DMPK perspective on quantitative model analysis for chimeric antigen receptor cell therapy: Advances and challenges.

Chimeric antigen receptor (CAR) cells are genetically engineered immune cells that specifically target tumor-associated antigens and have revolutionized cancer treatment, particularly in hematological malignancies, with ongoing investigations into their potential applications in solid tumors. This review provides a comprehensive overview of the current status and challenges in drug metabolism and pharmacokinetics (DMPK) for CAR cell therapy, specifically emphasizing on quantitative modeling and simulation (M&S). Furthermore, the recent advances in quantitative model analysis have been reviewed, ranging from clinical data characterization to mechanism-based modeling that connects in vitro and in vivo nonclinical and clinical study data. Additionally, the future perspectives and areas for improvement in CAR cell therapy translation have been reviewed. This includes using formulation quality considerations, characterization of appropriate animal models, refinement of in vitro models for bottom-up approaches, and enhancement of quantitative bioanalytical methodology. Addressing these challenges within a DMPK framework is pivotal in facilitating the translation of CAR cell therapy, ultimately enhancing the patients' lives through efficient CAR cell therapies.

Impact of Antibiotics Used for Acute Aspiration Bronchitis on the Prevention of Pneumonia.

BACKGROUNDS: It remains unclear if antibiotics should be used for the treatment of acute aspiration bronchitis to prevent the development of pneumonia. This study aimed to assess the associations between the use of antibiotics and the development of pneumonia among patients with acute aspiration bronchitis. METHODS: We retrospectively reviewed consecutive patients with acute aspiration bronchitis aged ≥75 years. Acute aspiration bronchitis was defined as a condition with aspiration risk, high fever (body temperature, ≥37.5 °C), respiratory symptoms, and the absence of evidence of pneumonia. RESULTS: There was no significant difference in the incidence of pneumonia between patients treated with and without antibiotics for acute aspiration bronchitis (6/44, 14% vs. 31/143, 22%; p = 0.242). Lower estimated glomerular filtration rate (adjusted odds ratio, 0.956; 95% confidence interval, 0.920-0.993) was significantly associated with the development of pneumonia. CONCLUSIONS: Antibiotic administration should not be routinely recommended to prevent pneumonia following acute aspiration bronchitis, and patients with decreased renal function should be closely monitored. A randomized controlled trial is necessary to validate these results.

Factors associated with changes in activities of daily living from admission to discharge among older patients with pneumonia.

INTRODUCTION: It has not been fully elucidated that nutritional parameters affect the change of activities of daily living (ADL) during pneumonia treatment. This study assessed the impact of nutritional status, including erector spinae muscle (ESM) size on ADL changes from admission to discharge among older patients with community-acquired pneumonia (CAP). METHODS: We retrospectively included patients (age: ≥65 years) who were admitted to the hospital for CAP and underwent chest computed tomography (CT) on admission. ADL was evaluated using the Barthel index, and patients were divided into the maintained or improved ADL group and the declined ADL group from admission through discharge. The ESM cross-sectional area was measured on a single-slice CT image. Logistic regression models were applied for assessing factors associated with changes in ADL. RESULTS: A total of 523 patients hospitalized for CAP (median age 86 years) were evaluated. The declined group had significantly higher ADL levels on admission, a greater frequency of smoking history and malignancy, and a lower frequency of cerebrovascular disease and dementia. No significant difference in ESM size was observed between the groups. Multivariate analysis revealed that higher ADL levels on admission (odds ratio 1.034, interquartile range 1.026-1.043) and malignancy (3.002, 1.150-7.836) were associated with a decline in ADL, whereas cerebrovascular disease (0.579, 0.373-0.900) was related to improvement or maintenance of ADL. CONCLUSIONS: Although nutritional status might not affect the change of ADL among older patients hospitalized with pneumonia, a cerebrovascular disease history may be a good predictor for ADL improvement.

Advanced translational PBPK model for transferrin receptor-mediated drug delivery to the brain.

