Vaccimel immunization is associated with enhanced response to treatment with anti-PD-1 monoclonal antibodies in cutaneous melanoma patients - a case reports study.

Cancer vaccines are gaining ground as immunotherapy options. We have previously demonstrated in cutaneous melanoma (CM) patients that adjuvant treatment with VACCIMEL, a mixture of four irradiated CM cell lines co-adjuvanted with BCG and GM-CSF, increases the cellular immune response to melanocyte differentiation antigens, cancer-testis antigens and neoantigens, with respect to basal levels. On the other hand, it is also known that treatment with anti-PD-1 monoclonal antibodies (MAbs), acting on pre-existing tumor-reactive lymphocytes, induces clinical responses in CM patients, albeit in a fraction of treated patients. A combination of both treatments would appear therefore desirable. In this paper, we describe CM patients who, having progressed even years after vaccination, were treated with anti-PD-1 MAbs. In 5/5 of such progressor patients, complete responses were obtained which lasted between 3 and 65+ months. Three of the patients remain disease-free and two recurred. One of the patients passed away after a recurrence of brain metastases. We suggest that clonally expanded reactive lymphocytes induced by VACCIMEL partially remain as memory cells, which may be recalled after tumor recurrence and may foster ulterior activity of anti-PD-1 MAbs.

Chondroitin sulfate proteoglycan 4: An attractive target for antibody-based immunotherapy.

Multifunctional molecules involved in tumor progression and metastasis have been identified as valuable targets for immunotherapy. Among these, chondroitin sulfate proteoglycan 4 (CSPG4), a significant tumor cell membrane-bound proteoglycan, has emerged as a promising target, especially in light of advances in chimeric antigen receptor (CAR) T-cell therapy. The profound bioactivity of CSPG4 and its role in pivotal processes such as tumor proliferation, migration, and neoangiogenesis underline its therapeutic potential. We reviewed the molecular intricacies of CSPG4, its functional attributes within tumor cells, and the latest clinical-translational advances targeting it. Strategies such as blocking monoclonal antibodies, conjugate therapies, bispecific antibodies, small-molecule inhibitors, CAR T-cell therapies, trispecific killer engagers, and ribonucleic acid vaccines against CSPG4 were assessed. CSPG4 overexpression in diverse tumors and its correlation with adverse prognostic outcomes emphasize its significance in cancer biology. These findings suggest that targeting CSPG4 offers a promising avenue for future cancer therapy, with potential synergistic effects when combined with existing treatments.

Safety and Efficacy of Golimumab in Indian Patients with Active Spondyloarthritis of Ankylosing Spondylitis or Psoriatic Arthritis: A Multicenter, Noncomparative, Open-Label, Real-World Study.

BACKGROUND: The safety and efficacy of tumor necrosis factor-α (TNF-α) inhibitor therapy for most common rheumatological diseases, ankylosing spondylitis (AS), and psoriatic arthritis (PsA) in controlled clinical trials is well-studied. This study evaluated subcutaneous (SC) golimumab in Indian patients with active spondyloarthritis (SpA) of AS or PsA in a real-world setting. MATERIALS AND METHODS: This phase 4, multicenter, prospective, non-comparative, interventional, 24-week study was performed in patients (age ≥18 years) with active SpA of AS or PsA (NCT03733925). Golimumab 50 mg was given subcutaneously to the patients every 4 weeks. Safety was assessed. The proportion of patients with AS and PsA achieving ≥20% improvement in the Assessment of SpA International Society 20 (ASAS20) criteria and American College of Rheumatology 20 (ACR20) responses, respectively, at weeks 14 and 24 were efficacy endpoints. RESULTS: Of the 100 patients enrolled (men: 78 [78.0%]; mean age: 36.7 [12.02] years), 94 (94.0%) patients completed the study. Treatment-emergent adverse events with golimumab were observed in 29/100 (29.0%) patients, and nasopharyngitis and upper respiratory tract infection (5.0% each) were the most common (≥5%). Deaths were not reported. At week 14, 74.5% (95% confidence interval [CI]: 59.7; 86.1%) of patients with AS and 84.6% (95% CI: 69.5; 94.1%) of patients with PsA achieved ASAS20 and ACR20 responses, which were sustained at week 24 (ASAS20: 66.0% [95% CI: 50.7, 79.1%]; ACR20: 93.2% [95% CI: 81.3, 98.6%]), respectively. CONCLUSION: Golimumab (50 mg) administered subcutaneously was safe and effective in Indian patients with active SpA of AS or PsA during the 24-week study period with no new safety signals.

