Trough Levels Research Articles

Safety and pharmacokinetics of VRC07-523LS administered via different routes and doses (HVTN 127/HPTN 087): A Phase I randomized clinical trial.

Broadly neutralizing antibodies (bnAbs) are a promising approach for HIV-1 prevention. In the Antibody Mediated Prevention (AMP) trials, a CD4-binding site targeting bnAb, VRC01, administered intravenously (IV), demonstrated 75% prevention efficacy against highly neutralization-sensitive viruses but was ineffective against less sensitive viruses. VRC07-523LS is a next-generation bnAb targeting the CD4-binding site and was engineered for increased neutralization breadth and half-life. We conducted a multicenter, randomized, partially blinded Phase I clinical trial to evaluate the safety and serum concentrations of VRC07-523LS, administered in multiple doses and routes to healthy adults without HIV. Participants were recruited between 2 February 2018 and 9 October 2018. A total of 124 participants were randomized to receive 5 VRC07-523LS administrations via IV (T1: 2.5 mg/kg, T2: 5 mg/kg, T3: 20 mg/kg), subcutaneous (SC) (T4: 2.5 mg/kg, T5: 5 mg/kg), or intramuscular (IM) (T6: 2.5 mg/kg or P6: placebo) routes at 4-month intervals. Participants and site staff were blinded to VRC07-523LS versus placebo for the IM group, while all other doses and routes were open-label. Safety data were collected for 144 weeks following the first administration. VRC07-523LS serum concentrations were measured by ELISA through Day 112 in all participants and by binding antibody multiplex assay (BAMA) thereafter in 60 participants (10 per treatment group) through Day 784. Compartmental population pharmacokinetic (PK) analyses were conducted to evaluate the VRC07-523LS serum PK. Neutralization activity was measured in a TZM-bl assay and antidrug antibodies (ADAs) were assayed using a tiered bridging assay testing strategy. Injections and infusions were well tolerated, with mild pain or tenderness reported commonly in the SC and IM groups, and mild to moderate erythema or induration reported commonly in the SC groups. Infusion reactions were reported in 3 of 20 participants in the 20 mg/kg IV group. Peak geometric mean (GM) concentrations (95% confidence intervals [95% CIs]) following the first administration were 29.0 μg/mL (25.2, 33.4), 58.5 μg/mL (49.4, 69.3), and 257.2 μg/mL (127.5, 518.9) in T1-T3 with IV dosing; 10.8 μg/mL (8.8, 13.3) and 22.8 μg/mL (20.1, 25.9) in T4-T5 with SC dosing; and 16.4 μg/mL (14.7, 18.2) in T6 with IM dosing. Trough GM (95% CIs) concentrations immediately prior to the second administration were 3.4 μg/mL (2.5, 4.6), 6.5 μg/mL (5.6, 7.5), and 27.2 μg/mL (23.9, 31.0) with IV dosing; 0.97 μg/mL (0.65, 1.4) and 3.1 μg/mL (2.2, 4.3) with SC dosing, and 2.6 μg/mL (2.05, 3.31) with IM dosing. Peak VRC07-523LS serum concentrations increased linearly with the administered dose. At a given dose, peak and trough concentrations, as well as serum neutralization titers, were highest in the IV groups, reflecting the lower bioavailability following SC and IM administration. A single participant was found to have low titer ADA at a lone time point. VRC07-523LS has an estimated mean half-life of 42 days across all doses and routes (95% CI: 40.5, 43.5), over twice as long as VRC01 (15 days). VRC07-523LS was safe and well tolerated across a range of doses and routes and is a promising long-acting bnAb for inclusion in HIV-1 prevention regimens. ClinicalTrials.gov/ NCT03387150 (posted on 21 December 2017).

Silent Hearing Loss in Kidney Transplant Patients Receiving Tacrolimus: A Fact or a Myth?

Background: It has been claimed that tacrolimus may have harmful effects on the auditory system, where it has been linked to ototoxicity and sensorineural hearing loss (SNHL). We evaluated silent SNHL in kidney transplant recipients (KTRs) receiving tacrolimus and the different factors affecting it compared to healthy controls. Materials and Methods: In this case control study, hearing functions were studied in 42 KTRs receiving tacrolimus as maintenance immunosuppressive therapy for more than 3 months in comparison to 27 age- and gender-matched healthy subjects using tympanometry, pure-tone audiometry (PTA), extended high frequency audiometry (EHFA), and transient evoked oto-acoustic emissions (TEOAEs). Also, different factors were studied in relation to SNHL. Results: PTA showed that 23.8%, 21.4%, and 4.8% had mild, moderate, and severe SNHL, respectively. One-fifth of KTRs had severe SNHL, according to EHFA. According to TEOAEs, 28.6% of KTRs had abnormal hearing. There was a significant positive correlation between the tacrolimus trough levels and the results of both the PTA (P = 0.002) and EHFA (P = 0.035) tests. Conclusion: SNHL was detected in about half of the studied KTRs. Silent SNHL in KTRs might be associated with higher tacrolimus trough levels.

