[Successful polatuzumab vedotin and rituximab therapy for post-CAR-T relapse of diffuse large B-cell lymphoma].

Relapse or progressive disease after chimeric antigen receptor T-cell (CAR-T) treatment remains a major issue for poor-risk aggressive large B-cell lymphoma. However, limited data are available on post-CAR-T use of polatuzumab vedotin. Here we describe the case of a patient with diffuse large B-cell lymphoma (DLBCL) who experienced relapse three months after CD19-directed CAR-T therapy with tisagenlecleucel. However, the relapsed lesions rapidly disappeared following treatment with polatuzumab vedotin and rituximab. Notably, long-term remission was achieved without severe cytopenia, infections or peripheral neuropathy, showing the therapeutic benefit of polatuzumab vedotin for CAR-T failure.

[Chinese expert consensus on maintenance treatment with anti-EGFR monoclonal antibody for RAS wild-type metastatic colorectal cancer (2024 edition)].

For patients with metastatic colorectal cancer (mCRC) who achieve disease control during first-line standard therapy, post-induction strategies should emphasize on quality of life improvement while maintaining disease control. Chemotherapy combined with anti-epidermal growth factor receptor (EGFR) monoclonal antibody is the standard first-line treatment for RAS wild-type mCRC patients. After anti-EGFR-based first-line induction therapy achieves at least stable disease, anti-EGFR-based maintenance treatment could maintain disease control while keeping a good safety profile. Based on research evidence and clinical practice, the Chinese expert consensus on anti-EGFR-based maintenance strategy for RAS wild-type mCRC aims to futher clarify the treatment timing, regimen options, adverse reaction management and follow-up strategy, providing standardized guidance to maximize the clinical benefit in RAS wild-type mCRC.

Treatment for Covid-19 with SARS-CoV-2 neutralizing antibody BRII-196(Ambavirumab) plus BRII-198(Lomisivir): a retrospective cohort study.

BACKGROUND: Monoclonal antibody therapy for Covid-19 springs up all over the world and get some efficiency. This research aims to explore the treating effect of BRII-196(Ambavirumab) plus BRII-198(Lomisivir) on Covid-19. METHODS: In this retrospective cohort research, patients received standard care or plus BRII-196 /BRII-198 monoclonal antibodies. General comparison of clinical indexes and prognosis between Antibody Group and Control Group was made. Further, according to the antibody using time and patients' condition, subgroups included Early antibody group, Late antibody group, Mild Antibody Group, Mild Control Group, Severe Antibody Group and Severe Control Group. RESULTS: Length of stay(LOS) and interval of Covid-19 nucleic acid from positive to negative of Antibody Group were 12.0(IQR 9.0-15.0) and 14.0(IQR 10.0-16.0) days, less than those(13.0 (IQR 11.0-18.0) and 15.0 (IQR 12.8-17.0) days) of Control Group(p = 0.004, p = 0.004). LOS(median 10days) of Early Antibody Group was the shortest, significantly shorter than that of Control Group (median 13days)(p < 0.001). Interval(median 12days) of Covid-19 nucleic acid from positive to negative of Early Antibody Group also was significantly shorter than that of Control Group(median 15days) and Late Antibody Group(median 14days)(p = 0.001, p = 0.042). LOS(median 12days) and interval(median 13days) of Covid-19 nucleic acid from positive to negative of Mild Antibody Group was shorter than that of Mild Control Group(median 13days; median 14.5days)(p = 0.018, p = 0.033). CONCLUSION: The neutralizing antibody therapy, BRII-196 plus BRII-198 could shorten LOS and interval of Covid-19 nucleic acid from positive to negative. However, it didn't show efficacy for improving clinical outcomes among severe or critical cases.

Validation of two immunoassays for oxytocin measurements in human saliva.

