Exploring the Cost Effectiveness of a Whole-Genome Sequencing-Based Biomarker for Treatment Selection in Patients with Advanced Lung Cancer Ineligible for Targeted Therapy

OBJECTIVE

We aimed to perform an early cost-effectiveness analysis of using a whole-genome sequencing-based tumor mutation burden (WGS-TMB), instead of programmed death-ligand 1 (PD-L1), for immunotherapy treatment selection in patients with non-squamous advanced/metastatic non-small cell lung cancer ineligible for targeted therapy, from a Dutch healthcare perspective.

METHODS

A decision-model simulating individual patients with metastatic non-small cell lung cancer was used to evaluate diagnostic strategies to select first-line immunotherapy only or the immunotherapy plus chemotherapy combination. Treatment was selected using PD-L1 [A, current practice], WGS-TMB [B], and both PD-L1 and WGS-TMB [C]. Strategies D, E, and F take into account a patient's disease burden, in addition to PD-L1, WGS-TMB, and both PD-L1 and WGS-TMB, respectively. Disease burden was defined as a fast-growing tumor, a high number of metastases, and/or weight loss. A threshold of 10 mutations per mega-base was used to classify patients into TMB-high and TMB-low groups. Outcomes were discounted quality-adjusted life-years (QALYs) and healthcare costs measured from the start of first-line treatment to death. Healthcare costs includes drug acquisition, follow-up costs, and molecular diagnostic tests (i.e., standard diagnostic techniques and/or WGS for strategies involving TMB). Results were reported using the net monetary benefit at a willingness-to-pay threshold of €80,000/QALY. Additional scenario and threshold analyses were performed.

RESULTS

Strategy B had the lowest QALYs (1.84) and lowest healthcare costs (€120,800). The highest QALYs and healthcare costs were 2.00 and €140,400 in strategy F. In the base-case analysis, strategy A was cost effective with the highest net monetary benefit (€27,300), followed by strategy B (€26,700). Strategy B was cost effective when the cost of WGS testing was decreased by at least 24% or when immunotherapy results in an additional 0.5 year of life gained or more for TMB high compared with TMB low. Strategies C and F, which combined TMB and PD-L1 had the highest net monetary benefit (≥ €76,900) when the cost of WGS testing, immunotherapy, and chemotherapy acquisition were simultaneously reduced by at least 47%, 39%, and 43%, respectively. Furthermore, strategy C resulted in the highest net monetary benefit (≥ €39,900) in a scenario where patients with both PD-L1 low and TMB low were treated with chemotherapy instead of immunotherapy plus chemotherapy.

CONCLUSIONS

The use of WGS-TMB is not cost effective compared to PD-L1 for immunotherapy treatment selection in non-squamous metastatic non-small cell lung cancer in the Netherlands. WGS-TMB could become cost effective provided there is a reduction in the cost of WGS testing or there is an increase in the predictive value of WGS-TMB for immunotherapy effectiveness. Alternatively, a combination strategy of PD-L1 testing with WGS-TMB would be cost effective if used to support the choice to withhold immunotherapy in patients with a low expected benefit of immunotherapy.

Systemic anticancer therapy for urothelial carcinoma: UK oncologists' perspective

Urothelial carcinoma (UC) is a common cancer associated with a poor prognosis in patients with advanced disease. Platinum-based chemotherapy has remained the cornerstone of systemic anticancer treatment for many years, and recent developments in the treatment landscape have improved outcomes. In this review, we provide an overview of systemic treatment for UC, including clinical data supporting the current standard of care at each point in the treatment pathway and author interpretations from a UK perspective. Neoadjuvant cisplatin-based chemotherapy is recommended for eligible patients with muscle-invasive bladder cancer and is preferable to adjuvant treatment. For first-line treatment of advanced UC, platinum-eligible patients should receive cisplatin- or carboplatin-based chemotherapy, followed by avelumab maintenance in those without disease progression. Among patients unable to receive platinum-based chemotherapy, immune checkpoint inhibitor (ICI) treatment is an option for those with programmed death ligand 1 (PD-L1)-positive tumours. Second-line or later treatment options depend on prior treatment, and enfortumab vedotin is preferred after prior ICI and chemotherapy, although availability varies between countries. Additional options include rechallenge with platinum-based chemotherapy, an ICI, or non-platinum-based chemotherapy. Areas of uncertainty include the optimal number of first-line chemotherapy cycles for advanced UC and the value of PD-L1 testing for UC.

Model-Based Dose Selection of Subcutaneous Nivolumab in Patients with Advanced Solid Tumors

The pharmacokinetics (PK) of intravenous (i.v.) nivolumab is well characterized. A subcutaneous (s.c.) nivolumab formulation with and without recombinant human hyaluronidase PH20 enzyme is being evaluated in CheckMate 8KX (NCT03656718). A model-based analysis was conducted to characterize the PK of nivolumab s.c. and predict systemic exposures after i.v. and s.c. administration to guide dosing regimen selection for nivolumab s.c. A prior i.v. model was modified to incorporate an s.c. extravascular compartment and estimate the absorption rate constant and bioavailability of nivolumab s.c. Serum concentration-time data from 82 patients treated with nivolumab s.c. 720, 960, or 1,200 mg were pooled with existing i.v. data from multiple studies for model development. Prediction-corrected visual predictive check (pcVPC) plots assessed the model's performance. Stochastic simulations were conducted to predict exposures for i.v. and s.c. administration. The data were described by a two-compartment model with time-varying clearance, zero-order infusion into the central compartment after i.v. dosing, and first-order absorption from the extravascular compartment after s.c. dosing. The pcVPC suggested that the model adequately described the observed nivolumab s.c. data. Predicted nivolumab exposures at 1,200 mg s.c. every 4 weeks (q4w) were higher than those at the approved dose of 3 mg/kg i.v. q2w and lower than those at the highest tested safe dose of 10 mg/kg i.v. q2w. Nivolumab PK is well-characterized using the combined s.c./i.v. population PK model. The model-based analysis facilitated a comprehensive benefit-risk assessment of nivolumab s.c. and informed selection of 1,200 mg s.c. q4w for phase III evaluation.

Cost-effectiveness of pembrolizumab for previously treated MSI-H/dMMR solid tumours in the UK

OBJECTIVES

Patients with previously treated microsatellite instability-high (MSI-H)/mismatch repair deficient (dMMR) tumours have limited chemotherapeutic treatment options. Pembrolizumab received approval from the EMA in 2022 for the treatment of colorectal, endometrial, gastric, small intestine, and biliary MSI-H/dMMR tumour types. This approval was supported by data from the KEYNOTE-164 and KEYNOTE-158 clinical trials. This study evaluated the cost-effectiveness of pembrolizumab compared with standard of care (SoC) for previously treated MSI-H/dMMR solid tumours in line with the approved EMA label from a UK healthcare payer perspective.

METHODS

A multi-tumour partitioned survival model was built consisting of pre-progression, progressed disease, and dead health states. Pembrolizumab survival outcomes were extrapolated using Bayesian hierarchical models (BHMs) fitted to pooled data from KEYNOTE-164 and KEYNOTE-158. Comparator outcomes were informed by published sources. Tumour sites were modelled independently and then combined, weighted by tumour site distribution. A SoC comparator was used to formulate the overall cost-effectiveness result with pembrolizumab as the intervention. SoC comprised a weighted average of the comparators by tumour site based on market share. Drug acquisition, administration, adverse events, monitoring, subsequent treatment, end-of-life costs, and testing costs were included. Sensitivity and scenario analyses were performed, including modelling pembrolizumab efficacy using standard parametric survival models.

RESULTS

Pembrolizumab, at list price, was associated with £129,469 in total costs, 8.30 LYs, and 3.88 QALYs across the pooled tumour sites. SoC was associated with £28,222 in total costs, 1.14 LYs, and 0.72 QALYs across the pooled tumour sites. This yields an incremental cost-effectiveness ratio (ICER) of £32,085 per QALY. Results were robust to sensitivity and scenario analyses.

CONCLUSIONS

This model demonstrates pembrolizumab provides a valuable new alternative therapy for UK patients with MSH-H/dMMR cancer at the cost of £32,085 per QALY, with confidential discounts anticipated to improve cost-effectiveness further.