Evaluation of Empiric Voriconazole Dosing and Therapeutic Drug Monitoring in Hospitalized Pediatric Patients.

Invasive fungal infections are a significant cause of morbidity and mortality in children with immunodeficiencies. Current dosing recommendations for voriconazole often result in subtherapeutic exposure in pediatric patients. In this single-center retrospective study, we reviewed hospitalized pediatric patients receiving voriconazole with at least one inpatient serum trough concentration measured. Patient characteristics and voriconazole dosing courses with associated trough concentrations were summarized for all patients as well as grouped by age (0 to 1 y, 2 to 11 y, and 12 to 18 y). Of 106 included patients, the median age was 9 years (range, 29 d to 18 y). Five hundred ninety courses of voriconazole were administered with 365 associated troughs. Most troughs were subtherapeutic (49%) and 30% of patients never attained a therapeutic trough. The median oral daily dose associated with a therapeutic trough was higher in younger age groups: 21.6 mg/kg 0 to 1 year, 17.9 mg/kg 2 to 11, and 9.5 mg/kg 12 to 18 years ( P <0.001). Patients younger than 2 years had the largest proportion of subtherapeutic troughs and variability in dosing. Attainment of therapeutic voriconazole concentrations was challenging across all pediatric age groups. Higher starting doses for patients younger than 2 years are likely needed.

Pharmacodynamic Effect of mTOR Inhibition-based Immunosuppressive Therapy on T- and B-cell Subsets After Renal Transplantation.

The mammalian target of rapamycin inhibitor (mTORi) therapy after kidney transplantation is solely monitored pharmacokinetically, not necessarily reflecting PI3K-Akt-mTOR pathway blockade efficacy leading to potential under-or overimmunosuppression. In this cross-sectional study, phosphoflow cytometry was used to determine the efficacy of mTOR inhibition in peripheral T- and B-lymphocyte subsets by assessing p70S6 kinase (p70S6K) phosphorylation in renal transplant recipients upon treatment with a combination of either mTORi and calcineurin inhibitors (n = 18), or mTORi with mycophenolic acid (n = 9). Nine dialysis patients with end-stage renal disease and 17 healthy age-matched volunteers served as controls. mTORi treatment reduced p70S6K phosphorylation in CD4+, CD8+ T, and CD19+ B cells compared with healthy controls (HCs). Subpopulation analysis of CD4+ T cells and CD19+ B cells revealed a significant reduction of p70S6K phosphorylation in CD4+CD45RA-CD25- Th cells (P < 0.05), CD24hiCD38hi transitional B cells (P < 0.001), CD24+CD38- memory B cells (P < 0.001), and CD24intCD38int-naive B cells (P < 0.05) upon mTORi treatment, whereas CD4+CD45RA-CD25++CD127- regulatory T cells and CD24-CD38hi plasmablasts were not affected. Compared with mTORi + mycophenolic acid therapy, mTORi + calcineurin inhibitor treatment exhibited an even stronger inhibition of p70S6K phosphorylation in CD4+CD45RA-CD25- Th cells and CD8+ T cells. However, trough levels of mTORi did not correlate with p70S6K phosphorylation. mTORi selectively inhibited p70S6K phosphorylation in select lymphocyte subtypes. Assessing p70S6K phosphorylation by phosphoflow cytometry may serve as an approach to understand cell subset specific effects of mTORi providing detailed pharmacodynamic information for individualizing immunosuppression.

Gestational buprenorphine-naloxone exposure and fetal neurobehavior

BackgroundBuprenorphine-naloxone treatment may confer substantial benefits for the treatment of opioid use disorder (OUD) during pregnancy including lower risk for overdose/death, less diversion potential and reduced use of other substances. Treatment may also result in less severe Neonatal Abstinence Syndrome (NAS), but little is known about the effects of this medication on fetal neurodevelopment. MethodsThe purpose of the current study is to evaluate neurobehaviors among fetuses exposed to buprenorphine-naloxone at four time points over the second and third trimesters of gestation in pregnant women with OUD on buprenorphine-naloxone therapy. Sixty minutes of continuous fetal monitoring via fetal actocardiograph with a single wide array abdominal transducer took place at times of peak and trough buprenorphine-naloxone levels in 24 pregnant women. Data collection, which included measures of fetal heart rate and motor activity, was conducted between 24 and 36 weeks gestation, with the majority (84.6%) monitored at two or more gestational ages. Medication dose and other substance use was monitored throughout the study and infant NAS severity was assessed. ResultsFetal heart rate (FHR), FHR variability, accelerations in FHR, and motor activity were suppressed when buprenorphine-naloxone levels were at pharmacologic peak as compared to trough concentrations at 36 weeks, but not earlier in gestation. Maternal medication dose was unrelated to infant NAS severity. ConclusionsConclusions: There were evident subclinical fetal neurophysiological responses at times of peak maternal buprenorphine/naloxone levels in later gestation, similar to those previously described for buprenorphine only. Further studies evaluating the effects of these changes in fetal neurobehaviors on the longer-term infant development are needed.