The objective of this research was to develop and validate two immunoassays for oxytocin measurement in human saliva, one using a monoclonal and the other a polyclonal antibody against oxytocin, whose affinity for oxytocin was tested by an antibody mapping epitope analysis. These assays were analytically validated and used to compare oxytocin concentrations with those obtained with a commercial kit before and after the extraction or reduction/alkylation (R/A) treatments to saliva samples. The assays were also used to evaluate changes in salivary oxytocin concentrations following a physical effort and an induced psychological stress, which have previously been described as situations that cause an increase in salivary oxytocin. Both assays showed to be precise and accurate in the validation studies, and the antibodies used showed a defined binding region in case of the monoclonal antibody, whereas the polyclonal antibody showed binding events through all the oxytocin sequence. Although the monoclonal and polyclonal assays showed a positive correlation, they give results in a different range of magnitude. Both assays showed significant increases in oxytocin concentrations when applied after the physical effort and the psychological stress. This study shows that a variability in the reported values of oxytocin can occur depending on the assay and indicates that the use of different types of antibodies can give a different range of values when measuring oxytocin in saliva.

Size exclusion chromatography of biopharmaceutical products: From current practices for proteins to emerging trends for viral vectors, nucleic acids and lipid nanoparticles.

The 21st century has been particularly productive for the biopharmaceutical industry, with the introduction of several classes of innovative therapeutics, such as monoclonal antibodies and related compounds, gene therapy products, and RNA-based modalities. All these new molecules are susceptible to aggregation and fragmentation, which necessitates a size variant analysis for their comprehensive characterization. Size exclusion chromatography (SEC) is one of the reference techniques that can be applied. The analytical techniques for mAbs are now well established and some of them are now emerging for the newer modalities. In this context, the objective of this review article is: i) to provide a short historical background on SEC, ii) to suggest some clear guidelines on the selection of packing material and mobile phase for successful method development in modern SEC; and iii) to highlight recent advances in SEC, such as the use of narrow-bore and micro-bore columns, ultra-wide pore columns, and low-adsorption column hardware. Some important innovations, such as recycling SEC, the coupling of SEC with mass spectrometry, and the use of alternative detectors such as charge detection mass spectrometry and mass photometry are also described. In addition, this review discusses the use of SEC in multidimensional setups and shows some of the most recent advances at the preparative scale. In the third part of the article, the possibility of SEC for the characterization of new modalities is also reviewed. The final objective of this review is to provide a clear summary of opportunities and limitations of SEC for the analysis of different biopharmaceutical products.

Updated cost-effectiveness analysis of adebrelimab plus chemotherapy for extensive-stage small cell lung cancer in China.

OBJECTIVE: The CAPSTONE-1 trial demonstrated that adebrelimab-based immunotherapy yielded a favourable survival benefit compared with chemotherapy for patients with extensive-stage small cell lung cancer (ES-SCLC). This study aims to evaluate the cost-effectiveness of this immunotherapy in the treatment of ES-SCLC from a healthcare system perspective in China. DESIGN: The TreeAge Pro software was used to establish a three-state partitioned survival model. Survival data came from the CAPSTONE-1 trial (NCT03711305), and only direct medical costs were included. Utility values were obtained from the published literature. Sensitivity analysis was performed to explore the robustness of the model. The cost-effectiveness of immunotherapy was investigated through scenario and exploratory analyses in various settings. OUTCOME MEASURES: Total costs, incremental costs, life years, quality-adjusted life-years (QALYs), incremental QALYs and incremental cost-effectiveness ratio (ICER). RESULTS: The basic analysis revealed that the adebrelimab group achieved a total of 1.1 QALYs at a cost of US$65 385, while the placebo group attained 0.78 QALYs at a cost of US$12 741. ICER was US$163 893/QALY. Sensitivity analysis confirmed that the model was robust. Results from scenario and exploratory analyses indicated that the combination of adebrelimab and chemotherapy did not demonstrate cost-effectiveness in any scenario. CONCLUSIONS: From the perspective of the Chinese healthcare system, adebrelimab in combination with chemotherapy for the treatment of ES-SCLC was not economical compared with chemotherapy.

Daratumumab treatment in six highly sensitised solid organ transplant recipients: A case series and literature review.