Transferrin receptor (TfR)-mediated transcytosis is an attractive pathway for delivering large-molecule therapeutics to the central nervous system across the blood-brain barrier. Despite the clinical success of some drugs conjugated with TfR-binder, the desired drug profile for efficient TfR-mediated delivery to the targeted compartment within the brain, especially considering the species-related differences, has not been fully elucidated. To provide a prospective direction in the TfR-mediated drug delivery system, we developed an advanced physiologically based pharmacokinetic (PBPK) model. The model addresses TfR-mediated trans- and intracellular disposition of anti-TfR antibodies from brain capillary blood, endothelial cells, extracellular fluid (ECF), and eventually to brain parenchymal cells (BPCs), which correspond to pharmacological target sites of interest. The PBPK model is applicable in rats, monkeys, and human TfR knock-in (hTfR-KI) mice with satisfactory prediction accuracy through model calibration using the brain and plasma PK data of anti-TfR monoclonal antibodies, including their fused protein, with diverse binding affinity to TfR (TfR-Kd). The sensitivity analysis to determine drug properties required for the optimal brain delivery revealed 1) a bell-shaped relationship between TfR-Kd and brain exposure; 2) a minimum species difference between monkeys and hTfR-KI mice in the optimal TfR-Kd range, but not with rats; 3) a low TfR-Kd range to be preferably targeted for BPCs compared with ECF; and 4) an increase in brain exposure when using the pH-sensitive antibody. This may advance model-informed drug development, improve molecular design optimization, and provide precise human dose projection of drugs leveraging TfR-mediated shuttle technology into the brain.

Quantitative Model Analysis and Simulation of Pharmacokinetics and Metastasis-Associated Lung Adenocarcinoma 1 RNA Knockdown Effect After Systemic Administration of Cholesterol-Conjugated DNA/RNA Heteroduplex Oligonucleotide Crossing Blood-Brain Barrier of Mice.

The cholesterol-conjugated heteroduplex oligonucleotide (Chol-HDO) is a double-stranded complex; it comprises an antisense oligonucleotide (ASO) and its complementary strand with a cholesterol ligand. Chol-HDO is a powerful tool for achieving target RNA knockdown in the brains of mice after systemic injection. Here, a quantitative model analysis was conducted to characterize the relationship between the pharmacokinetics (PK) and pharmacodynamics (PD), non-coding RNA metastasis-associated lung adenocarcinoma 1 (Malat1) RNA, of Chol-HDO, in a time-dependent manner. The established PK model could describe regional differences in the observed brain concentration-time profiles. Incorporating the PD model enabled the unique knockdown profiles in the brain to be explained in terms of the time delay after single dosing and enhancement following repeated dosing. Moreover, sensitivity analysis of PK exposure/persistency, target RNA turnover, and knockdown potency identified key factors for the efficient and sustained target RNA knockdown in the brain. The simulation of an adequate dosing regimen quantitatively supported the benefit of Chol-HDO in terms of achieving a suitable dosing interval. This was achieved via sufficient and sustained brain exposure and subsequent strong and sustained target RNA knockdown in the brain, even after systemic injection. The present study provides new insights into drug discoveries and development strategies for HDO in patients with neurogenic disorders. SIGNIFICANCE STATEMENT: The quantitative model analysis presented here characterized the PK/PD relationship of Chol-HDO, enabled its simulation under various conditions or assumptions, and identified key factors for efficient and sustained RNA knockdown, such as PK exposure and persistency. Chol-HDO appears to be an efficient drug delivery system for the systemic administration of desired drugs to brain targets.

Biodistribution and delivery of oligonucleotide therapeutics to the central nervous system: Advances, challenges, and future perspectives.