Constitutional DNA Polymorphisms Associated with the Plasma Imatinib Concentration in Chronic Myeloid Leukemia Patients

The tyrosine kinase Inhibitor (TKI) imatinib is approved for the treatment of the chronic phase of chronic myeloid leukemia (CP-CML). Pharmacokinetic studies have highlighted the importance of inter-patient variability on imatinib plasma trough concentrations (ima[C]min). In the OPTIM-imatinib trial, we demonstrated that therapeutic drug monitoring (TDM) is able to improve the molecular response of CP-CML patients treated with imatinib. Here, we analyzed the constitutional exomes and RNAseq data of these patients. We performed an association analysis between the constitutional genetic variants of the patients and their ima[C]min, measured after 12 weeks of treatment with 400 mg once daily. Using linear regression, we identified 50 SNPs that showed excess heterozygosity depending on the ima[C]min. Ten SNPs were from non-coding sequences, and among the 40 remaining, 30 (from 25 genes) could be split into two categories. The first group of 16 SNPs concerns genes encoding extracellular matrix, cell junction, and membrane proteins. Coincidentally, cell adhesion proteins were also identified by RNA-seq as being overexpressed in patients with high ima[C]min. The other group of 14 SNPs were from genes encoding proteins involved in transcription/translation. Although most of the SNPs are intronic variants (28), we also identified missense (3), synonymous (4), 5′/3′ (2), splicing (1), and upstream (4) variants. A haplotype analysis of four genes showed a significant association with high ima[C]min. None of the SNPs were significantly associated with the response. In conclusion, we identified a number of ima[C]min-associated SNPs, most of which correspond to genes encoding proteins that could play a role in the diffusion and transit of imatinib through membranes or epithelial barriers.

Tacrolimus personalized therapy based on CYP3A5 genotype in Chinese patients with idiopathic inflammatory myopathies.

Idiopathic inflammatory myopathies (IIM) are a heterogeneous and life-threatening group of diseases; in particular, anti-melanoma differentiation-associated gene 5 antibody positive DM (MDA5+ DM) is reportedly strongly associated with high mortality rate. Tacrolimus (TAC) provides an excellent therapeutic option, but the trough concentration (Cmin)-outcome relationship remains unexplored. This study was undertaken to identify optimal Cmin and individualized dose based on CYP3A5 genotype for IIM patients. A total of 134 IIM patients with 467 Cmin were enrolled. We examined the relationship between TAC Cmin and relapses. The receiver operating characteristic analysis was used to confirm the optimal Cmin. Analyses of factors influencing Cmin were conducted. The dose requirement based on CYP3A5 genotype was confirmed. TAC Cmin is strongly associated with relapses. The optimal cutoff values were 5.30, 5.85, 4.85 and 5.35 ng/ml for acute, subacute, chronic and all-phase IIM patients (P = 0.001, 0.013, 0.002 and <0.001, respectively), as well as 5.35, 5.85, 5.55 and 5.85 ng/ml for acute, subacute, chronic and all-phase MDA5+ DM patients (P = 0.007, 0.001, 0.036 and <0.001, respectively). CYP3A5 genotype was one of the significant factors influencing TAC Cmin. CYP3A5 expressers required 0.059 mg/kg/day to attain the target Cmin, while nonexpressers required 0.046 mg/kg/day (P = 0.019). TAC treatment may elicit favorable outcome in patients with IIM and MDA5+ DM when Cmin exceeded 5.35 and 5.85 ng/ml, which is crucial to a lower relapse rate. The individualized dose based on the CYP3A5 genotype provides a reference for TAC personalized therapy in IIM.

Model-Informed Development of a Cost-Saving Dosing Regimen for Sacituzumab Govitecan.