We report data on six kidney or heart recipients who were administered daratumumab to treat or prevent antibody-mediated rejection (ABMR). To date, data are scarce concerning the use of daratumumab in solid organ transplantation and most reports show a decrease in donor-specific antigen (DSA) levels and an improvement in ABMR using a multiple myeloma daratumumab administration scheme, that is, with sequential systematic administration. Here, we report on the efficacy of daratumumab 1/ in reducing the histological signs of ABMR, 2/ in reducing the ability of DSA to bind to donor cells in vitro through negativation of flow cytometry crossmatching, 3/ in preferentially being directed towards antibodies sharing epitopes, suggesting that daratumumab may specifically target activated plasma cells, 4/ and when administered as a single dose. This last point suggests, for the first time, that, as for rituximab in auto-immune diseases, the scheme for daratumumab administration could be different for targeting DSA-producing plasma cells than for tumour cells.

Computer-aided design space identification for screening of protein A affinity chromatography resins.

The rapidly growing market of monoclonal antibodies (mAbs) within the biopharmaceutical industry has incentivised numerous works on the design of more efficient production processes. Protein A affinity chromatography is regarded as one of the best processes for the capture of mAbs. Although the screening of Protein A resins has been previously examined, process flexibility has not been considered to date. Examining performance alongside flexibility is crucial for the design of processes that can handle disturbances arising from the feed stream. In this work, we present a model-based approach for the identification of design spaces, enhanced by machine learning. We demonstrate its capabilities on the design of a Protein A chromatography unit, screening five industrially relevant resins. The computational results favourably compare to experimental data and a resin performance comparison is presented. An improvement on the computational time by a factor of 300,000 is achieved using the machine learning aided methodology. This allowed for the identification of 5,120 different design spaces in only 19 h.

Design and characterization of protective pan-ebolavirus and pan-filovirus bispecific antibodies.

Monoclonal antibodies (mAbs) are an important class of antiviral therapeutics. MAbs are highly selective, well tolerated, and have long in vivo half-life as well as the capacity to induce immune-mediated virus clearance. Their activities can be further enhanced by integration of their variable fragments (Fvs) into bispecific antibodies (bsAbs), affording simultaneous targeting of multiple epitopes to improve potency and breadth and/or to mitigate against viral escape by a single mutation. Here, we explore a bsAb strategy for generation of pan-ebolavirus and pan-filovirus immunotherapeutics. Filoviruses, including Ebola virus (EBOV), Sudan virus (SUDV), and Marburg virus (MARV), cause severe hemorrhagic fever. Although there are two FDA-approved mAb therapies for EBOV infection, these do not extend to other filoviruses. Here, we combine Fvs from broad ebolavirus mAbs to generate novel pan-ebolavirus bsAbs that are potently neutralizing, confer protection in mice, and are resistant to viral escape. Moreover, we combine Fvs from pan-ebolavirus mAbs with those of protective MARV mAbs to generate pan-filovirus protective bsAbs. These results provide guidelines for broad antiviral bsAb design and generate new immunotherapeutic candidates.

Structural Characterization of a Pathogenic Antibody Underlying Vaccine-Induced Immune Thrombotic Thrombocytopenia (VITT).

Vaccine-induced immune thrombotic thrombocytopenia (VITT) is a rare but dangerous side effect of adenoviral-vectored COVID-19 vaccines. VITT had been linked to production of autoantibodies recognizing platelet factor 4 (PF4). Here, we characterize anti-PF4 antibodies obtained from a VITT patient's blood. Intact mass measurements indicate that a significant fraction of these antibodies represent a limited number of clones. MS analysis of large antibody fragments (the light chain and the Fc/2 and Fd fragments of the heavy chain) confirms the monoclonal nature of this component of the anti-PF4 antibodies repertoire and reveals the presence of a mature complex biantennary N-glycan within the Fd segment. Peptide mapping using two complementary proteases and LC-MS/MS was used to determine the amino acid sequence of the entire light chain and over 98% of the heavy chain (excluding a short N-terminal segment). The sequence analysis allows the monoclonal antibody to be assigned to the IgG2 subclass and verifies that the light chain belongs to the λ-type. Incorporation of enzymatic de-N-glycosylation into the peptide mapping routine allows the N-glycan in the Fab region of the antibody to be localized to the framework 3 region of the VH domain. This novel N-glycosylation site is the result of a single mutation within the germline sequence. Peptide mapping also provides information on lower-abundance (polyclonal) components of the anti-PF4 antibody ensemble, revealing the presence of all four subclasses (IgG1-IgG4) and both types of the light chain (λ and κ). This case study demonstrates the power of combining the intact, middle-down, and bottom-up MS approaches for meaningful characterization of ultralow quantities of pathogenic antibodies extracted directly from patients' blood.