Considerable advances have been made in the research and development of oligonucleotide therapeutics (OTs) for treating central nervous system (CNS) diseases, such as psychiatric and neurodegenerative disorders, because of their promising mode of action. However, due to the tight barrier function and complex physiological structure of the CNS, the efficient delivery of OTs to target the brain has been a major challenge, and intensive efforts have been made to overcome this limitation. In this review, we summarize the representative methodologies and current knowledge of biodistribution, along with the pharmacokinetic/pharmacodynamic (PK/PD) relationship of OTs in the CNS, which are critical elements for the successful development of OTs for CNS diseases. First, quantitative bioanalysis methods and imaging-based approaches for the evaluation of OT biodistribution are summarized. Next, information available on the biodistribution profile, distribution pathways, quantitative PK/PD modeling, and simulation of OTs following intrathecal or intracerebroventricular administration are reviewed. Finally, the latest knowledge on the drug delivery systems to the brain via intranasal or systemic administration as noninvasive routes for improved patient quality of life is reviewed. The aim of this review is to enrich research on the successful development of OTs by clarifying OT distribution profiles and pathways to the target brain regions or cells, and by identifying points that need further investigation for a mechanistic approach to generate efficient OTs.

Impact of Pseudomonas aeruginosa coverage on the prognosis of elderly patients with community-acquired pneumonia.

BACKGROUND: Although the 2019 American Thoracic Society and Infectious Diseases Society of America guidelines for community-acquired pneumonia (CAP) recommend the use of antibiotics with Pseudomonas aeruginosa coverage for patients with prior sputum isolation of P. aeruginosa, further research is needed to confirm its clinical outcomes. This study aimed to assess the impact of the use of antibiotics with P. aeruginosa coverage on mortality in elderly CAP patients with sputum isolation of P. aeruginosa. METHODS: We retrospectively included consecutive elderly patients who were hospitalized for CAP and P. aeruginosa-positive sputum culture. The association between the use of antibiotics with P. aeruginosa coverage and 28-day mortality was assessed based on propensity score to reduce selection bias. RESULTS: A total of 216 patients were included, and 68 (31%) of them were treated with antibiotics with P. aeruginosa coverage. The number of patients treated with antibiotics with P. aeruginosa coverage was significantly higher among nonsurvivors than among survivors. After adjustment using propensity score, the association between the use of antibiotics with P. aeruginosa coverage and the 28-day mortality was found to be statistically nonsignificant (odds ratio 2.182, 95% confidence interval 0.732-6.508, p = 0.162). CONCLUSIONS: The use of antibiotics with P. aeruginosa coverage in elderly CAP patients with sputum isolation of P. aeruginosa did not improve their prognosis. A randomized control study is required to identify cases that should be treated with antibiotics covering P. aeruginosa.

Radiological patterns and prognosis in elderly patients with acute Klebsiella pneumoniae pneumonia: A retrospective study.

Although Klebsiella pneumoniae pneumonia is an insidious threat among the elderly, the role of radiological features has not been elucidated. We aimed to evaluate thin-section chest computed tomography (CT) features and assess its associations with disease prognosis in elderly patients with acute K. pneumoniae pneumonia. We retrospectively included elderly patients, admitted for acute K. pneumoniae pneumonia, and investigated thin-section CT findings to determine whether bronchopneumonia or lobar pneumonia was present. The association between the radiological pattern of pneumonia and in-hospital mortality was analyzed. Eighty-six patients with acute K. pneumoniae pneumonia were included, and among them, the bronchopneumonia pattern was observed in 70 (81%) patients. Twenty-five (29%) patients died in hospital, and they had a greater incidence of lobar pneumonia pattern (40% in nonsurvivors vs 10% in survivors; P = .008), low albumin level (2.7 g/dL, range, 1.6-3.8 in nonsurvivors vs 3.0 g/dL, range, 1.7-4.2 in survivors; P = .026) and higher levels of aspartate aminotransferase (30 U/L, range, 11-186 in nonsurvivors vs 23 U/L, range, 11-102 in survivors, P = .017) and C-reactive protein (8.0 mg/dL, range, 0.9-26.5 in nonsurvivors vs 4.7 mg/dL, range, 0.0-24.0 in survivors; P = .047) on admission. Multivariate analysis showed that lobar pneumonia pattern was independently associated with increased in-hospital mortality (adjusted hazard ratio, 3.906; 95% CI, 1.513-10.079; P = .005). In elderly patients with acute K. pneumoniae pneumonia, the lobar pneumonia pattern may be less commonly observed, and this pattern could relate to poor prognosis.