The antibody-drug conjugate sacituzumab govitecan is approved for metastatic triple-negative breast cancer and has shown promising results in various other types of cancer. Its costs may limit patient access to this novel effective treatment modality. The purpose of this study was to develop an evidence-based rational dosing regimen that results in targeted drug exposure within the therapeutic range while minimizing financial toxicity, to improve treatment access. Exposure equivalent dosing strategies were developed based on pharmacokinetic modeling and simulation by using the published pharmacokinetic model developed by the license holder. The alternative dose was based on the principle of using complete vials to prevent spillage and on the established non-linear relationship between body weight and systemic exposure. Equivalent exposure compared to the approved dosing regimen of 10 mg/kg was aimed for. Equivalent exposure was conservatively defined as calculated geometric mean ratios within the 0.9-1.11 boundaries for area under the concentration-time curve (AUC), trough concentration (Ctrough) and maximum concentration (Cmax) of the alternative dosing regimen compared to the approved dosing regimen. Since different vial sizes are available for the European Union (EU) and United States (US) market, because body weight distributions differ between these populations, we performed our analysis for both scenarios. Dosing regimens of sacituzumab govitecan for the EU (<50 kg: 400 mg, 50-80 kg: 600 mg, and >80 kg: 800 mg) and US population (<40 kg: 360 mg, 40-65 kg: 540 mg, 65-90 kg: 720 mg, and >90 kg: 900 mg) were developed, based on weight bands. The geometric mean ratios for all pharmacokinetic outcomes were within the predefined equivalence boundaries, while the quantity of drug used was 21.5% and 19.0% lower for the EU and US scenarios, respectively. With the alternative dosing proposal, an approximately 20% reduction in drug expenses for sacituzumab govitecan can be realized while maintaining an equivalent and more evenly distributed exposure throughout the body weight range, without notable increases in pharmacokinetic variability.

Optimum tacrolimus trough levels for enhanced graft survival and safety in kidney transplantation: a retrospective multicenter real-world evidence study.

The current study aimed to determine the optimal tacrolimus trough levels for balancing graft survival and patient safety following kidney transplantation. We conducted a retrospective cohort study involving 11,868 kidney transplant recipients from five medical centers. The association between tacrolimus exposures (periodic mean trough level, coefficient of variability, time in therapeutic range) and composite allograft outcome (de novo donor specific antibody, biopsy-proven rejection, kidney dysfunction, and graft failure), as well as safety outcomes (severe infection, cardiovascular events, malignancy, and mortality) were assessed. Data were sourced from Clinical Data Warehouses and analyzed using advanced statistical methods, including Cox marginal structural models with inverse probability treatment weighting. Tacrolimus levels of 5.0-7.9ng/mL and 5.0-6.9ng/mL during the 2-12 month and 12-72 month post-transplantation periods, respectively, were associated with reduced risks of composite allograft outcomes. During the first post-transplant year, the adjusted hazard ratios (aHR) for composite allograft outcomes were: 0.69 (95% CI 0.55-0.85, P<0.001) for 5.0-5.9ng/mL; 0.81 (95% CI 0.67-0.98, P=0.033) for 6.0-6.9ng/mL; and 0.73 (95% CI 0.60-0.89, P=0.002) for 7.0-7.9ng/mL (compared to levels ≥8.0ng/mL). For the 6-year composite outcomes, aHRs were 0.68 (95% CI 0.53-0.87, P=0.002) for 5.0-5.9ng/mL and 0.65 (95% CI 0.50-0.85, P=0.001) for 6.0-6.9ng/mL. These optimal ranges showed reduced rates of severe infection (6y), malignancy (6y), and mortality (1y). This multicenter study provides robust evidence for optimal tacrolimus trough levels during the periods 2-12 and 12-72 months following kidney transplantation.

New coronavirus infection SARS-CoV-2 in adult patients with inborn errors of immunity

BACKGROUND: Diagnosis and treatment of COVID-19 in patients with primary immunodeficiency, or inborn errors of immunity, are often challenging. AIM: Description of the COVID-19 course and therapy of adult patients with primary immunodeficiency treated in medical organizations of Moscow Healthcare Department. MATERIALS AND METHODS: We analyzed a cohort of 68 patients over 18 years (median ― 35 years) with primary immunodeficiency; 91% of patients have primary immunodeficiency with predominantly antibody deficiencies. Altogether 90 cases of the new СOVID-19 were analyzed: in 68 cases infection occurred for the first time, in 22 cases it recurred. The duration of the disease ranged from 3 to 80 days. Duration of PCR-positivity ranged from 0 to 59 days, median 8 days. RESULTS: Patients with Wuhan and Delta strains had more severe inflammatory signs according to C-reactive protein and lactate dehydrogenase, in patients with Wuhan lung involvement on CT-scam was larger. In demonstrated group of patients higher C-reactive protein correlated with larger lung involvement, longer duration of the disease and PCR-positivity, significant lymphopenia also correlated with higher C-reactive protein. To our data regularity of intravenous immunoglobulin therapy and IgG trough level didn’t correlate with infection severity and duration of the disease and virus-carriage. Indirectly, the change in the spectrum of medicine used in patients of the analyzed group coincided with the virus strain evolution. Anti-inflammatory therapy was mainly presented by dexamethasone and antagonists to interleukin 6 or its receptor (anti-IL-6): 55% and 73% for Wuhan, 63% and 50% for Delta, 17% and 39% for Omicron. Then, preference was gradually given to the target anti-cytokine medicine. Etiotropic antiviral therapy was more often used to treat infection caused by Wuhan and Delta strains ― 32% and 38%, respectively (in 17% for Omicron). With shifting toward immunotherapy by specific against COVID-19 immunoglobulins and monoclonal antibody to SARS-CoV-2: 5% and 9% for Wuhan, 0% and 75% for Delta, 48% and 83% for Omicron, respectively. Immune and etiotropic therapy was not carried out in Wuhan in 39%, in Delta in 43%, in Omicron in 41% of cases. The overall mortality rate from COVID-19 in the analyzed group was 3%. CONCLUSION: Patients with primary immunodeficiency represent a vulnerable group to the SARS-CoV-2 virus with a high risk of not only severe, but also a protracted and undulating course of infection, what must be taken into account for the correct interpretation of the patient's condition and the timely administration of the appropriate therapy.