Effect of age on the risk of immune-related adverse events in patients receiving immune checkpoint inhibitors

Identifying patients at increased risk of immune-related adverse events (irAEs) facilitates safe application of immune checkpoint inhibitors (ICIs). This retrospective study aimed to determine the effect of age on the risk of irAEs in patients receiving ICIs and to identify potential mechanisms underlying age-related irAE risk differences. We analyzed reports of FDA Adverse Event Reporting System from July 1, 2014, to September 30, 2021. The information component ratio (ICΔ) was used to compare the irAE risk between older adults (> 65 years) and younger adults (25-65 years), of which the 95% confidential interval lower limit (ICΔ025) exceeding zero indicated significantly increased risk. We found that older adults had a significantly higher overall irAE risk than younger adults (ICΔ025 0.38), which was observed in almost all organ systems. We further analyzed the correlation between age-related irAE risks and age-related transcriptional changes to identify potential genes and pathways underlying age-related irAE risk differences. We found that genes significantly correlated with ICΔ were enriched in processes including extracellular matrix organization, regulation of myeloid leukocyte mediated immunity, and regulation of c-Jun N-terminal kinase (JNK) cascade. In addition, single-cell RNA sequencing analysis confirmed that genes involved in collagen-containing extracellular matrix and JNK cascade were significantly upregulated in myeloid cells from ICI-associated colitis tissues compared with ICI-treated colon tissues without colitis. In conclusion, older adults receiving ICIs have higher irAE risks than younger adults. Upregulation of genes involved in JNK cascade and collagen-containing extracellular matrix in myeloid cells may contribute to increased irAE risks in older adults.

Role of Biomarkers in the Management of Immune-Checkpoint Inhibitor-Related Myocarditis

PURPOSE OF REVIEW

Immune checkpoint inhibitor (ICI)-related myocarditis poses a major clinical challenge given its non-specific presentation, rapid progression, and high mortality rate. Here, we review the role of blood-based biomarkers in the clinical management of patients with ICI-related myocarditis.

RECENT FINDINGS

Myocardial injury, its unique pattern, and the co-occurrence with myositis are defining features of ICI-related myocarditis. Non-cardiac biomarkers, specifically creatinine phosphokinase, precedes the symptomatic presentation and is highly sensitive for diagnosing ICI-related myocarditis, making them useful screening biomarkers. Combined elevations in cardiac troponins and non-cardiac biomarkers improve the confidence of an ICI myocarditis diagnosis. High troponin and creatinine phosphokinase levels are strongly associated with severe outcomes. We propose biomarker-based algorithms for the monitoring and diagnosis of ICI-related myocarditis. Biomarkers, such as cardiac troponins and creatine phosphokinase, can be used in combination in the monitoring, diagnosis, and prognostication of patients with ICI-related myocarditis.

Subsequent treatment for locally advanced non-small-cell lung cancer that progressed after definitive chemoradiotherapy and consolidation therapy with durvalumab: a multicenter retrospective analysis (TOPGAN 2021-02)

PURPOSE

For patients with locally advanced non-small-cell lung cancer (LA-NSCLC) that progressed after definitive chemoradiotherapy (CRT) and durvalumab consolidation therapy, no subsequent standard treatment exists. The type of treatment selected for each timing of disease progression and its efficacy have not been investigated.

METHODS

We retrospectively enrolled patients with LA-NSCLC or inoperable NSCLC that progressed after definitive CRT and durvalumab consolidation therapy at 15 Japanese institutions. Patients were classified into the following: Early Discontinuation group (disease progression within 6 months after durvalumab initiation), Late Discontinuation group (disease progression from 7 to 12 months after durvalumab initiation), and Accomplishment group (disease progression from 12 months after durvalumab initiation).

RESULTS

Altogether, 127 patients were analyzed, including 50 (39.4%), 42 (33.1%) and 35 (27.5%) patients from the Early Discontinuation, Late Discontinuation, and Accomplishment groups, respectively. Subsequent treatments were Platinum plus immune checkpoint inhibitors (ICI) in 18 (14.2%), ICI in 7 (5.5%), Platinum in 59 (46.4%), Non-Platinum in 35 (27.6%), and tyrosine kinase inhibitor in 8 (6.3%) patients. In the Early Discontinuation, Late Discontinuation, and Accomplishment groups, 4 (8.0%), 7 (16.7%), and 7 (20.0%) patients were receiving Platinum plus ICI; 21 (42.0%), 22 (52.4%), and 16 (45.7%) were receiving Platinum, and 20 (40.0%), 8 (19.0%), and 7 (20.0%) were receiving Non-Platinum, respectively. No significant difference in progression-free survival was observed in the timing of disease progression.

CONCLUSION

In patients with LA-NSCLC hat progressed after definitive CRT and durvalumab consolidation therapy, subsequent treatment may change depending on the timing of disease progression.

Antinuclear antibody (ANA) status predicts immune-related adverse events in liver cancer patients undergoing anti-PD-1 therapy

Immune-related adverse events (irAEs) clinically resemble autoimmune diseases, indicating autoantibodies could be potential biomarkers for the prediction of irAEs. This study aimed to assess the predictive value of peripheral blood antinuclear antibody (ANA) status for irAEs, considering the time and severity of irAEs, as well as treatment outcome in liver cancer patients administered anti-PD-1 therapy. Ninety-three patients with advanced primary liver cancer administered anti-PD-1 treatment were analyzed retrospectively. They were divided into the ANA positive (ANA+, titer ≥ 1:100) and negative (ANA-, titer < 1:100) groups. Development of irAEs, progression-free survival (PFS), and overall survival (OS) were assessed. Compared with ANA- patients, ANA+ cases were more prone to develop irAEs (43.3% vs. 19.2%, P = 0.031). With the increase of ANA titers, the frequency of irAEs increased. The time interval between anti-PD-1 therapy and the onset of irAEs was significantly shorter in ANA+ patients compared with the ANA- group (median, 1.7 months vs. 5.0 months, P = 0.022). Moreover, the time between anti-PD-1 therapy and irAE occurrence decreased with increasing ANA titer. In addition, PFS and OS were decreased in ANA+ patients compared with the ANA- group (median PFS, 2.8 months vs. 4.2 months, P = 0.043; median OS, 21.1 months vs. not reached, P = 0.041). IrAEs occur at higher frequency in ANA+ liver cancer patients undergoing anti-PD-1 therapy. ANA titer could help predict irAE development and treatment outcome in these patients.

Kinetic Analysis of Prostate-Specific Antigen Interaction with Monoclonal Antibodies for Development of a Magnetic Immunoassay Based on Nontransparent Fiber Structures

Prostate cancer is the second most common cancer diagnosed in men worldwide. Measuring the prostate-specific antigen (PSA) is regarded as essential during prostate cancer screening. Early diagnosis of this disease relapse after radical prostatectomy requires extremely sensitive methods. This research presents an approach to development of an ultrasensitive magnetic sandwich immunoassay, which demonstrates the limit of PSA detection in human serum of 19 pg/mL at a dynamic range exceeding 3.5 orders of concentration. Such attractive performance stems, inter alia, from the kinetic analysis of monoclonal antibodies (mAbs) against free PSA to select the mAbs exhibiting best kinetic characteristics and specificity. The analysis is carried out with a label-free multiplex spectral-correlation interferometry compatible with inexpensive single-use glass sensor chips. The high sensitivity of developed PSA immunoassay is due to electronic quantification of magnetic nanolabels functionalized by the selected mAbs and three-dimension porous filters used as an extended solid phase. The assay is promising for PSA monitoring after radical prostatectomy. The proposed versatile approach can be applied for the rational design of highly sensitive tests for detection of other analytes in many fields, including in vitro diagnostics, veterinary, food safety, etc.

Monoclonal Antibodies as Long-Acting Products: What Are We Learning From Human Immunodeficiency Virus (HIV) and Coronavirus Disease 2019 (COVID-19)?

Broadly neutralizing antibodies directed against human immunodeficiency virus (HIV) offer promise as long-acting agents for prevention and treatment of HIV. Progress and challenges are discussed. Lessons may be learned from the development of monoclonal antibodies to treat and prevent COVID-19.