Factors associated with gravity-dependent distribution on chest CT in elderly patients with community-acquired pneumonia: a retrospective observational study.

Although lung involvement in aspiration pneumonia typically has a gravity-dependent distribution on chest images, which patient's conditions contribute to its radiological pattern has not been fully elucidated. This study was designed to determine the factors associated with the gravity-dependent distribution of community-acquired pneumonia (CAP) on chest computed tomography (CT). This retrospective study included elderly patients aged ≥ 65 years with CAP who underwent chest CT within 1 week before or after admission. The factors associated with lower lobe- and posterior-predominant distributions of ground glass opacity or airspace consolidation were determined. Of the 369 patients with CAP, 348 (94%) underwent chest CT. Multivariate analyses showed that impaired consciousness, a low Barthel index of activities of daily living, and high hemoglobin levels were associated with lower lobe-predominant distribution, while male sex and impaired consciousness were associated with posterior-predominant distribution. Cerebrovascular diseases were unrelated to these distributions. While male sex, impaired consciousness, high hemoglobin levels, low albumin levels, and the number of involved lobes were associated with in-hospital mortality, gravity-dependent distributions were not. Impaired consciousness might be the most significant predictor of aspiration pneumonia; however, the gravity-dependent distribution of this disease is unlikely to affect disease prognosis.

High-resolution computed tomography features associated with differentiation of tuberculosis among elderly patients with community-acquired pneumonia: a multi-institutional propensity-score matched study.

While high-resolution computed tomography (HRCT) is increasingly performed, its role in diagnosing pulmonary tuberculosis (TB) among elderly patients with community-acquired pneumonia (CAP) has not been fully elucidated. This study aimed to determine HRCT features that can differentiate pulmonary TB from non-TB CAP in elderly patients. This study included consecutive elderly patients (age > 65 years) admitted to two teaching hospitals for pulmonary TB or non-TB pneumonia who met the CAP criteria of the American Thoracic Society/Infectious Diseases Society of America guidelines. After propensity score matching for clinical background between patients with pulmonary TB and those with non-TB CAP, their HRCT features were compared. This study included 151 patients with pulmonary TB and 238 patients with non-TB CAP. The presence of centrilobular nodules, air bronchograms, and cavities and the absence of ground-glass opacities and bronchial wall thickening were significantly associated with pulmonary TB. The negative predictive values of centrilobular nodules, air bronchograms, and cavities for pulmonary TB were moderate (70.6%, 67.9%, and 63.0%, respectively), whereas the positive predictive value of cavities was high (96.6%). In elderly patients, although some HRCT features could differentiate pulmonary TB from non-TB CAP, no useful findings could rule out pulmonary TB with certainty.

Methicillin-resistant Staphylococcus aureus among elderly patients with community-acquired pneumonia.

INTRODUCTION: The 2019 American Thoracic Society/Infectious Diseases Society of America guidelines for community-acquired pneumonia (CAP) recommend methicillin-resistant Staphylococcus aureus (MRSA) coverage for patients with prior sputum isolation of MRSA. This study aimed to determine the impact of MRSA coverage on in-hospital mortality in elderly patients with CAP among whom MRSA was isolated. METHODS: Consecutive elderly patients who were admitted for CAP and had positive sputum culture for MRSA were retrospectively included, and the association between MRSA coverage and in-hospital mortality was analyzed. RESULTS: Twenty (18%) of 111 patients received MRSA coverage. Although patients who received MRSA coverage tended to have more frequent prior isolation of MRSA compared to those who did not, no significant difference in in-hospital mortality was observed between both groups (2/20, 10% vs. 8/91, 9%). MRSA coverage was not associated with in-hospital mortality (odds ratio: 1.15; 95% CI: 0.23-5.89, p = 0.864); however, advanced age, hemoglobin level, a high A-DROP score, and C-reactive protein levels were associated with in-hospital mortality. MRSA coverage may not improve the prognosis of elderly patients with CAP who had positive sputum culture for MRSA. CONCLUSIONS: A randomized control study is required to determine the efficacy of MRSA coverage on the management of CAP in elderly patients.