[Preparation of a dual-specific antibody targeting human CD123 and exploration of its anti-acute myeloid leukemia effects].

Objective: To construct a novel dual-specific antibody targeting human CD123 (CD123 DuAb) and study its effects in acute myeloid leukemia (AML) . Methods: Based on the variable region of the CD123 monoclonal antibody independently developed at our institution, the CD123 DuAb expression plasmid was constructed by molecular cloning and transfected into ExpiCHO-S cells to prepare the antibody protein. Through a series of in vitro experiments, its activation and proliferation effect on T cells, as well as the effect of promoting T-cell killing of AML cells, were verified. Results: ① A novel CD123 DuAb plasmid targeting CD123 was successfully constructed and expressed in the Expi-CHO eukaryotic system. ②The CD123 DuAb could bind both CD3 on T cells and CD123 on CD123(+) tumor cells. ③When T cells were co-cultured with MV4-11 cells with addition of the CD123 DuAb at a concentration of 1 nmol/L, the positive expression rates of CD69 and CD25 on T cells were 68.0% and 44.3%, respectively, which were significantly higher than those of the control group (P<0.05). ④Co-culture with CD123 DuAb at 1 nmol/L promoted T-cell proliferation, and the absolute T-cell count increased from 5×10(5)/ml to 3.2×10(6)/ml on day 9, and CFSE fluorescence intensity decreased significantly. ⑤ With the increase in CD123 DuAb concentration in the culture system, T-cell exhaustion and apoptosis increased. When the CD123 DuAb was added at a concentration of 1 nmol/L to the culture system, the proportion of CD8(+) PD-1(+) LAG-3(+) T cells was 10.90%, and the proportion of propidium iodide (PI) (-) Annexin Ⅴ(+) T cells and PI(+) Annexin Ⅴ(+) T cells was 18.27% and 11.43%, respectively, which were significantly higher than those in the control group (P<0.05). ⑥ The CD123 DuAb significantly activated T cells, and the activation intensity was positively correlated with its concentration. The expression rate of CD107a on T cells reached 16.05% with 1 nmol/L CD123 DuAb, which was significantly higher than that of the control group (P<0.05). ⑦The CD123 DuAb promoted cytokine secretion by T cells at a concentration of 1 nmol/L, and the concentration of IFN-γ and TNF-α in the supernatant of the co-culture system reached 193.8 pg/ml and 169.8 pg/ml, respectively, which was significantly higher than that of the control group (P<0.05). ⑧When CD123 DuAb was added at a concentration of 1 nmol/L to the co-culture system of T cells and CD123(+) tumor cells, the killing intensity of T cells significantly increased, and the residual rates of CD123(+) MV4-11 cells, CD123(+) Molm13 cells, and CD123(+) THP-1 cells were 7.4%, 6.7%, and 14.6% on day 3, respectively, which were significantly lower than those in the control group (P<0.05) . Conclusion: In this study, a novel CD123 DuAb was constructed and expressed. In vitro experiments verified that the DuAb binds to CD123(+) tumor cells and T cells simultaneously, promotes T-cell activation and proliferation, and facilitates their anti-leukemia effect, which provides a basis for further clinical research.

GNUV201, a novel human/mouse cross-reactive and low pH-selective anti-PD-1 monoclonal antibody for cancer immunotherapy.