Therapeutic drug monitoring of linezolid and exploring optimal regimens and a toxicity-related nomogram in elderly patients: a multicentre, prospective, non-interventional study.

The concentrations of linezolid, its optimal regimen and the associated side effects in elderly patients remain unclear. In this multicentre, prospective study, elderly patients receiving linezolid at four tertiary hospitals in Beijing between May 2021 and December 2022 were included. Linezolid concentrations and haematological toxicity were monitored dynamically. Risk factors for linezolid overexposure and moderate-to-severe linezolid-induced thrombocytopenia (M/S LIT) were analysed, and a predictive model of M/S LIT was developed. A total of 860 linezolid concentrations were measured in 313 patients. The median trough concentrations of linezolid were 24.4 (15.3, 35.8) mg/L at 36-72 h and 26.1 (17.0, 38.1) mg/L at 5-10 days (P = 0.132). Severe linezolid exposure was independently associated with age, estimated glomerular filtration rate (eGFR) and the worst SOFA score (SOFA1), and we further recommended dose regimens for elderly patients based on these findings. The incidences of linezolid-induced thrombocytopenia(LIT) and M/S LIT were 73.5% and 47.6%, respectively. M/S LIT was independently correlated with treatment duration, average trough concentration (TDMa), baseline platelet count, eGFR and baseline SOFA score (SOFA0). The developed nomogram predicted M/S LIT with an area under the curve of 0.767 (95% CI 0.715-0.820), a sensitivity of 71.1% and a specificity of 73.2%. Linezolid trough concentrations increased dramatically in the elderly, by about 10 mg/L in patients aged 65-80 years, followed by a further increase of 10 mg/L for every 10 years of age. Therapeutic drug monitoring is recommended in elderly patients receiving linezolid. The developed nomogram may predict M/S LIT and guide dosage adjustments of linezolid. Clinical trial registration number: ChiCTR2100045707.

Optimizing vancomycin dosing in pediatrics: a machine learning approach to predict trough concentrations in children under four years of age.

Vancomycin trough concentration is closely associated with clinical efficacy and toxicity. Predicting vancomycin trough concentrations in pediatric patients is challenging due to significant inter-individual variability and rapid physiological changes during maturation. This study aimed to develop a machine learning model to predict vancomycin trough concentrations and determine optimal dosing regimens for pediatric patients < 4years of age using ML algorithms. A single-center retrospective observational study was conducted from January 2017 to March 2020. Pediatric patients who received intravenous vancomycin and underwent therapeutic drug monitoring were enrolled. Seven ML models [linear regression, gradient boosted decision trees, support vector machine, decision tree, random forest, Bagging, and extreme gradient boosting (XGBoost)] were developed using 31 variables. Performance metrics including R-squared (R2), mean square error (MSE), root mean square error (RMSE), and mean absolute error (MAE) were compared, and important features were ranked. The study included 120 eligible trough concentration measurements from 112 patients. Of these, 84 measurements were used for training and 36 for testing. Among the seven algorithms tested, XGBoost showed the best performance, with a low prediction error and high goodness of fit (MAE = 2.55, RMSE = 4.13, MSE = 17.12, and R2 = 0.59). Blood urea nitrogen, serum creatinine, and creatinine clearance rate were identified as the most important predictors of vancomycin trough concentration. An XGBoost ML model was developed to predict vancomycin trough concentrations and aid in drug treatment predictions as a decision-support technology.

A Retrospective Study Evaluating Neonatal Vancomycin Loading Doses to Achieve a Therapeutic Target