Quantification of lipoprotein lipase in mouse plasma with a sandwich enzyme-linked immunosorbent assay.

To support in vivo and in vitro studies of intravascular triglyceride metabolism in mice, we created rat monoclonal antibodies (mAbs) against mouse LPL. Two mAbs, mAbs 23A1 and 31A5, were used to develop a sandwich ELISA for mouse LPL. The detection of mouse LPL by the ELISA was linear in concentrations ranging from 0.31 ng/ml to 20 ng/ml. The sensitivity of the ELISA made it possible to quantify LPL in serum and in both pre-heparin and post-heparin plasma samples (including in grossly lipemic samples). LPL mass and activity levels in the post-heparin plasma were lower in Gpihbp1-/- mice than in wild-type mice. In both groups of mice, LPL mass and activity levels were positively correlated. Our mAb-based sandwich ELISA for mouse LPL will be useful for any investigator who uses mouse models to study LPL-mediated intravascular lipolysis.

Clinical Pharmacology of the Antibody-Drug Conjugate Enfortumab Vedotin in Advanced Urothelial Carcinoma and Other Malignant Solid Tumors.

Enfortumab vedotin is an antibody-drug conjugate comprised of a human monoclonal antibody directed to Nectin-4 and monomethyl auristatin E (MMAE), a microtubule-disrupting agent. The objectives of this review are to summarize the clinical pharmacology of enfortumab vedotin monotherapy and demonstrate that the appropriate dose has been selected for clinical use. Pharmacokinetics (PK) of enfortumab vedotin (antibody-drug conjugate and total antibody) and free MMAE were evaluated in five clinical trials of patients with locally advanced or metastatic urothelial carcinoma (n = 748). Intravenous enfortumab vedotin 0.5-1.25 mg/kg on days 1, 8, and 15 of a 28-day cycle showed linear, dose-proportional PK. No significant differences in exposure or safety of enfortumab vedotin and free MMAE were observed in mild, moderate, or severe renal impairment versus normal renal function. Patients with mildly impaired versus normal hepatic function had a 37% increase in area under the concentration-time curve (0-28 days), a 31% increase in maximum concentration of free MMAE, and a similar adverse event profile. No clinically significant PK differences were observed based on race/ethnicity with weight-based dosing, and no clinically meaningful QT prolongation was observed. Concomitant use with dual P-glycoprotein and strong cytochrome P450 3A4 inhibitors may increase MMAE exposure and the risk of adverse events. Approximately 3% of patients developed antitherapeutic antibodies against enfortumab vedotin 1.25 mg/kg. These findings support enfortumab vedotin 1.25 mg/kg monotherapy on days 1, 8, and 15 of a 28-day cycle. No dose adjustments are required for patients with renal impairment or mild hepatic impairment, or by race/ethnicity.

Purification of monoclonal antibodies using novel 3D printed ordered stationary phases.

3D printing offers the unprecedented ability to fabricate chromatography stationary phases with bespoke 3D morphology as opposed to traditional packed beds of spherical beads. The restricted range of printable materials compatible with chromatography is considered a setback for its industrial implementation. Recently, we proposed a novel ink that exhibits favourable printing performance (printing time ∼100 mL/h, resolution ∼200 µm) and broadens the possibilities for a range of chromatography applications thanks to its customisable surface chemistry. In this work, this ink was used to fabricate 3D printed ordered columns with 300 µm channels for the capture and polishing of therapeutic monoclonal antibodies. The columns were initially assessed for leachables and extractables, revealing no material propensity for leaching. Columns were then functionalised with protein A and SO3 ligands to obtain affinity and strong cation exchangers, respectively. 3D printed protein A columns showed >85 % IgG recovery from harvested cell culture fluid with purities above 98 %. Column reusability was evaluated over 20 cycles showing unaffected performance. Eluate samples were analysed for co-eluted protein A fragments, host cell protein and aggregates. Results demonstrate excellent HCP clearance (logarithmic reduction value of > 2.5) and protein A leakage in the range of commercial affinity resins (<100 ng/mg). SO3 functionalised columns employed for polishing achieved removal of leaked Protein A (down to 10 ng/mg) to meet regulatory expectations of product purity. This work is the first implementation of 3D printed columns for mAb purification and provides strong evidence for their potential in industrial bioseparations.