BACKGROUND: Several PD-1 antibodies approved as anti-cancer therapies work by blocking the interaction of PD-1 with its ligand PD-L1, thus restoring anti-cancer T cell activities. These PD-1 antibodies lack inter-species cross-reactivity, necessitating surrogate antibodies for preclinical studies, which may limit the predictability and translatability of the studies. RESULTS: To overcome this limitation, we have developed an inter-species cross-reactive PD-1 antibody, GNUV201, by utilizing an enhanced diversity mouse platform (SHINE MOUSE™). GNUV201 equally binds to human PD-1 and mouse PD-1, equally inhibits the binding of human PD-1/PD-L1 and mouse PD-1/PD-L1, and effectively suppresses tumor growth in syngeneic mouse models. The epitope of GNUV201 mapped to the "FG loop" of hPD-1, distinct from those of Keytruda® ("C'D loop") and Opdivo® (N-term). Notably, the structural feature where the protruding epitope loop fits into GNUV201's binding pocket supports the enhanced binding affinity due to slower dissociation (8.7 times slower than Keytruda®). Furthermore, GNUV201 shows a stronger binding affinity at pH 6.0 (5.6 times strong than at pH 7.4), which mimics the hypoxic and acidic tumor microenvironment (TME). This phenomenon is not observed with marketed antibodies (Keytruda®, Opdivo®), implying that GNUV201 achieves more selective binding to and better occupancy on PD-1 in the TME. CONCLUSIONS: In summary, GNUV201 exhibited enhanced affinity for PD-1 with slow dissociation and preferential binding in TME-mimicking low pH. Human/monkey/mouse inter-species cross-reactivity of GNUV201 could enable more predictable and translatable efficacy and toxicity preclinical studies. These results suggest that GNUV201 could be an ideal antibody candidate for anti-cancer drug development.

Tinostamustine (EDO-S101), an Alkylating Deacetylase Inhibitor, Enhances the Efficacy of Daratumumab in Multiple Myeloma by Upregulation of CD38 and NKG2D Ligands.

Multiple myeloma is a malignancy characterized by the accumulation of malignant plasma cells in bone marrow and the production of monoclonal immunoglobulin. A hallmark of cancer is the evasion of immune surveillance. Histone deacetylase inhibitors have been shown to promote the expression of silenced molecules and hold potential to increase the anti-MM efficacy of immunotherapy. The aim of the present work was to assess the potential effect of tinostamustine (EDO-S101), a first-in-class alkylating deacetylase inhibitor, in combination with daratumumab, an anti-CD38 monoclonal antibody (mAb), through different preclinical studies. Tinostamustine increases CD38 expression in myeloma cell lines, an effect that occurs in parallel with an increment in CD38 histone H3 acetylation levels. Also, the expression of MICA and MICB, ligands for the NK cell activating receptor NKG2D, augments after tinostamustine treatment in myeloma cell lines and primary myeloma cells. Pretreatment of myeloma cell lines with tinostamustine increased the sensitivity of these cells to daratumumab through its different cytotoxic mechanisms, and the combination of these two drugs showed a higher anti-myeloma effect than individual treatments in ex vivo cultures of myeloma patients' samples. In vivo data confirmed that tinostamustine pretreatment followed by daratumumab administration significantly delayed tumor growth and improved the survival of mice compared to individual treatments. In summary, our results suggest that tinostamustine could be a potential candidate to improve the efficacy of anti-CD38 mAbs.

Preclinical characterization of a novel investigational monoclonal antibody CM313 with potent CD38-positive cell killing activity.

Introduction: CM313 is currently under clinical investigation for treatments of multiple myeloma, systemic lupus erythematosus, and immune thrombocytopenia. We aimed to report the preclinical profile of the novel therapeutic anti-CD38 monoclonal antibody (mAb) CM313, with an emphasis on the difference with other CD38-targeting mAb. Methods: The binding of CM313 to CD38 recombinant protein across species was assessed using ELISA. The binding of CM313 to CD38-positive (CD38+) cells was detected using flow cytometry assays. CM313-induced complement-dependent cytotoxicity (CDC), antibody-dependent cellular cytotoxicity (ADCC), antibody-dependent cellular phagocytosis (ADCP) and apoptosis on different CD38+ cells were assessed by LDH release assays or flow cytometry assays. The effect of CM313 on CD38 enzymatic activity was measured using fluorescence spectroscopy. CM313 immunotoxicity in human blood was assessed using flow cytometry assays, ELISA, and LDH release assays. Anti-tumor activity of CM313 was assessed in multiple mouse xenograft models. Safety profile of CM313 were evaluated in cynomolgus monkeys and human CD38 transgenic (B-hCD38) mice. Results: There exist unique sequences at complementarity-determining regions (CDR) of CM313, which facilitates its affinity to CD38 is consistently higher across a spectrum of CD38+ cell lines than daratumumab. In vitro studies showed that CM313 induces comparable killing activity than daratumumab, including ADCC, CDC, ADCP, apoptosis induced by Fc-mediated cross-linking, and effectively inhibited the enzymatic activity of CD38. However, CM313 showed more potent CDC than isatuximab. In vivo, CM313 dose-dependently inhibited xenograft tumor growth, both as a monotherapy and in combination with dexamethasone or lenalidomide. Furthermore, CM313 was well tolerated with no drug-related clinical signs or off-target risks, as evidenced by 4-week repeat-dose toxicology studies in cynomolgus monkeys and B-hCD38 mice, with the later study showing no observed adverse effect level (NOAEL) of 300mg/kg once weekly. Discussion: CM313 is a novel investigational humanized mAb with a distinct CDR sequence, showing comparable killing effects with daratumumab and stronger CDC activity than isatuximab, which supports its clinical development.