Background: Vancomycin is a glycopeptide antibiotic that has been used to treat hospital-acquired gram-positive infections for more than 5 decades. However, the literature is divided regarding the therapeutic advantages of vancomycin loading doses in neonates. Objectives: This study aimed to investigate the effect of vancomycin loading doses on therapeutic target attainment in neonates with sepsis. Methods: A retrospective cohort study was conducted to compare the vancomycin target attainment (area under the curve 0–24 hours/minimum inhibitory concentration ≥400) in neonates before and after the 2019 change in vancomycin prescription guidelines at a neonatal unit in Cape Town, South Africa. As the standard of care, Bayesian modelling software was used to compute the area under the curve from the trough concentrations. Results: Two hundred ten neonates were included. Multivariate regression analysis showed a 2-fold increase in the odds of target attainment among neonates receiving a loading dose of vancomycin. Early target attainment (within 8–12 hours of treatment initiation) was significantly higher in the loading dose group compared with the no loading dose group [97/105 (92.4%) versus 64/105 (61.0%); P &lt; 0.001]. However, the overall proportion of neonates achieving target attainment at 24 hours was similar between groups [73/105 (69.5%) in the loading dose group versus 62/105 (59.0%) in the no loading dose group; P = 0.110]. The nephrotoxicity rates were low [2/105 (1.9%) in the loading dose group and 2/105 (1.9%) in the no loading dose group]. Conclusions: The addition of a vancomycin loading dose to neonates may facilitate early therapeutic target attainment.

Proactive monitoring of drug–drug interactions between direct oral anticoagulants and small-molecule inhibitors in patients with non-small cell lung cancer

BackgroundSmall-molecule inhibitors (SMIs) have revolutionised the treatment of non-small cell lung cancer (NSCLC). However, SMI-induced drug–drug interactions (DDIs) with frequently co-administered direct oral anticoagulants (DOACs), increase thromboembolic and bleeding risks. This study investigated and proactively managed the consequences of DOAC-SMI DDIs.MethodsThis prospective, observational study enrolled patients with NSCLC concomitantly using a DOAC and SMI. The primary outcome was the proportion of patients with DOAC plasma trough (Ctrough) and peak (Cpeak) concentrations outside expected ranges. Secondary outcomes included DOAC treatment modifications, incidence of bleeding and thromboembolic events and feasibility evaluation of pharmacokinetically guided DOAC dosing.ResultsThirty-three patients were analysed. Thirty-nine percent (13/33) had DOAC Ctrough and/or Cpeak were outside the expected ranges in 39% (13/33). In 71% (5/7) of patients with DOAC concentrations quantified before and during concurrent SMI use, DOAC Ctrough and/or Cpeak increased or decreased >50% upon SMI initiation. In all patients in whom treatment modifications were deemed necessary, DOAC concentrations were adjusted to within the expected ranges.ConclusionProactive monitoring showed that a substantial proportion of patients had DOAC concentrations outside the expected ranges. DOAC concentrations were successfully normalised after treatment modifications. These results highlight the importance of proactive monitoring of DOAC-SMI DDIs to improve treatment in patients with NSCLC.

Influence of geometric design variables on the performance of a novel V-shaped cavity receiver

This study presents a novel cavity receiver for parabolic trough concentrators, incorporating a triangular envelope, a trapezoidal cavity, and a semi-circular flow channel. A total of 5120 designs were examined by tuning the rim angle of parabolic mirrors, the width and angle of the receiver's opening, and the depth of the absorber for different operating flow rates and temperatures. Batch simulations of these designs were automated by coupling newly developed and validated models of Monte Carlo ray tracing and semi-analytical 1-D energy balances in SOLTRACE® and MATLAB® to determine the heat fluxes and surface temperatures of the receiver, respectively. The results show that the rim angle must be reduced to maximize sun rays' interception, and the opening angle has the largest impact on performance. All dimensions must be decreased when operating at low flow rates and high temperatures to avoid excessive thermal losses. This results in maximum energy and exergy efficiencies of 74.7 % and 40.7 %, respectively. When operating at low temperatures and large flow rates, the largest energy and exergy efficiencies increase and decrease to 80.5 % and 27 %, corresponding to optimal rim angle, absorber depth, opening width, and opening angle of 60°, 85 mm, 200 mm, and 100°, respectively.

Subcutaneous amivantamab vs intravenous amivantamab, both in combination with lazertinib, in refractory EGFR-mutated, advanced non-small cell lung cancer (NSCLC): Primary results, including overall survival (OS), from the global, phase 3, randomized controlled PALOMA-3 trial.