Immunomodulatory role of metalloproteinase ADAM17 in tumor development

ADAM17 is a member of the a disintegrin and metalloproteinase (ADAM) family of transmembrane proteases involved in the shedding of some cell membrane proteins and regulating various signaling pathways. More than 90 substrates are regulated by ADAM17, some of which are closely relevant to tumor formation and development. Besides, ADAM17 is also responsible for immune regulation and its substrate-mediated signal transduction. Recently, ADAM17 has been considered as a major target for the treatment of tumors and yet its immunomodulatory roles and mechanisms remain unclear. In this paper, we summarized the recent understanding of structure and several regulatory roles of ADAM17. Importantly, we highlighted the immunomodulatory roles of ADAM17 in tumor development, as well as small molecule inhibitors and monoclonal antibodies targeting ADAM17.

Potent monoclonal antibodies neutralize Omicron sublineages and other SARS-CoV-2 variants

The emergence and global spread of the SARS-CoV-2 Omicron variants, which carry an unprecedented number of mutations, raise serious concerns due to the reduced efficacy of current vaccines and resistance to therapeutic antibodies. Here, we report the generation and characterization of two potent human monoclonal antibodies, NA8 and NE12, against the receptor-binding domain of the SARS-CoV-2 spike protein. NA8 interacts with a highly conserved region and has a breadth of neutralization with picomolar potency against the Beta variant and the Omicron BA.1 and BA.2 sublineages and nanomolar potency against BA.2.12.1 and BA.4. Combination of NA8 and NE12 retains potent neutralizing activity against the major SARS-CoV-2 variants of concern. Cryo-EM analysis provides the structural basis for the broad and complementary neutralizing activity of these two antibodies. We confirm the in vivo protective and therapeutic efficacies of NA8 and NE12 in the hamster model. These results show that broad and potent human antibodies can overcome the continuous immune escape of evolving SARS-CoV-2 variants.

Review of the Existing Translational Pharmacokinetics Modeling Approaches Specific to Monoclonal Antibodies (mAbs) to Support the First-In-Human (FIH) Dose Selection

The interest in therapeutic monoclonal antibodies (mAbs) has continuously growing in several diseases. However, their pharmacokinetics (PK) is complex due to their target-mediated drug disposition (TMDD) profiles which can induce a non-linear PK. This point is particularly challenging during the pre-clinical and translational development of a new mAb. This article reviews and describes the existing PK modeling approaches used to translate the mAbs PK from animal to human for intravenous (IV) and subcutaneous (SC) administration routes. Several approaches are presented, from the most empirical models to full physiologically based pharmacokinetic (PBPK) models, with a focus on the population PK methods (compartmental and minimal PBPK models). They include the translational approaches for the linear part of the PK and the TMDD mechanism of mAbs. The objective of this article is to provide an up-to-date overview and future perspectives of the translational PK approaches for mAbs during a model-informed drug development (MIDD), since the field of PK modeling has gained recently significant interest for guiding mAbs drug development.

Comparative effectiveness of neutralising monoclonal antibodies in high risk COVID-19 patients: a Bayesian network meta-analysis

The purpose of this work was to review and synthesise the evidence on the comparative effectiveness of neutralising monoclonal antibody (nMAB) therapies in individuals exposed to or infected with SARS-CoV-2 and at high risk of developing severe COVID-19. Outcomes of interest were mortality, healthcare utilisation, and safety. A rapid systematic review was undertaken to identify and synthesise relevant RCT evidence using a Bayesian Network Meta-Analysis. Relative treatment effects for individual nMABs (compared with placebo and one another) were estimated. Pooled effects for the nMAB class compared with placebo were estimated. Relative effects were combined with baseline natural history models to predict the expected risk reductions per 1000 patients treated. Eight articles investigating four nMABs (bamlanivimab, bamlanivimab/etesevimab, casirivimab/imdevimab, sotrovimab) were identified. All four therapies were associated with a statistically significant reduction in hospitalisation (70-80% reduction in relative risk; absolute reduction of 35-40 hospitalisations per 1000 patients). For mortality, ICU admission, and invasive ventilation, the risk was lower for all nMABs compared with placebo with moderate to high uncertainty due to small event numbers. Rates of serious AEs and infusion reactions were comparable between nMABs and placebo. Pairwise comparisons between nMABs were typically uncertain, with broadly comparable efficacy. In conclusion, nMABs are effective at reducing hospitalisation among infected individuals at high-risk of severe COVID-19, and are likely to reduce mortality, ICU admission, and invasive ventilation rates; the effect on these latter outcomes is more uncertain. Widespread vaccination and the emergence of nMAB-resistant variants make the generalisability of these results to current patient populations difficult.

Polysorbates versus Hydroxypropyl Beta-Cyclodextrin (HPβCD): Comparative Study on Excipient Stability and Stabilization Benefits on Monoclonal Antibodies

Polysorbates (PS 20 and PS 80) are the most widely used surfactants in biopharmaceutical formulations to protect proteins from denaturation, aggregation, and surface adsorption. To date, around 70% of marketed therapeutic antibodies contain either PS 20 or PS 80 in their formulations. However, polysorbates are chemically diverse mixtures, which are prone to degradation by oxidation and hydrolysis to produce peroxides and fatty acids, which, in turn, induce protein oxidation, aggregation, and insoluble particle formation. These will negatively impact protein quality and stability. Thus, polysorbate degradation has emerged as one of the major challenges in the development and commercialization of therapeutic protein products. KLEPTOSE^® HPβCD (hydroxypropyl beta-cyclodextrin), a new multifunctional excipient, has been shown to provide protein stabilization functions in biopharmaceutical downstream processes and in their final formulations. This study aims to evaluate HPβCD, a new molecule of its class, against polysorbates as a stabilizer in biologics formulations. In this study, the chemical stability of KLEPTOSE^® HPβCDs is compared with polysorbates (20 and 80) under various stress conditions. When subjected to heat stress, HPβCDs show little change in product recovery (90.7–100.7% recovery for different HPβCDs), while polysorbates 20 and 80 show significant degradation, with only 11.5% and 7.3% undegraded product remaining, respectively. When subjected to other chemical stressors, namely, autoclave, light, and oxidative stresses, HPβCD remains almost stable, while polysorbates show more severe degradation, with 95.5% to 98.8% remaining for polysorbate 20 and 85.5% to 97.4% remaining for polysorbate 80. Further, profiling characterization and degradation analysis reveal that chemical structures of HPβCDs remain intact, while polysorbates undergo significant hydrolytic degradation and oxidation. Lastly, the physicochemical stability of monoclonal antibodies in formulations is investigated. When subjected to light stress, adalimumab, as a model mAb, formulated in the presence of HPβCD, shows a significant decrease in protein aggregation, and superior monomer and total protein recovery compared to PS 80-containing formulations. HPβCD also reduces both agitation and thermal stress-induced protein aggregation and prevents subvisible particle formation compared to PS 80.

Efficacy and safety of PI3K/Akt/mTOR inhibitors combined with trastuzumab therapy for HER2-positive breast cancer: a meta-analysis

OBJECTIVE

Activation of the PI3K/AKT/mTOR pathway in patients with HER2-positive breast cancer is associated with acquired resistance to trastuzumab. This randomized controlled trial (RCTs) meta-analysis was designed to evaluate the clinical efficacy and safety of PI3K/Akt/mTOR inhibitors in combination with trastuzumab in HER2-positive breast cancer.

MATERIALS AND METHODS

We searched on Web of Knowledge, PubMed, Embase, Cochrane, CNKI, and ClinicalTrials.Gov for RCTs comparing PI3K/Akt/mTOR inhibitors plus trastuzumab vs. standard trastuzumab treatments. Pooled estimates of progression-free survival (PFS), pathologic complete response (pCR), and incidence of adverse events were determined.

RESULTS

5 studies out of 610 were found to be eligible and were included in our analysis (n=1,548 participants). PI3K/Akt/mTOR inhibitors combination with trastuzumab treatments resulted in a statistically significant increase in PFS compared with conventional trastuzumab therapy (HR 0.82; 95% CI: 0.76-0.90; p<0.00001). The new combination treatment was more effective on hormone receptor-negative patients (HR 0.73; 95% CI: 0.58-0.93; p=0.010). In addition, the combination of PI3K/Akt/mTOR inhibitors with trastuzumab slightly increased the risk of some adverse events, such as neutropenia, leukopenia, fatigue, and anemia.

CONCLUSIONS

The combination treatments of PI3K/Akt/mTOR inhibitors and trastuzumab for PI3K/Akt/mTOR inhibitors combined with trastuzumab treatments for patients with HER2-positive breast cancer can improve median progression-free survival while increasing the incidence of adverse events. It is still controversial based on the current evidence. Due to the limited number and quality of included studies, more high-quality studies are needed for further analysis.