Stabilized trimeric peptide immunogens of the complete HIV-1 gp41 N-heptad repeat and their use as HIV-1 vaccine candidates.

Efforts to develop an HIV-1 vaccine include those focusing on conserved structural elements as the target of broadly neutralizing monoclonal antibodies. MAb D5 binds to a highly conserved hydrophobic pocket on the gp41 N-heptad repeat (NHR) coiled coil and neutralizes through prevention of viral fusion and entry. Assessment of 17-mer and 36-mer NHR peptides presenting the D5 epitope in rodent immunogenicity studies showed that the longer peptide elicited higher titers of neutralizing antibodies, suggesting that neutralizing epitopes outside of the D5 pocket may exist. Although the magnitude and breadth of neutralization elicited by NHR-targeting antigens are lower than that observed for antibodies directed to other epitopes on the envelope glycoprotein complex, it has been shown that NHR-directed antibodies are potentiated in TZM-bl cells containing the FcγRI receptor. Herein, we report the design and evaluation of covalently stabilized trimeric 51-mer peptides encompassing the complete gp41 NHR. We demonstrate that these peptide trimers function as effective antiviral entry inhibitors and retain the ability to present the D5 epitope. We further demonstrate in rodent and nonhuman primate immunization studies that our 51-mer constructs elicit a broader repertoire of neutralizing antibody and improved cross-clade neutralization of primary HIV-1 isolates relative to 17-mer and 36-mer NHR peptides in A3R5 and FcγR1-enhanced TZM-bl assays. These results demonstrate that sensitive neutralization assays can be used for structural enhancement of moderately potent neutralizing epitopes. Finally, we present expanded trimeric peptide designs which include unique low-molecular-weight scaffolds that provide versatility in our immunogen presentation strategy.

Durvalumab Plus Gemcitabine and Cisplatin Versus Gemcitabine and Cisplatin in Biliary Tract Cancer: a Real-World Retrospective, Multicenter Study.