Generation and characterization of monoclonal antibodies against pathologically phosphorylated TDP-43.

Inclusions containing TAR DNA binding protein 43 (TDP-43) are a pathological hallmark of frontotemporal dementia (FTD) and amyotrophic lateral sclerosis (ALS). One of the disease-specific features of TDP-43 inclusions is the aberrant phosphorylation of TDP-43 at serines 409/410 (pS409/410). Here, we developed rabbit monoclonal antibodies (mAbs) that specifically detect pS409/410-TDP-43 in multiple model systems and FTD/ALS patient samples. Specifically, we identified three mAbs (26H10, 2E9 and 23A1) from spleen B cell clones that exhibit high specificity and sensitivity to pS409/410-TDP-43 peptides in an ELISA assay. Biochemical analyses revealed that pS409/410 of recombinant TDP-43 and of exogenous 25 kDa TDP-43 C-terminal fragments in cultured HEK293T cells are detected by all three mAbs. Moreover, the mAbs detect pS409/410-positive TDP-43 inclusions in the brains of FTD/ALS patients and mouse models of TDP-43 proteinopathy by immunohistochemistry. Our findings indicate that these mAbs are a valuable resource for investigating TDP-43 pathology both in vitro and in vivo.

Induction of NK cell reactivity against acute myeloid leukemia by Fc-optimized CD276 (B7-H3) antibody.

Acute myeloid leukemia (AML) remains a therapeutic challenge despite recent therapeutic advances. Although monoclonal antibodies (mAbs) engaging natural killer (NK) cells via antibody-dependent cellular cytotoxicity (ADCC) hold promise in cancer therapy, almost none have received clinical approval for AML, so far. Recently, CD276 (B7-H3) has emerged as a promising target for AML immunotherapy, due to its high expression on leukemic blasts of AML patients. Here, we present the preclinical development of the Fc-optimized CD276 mAb 8H8_SDIE with enhanced CD16 affinity. We demonstrate that 8H8_SDIE specifically binds to CD276 on AML cell lines and primary AML cells and induces pronounced NK cell activation and degranulation as measured by CD69, CD25, and CD107a. Secretion of IFNγ, TNF, granzyme B, granulysin, and perforin, which mediate NK cell effector functions, was induced by 8H8_SDIE. A pronounced target cell-restricted lysis of AML cell lines and primary AML cells was observed in cytotoxicity assays using 8H8_SDIE. Finally, xenograft models with 8H8_SDIE did not cause off-target immune activation and effectively inhibited leukemia growth in vivo. We here present a novel attractive immunotherapeutic compound that potently induces anti-leukemic NK cell reactivity in vitro and in vivo as treatment option for AML.

Cost-effectiveness analysis of durvalumab, tremelimumab, and etoposide-platinum in first-line treatment of extensive-stage small cell lung cancer.