Discovery of functionally distinct anti-C7 monoclonal antibodies and stratification of anti-nicotinic AChR positive Myasthenia Gravis patients

Myasthenia Gravis (MG) is mediated by autoantibodies against acetylcholine receptors that cause loss of the receptors in the neuromuscular junction. Eculizumab, a C5-inhibitor, is the only approved treatment for MG that mechanistically addresses complement-mediated loss of nicotinic acetylcholine receptors. It is an expensive drug and was approved despite missing the primary efficacy endpoint in the Phase 3 REGAIN study. There are two observations to highlight. Firstly, further C5 inhibitors are in clinical development, but other terminal pathway proteins, such as C7, have been relatively understudied as therapeutic targets, despite the potential for lower and less frequent dosing. Secondly, given the known heterogenous mechanisms of action of autoantibodies in MG, effective patient stratification in the REGAIN trial may have provided more favorable efficacy readouts. We investigated C7 as a target and assessed the in vitro function, binding epitopes and mechanism of action of three mAbs against C7. We found the mAbs were human, cynomolgus monkey and/or rat cross-reactive and each had a distinct, novel mechanism of C7 inhibition. TPP1820 was effective in preventing experimental MG in rats in both prophylactic and therapeutic dosing regimens. To enable identification of MG patients that are likely to respond to C7 inhibition, we developed a patient stratification assay and showed in a small cohort of MG patients (n=19) that 63% had significant complement activation and C7-dependent loss of AChRs in this in vitro set up. This study provides validation of C7 as a target for treatment of MG and provides a means of identifying patients likely to respond to anti-C7 therapy based on complement-activating properties of patient autoantibodies.

Autoantibody positivity predicts severity of rheumatic immune-related adverse events to immune-checkpoint inhibitors

OBJECTIVE

Immune-related adverse events (irAEs) due to immune checkpoint inhibitors are responsible for a considerable burden of morbidity and mortality. Predictors of severity of rheumatic irAEs have not been identified yet. The objective of this study was to test the hypothesis whether the presence of autoantibodies could be associated with a more severe and difficult-to-treat clinical phenotype of rheumatic irAEs.

METHODS

Patients referred to our centre due to the onset of rheumatic irAEs were prospectively recruited between June 2018 and December 2020. A pre-specified panel of autoantibodies was tested in each patient at baseline visit. All patients were started on glucocorticoids and then followed-up. Conventional or biologic immunosuppressants were started in case of steroid-refractory or relapsing disease. Logistic regression analysis was performed to evaluate the association between the baseline positivity of at least one autoantibody and the necessity of an add-on therapy.

RESULTS

Fourty-three patients with rheumatic irAEs were enrolled. Twenty-five (58%) patients had positivity of at least one of the tested autoantibodies. Twenty-two (51%) patients required the start of an additional immunosuppressant during follow-up. The only factor associated with the necessity of an add-on therapy was autoantibody positivity (OR=9.65, 95% CI:2.09-44.56; p-value 0.004).

CONCLUSIONS

The presence of autoantibodies in patients with cancer who develop rheumatic irAEs could predict their progression to difficult-to-treat clinical manifestations. This finding might prompt a future therapeutic approach based on a tailored and earlier immunosuppressive treatment in selected cases.

Monoclonal antibodies effectively potentiate complement activation and phagocytosis of Staphylococcus epidermidis in neonatal human plasma

Central line associated bloodstream infections (CLABSI) with Staphylococcus epidermidis are a major cause of morbidity in neonates, who have an increased risk of infection because of their immature immune system. As especially preterm neonates suffer from antibody deficiency, clinical studies into preventive therapies have thus far focused on antibody supplementation with pooled intravenous immunoglobulins from healthy donors (IVIG) but with little success. Here we study the potential of monoclonal antibodies (mAbs) against S. epidermidis to induce phagocytic killing by human neutrophils. Nine different mAbs recognizing Staphylococcal surface components were cloned and expressed as human IgG1s. In binding assays, clones rF1, CR5133 and CR6453 showed the strongest binding to S. epidermidis ATCC14990 and CR5133 and CR6453 bound the majority of clinical isolates from neonatal sepsis (19 out of 20). To study the immune-activating potential of rF1, CR5133 and CR6453, bacteria were opsonized with mAbs in the presence or absence of complement. We observed that activation of the complement system is essential to induce efficient phagocytosis of S. epidermidis. Complement activation and phagocytic killing could be enhanced by Fc-mutations that improve IgG1 hexamerization on cellular surfaces. Finally, we studied the ability of the mAbs to activate complement in r-Hirudin neonatal plasma conditions. We show that classical pathway complement activity in plasma isolated from neonatal cord blood is comparable to adult levels. Furthermore, mAbs could greatly enhance phagocytosis of S. epidermidis in neonatal plasma. Altogether, our findings provide insights that are crucial for optimizing anti-S. epidermidis mAbs as prophylactic agents for neonatal CLABSI.

Real-life data on monoclonal antibodies and antiviral drugs in Italian inborn errors of immunity patients during COVID-19 pandemic

Background

Since the beginning of the COVID-19 pandemic, patients with Inborn Errors of Immunity have been infected by SARS-CoV-2 virus showing a spectrum of disease ranging from asymptomatic to severe COVID-19. A fair number of patients did not respond adequately to SARS-CoV-2 vaccinations, thus early therapeutic or prophylactic measures were needed to prevent severe or fatal course or COVID-19 and to reduce the burden of hospitalizations.

Methods

Longitudinal, multicentric study on patients with Inborn Errors of Immunity immunized with mRNA vaccines treated with monoclonal antibodies and/or antiviral agents at the first infection and at reinfection by SARS-CoV-2. Analyses of efficacy were performed according to the different circulating SARS-CoV-2 strains.

Results

The analysis of the cohort of 192 SARS-CoV-2 infected patients, across 26 months, showed the efficacy of antivirals on the risk of hospitalization, while mabs offered a positive effect on hospitalization, and COVID-19 severity. This protection was consistent across the alpha, delta and early omicron waves, although the emergence of BA.2 reduced the effect of available mabs. Hospitalized patients treated with mabs and antivirals had a lower risk of ICU admission. We reported 16 re-infections with a length of SARS-CoV-2 positivity at second infection shorter among patients treated with mabs. Treatment with antivirals and mabs was safe.

Conclusions

The widespread use of specific therapy, vaccination and better access to care might have contributed to mitigate risk of mortality, hospital admission, and severe disease. However, the rapid spread of new viral strains underlines that mabs and antiviral beneficial effects should be re- evaluated over time.

Monoclonal antibodies targeting the influenza virus N6 neuraminidase

Influenza A viruses are a diverse species that include 16 true hemagglutinin (HA) subtypes and 9 true neuraminidase (NA) subtypes. While the antigenicity of many HA subtypes is reasonably well studied, less is known about NA antigenicity, especially when it comes to non-human subtypes that only circulate in animal reservoirs. The N6 subtype NAs are mostly found in viruses infecting birds. However, they have also been identified in viruses that infect mammals, such as swine and seals. More recently, highly pathogenic H5N6 subtype viruses have caused rare infections and mortality in humans. Here, we generated murine mAbs to the N6 NA, characterized their breadth and antiviral properties in vitro and in vivo and mapped their epitopes by generating escape mutant viruses. We found that the antibodies had broad reactivity across the American and Eurasian N6 lineages, but relatively little binding to the H5N6 NA. Several of the antibodies exhibited strong NA inhibition activity and some also showed activity in the antibody dependent cellular cytotoxicity reporter assay and neutralization assay. In addition, we generated escape mutant viruses for six monoclonal antibodies and found mutations on the lateral ridge of the NA. Lastly, we observed variable protection in H4N6 mouse challenge models when the antibodies were given prophylactically.

