a monophasic decline with a terminal elimination half-life of 0.91 h and low systemic clearance (11.8% of liver blood flow). After PO dosing to mice (3 mg/kg), peak observed Inh 1 concentrations of 495 ng/mL were measured 0.5 h post dose, declining to under 10 ng/mL at 8 h post dose. The absolute oral bioavailability of Inh 1 in the mouse was ca. 26%.

Pharmacodynamics of venetoclax plus cirtuvivint a first-in-class splice variant regulator.

e15093 Background: NSC835563 (SM08502, cirtuvivint) is a first-in-class pan CDC-like kinase (CLK) and dual specificity tyrosine kinase (DYRK) inhibitor that targets alternative splicing of genes in multiple pathways and modifies their protein expression. Preclinical screening of hematologic malignancy models has shown sensitivity to cirtuvivint, leading to proposed clinical trials in AML in combinations with venetoclax. We performed pharmacodynamic studies to identify probable mechanisms of combination activity in AML models. Methods: In vivo tolerability, efficacy and pharmacodynamic (PD) studies were performed in two AML xenograft models, MV411 and KG1a in NSG mice, at 6.25-25 mg/kg PO cirtuvivint and 25 mg/kg PO venetoclax. Body weights (BW) and tumor volumes were recorded periodically to assess toxicity and anti-tumor efficacy. Tumor tissue samples were collected at 6 and 24 h post venetoclax to assess PD response. Multiplexed analysis of apoptosis pathway proteins/protein-protein complexes was performed by clinically validated assays (PMID 26446940). Results: Cirtuvivint alone at high doses (25 mg/kg) caused tumor regressions in MV411 but only a modest tumor growth inhibition (TGI) in KG1a, a resistant AM model. Importantly, the lowest dose of 6.25 mg/kg cirtuvivint combined with 25 mg/kg venetoclax led to tumor regression in the MV411 model and a moderate TGI in KG1a. Cirtuvivint alone caused a transient 25% reduction (p&lt;0.05) in Mcl-1 levels at 6 h post dose in MV411. The venetoclax combination triggered a sustained (for 24 h) 50-75% disruption of Bcl-2 and Mcl-1 complexes with Bax and Bim, resulting in &gt;20-fold increased mitochondrial Bax/Bak heterodimer and &gt;10-fold increased cytosolic cleaved caspase-3. In KG1a, combination treatment resulted in only modest (&lt;20%) changes in biomarkers. Overall, biomarkers provided evidence of the combination MoA. Conclusions: Venetoclax and cirtuvivint in combination effectively induced tumor regressions at low tolerable doses in an AML model. Mitochondrial Bax/Bak heterodimer provided a sensitive biomarker of combination activity. Cirtuvivint contributed its combinatorial effect primarily through disruption of Bim complexes and inhibition of Mcl-1. PD biomarkers identified in this study can confirm MoA of drug combination in ongoing clinical trials.

18-month longitudinal SARS COV-2 neutralizing antibody dynamics in haemodialysis patients receiving heterologous 3-dose vaccination (AZD-1222- AZD-1222- BNT162b2) in a lower middle income setting

BackgroundPatients with chronic kidney disease on haemodialysis (HD) were given priority COVID-19 vaccination due to increased disease risk. The immune response to COVID-19 vaccination in patients on HD was diminished compared to healthy individuals in 2-dose studies. This study aimed to evaluate seroconversion rate, neutralizing antibody (nAB) levels and longitudinal antibody dynamics to 3-dose heterologous vaccination against COVID-19 in a cohort of HD patients compared to healthy controls and assess patient factors associated with antibody levels.MethodsThis study was a case–control longitudinal evaluation of nAB dynamics in 74 HD patients compared to 37 healthy controls in a low/middle income setting. Corresponding samples were obtained from the two cohorts at time-points (TP) 1–1-month post 2nd dose of AZD1222 vaccine, TP2- 4 months post 2nd dose, TP4- 2 weeks post 3rd dose with BNT162b2 vaccine, TP5-5 months post 3rd dose and TP6-12 months post 3rd dose. Additional data is available at TP0- pre 2nd dose and TP3- 6 months post 2nd dose in HC and HD cohorts respectively. Anti-SARS-CoV-2 nAB were detected using Genscript cPassTM pseudoviral neutralization kit. Demographic and clinical details were obtained using an interviewer administered questionnaire.ResultsCohorts were gender matched while mean age of the HD cohort was 54.1yrs (vs HCs mean age, 42.6yrs, p < 0.05). Percentage seroconverted and mean/median antibody level (MAB) in the HD cohort vs HCs at each sampling point were, TP1-83.7% vs 100% (p < 0.05), MAB-450 IU/ml vs 1940 IU/ml (p < 0.0001); TP2-71.4% vs 100%, (p < 0.001), MAB- 235 IU/ml vs 453 IU/ml, (p < 0.05); TP4-95.2% vs 100% (p > 0.05), MAB-1029 IU/ml vs 1538 IU/ml (p < 0.0001); TP5-100% vs 100%, MAB-1542 IU/ml vs 1741IU/ml (p > 0.05); TP6-100% vs 100%, MAB-1961 IU/ml vs 2911 IU/ml (p > 0.05). At TP2, patients aged < 60 years (p < 0.001) were associated with maintaining seropositivity compared to patients > 60 years.ConclusionTwo dose vaccination of haemodialysis patients provided poor nAB levels which improved markedly following 3rd dose vaccination, the effect of which was long- lasting with high nAB levels in both patients and controls detectable at 1 year follow-up.