BACKGROUND: Durvalumab plus etoposide-platinum (DEP) showed sustained overall survival improvements in patients with extensive-stage small-cell lung cancer (ES-SCLC) compared to etoposide-platinum (EP), but adding tremelimumab to DEP (DTEP) did not significantly improve outcomes. A third-party payer perspective is taken here to evaluate the cost-effectiveness of DTEP, DEP, and EP for ES-SCLC. METHODS: The cost-effectiveness was evaluated by partitioning survival models into 3 mutually exclusive health states. In this model, clinical characteristics and outcomes were obtained from the CASPIAN. Model robustness was evaluated through 1-way deterministic and probabilistic sensitivity analyses. Outcome measurements included costs, quality-adjusted life-years (QALYs), incremental cost-effectiveness ratio, life-years, incremental net health benefit, and incremental net monetary benefit. The analysis was conducted with a 10-year lifetime horizon in a United States setting. RESULTS: Compared with EP, DEP, and DTEP were associated with an increment of 0.480 and 0.313 life-years, and an increment of 0.247 and 0.165 QALYs, as well as a $139,788 and $170,331 increase in cost per patient. The corresponding ICERs were $565,807/QALY and $1033,456/QALY, respectively. The incremental net health benefit and incremental net monetary benefit of DEP or DTEP were -0.685 QALYs and -$102,729, or -0.971 QALYs and -$145,608 at a willingness to pay threshold of $150,000/QALY, respectively. Compared with DTEP, DEP was dominated. DTEP and DEP were 100% unlikely to be cost-effective if the willingness to pay threshold was $150,000/QALY. DEP was cost-effective compared to EP when durvalumab was priced below $0.994/mg. Compared with EP, DEP, and DTEP were unlikely to be considered cost-effective across all subgroups. CONCLUSION: DEP and DTEP were not cost-effective options in the first-line treatment for ES-SCLC compared with EP, from the third-party payer perspective in the United States. Compared with DTEP, DEP was dominated.

A nanowell platform to identify, sort and expand high antibody-producing cells.

Increased use of therapeutic monoclonal antibodies and the relatively high manufacturing costs fuel the need for more efficient production methods. Here we introduce a novel, fast, robust, and safe isolation platform for screening and isolating antibody-producing cell lines using a nanowell chip and an innovative single-cell isolation method. An anti-Her2 antibody producing CHO cell pool was used as a model. The platform; (1) Assures the single-cell origin of the production clone, (2) Detects the antibody production of individual cells and (3) Isolates and expands the individual cells based on their antibody production. Using the nanowell platform we demonstrated an 1.8-4.5 increase in anti-Her2 production by CHO cells that were screened and isolated with the nanowell platform compared to CHO cells that were not screened. This increase was also shown in Fed-Batch cultures where selected high production clones showed titers of 19-100 mg/L on harvest day, while the low producer cells did not show any detectable anti-Her2 IgG production. The screening of thousands of single cells is performed under sterile conditions and the individual cells were cultured in buffers and reagents without animal components. The time required from seeding a single cell and measuring the antibody production to fully expanded clones with increased Her-2 production was 4-6 weeks.

Targeting PD-1/PD-L-1 immune checkpoint inhibition for cancer immunotherapy: success and challenges.

The programmed death-1 receptor (PD-1) acts as a T-cell brake, and its interaction with ligand-1 (PD-L-1) interferes with signal transduction of the T-cell receptor. This leads to suppression of T-cell survival, proliferation, and activity in the tumor microenvironment resulting in compromised anticancer immunity. PD-1/PD-L-1 interaction blockade shown remarkable clinical success in various cancer immunotherapies. To date, most PD-1/PD-L-1 blockers approved for clinical use are monoclonal antibodies (mAbs); however, their therapeutic use are limited owing to poor clinical responses in a proportion of patients. mAbs also displayed low tumor penetration, steep production costs, and incidences of immune-related side effects. This strongly indicates the importance of developing novel inhibitors as cancer immunotherapeutic agents. Recently, advancements in the small molecule-based inhibitors (SMIs) that directly block the PD-1/PD-L-1 axis gained attention from the scientific community involved in cancer research. SMIs demonstrated certain advantages over mAbs, including longer half-lives, low cost, greater cell penetration, and possibility of oral administration. Currently, several SMIs are in development pipeline as potential therapeutics for cancer immunotherapy. To develop new SMIs, a wide range of structural scaffolds have been explored with excellent outcomes; biphenyl-based scaffolds are most studied. In this review, we analyzed the development of mAbs and SMIs targeting PD-1/PD-L-1 axis for cancer treatment. Altogether, the present review delves into the problems related to mAbs use and a detailed discussion on the development and current status of SMIs. This article may provide a comprehensive guide to medicinal chemists regarding the potential structural scaffolds required for PD-1/PD-L-1 interaction inhibition.