BACKGROUND: The TOPAZ-1 phase III trial reported a survival benefit with the anti-programmed cell death ligand 1 (anti-PD-L1) durvalumab in combination with gemcitabine and cisplatin in patients with advanced biliary tract cancer (BTC). OBJECTIVE: The present study investigated for the first time the impact on survival of adding durvalumab to cisplatin/gemcitabine compared with cisplatin/gemcitabine in a real-world setting. PATIENTS AND METHODS: The analyzed population included patients with unresectable, locally advanced, or metastatic BTC treated with durvalumab in combination with cisplatin/gemcitabine or with cisplatin/gemcitabine alone. The impact of adding durvalumab to chemotherapy in terms of overall survival (OS) and progression free survival (PFS) was investigated with univariate and multivariate analysis. RESULTS: Overall, 563 patients were included in the analysis: 213 received cisplatin/gemcitabine alone, 350 received cisplatin/gemcitabine plus durvalumab. At the univariate analysis, the addition of durvalumab was found to have an impact on survival, with a median OS of 14.8 months versus 11.2 months [hazard ratio (HR) 0.63, 95% confidence interval (CI) 0.50-0.80, p = 0.0002] in patients who received cisplatin/gemcitabine plus durvalumab compared to those who received cisplatin/gemcitabine alone. At the univariate analysis for PFS, the addition of durvalumab to cisplatin/gemcitabine demonstrated a survival impact, with a median PFS of 8.3 months and 6.0 months (HR 0.57, 95% CI 0.47-0.70, p < 0.0001) in patients who received cisplatin/gemcitabine plus durvalumab and cisplatin/gemcitabine alone, respectively. The multivariate analysis confirmed that adding durvalumab to cisplatin/gemcitabine is an independent prognostic factor for OS and PFS, with patients > 70 years old and those affected by locally advanced disease experiencing the highest survival benefit. Finally, an exploratory analysis of prognostic factors was performed in the cohort of patients who received durvalumab: neutrophil-lymphocyte ratio (NLR) and disease stage were to be independent prognostic factors in terms of OS. The interaction test highlighted NLR ≤ 3, Eastern Cooperative Oncology Group Performance Status (ECOG PS) = 0, and locally advanced disease as positive predictive factors for OS on cisplatin/gemcitabine plus durvalumab. CONCLUSION: In line with the results of the TOPAZ-1 trial, adding durvalumab to cisplatin/gemcitabine has been confirmed to confer a survival benefit in terms of OS and PFS in a real-world setting of patients with advanced BTC.

From standard therapies to monoclonal antibodies and immune checkpoint inhibitors - an update for reconstructive surgeons on common oncological cases.

Malignancies represent a persisting worldwide health burden. Tumor treatment is commonly based on surgical and/or non-surgical therapies. In the recent decade, novel non-surgical treatment strategies involving monoclonal antibodies (mAB) and immune checkpoint inhibitors (ICI) have been successfully incorporated into standard treatment algorithms. Such emerging therapy concepts have demonstrated improved complete remission rates and prolonged progression-free survival compared to conventional chemotherapies. However, the in-toto surgical tumor resection followed by reconstructive surgery oftentimes remains the only curative therapy. Breast cancer (BC), skin cancer (SC), head and neck cancer (HNC), and sarcoma amongst other cancer entities commonly require reconstructive surgery to restore form, aesthetics, and functionality. Understanding the basic principles, strengths, and limitations of mAB and ICI as (neo-) adjuvant therapies and treatment alternatives for resectable or unresectable tumors is paramount for optimized surgical therapy planning. Yet, there is a scarcity of studies that condense the current body of literature on mAB and ICI for BC, SC, HNC, and sarcoma. This knowledge gap may result in suboptimal treatment planning, ultimately impairing patient outcomes. Herein, we aim to summarize the current translational endeavors focusing on mAB and ICI. This line of research may serve as an evidence-based fundament to guide targeted therapy and optimize interdisciplinary anti-cancer strategies.

Antibody Isolation in C. neoformans.

The importance of humoral immunity to fungal infections remains to be elucidated. In cryptococcosis, patients that fail to generate antibodies against antigens of the fungus Cryptococcus neoformans are more susceptible to the disease, demonstrating the importance of these molecules to the antifungal immune response. Historically, antibodies against C. neoformans have been applied in diagnosis, therapeutics, and as important research tools to elucidate fungal biology. Throughout the process of generating monoclonal antibodies (mAbs) from a single B-cell clone and targeting a single epitope, several immunization steps might be required for the detection of responsive antibodies to the antigen of interest in the serum. This complex mixture of antibodies comprises the polyclonal antibodies. To obtain mAbs, B-lymphocytes are harvested (from spleen or peripheral blood) and fused with tumor myeloma cells, to generate hybridomas that are individually cloned and specifically screened for mAb production. In this chapter, we describe all the necessary steps, from the immunization to polyclonal antibody harvesting, hybridoma generation, and mAb production and purification. Additionally, we discuss new cutting-edge approaches for generating interspecies mAbs, such as humanized mAbs, or for similar species in distinct host backgrounds.

The role of the size of affinity ligands in the detection and characterization of extracellular vesicles.