Discovery of phenylpyrrolidine derivatives as a novel class of retinol binding protein 4 (RBP4) reducers.

Retinol-binding protein 4 (RBP4) is a potential drug target for metabolic and ophthalmologic diseases. A high-throughput screening of our compound library has identified a small-molecule RBP4 reducer 7a, as a hit compound. Aiming to provide a suitable tool for investigating the pharmacological effects of RBP4 reducers, we conducted a structure-activity relationship study of 7a. Exploration of the aryl head, oxazole core, and propanoic acid tail of 7a resulted in the discovery of novel, potent, and orally available phenylpyrrolidine derivatives 43b and 43c. Compound 43b had a potent and long-lasting blood RBP4-level-reducing effect when orally administered to mice at a dose as low as 0.3 mg/kg.

Quantitative PCR methodology with a volume-based unit for the sophisticated cellular kinetic evaluation of chimeric antigen receptor T cells.

Although the cellular kinetics of chimeric antigen receptor T (CAR T) cells are expressed in units of copies/µg gDNA, this notation carries the risk of misrepresentation owing to dramatic changes in blood gDNA levels after lymphocyte-depleting chemotherapy and rapid expansion of CAR T cells. Therefore, we aimed to establish a novel qPCR methodology incorporating a spike-in calibration curve that expresses cellular kinetics in units of copies/µL blood, as is the case for conventional pharmacokinetic studies of small molecules and other biologics. Dog gDNA was used as an external control gene. Our methodology enables more accurate evaluation of in vivo CAR T-cell expansion than the conventional approach; the unit "copies/µL blood" is therefore more appropriate for evaluating cellular kinetics than the unit "copies/µg gDNA." The results of the present study provide new insights into the relationship between cellular kinetics and treatment efficacy, thereby greatly benefiting patients undergoing CAR T-cell therapy.

Efficacy and safety of fluoroquinolone-containing regimens in treating pulmonary Mycobacterium avium complex disease: A propensity score analysis.

BACKGROUND: Although combination therapy using clarithromycin, rifampicin, and ethambutol is recommended for patients with pulmonary Mycobacterium avium complex (MAC) disease, some patients do not tolerate it because of adverse effects or underlying diseases. The efficacy and safety of fluoroquinolone-containing combination regimens as an alternative remain uncertain. This study aimed to compare the efficacy and safety of fluoroquinolone-containing regimens with those of the standard regimens for treating pulmonary MAC disease. METHODS: We retrospectively included consecutive MAC patients who were treated in our hospital between January 2011 and May 2019. Patients treated with fluoroquinolone-containing regimens who had relapsed after treatment with standard regimens were excluded. A propensity score analysis was conducted to reduce selection bias, and the proportions of clinical improvement, defined by chest imaging findings and sputum conversion, were compared between the fluoroquinolone-containing regimen and standard regimen groups. RESULTS: We analyzed 28 patients who received fluoroquinolone-containing regimens and 46 who received the standard regimen. Fluoroquinolone-containing regimens were more likely selected for patients with cavitary lesions, diabetes mellitus, culture negativity, a low daily physical activity level, a decreased lymphocyte count and an increased CRP level. The propensity score was calculated using these variables (C-statistic of the area under the receiver operating characteristic curve of the propensity score: 0.807, p < 0.0001). The fluoroquinolone-containing regimens were significantly inferior to the standard regimen in clinical improvements (p = 0.002, Log-rank test) in the univariate analysis, but the significance was lost after adjusting for the propensity score (HR 0.553, 95% CI 0.285-1.074, p = 0.080). Six (21%) patients in the fluoroquinolone-containing regimen group and ten (22%) patients in the standard regimen group experienced low-grade adverse effects. CONCLUSIONS: There was no significant difference in clinical improvement between these regimens after propensity score adjustment. A large-scale prospective study is required to validate these results.