Comparison of originator and biosimilar monoclonal antibodies using HRMS, Fc affinity chromatography, and 2D-HPLC

Due to the complex manufacturing process of therapeutic monoclonal antibodies, it is hardly possible to produce an identical copy of the original product (originator). Consequently, follow-on products (biosimilars) must demonstrate their efficacy being similar to the originator in terms of structure and function. During this process, a variety of analytical methods are required for this purpose. This study focuses on three particularly relevant analytical techniques: high-resolution mass spectrometry, fragment crystallisable (Fc) affinity chromatography, and two-dimensional peptide mapping. Each analytical method proved able to identify specific differences between originator and biosimilar. High-resolution mass spectrometry was used to characterize the glycan pattern. It was shown that a trastuzumab biosimilar did not have the G0:G0F sugar modification identified in the originator. The application of affinity chromatography to rituximab showed that originator and biosimilar interacted differently with the immobilized Fc receptor. Furthermore, 2D-HPLC peptide mapping demonstrated the influence of orthogonality of separation dimensions, leading to differentiation of a rituximab originator and biosimilar.

A Broad-Based Characterization of a Cell-Penetrating, Single Domain Camelid Bi-Specific Antibody Monomer That Targets STAT3 and KRAS Dependent Cancers

STAT3 and KRAS regulate cell proliferation, survival, apoptosis, cell migration, and angiogenesis. Aberrant expression of STAT3 and mutant active forms of KRAS have been well-established in the induction and maintenance of multiple cancers. STAT3 and KRAS mutant proteins have been considered anti-cancer targets; however, they are also considered to be clinically “undruggable” intracellular molecules, except for KRAS(G12C). Here we report a first-in-class molecule, a novel, single domain camelid VHH antibody (15 kDa), SBT-100, that binds to both STAT3 and KRAS and can penetrate the tumor cell membrane, and significantly inhibit cancer cell growth. Additionally, SBT-100 inhibits KRAS GTPase activity and downstream phosphorylation of ERK in vitro. In addition, SBT-100 inhibits the growth of multiple human cancers in vitro and in vivo. These results demonstrate the feasibility of targeting hard-to-reach aberrant intracellular transcription factors and signaling proteins simultaneously with one VHH to improve cancer therapies.

SARS-CoV-2-neutralising monoclonal antibodies to prevent COVID-19

BACKGROUND

Monoclonal antibodies (mAbs) are laboratory-produced molecules derived from the B cells of an infected host. They are being investigated as potential prophylaxis to prevent coronavirus disease 2019 (COVID-19).

OBJECTIVES

To assess the effects of SARS-CoV-2-neutralising mAbs, including mAb fragments, to prevent infection with SARS-CoV-2 causing COVID-19; and to maintain the currency of the evidence, using a living systematic review approach.

SEARCH METHODS

We searched the Cochrane COVID-19 Study Register, MEDLINE, Embase, and three other databases on 27 April 2022. We checked references, searched citations, and contacted study authors to identify additional studies.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) that evaluated SARS-CoV-2-neutralising mAbs, including mAb fragments, alone or combined, versus an active comparator, placebo, or no intervention, for pre-exposure prophylaxis (PrEP) and postexposure prophylaxis (PEP) of COVID-19. We excluded studies of SARS-CoV-2-neutralising mAbs to treat COVID-19, as these are part of another review.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed search results, extracted data, and assessed risk of bias using Cochrane RoB 2. Prioritised outcomes were infection with SARS-CoV-2, development of clinical COVID-19 symptoms, all-cause mortality, admission to hospital, quality of life, adverse events (AEs), and serious adverse events (SAEs). We rated the certainty of evidence using GRADE.

MAIN RESULTS

We included four RCTs of 9749 participants who were previously uninfected and unvaccinated at baseline. Median age was 42 to 76 years. Around 20% to 77.5% of participants in the PrEP studies and 35% to 100% in the PEP studies had at least one risk factor for severe COVID-19. At baseline, 72.8% to 82.2% were SARS-CoV-2 antibody seronegative. We identified four ongoing studies, and two studies awaiting classification. Pre-exposure prophylaxis Tixagevimab/cilgavimab versus placebo One study evaluated tixagevimab/cilgavimab versus placebo in participants exposed to SARS-CoV-2 wild-type, Alpha, Beta, and Delta variant. About 39.3% of participants were censored for efficacy due to unblinding and 13.8% due to vaccination. Within six months, tixagevimab/cilgavimab probably decreases infection with SARS-CoV-2 (risk ratio (RR) 0.45, 95% confidence interval (CI) 0.29 to 0.70; 4685 participants; moderate-certainty evidence), decreases development of clinical COVID-19 symptoms (RR 0.18, 95% CI 0.09 to 0.35; 5172 participants; high-certainty evidence), and may decrease admission to hospital (RR 0.03, 95% CI 0 to 0.59; 5197 participants; low-certainty evidence). Tixagevimab/cilgavimab may result in little to no difference on mortality within six months, all-grade AEs, and SAEs (low-certainty evidence). Quality of life was not reported. Casirivimab/imdevimab versus placebo One study evaluated casirivimab/imdevimab versus placebo in participants who may have been exposed to SARS-CoV-2 wild-type, Alpha, and Delta variant. About 36.5% of participants opted for SARS-CoV-2 vaccination and had a mean of 66.1 days between last dose of intervention and vaccination. Within six months, casirivimab/imdevimab may decrease infection with SARS-CoV-2 (RR 0.01, 95% CI 0 to 0.14; 825 seronegative participants; low-certainty evidence) and may decrease development of clinical COVID-19 symptoms (RR 0.02, 95% CI 0 to 0.27; 969 participants; low-certainty evidence). We are uncertain whether casirivimab/imdevimab affects mortality regardless of the SARS-CoV-2 antibody serostatus. Casirivimab/imdevimab may increase all-grade AEs slightly (RR 1.14, 95% CI 0.98 to 1.31; 969 participants; low-certainty evidence). The evidence is very uncertain about the effects on grade 3 to 4 AEs and SAEs within six months. Admission to hospital and quality of life were not reported. Postexposure prophylaxis Bamlanivimab versus placebo One study evaluated bamlanivimab versus placebo in participants who may have been exposed to SARS-CoV-2 wild-type. Bamlanivimab probably decreases infection with SARS-CoV-2 versus placebo by day 29 (RR 0.76, 95% CI 0.59 to 0.98; 966 participants; moderate-certainty evidence), may result in little to no difference on all-cause mortality by day 60 (R 0.83, 95% CI 0.25 to 2.70; 966 participants; low-certainty evidence), may increase all-grade AEs by week eight (RR 1.12, 95% CI 0.86 to 1.46; 966 participants; low-certainty evidence), and may increase slightly SAEs (RR 1.46, 95% CI 0.73 to 2.91; 966 participants; low-certainty evidence). Development of clinical COVID-19 symptoms, admission to hospital within 30 days, and quality of life were not reported. Casirivimab/imdevimab versus placebo One study evaluated casirivimab/imdevimab versus placebo in participants who may have been exposed to SARS-CoV-2 wild-type, Alpha, and potentially, but less likely to Delta variant. Within 30 days, casirivimab/imdevimab decreases infection with SARS-CoV-2 (RR 0.34, 95% CI 0.23 to 0.48; 1505 participants; high-certainty evidence), development of clinical COVID-19 symptoms (broad-term definition) (RR 0.19, 95% CI 0.10 to 0.35; 1505 participants; high-certainty evidence), may result in little to no difference on mortality (RR 3.00, 95% CI 0.12 to 73.43; 1505 participants; low-certainty evidence), and may result in little to no difference in admission to hospital. Casirivimab/imdevimab may slightly decrease grade 3 to 4 AEs (RR 0.50, 95% CI 0.24 to 1.02; 2617 participants; low-certainty evidence), decreases all-grade AEs (RR 0.70, 95% CI 0.61 to 0.80; 2617 participants; high-certainty evidence), and may result in little to no difference on SAEs in participants regardless of SARS-CoV-2 antibody serostatus. Quality of life was not reported.

AUTHORS' CONCLUSIONS

For PrEP, there is a decrease in development of clinical COVID-19 symptoms (high certainty), infection with SARS-CoV-2 (moderate certainty), and admission to hospital (low certainty) with tixagevimab/cilgavimab. There is low certainty of a decrease in infection with SARS-CoV-2, and development of clinical COVID-19 symptoms; and a higher rate for all-grade AEs with casirivimab/imdevimab. For PEP, there is moderate certainty of a decrease in infection with SARS-CoV-2 and low certainty for a higher rate for all-grade AEs with bamlanivimab. There is high certainty of a decrease in infection with SARS-CoV-2, development of clinical COVID-19 symptoms, and a higher rate for all-grade AEs with casirivimab/imdevimab.   Although there is high-to-moderate certainty evidence for some outcomes, it is insufficient to draw meaningful conclusions. These findings only apply to people unvaccinated against COVID-19. They are only applicable to the variants prevailing during the study and not other variants (e.g. Omicron). In vitro, tixagevimab/cilgavimab is effective against Omicron, but there are no clinical data. Bamlanivimab and casirivimab/imdevimab are ineffective against Omicron in vitro. Further studies are needed and publication of four ongoing studies may resolve the uncertainties.