LBA8505 Background: Amivantamab (ami) plus lazertinib (laz) demonstrated antitumor activity in EGFR-mutated advanced NSCLC. Subcutaneous (SC) ami administration takes ≤7 mins and has low infusion-related reaction (IRR) rates. PALOMA-3 (NCT05388669) evaluated SC ami+laz vs IV ami+laz for pharmacokinetics (PK), efficacy, and safety among pts with EGFR Ex19del or L858R-mutated advanced NSCLC and disease progression on osimertinib and platinum-based chemotherapy. Methods: SC ami at 1600 mg (2240 mg, ≥80 kg) was manually injected weekly for the first 4 weeks, then every 2 weeks; IV ami was given at the approved dose of 1050 mg (1400 mg, ≥80 kg). Laz was orally dosed at 240 mg daily. Co-primary PK noninferiority endpoints were trough concentration (Ctrough on Cycle [C] 2 Day [D] 1 or C4D1) and C2 area under the curve (AUCD1-D15). Key secondary endpoints were objective response rate (ORR; noninferior) and progression-free survival (PFS). OS was a predefined exploratory endpoint. Prophylactic anticoagulation was recommended for the first 4 months (mo) of treatment. Results: In total, 418 patients (pts) were randomized (SC, n = 206; IV, n = 212); 416 received ≥1 dose. Overall, median age was 61 years, 67% were female, 61% Asian, and median 2 prior lines. At a median follow-up of 7.0 mo, PALOMA-3 met both co-primary endpoints. Geometric mean ratios (GMRs) comparing SC ami+laz vs IV for Ctrough were 1.15 (90% CI, 1.04–1.26) for C2D1 and 1.43 (90% CI, 1.27–1.61) for C4D1. GMR for C2 AUCD1-D15 was 1.03 (90% CI, 0.98–1.09). ORR was 30.1% (95% CI, 24–37) in the SC arm and 32.5% (95% CI, 26–39) for IV (relative risk, 0.92; P= 0.001), meeting the noninferiority criteria. Median duration of response (DoR) was longer for SC ami+laz vs IV (median, 11.2 vs 8.3 mo among confirmed responders). A favorable PFS trend was observed for SC ami+laz over IV (median, 6.1 vs 4.3 mo; HR, 0.84; P= 0.20). OS was notably longer for SC ami+laz vs IV (HR, 0.62; 95% CI, 0.42–0.92; nominal P= 0.017). At 12 mo, 65% were alive in the SC arm vs 51% for IV. IRRs were ~5-fold lower in the SC arm: 13% vs 66% for IV, primarily grade 1-2 (0.5% vs 4% grade ≥3, respectively). Overall, 81% received prophylactic anticoagulants, with VTE reported by 9% in the SC arm vs 14% for IV. Across both arms, VTE incidence was 10% for pts who received prophylactic anticoagulants vs 21% for pts who did not. Severe bleeding risk was low among all pts receiving anticoagulants (1% grade ≥3). Conclusions: SC ami demonstrated noninferior PK and ORR compared to IV. Unexpectedly, DoR, PFS, and OS were longer in the SC arm vs IV, suggesting that the route of administration or formulation may affect outcomes. The safety profile was improved for SC ami, with lower IRR and VTE rates. Prophylactic anticoagulation can be safely implemented and reduces VTE risk. Clinical trial information: NCT05388669 .

Subcutaneous Versus Intravenous Amivantamab, Both in Combination With Lazertinib, in Refractory Epidermal Growth Factor Receptor-Mutated Non-Small Cell Lung Cancer: Primary Results From the Phase III PALOMA-3 Study.

Phase III studies of intravenous amivantamab demonstrated efficacy across epidermal growth factor receptor (EGFR)-mutated advanced non-small cell lung cancer (NSCLC). A subcutaneous formulation could improve tolerability and reduce administration time while maintaining efficacy. Patients with EGFR-mutated advanced NSCLC who progressed after osimertinib and platinum-based chemotherapy were randomly assigned 1:1 to receive subcutaneous or intravenous amivantamab, both combined with lazertinib. Coprimary pharmacokinetic noninferiority end points were trough concentrations (Ctrough; on cycle-2-day-1 or cycle-4-day-1) and cycle-2 area under the curve (AUCD1-D15). Key secondary end points were objective response rate (ORR) and progression-free survival (PFS). Overall survival (OS) was a predefined exploratory end point. Overall, 418 patients underwent random assignment (subcutaneous group, n = 206; intravenous group, n = 212). Geometric mean ratios of Ctrough for subcutaneous to intravenous amivantamab were 1.15 (90% CI, 1.04 to 1.26) at cycle-2-day-1 and 1.42 (90% CI, 1.27 to 1.61) at cycle-4-day-1; the cycle-2 AUCD1-D15 was 1.03 (90% CI, 0.98 to 1.09). ORR was 30% in the subcutaneous and 33% in the intravenous group; median PFS was 6.1 and 4.3 months, respectively. OS was significantly longer in the subcutaneous versus intravenous group (hazard ratio for death, 0.62; 95% CI, 0.42 to 0.92; nominal P = .02). Fewer patients in the subcutaneous group experienced infusion-related reactions (IRRs; 13% v 66%) and venous thromboembolism (9% v 14%) versus the intravenous group. Median administration time for the first infusion was reduced to 4.8 minutes (range, 0-18) for subcutaneous amivantamab and to 5 hours (range, 0.2-9.9) for intravenous amivantamab. During cycle-1-day-1, 85% and 52% of patients in the subcutaneous and intravenous groups, respectively, considered treatment convenient; the end-of-treatment rates were 85% and 35%, respectively. Subcutaneous amivantamab-lazertinib demonstrated noninferiority to intravenous amivantamab-lazertinib, offering a consistent safety profile with reduced IRRs, increased convenience, and prolonged survival.