Diffuse Large B-Cell Lymphoma Arising from the Lesion of Chronic Lobar Atelectasis.

Pulmonary lymphoma is rare, accounting for < 1% of primary lung cancers. Most primary pulmonary lymphomas (PPL) are low-grade mucosa-associated lymphoid tissue (MALT)-type, and among PPL, diffuse large B-cell lymphoma (DLBCL) is extremely rare. In contrast, there has been an increase in the incidence of DLBCL among patients with autoimmune disorders and recurrent or chronic bacterial infection. A subset of DLBCL has been reported to develop through transformation of preexisting or concurrent MALT. The respiratory symptoms are non-specific, and the chest X-ray findings demonstrate the presence of interstitial and mixed alveolar infiltrates, nodular lesions, and localized homogeneous consolidations; the diagnosis of pulmonary DLBCL is thus challenging and often leads to a misdiagnosis or delayed diagnosis. We herein report a case of DLBCL which was assumed to have arisen from the lesion of chronic atelectasis that was successfully diagnosed by endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA). A 74-year-old woman with diffuse bronchiectasis and chronic atelectasis of the left lower lobe suffered from productive cough and high fever. Increased airway filling with mucoid secretion was repeatedly observed within the area of atelectasis with bronchiectasis, and left lower lobe atelectasis developed. Subsequently, the hilar and mediastinal lymph nodes gradually became enlarged, and DLBCL was pathologically confirmed. In the present case, DLBCL was considered to have arisen in the lesion of chronic atelectasis. Physicians should recognize that DLBCL may develop at the site of chronic atelectasis during disease course of diffuse bronchiectasis, and thus DLBCL may be misdiagnosed as superimposed infection of chronic atelectasis.

Development of a bioanalytical method for circulating human T cells in animals using Arthrobacter luteus-based quantitative polymerase chain reaction and its application in preclinical biodistribution studies.

INTRODUCTION: In the development of cell therapy products for human use, studies on the biodistribution of transplanted cells in animals are important for assessing the safety and efficacy of these products. Although a few reports have described the biodistribution of human cells in animals using Arthrobacter luteus-based-polymerase chain reaction (Alu-PCR), most have used genomic DNA or synthetic oligonucleotide as calibrators, as opposed to actual cells. In addition, bioanalytical variability in the quantification of cells with respect to specificity, selectivity, accuracy, and precision, has not been evaluated. Accordingly, in this study, we validated the utility of this bioanalytical method for human T cells in mice to establish assay performance using cells as a calibrator. METHODS: A standard curve was constructed for the addition of cell lysates to mouse tissues and blood, and DNA was extracted. Alu-PCR was applied for the quantification of human peripheral blood CD8+ T cells in mice. To determine assay performance, we evaluated accuracy, precision, selectivity, specificity, and stability. In vivo cell kinetics and biodistribution were investigated based on intravenous administration of human T cells to mice. RESULTS: Alu-PCR enabled us to specifically detect human T cells in mouse blood and tissues. The lower detection limit of Alu-PCR was 10 cells/15 mg tissue (7.5 mg for spleen and lung) or cells/50 µL blood. Given that PCR threshold cycle (Cq) values among mouse samples (blood, liver spleen, lung, heart, and kidney) show slight variation, calibration curves should be generated using the same tissue as used for the assay. Most coefficients of variation in the assay were within 30%. The cell kinetics of administered human T cells in mice were successfully evaluated using the established Alu-qPCR. CONCLUSIONS: The Alu-PCR technique developed in this study showed sufficient specificity and sensitivity in detecting human peripheral blood CD8+ T cells in mice. This technique, which targets the primate-specific Alu gene, is applicable for quantifying transplanted human cells in animals without the necessity of cell labeling. The data presented herein will be useful for standardizing bioanalytical approaches in biodistribution studies of cell therapy products.