Immunogenicity of Monoclonal Antibodies and the Potential Use of HLA Haplotypes to Predict Vulnerable Patients

The use of monoclonal antibodies (mAbs) in the clinic has successfully expanded to treatment of cancer, viral infections, inflammations, and other indications. However, some of the classes of mAbs that are used in the clinic show the formation of anti-drug antibodies (ADAs) leading to loss of efficacy. This review describes ADA formation for the various mAbs, and its clinical effect. Lastly, this review considers the use of HLA-haplotypes as biomarkers to predict vulnerability of patients sensitive to formation of ADAs.

[Preliminary Study on Screening and Identification of Lewis a Antigen Mimic Epitope in Alpaca Phage Display Nanobody Library]

OBJECTIVE

To establish a new method for synthesizing Lewis blood group antigens, that is, the mimotopes of Lewis blood group antigens were screened by using an alpaca phage display nanobody library.

METHODS

We selected mimotopes of the Lewis a (le^a) antigen by affinity panning of an alpaca phage display nanobody library using a monoclonal anti-le^a antibody. Enzyme-linked immunosorbent assay (ELISA) was used to test the affinity of the positive clones for the monoclonal anti-le^a antibody, and the high-affinity positive clones were selected for sequencing and synthesis. Finally, the sensitivity, specificity and reactivity of the synthesized le^a mimotope in clinical samples were verified by ELISA.

RESULTS

A total of 96 phage clones were randomly selected, and 24 were positive. Fourteen positive clones with the highest affinity were selected for sequencing. The result showed that there were 5 different sequences, among which 3 sequences with the highest frequency, largest difference and highest affinity were selected for expression and synthesis. The sensitivity and specificity of le^a mimic antigen by ELISA showed that, the minimum detection limit of gel microcolumn assay (GMA) and ELISA method were 25 times different, and the le^a mimic antigen had no cross reacted with the other five unrelated monoclonal antibodies(P<0.001). Finally, 30 clinical plasma samples were analyzed. The mean absorbance of the 15 positive plasma samples was significantly higher than that of the 15 negative plasma samples (P=0.02). However, the positive signal values of the clinical samples were much lower than those of the monoclonal antibodies.

CONCLUSION

A new method of screening le^a mimic antigen by using alpaca phage nanoantibody library has been established, which is expected to realize the screening of le^a mimotopes, thus realizing the application of high-sensitivity detection methods such as ELISA and chemiluminescence in blood group antibody identification.

Managing antibody stability: effects of stressors on Ipilimumab from the commercial formulation to diluted solutions

The stability of the monoclonal antibody Ipilimumab, the active ingredient of Yervoy®, used for the treatment of different types of cancer, has been investigated. Shaking/temperature, light exposure and dilution, protein drug renowned stressors, were applied on a 30-45-day series of experiments to observe the physicochemical and biological behavior of the molecule. Ipilimumab demonstrated stability under shaking and heat up to 45 days, without any unfolding during the induced combined stressors. Under artificial sunlight, the mAb showed to be sensitive even under the minimum dose tested (720 kJ/m²) with formation of aggregates, particularly when diluted in glucose solution. The light-induced soluble aggregates were higher in the case of diluted samples irradiated with much higher light doses (10460 kJ/m²). The aggregation of Ipilimumab took place also by irradiating the non-diluted formulation, indicating that the excipients did not protect completely the drug from photodegradation. Amino acid oxidation and deamidation were found. Anyway, after irradiation with both light doses, soluble Ipilimumab maintained its typical β-sheets structure, and the tertiary structure was nearly maintained compared to the dark. As an additional stressor test, the effect of dilution on the formulation was monitored by using a saline solution (1 mg/mL Ipilimumab) applied during hospital infusion. After two days from dilution, the protein exhibited aggregation and chemical modifications including oxidation and deamidation. When stability conditions were compromised, the viability of human cell lines treated with the stressed formulation slight decreased suggesting low potential biological toxicity of the modified mAb. As this study has demonstrated the susceptibility of Ipilimumab to light, specific solutions, and excipients as well as the use of safe light in manufacturing, handling, and storage of this drug should be promoted. Moreover, the use of proper primary and secondary packaging should be indicated to avoid the detrimental effect of light on the mAb structure and efficacy. A detailed understanding of Ipilimumab physicochemical properties, integrity, and stability could assure the best storage and manipulation conditions for its safe and successful application in cancer therapy.

Development and characterization of rabbit monoclonal antibodies that recognize human spermine oxidase and application to immunohistochemistry of human cancer tissues

The enzyme spermine oxidase (SMOX) is involved in polyamine catabolism and converts spermine to spermidine. The enzymatic reaction generates reactive hydrogen peroxide and aldehydes as by-products that can damage DNA and other biomolecules. Increased expression of SMOX is frequently found in lung, prostate, colon, stomach and liver cancer models, and the enzyme also appears to play a role in neuronal dysfunction and vascular retinopathy. Because of growing evidence that links SMOX activity with DNA damage, inflammation, and carcinogenesis, the enzyme has come into view as a potential drug target. A major challenge in cancer research is the lack of characterization of antibodies used for identification of target proteins. To overcome this limitation, we generated a panel of high-affinity rabbit monoclonal antibodies against various SMOX epitopes and selected antibodies for use in immunoblotting, SMOX quantification assays, immunofluorescence microscopy and immunohistochemistry. Immunohistochemistry analysis with the antibody SMAB10 in normal and transformed tissues confirms that SMOX is upregulated in several different cancers. Together, the panel of antibodies generated herein adds to the toolbox of high-quality reagents to study SMOX biology and to facilitate SMOX drug development.

Emulation of a Target Trial From Observational Data to Compare Effectiveness of Casirivimab/Imdevimab and Bamlanivimab/Etesevimab for Early Treatment of Non-Hospitalized Patients With COVID-19

Objectives

Comparative analysis between different monoclonal antibodies (mAbs) against SARS-CoV-2 are lacking. We present an emulation trial from observational data to compare effectiveness of Bamlanivimab/Etesevimab (BAM/ETE) and Casirivimab/Imdevimab (CAS/IMD) in outpatients with early mild-to-moderate COVID-19 in a real-world scenario of variants of concern (VoCs) from Alpha to Delta.

Methods

Allocation to treatment was subject to mAbs availability, and the measured factors were not used to determine which combination to use. Patients were followed through day 30. Viral load was measured by cycle threshold (CT) on D1 (baseline) and D7.Primary outcome was time to COVID-19-related hospitalization or death from any cause over days 0-30. Weighted pooled logistic regression and marginal structural Cox model by inverse probability weights were used to compare BAM/ETE vs. CAS/IMD. ANCOVA was used to compare mean D7 CT values by intervention. Models were adjusted for calendar month, MASS score and VoCs. We evaluated effect measure modification by VoCs, vaccination, D1 CT levels and enrolment period.

Results

COVID19-related hospitalization or death from any cause occurred in 15 of 237 patients in the BAM/ETE group (6.3%) and in 4 of 196 patients in the CAS/IMD group (2.0%) (relative risk reduction [1 minus the relative risk] 72%; p=0.024). Subset analysis carried no evidence that the effect of the intervention was different across stratification factors. There was no evidence in viral load reduction from baseline through day 7 across the two groups (+0.17, 95% -1.41;+1.74, p=0.83). Among patients who experienced primary outcome, none showed a negative RT-PCR test in nasopharyngeal swab (p=0.009) and 82.4% showed still high viral load (p<0.001) on D7.

Conclusions

In a pre-Omicron epidemiologic scenario, CAS/IMD reduced risk of clinical progression of COVID-19 compared to BAM/ETE. This effect was not associated with a concomitant difference in virological response.