Tenofovir, emtricitabine, lamivudine and dolutegravir concentrations in plasma and urine following drug intake cessation in a randomized controlled directly observed pharmacokinetic trial to aid point-of-care testing.

Poor adherence to ART and pre-exposure prophylaxis (PrEP) can impact patient and public health. Point-of-care testing (POCT) may aid monitoring and adherence interventions. We report the pharmacokinetics of tenofovir [dosed as tenofovir disoproxil (TDF) and tenofovir alafenamide (TAF)], emtricitabine (FTC), lamivudine (3TC) and dolutegravir (DTG) in plasma and urine following drug cessation to evaluate adherence targets in urine for POCT. Subjects were randomized (1:1) to receive DTG/FTC/TAF or DTG/3TC/TDF for 15 days. Plasma and spot urine were collected on Day 15 (0-336 h post final dose). Drug concentrations were quantified using LC-MS, and non-linear mixed-effects models applied to determine drug disposition between matrices and relationship with relevant plasma [dolutegravir protein-adjusted 90% inhibitory concentration (PA-IC90 = 64 ng/mL) and minimum effective concentration (MEC = 324 ng/mL)] and urinary thresholds [tenofovir disoproxil fumarate 1500 ng/mL]. Of 30 individuals enrolled, 29 were included (72% female at birth, 90% Caucasian). Median (range) predicted time to plasma dolutegravir PA-IC90 and MEC were 83.5 (41.0-152) and 49.0 h (23.7-78.9), corresponding to geometric mean (90%) urine concentrations of 5.42 (4.37-6.46) and 27.4 ng/mL (22.1-32.7). Tenofovir in urine reached 1500 ng/mL by 101 h (58.6-205) with an equivalent plasma concentration of 6.20 ng/mL (4.21-8.18). These data support use of a urinary tenofovir threshold of <1500 ng/mL (tenofovir disoproxil fumarate-based regimens) as a marker of three or more missed doses for a POCT platform. However, due to low dolutegravir concentrations in urine, POCT would be limited to a readout of recent dolutegravir intake (one missed dose).

"Hurts less, lasts longer"; a qualitative study on experiences of young people receiving high-dose subcutaneous injections of benzathine penicillin G to prevent rheumatic heart disease in New Zealand.

Four-weekly intramuscular (IM) benzathine penicillin G (BPG) injections to prevent acute rheumatic fever (ARF) progression have remained unchanged since 1955. A Phase-I trial in healthy volunteers demonstrated the safety and tolerability of high-dose subcutaneous infusions of BPG which resulted in a much longer effective penicillin exposure, and fewer injections. Here we describe the experiences of young people living with ARF participating in a Phase-II trial of SubCutaneous Injections of BPG (SCIP). Participants (n = 20) attended a clinic in Wellington, New Zealand (NZ). After a physical examination, participants received 2% lignocaine followed by 13.8mL to 20.7mL of BPG (Bicillin-LA®; determined by weight), into the abdominal subcutaneous tissue. A Kaupapa Māori consistent methodology was used to explore experiences of SCIP, through semi-structured interviews and observations taken during/after the injection, and on days 28 and 70. All interviews were recorded, transcribed verbatim, and thematically analysed. Low levels of pain were reported on needle insertion, during and following the injection. Some participants experienced discomfort and bruising on days one and two post dose; however, the pain was reported to be less severe than their usual IM BPG. Participants were 'relieved' to only need injections quarterly and the majority (95%) reported a preference for SCIP over IM BPG. Participants preferred SCIP over their usual regimen, reporting less pain and a preference for the longer time gap between treatments. Recommending SCIP as standard of care for most patients needing long-term prophylaxis has the potential to transform secondary prophylaxis of ARF/RHD in NZ and globally.

Human bronchopulmonary disposition and plasma pharmacokinetics of oral bemnifosbuvir (AT-527), an experimental guanosine nucleotide prodrug for COVID-19.

Bemnifosbuvir (AT-527) is a novel oral guanosine nucleotide antiviral drug for the treatment of persons with COVID-19. Direct assessment of drug disposition in the lungs, via bronchoalveolar lavage, is necessary to ensure antiviral drug levels at the primary site of SARS-CoV-2 infection are achieved. This Phase 1 study in healthy subjects aimed to assess the bronchopulmonary pharmacokinetics, safety and tolerability of repeated doses of bemnifosbuvir. A total of 24 subjects were assigned to receive bemnifosbuvir twice daily at doses of 275, 550 or 825 mg for up to 3.5 days. AT-511, the free base of bemnifosbuvir, was largely eliminated from the plasma within 6 h post dose in all dosing groups. Antiviral drug levels of bemnifosbuvir were consistently achieved in the lungs with bemnifosbuvir 550 mg twice daily. The mean level of the guanosine nucleoside metabolite AT-273, the surrogate of the active triphosphate metabolite of the drug, measured in the epithelial lining fluid of the lungs was 0.62 µM at 4-5 h post dose. This exceeded the target in vitro 90% effective concentration (EC90) of 0.5 µM for antiviral drug exposure against SARS-CoV-2 replication in human airway epithelial cells. Bemnifosbuvir was well tolerated across all doses tested, and most treatment-emergent adverse events reported were mild in severity and resolved. The favourable pharmacokinetics and safety profile of bemnifosbuvir demonstrates its potential as an oral antiviral treatment for COVID-19, with 550 mg bemnifosbuvir twice daily currently under further clinical evaluation in persons with COVID-19.