Clinical pharmacokinetics and pharmacodynamics of empagliflozin in patients with heart failure.

The aim of this work is to compare empagliflozin systemic exposure between patients with heart failure (HF) and patients with type 2 diabetes (T2D). Analysis of covariance (ANCOVA) compared steady state trough concentrations of empagliflozin 10mg in EMPEROR-reduced (patients with HF with reduced ejection fraction [HFrEF]) and EMPA-REG OUTCOME (patients with T2D at high cardiovascular risk) after adjusting for eGFR and body weight. The difference in geometric Mean (gMean) empagliflozin steady state trough concentration of 10mg empagliflozin between EMPEROR-reduced and EMPA-REG OUTCOME was 1.47-fold (95% confidence interval [CI]: 1.33, 1.63). Additionally, ANCOVA for the sub-group of patients with both T2D and HF conditions revealed a difference in gMean steady state trough concentration of 1.53-fold (95% CI: 1.26, 1.85). In both patients with HFrEF and HF with preserved EF (HFpEF), there was no major difference in empagliflozin steady state trough exposure by New York Heart Association (NYHA) classification or by use of angiotensin receptor-neprilysin inhibitor as comedication. A weak positive correlation was observed for NT-proBNP at Week 12 and empagliflozin steady state trough concentration in both patients with HFrEF and HFpEF (Pearson correlation r = 0.19). Plasma concentrations of empagliflozin in patients with HF were higher compared to patients with T2D, but the exposure resulting from the 10mg dose was still below the exposure resulting from the dose of 25 mg approved in patients with T2D. The difference in exposure was attributable to demographic characteristics and HF-induced pathophysiological changes. Overall, the results confirm 10mg as the appropriate empagliflozin dose in patients with HF.

A case of successful contribution of therapeutic drug monitoring of valganciclovir as the prophylaxis against cytomegalovirus infection in a lung transplant recipient

BackgroundGanciclovir and its prodrug, valganciclovir, are first-line agents for cytomegalovirus infection prophylaxis after lung transplantation. Although valganciclovir prophylaxis is known to result in severe leukopenia as an adverse effect, dosage adjustment based on therapeutic drug monitoring (TDM) of ganciclovir concentration is not generally implemented in clinical practice.Case presentationIn this report, we describe the case of a female in her fifties after lung transplantation who successfully maintained valganciclovir prophylaxis under TDM with a minimal occurrence of severe leukopenia. Valganciclovir administration was initiated at a conventional dose of 450 mg/day on postoperative day 43 but was reduced to 450 mg/2 days on postoperative day 69 because of a decrease in white blood cell count and an increase in trough ganciclovir concentration. Subsequently, the valganciclovir dose adjustment was switched from label-indicated renal function-guided dosing to TDM-based dosing, targeting a trough level of 300–800 ng/mL. This target range was determined through deliberations with infectious disease specialists and pharmacists based on previously reported data. The TDM-based dose adjustment successfully prevented cytomegalovirus reactivation without causing significant adverse effects. Valganciclovir prophylaxis was completed on postoperative day 256, and the patient was transferred to another hospital for rehabilitation.ConclusionsThe findings of the present case suggest that TDM-based dosing could be helpful for clinicians in optimizing the prophylactic administration of valganciclovir in patients undergoing lung transplantation.

Association between prolonged vancomycin infusion and trough concentrations in children. Retrospective study.

Introduction: This study investigated the serum concentration of vancomycin during prolonged infusion in children. Population and methods: This retrospective cohort study included pediatric patients who received vancomycin from June 2017 to June 2020 at a tertiary referral hospital. The patients were divided into two groups according to infusion strategy, the SII (standard intermittent infusion) group and the PI (prolonged infusion) group. Demographic details, infusion period, serum creatinine, duration of vancomycin therapy, trough concentration of vancomycin, and pediatric intensive care unit stay were reviewed. Differences of the concentrations were measured. Results: Sixty-eight patients were included: 31 in the SII group and 37 in the PI group. The trough concentration of vancomycin was significantly higher in the PI group than in SII group (11.2 mg/L [5.9-13.7] vs. 7 mg/L [3.5- 9.3]; p = 0.02). The target attainment rate was higher in the PI group than in the SII group (59.4% and 19.3%, respectively; p = 0.001). There were no significant differences between the SII and PI groups regarding the peak concentrations of vancomycin, final creatinine and peak creatinine. There were no differences between the SII and PI groups regarding the failure events, PICU stay and duration of vancomycin therapy. The multivariable analysis showed that PI was significantly associated with higher trough serum concentrations of vancomycin (OR = 2.27; p = 0.005). Conclusion: Compared to the SII strategy, the PI strategy may be an optimized option to children with severe infection, as it can achieve higher trough concentrations and target concentration attainment.