Cost-effectiveness of pembrolizumab for second-line treatment of esophageal squamous cell carcinoma patients with a combined positive score of 10 or more

Aim: This study aimed to evaluate the cost-effectiveness of pembrolizumab compared with that of chemotherapy in the second-line treatment of locally advanced or metastatic esophageal squamous cell carcinoma (ESCC) patients with a combined positive score ≥10. Methods: A Markov model was established to compare the lifetime costs and quality-adjusted life years (QALYs) of different treatment options. Sensitivity analysis was performed to test the stability of the model. Results: The increased utility and cost of pembrolizumab were 0.442 QALYs and US$11,826.79 compared with those of chemotherapy. The incremental cost-effectiveness ratio was US$26,757.45/QALY, which was less than the threshold of three-times the GDP per capita. The prices of paclitaxel and pembrolizumab were the most important influencing factors. Conclusion: Pembrolizumab is a cost-effective second-line treatment of ESCC.

Estimated Health Outcomes and Costs of COVID-19 Prophylaxis With Monoclonal Antibodies Among Unvaccinated Household Contacts in the US

IMPORTANCE

The COVID-19 pandemic has led to more than 900 000 deaths in the US and continues to disrupt lives even as effective vaccines are available.

OBJECTIVE

To estimate the health outcomes and net cost of implementing postexposure prophylaxis (PEP) with monoclonal antibodies (mAbs) against household exposure to COVID-19.

DESIGN, SETTING, AND PARTICIPANTS

This study is a decision analytical model of results from a randomized clinical trial of casirivimab with imdevimab administered as subcutaneous injections to unvaccinated, SARS-CoV-2-negative household contacts of people with confirmed COVID-19 with complementary data on household demographic structure, vaccine coverage, and confirmed COVID-19 case counts. The study used US data from May 2021 for a simulated population of US individuals of all ages within low-transmission or high-transmission scenarios.

EXPOSURES

Age, sex, race, ethnicity, and COVID-19 vaccination status.

MAIN OUTCOME OR MEASURES

Symptomatic infection, hospitalization, death, and net payer cost of monoclonal antibody PEP for COVID-19.

RESULTS

In a month of transmission intensity similar to that of May 2021, a mAb PEP program reaching 50% of exposed, unvaccinated household members aged 50 years and older was estimated to avert 1820 symptomatic infections (95% uncertainty interval [UI], 1220-2454 symptomatic infections), 528 hospitalizations (95% UI, 354-724 hospitalizations), and 84 deaths (95% UI, 55-116 deaths) in a low-transmission scenario and 4834 symptomatic infections (95% UI, 3375-6257 symptomatic infections), 1404 hospitalizations (95% UI, 974-1827 hospitalizations), and 223 deaths (95% UI, 152-299 deaths) in a high-transmission scenario. Without mAb PEP, the estimated cost of hospitalizations due to COVID-19 infections from household exposure in the lower transmission scenario was $149 million (95% UI, $115-$196 million), whereas the estimated hospitalization cost in the higher transmission scenario was $400 million (95% UI, $312-$508 million). In the lower transmission scenario, mAb PEP administered to 50% of eligible contacts aged 80 years and older was estimated to have 82% probability of saving costs, but was not associated with cost savings at age thresholds of 50 years and older or 20 years and older. In contrast, in the high-transmission scenario, mAb PEP administered to 50% of eligible household contacts had estimated cost savings in 100% of simulations at the 80-year age threshold, 96% of simulations at the 50-year threshold, and 2% of simulations at the 20-year thresholds.

CONCLUSIONS AND RELEVANCE

In this modeling study of a simulated US population, a mAb PEP for COVID-19 program was estimated to improve health outcomes and reduce costs. In the setting of a susceptible variant of SARS-CoV-2, health system and public health actors would have an opportunity to improve health and reduce net payer costs through COVID-19 PEP with mAbs.

Association of Subcutaneous or Intravenous Administration of Casirivimab and Imdevimab Monoclonal Antibodies With Clinical Outcomes in Adults With COVID-19

IMPORTANCE

Monoclonal antibody (mAb) treatment decreases hospitalization and death in high-risk outpatients with mild to moderate COVID-19; however, only intravenous administration has been evaluated in randomized clinical trials of treatment. Subcutaneous administration may expand outpatient treatment capacity and qualified staff available to administer treatment, but the association with patient outcomes is understudied.

OBJECTIVES

To evaluate whether subcutaneous casirivimab and imdevimab treatment is associated with reduced 28-day hospitalization and death compared with nontreatment among mAb-eligible patients and whether subcutaneous casirivimab and imdevimab treatment is clinically and statistically similar to intravenous casirivimab and imdevimab treatment.

DESIGN, SETTING, AND PARTICIPANTS

This prospective cohort study evaluated high-risk outpatients in a learning health system in the US with mild to moderate COVID-19 symptoms from July 14 to October 26, 2021, who were eligible for mAb treatment under emergency use authorization. A nontreated control group of eligible patients was also studied.

EXPOSURES

Subcutaneous injection or intravenous administration of the combined single dose of 600 mg of casirivimab and 600 mg of imdevimab.

MAIN OUTCOMES AND MEASURES

The primary outcome was the 28-day adjusted risk ratio or adjusted risk difference for hospitalization or death. Secondary outcomes included 28-day adjusted risk ratios and differences in hospitalization, death, a composite end point of emergency department admission and hospitalization, and rates of adverse events. Among 1959 matched adults with mild to moderate COVID-19, 969 patients (mean [SD] age, 53.8 [16.7] years; 547 women [56.4%]) who received casirivimab and imdevimab subcutaneously had a 28-day rate of hospitalization or death of 3.4% (22 of 653 patients) compared with 7.0% (92 of 1306 patients) in nontreated controls (risk ratio, 0.48; 95% CI, 0.30-0.80; P = .002). Among 2185 patients treated with subcutaneous (n = 969) or intravenous (n = 1216; mean [SD] age, 54.3 [16.6] years; 672 women [54.4%]) casirivimab and imdevimab, the 28-day rate of hospitalization or death was 2.8% vs 1.7%, which resulted in an adjusted risk difference of 1.5% (95% CI, -0.6% to 3.5%; P = .16). Among all infusion patients, there was no difference in intensive care unit admission (adjusted risk difference, 0.7%; 95% CI, -3.5% to 5.0%) or need for mechanical ventilation (adjusted risk difference, 0.2%; 95% CI, -5.8% to 5.5%).

CONCLUSIONS AND RELEVANCE

In this cohort study of high-risk outpatients with mild to moderate COVID-19 symptoms, subcutaneously administered casirivimab and imdevimab was associated with reduced hospitalization and death when compared with no treatment. These results provide preliminary evidence of potential expanded use of subcutaneous mAb treatment, particularly in areas that are facing treatment capacity and/or staffing shortages.

Initial Experience With SARS-CoV-2-Neutralizing Monoclonal Antibodies in Kidney or Combined Kidney-Pancreas Transplant Recipients

Background: Antiviral drugs have shown little impact in patient infected with acute respiratory coronavirus 2 (SARS-CoV-2). Especially for immunocompromised persons positive for SARS-CoV-2, novel treatments are warranted. Recently, the U.S. FDA has granted an emergency use authorization (EUA) to two monoclonal antibodies (mAb) targeting the viral spike protein: bamlanivimab and casivirimab and imdevimab. As per the EUA, all SARS-CoV-2 positive organ transplant recipients can receive mAb treatment. Patients and methods: We queried our center's transplant registry to identify SARS-CoV-2 infected recipients treated with single doses of either Bamlanivimab or casivirimab/imdevimab up to May 31, 2021. We analyzed clinical outcomes, renal function and virus-specific antibodies. The co-primary endpoints were hospitalization due to COVID-19 and SARS-CoV-2 RT-PCR negativity. Results: Thirteen patients at a median interval of 55 (IQR, 26-110) months from transplant were treated: 8 with bamlanivimab and 5 with casivirimab/imdevimab. In all, 4/13 (31%) patients were hospitalized at some time, while 11/13 (85%) achieved PCR negativity. 2/4 hospitalized patients received mAb as rescue treatment. Overall mortality was 23%, with one death attributable to transplant-associated lymphoma. All six patients infected with the B 1.1.7 variant were alive at last contact. Conclusion: mAb treatment appears effective when administered early to SARS-CoV-2-infected transplant recipients.

Progress and challenges for the machine learning-based design of fit-for-purpose monoclonal antibodies

Although the therapeutic efficacy and commercial success of monoclonal antibodies (mAbs) are tremendous, the design and discovery of new candidates remain a time and cost-intensive endeavor. In this regard, progress in the generation of data describing antigen binding and developability, computational methodology, and artificial intelligence may pave the way for a new era of in silico on-demand immunotherapeutics design and discovery. Here, we argue that the main necessary machine learning (ML) components for an in silico mAb sequence generator are: understanding of the rules of mAb-antigen binding, capacity to modularly combine mAb design parameters, and algorithms for unconstrained parameter-driven in silico mAb sequence synthesis. We review the current progress toward the realization of these necessary components and discuss the challenges that must be overcome to allow the on-demand ML-based discovery and design of fit-for-purpose mAb therapeutic candidates.

Capillary Isoelectric Focusing: Mass Spectrometry Method for the Separation and Online Characterization of Monoclonal Antibody Charge Variants at Intact and Subunit Levels

Monoclonal antibodies (mAbs) are one of the most widely used types of protein therapeutics. Charge variants are important quality attributes for evaluating developability, activity, and safety for mAb therapeutics. Here, we report a novel online capillary isoelectric focusing-mass spectrometry (CIEF-MS) method for mAb charge variant analysis using an electrokinetically pumped sheath-flow nanospray ion source on a time-of-flight (TOF) MS with a pressure-assisted chemical mobilization. Key factors that enable online CIEF-MS include effective capillary electrophoresis-MS (CE-MS) interface with enhanced sensitivity, utilization of MS-friendly electrolytes, beneficial effects of glycerol that reduces non-CIEF electrophoretic mobility and limits band broadening, appropriate ampholyte type and concentration selection for balanced separation resolution and MS detection sensitivity, optimized sheath liquid composition to realize high-resolution CIEF separation and effective MS electrospray ionization, as well as judiciously selected CIEF running parameters. The fundamental premise of CIEF has been verified by the linear correlation between isoelectric point (pI) values and migration time using a mixture of pI markers. By achieving high separation resolutions that are similar as those obtained from imaged CIEF (iCIEF), this method successfully provides highly sensitive MS identification for intact mAb charge variants. Furthermore, a middle-up sample treatment workflow can be adopted to provide in-depth charge variant analysis at subunit level for mAbs with complex charge heterogeneity. The mAb subunit CIEF-MS reveals the source of charge variant with enhanced resolution on both CIEF separation and MS spectra. This novel CIEF-MS method is a valuable tool with distinct advantage for objective and accurate assessment of charge heterogeneity of protein therapeutics.

Assessment of Macro- and Microheterogeneity of Monoclonal Antibodies Using Capillary Zone Electrophoresis Hyphenated with Mass Spectrometry

This chapter focuses on the application of capillary zone electrophoresis hyphenated with mass spectrometry (CZE-MS) for the characterization of monoclonal antibodies (mAbs). mAbs are complex molecules comprising different glycoforms and many other posttranslational modifications. In addition to this inherent microheterogeneity, misassembling of antibodies can take place during production contributing to their macroheterogeneity. CZE-MS is a versatile and powerful technique which has demonstrated high potential for the assessment of both micro- and macroheterogeneity of mAbs. In this chapter, technical and practical considerations for the characterization of mAbs by CZE-MS are described. CE-MS interfacing, capillary coatings for the prevention of mAb adsorption, and sample preparation considerations are covered in detail. The assessment of the macro- and microheterogeneity is discussed and exemplified through three different approaches involving analysis of intact, enzymatically digested, and reduced antibodies. The examples also illustrate the use of two commercially available interfacing techniques (i.e., sheath liquid and sheathless) as well as different types of capillary coatings (positively charged and neutral coatings).

OUP accepted manuscript

Background

Effective, long-acting prevention approaches are needed to reduce human immunodeficiency virus (HIV) incidence. We evaluated the safety and pharmacokinetics of VRC07-523LS and PGT121 administered subcutaneously alone and in combination as passive immunization for young women in South Africa.

Methods

CAPRISA 012A was a randomized, double-blinded, placebo-controlled, dose-escalation phase 1 trial. We enrolled 45 HIV-negative women into 9 groups and assessed safety, tolerability, pharmacokinetics, neutralization activity, and antidrug antibody levels. Pharmacokinetic modeling was conducted to predict steady-state concentrations for 12- and 24-weekly dosing intervals.

Results

VRC07-523LS and PGT121, administered subcutaneously, were safe and well tolerated. Most common reactogenicity events were injection site tenderness and headaches. Nine product-related adverse events were mild and transient. Median VRC07-523LS concentrations after 20 mg/kg doses were 9.65 μg/mL and 3.86 μg/mL at 16 and 24 weeks. The median week 8 concentration after the 10 mg/kg PGT121 dose was 8.26 μg/mL. Modeling of PGT121 at 20 mg/kg showed median concentrations of 1.37 μg/mL and 0.22 μg/mL at 16 and 24 weeks. Half-lives of VRC07-523LS and PGT121 were 29 and 20 days. Both antibodies retained neutralizing activity postadministration and no antidrug antibodies were detected.

Conclusions

Subcutaneous administration of VRC07-523LS in combination with optimized versions of PGT121 or other antibodies should be further assessed for HIV prevention.

Lamprey Variable Lymphocyte Receptor Monoclonal Antibodies for Whole-Cell Surface Antigens

Lamprey antibodies, the variable lymphocyte receptor B proteins (VLRB), have unique properties that make them promising alternatives to jawed vertebrate immunoglobulin domain antibodies. These leucine-rich repeat proteins exhibit a diversity on par with that of jawed vertebrate antibodies but are structurally completely distinct. VLRB antibodies have been successfully raised to a variety of antigens. A procedure for high-throughput screening of full-length lamprey VLRB libraries using whole cells is described here. Lamprey antibodies against cell surface antigens can be generated and screened quickly using this method.

Immunohistochemistry in Historical Perspective: Knowing the Past to Understand the Present

Immunohistochemistry is an extraordinary and extensively used technique whereby antibodies are used to detect antigens in cells within a tissue section. It has numerous applications in medicine, particularly in cancer diagnosis. It was Albert Hewett Coons, Hugh J Creech, Norman Jones, and Ernst Berliner who conceptualized and first implemented the procedure of immunofluorescence in 1941. They used fluorescein isothiocyanate (FITC)-labelled antibodies to localize pneumococcal antigens in infected tissues. Since then, with improvement and development of protein conjugation, enzyme labels have been introduced, such as peroxidase and alkaline phosphatase. The history of immunohistochemistry (IHC) combines physiology, immunology, biochemistry, and the work of various Nobel Prize laureates. From von Behring who was awarded de first Nobel Prize in 1901 for his work on serum therapy to the 1984 Nobel Prize for the discovery of monoclonal antibodies by Milstein, Kohler, and Jerne, IHC is a story of cooperation and collaboration which led to the development of this magnificent technique that is used daily in anatomical pathology laboratories worldwide.

Pancreatic cancer treatment with targeted therapies: are we there yet?

OBJECTIVE

Pancreatic cancer (PaCa) is a disease that is extremely difficult to treat and is associated with a high fatality rate. The majority of patients present to hospitals with metastatic or end-stage cancer, making the ultimate cure impossible. End-stage PaCa has no specific treatment, though surgery, irradiation, and chemotherapy can help patients live longer. Consequently, it is vital to accumulate all information on potential targeted therapies for this cancer into a single report.

MATERIALS AND METHODS

This review has been compiled using relevant keywords and a thorough web search utilising PubMed, ScienceDirect, GoogleScholar, Scopus, MEDLINE, and SpringerLink.

RESULTS

Conventional medicines that target various biological processes have a significant negative impact on normal cells. As a result, targeted therapies are required, which include the use of small-molecule inhibitors and monoclonal antibodies to target cancer cell surface receptors, growth factors, and other proteins involved in disease progression. In this review, we summarize the known targeted PaCa therapies, which include inhibitors of the KRAS, mTOR, and PI3K/AKT signaling pathways, as well as PARP, hedgehog, EGFR/ErbB, and TGF-β signaling pathways, along with inhibitors of the neurotrophic tropomyosin receptor kinase (NTRK).

CONCLUSIONS

An adequate understanding of PaCa pathogenesis and the adoption of tailored medicines can increase patients' overall survival. We believe targeted therapy can help patients with PaCa to have a better prognosis. As such, more research is needed to find appropriate biomarkers to aid in early tumor diagnosis and to discover novel prospective therapeutics based on the drugs listed in this article.