Surface proteins on the membrane of nano-sized extracellular vesicles (EVs) not only play crucial roles in cell-to-cell communication, but also are specific binding targets for EV detection, isolation and tracking. The low abundance of protein biomarkers on EV surface, the formation of clusters and the complex EV surface network impose significant challenges to the study of EVs. Employing bulky sized affinity ligands, such as antibodies, in the detection and characterization of these vesicles often result in reduced sensitivity of detection or poor quantification of proteins on the EV surface. By virtue of their small size and high specificity, Affibody molecules emerge as a potential alternative to their monoclonal antibody counterparts as robust affinity ligands in EV research. In this study, we present a theoretical framework on the superiority of anti-HER2 Affibodies over anti-HER2 antibodies in labeling and detecting HER2-positive EVs, followed by the demonstration of the advantages of HER2 Affibodies in accessing EV surface and the detection of EVs through multiple types of approaches including fluorescence intensity, colorimetry, and fluorescence polarization. HER2 Affibodies outperformed by 10-fold over three HER2 antibody clones in accessing HER2-positive EVs derived from different human cancer cell lines. Furthermore, HRP-Affibody molecules could detect EVs from cancer cells spiked into human serum with at least a 2-fold higher sensitivity compared with that of their antibody counterparts. In addition, in fluorescence polarization assays in which no separation of free from bound ligand is required, FITC-labeled HER2 Affibodies could sensitively detect HER2-positive EVs with a clinically relevant limit of detection, whilst HER2 antibodies failed to detect EVs in the same conditions. With the demonstrated superiority in accessing and detecting surface targets over bulky-sized antibodies in EVs, Affibodies may become the next-generation of affinity ligands in the precise characterization and quantification of molecular architecture on the surface of EVs.

Durvalumab plus gemcitabine and cisplatin in advanced biliary tract cancer (TOPAZ-1): patient-reported outcomes from a randomised, double-blind, placebo-controlled, phase 3 trial.

BACKGROUND: In the ongoing, randomised, double-blind phase 3 TOPAZ-1 study, durvalumab, a PD-L1 inhibitor, plus gemcitabine and cisplatin was associated with significant improvements in overall survival compared with placebo, gemcitabine, and cisplatin in people with advanced biliary tract cancer at the pre-planned intermin analysis. In this paper, we present patient-reported outcomes from TOPAZ-1. METHODS: In TOPAZ-1 (NCT03875235), participants aged 18 years or older with previously untreated, unresectable, locally advanced, or metastatic biliary tract cancer with an Eastern Cooperative Oncology Group performance status of 0 or 1 and one or more measurable lesions per Response Evaluation Criteria in Solid Tumors (RECIST; version 1.1) were randomly assigned (1:1) to the durvalumab group or the placebo group using a computer-generated randomisation scheme. Participants received 1500 mg durvalumab or matched placebo intravenously every 3 weeks (on day 1 of the cycle) for up to eight cycles in combination with 1000 mg/m2 gemcitabine and 25 mg/m2 cisplatin intravenously on days 1 and 8 every 3 weeks for up to eight cycles. Thereafter, participants received either durvalumab (1500 mg) or placebo monotherapy intravenously every 4 weeks until disease progression or other discontinuation criteria were met. Randomisation was stratified by disease status (initially unresectable vs recurrent) and primary tumour location (intrahepatic cholangiocarcinoma vs extrahepatic cholangiocarcinoma vs gallbladder cancer). Patient-reported outcomes were assessed as a secondary outcome in all participants who completed the European Organisation for Research and Treatment of Cancer's 30-item Quality of Life of Cancer Patients questionnaire (QLQ-C30) and the 21-item Cholangiocarcinoma and Gallbladder Cancer Quality of Life Module (QLQ-BIL21). We calculated time to deterioration-ie, time from randomisation to an absolute decrease of at least 10 points in a patient-reported outcome that was confirmed at a subsequent visit or the date of death (by any cause) in the absence of deterioration-and adjusted mean change from baseline in patient-reported outcomes. FINDINGS: Between April 16, 2019, and Dec 11, 2020, 685 participants were enrolled and randomly assigned, 341 to the durvalumab group and 344 to the placebo group. Overall, 345 (50%) of participants were male and 340 (50%) were female. Data for the QLQ-C30 were available for 318 participants in the durvalumab group and 328 in the placebo group (median follow-up 9·9 months [IQR 6·7 to 14·1]). Data for the QLQ-BIL21 were available for 305 participants in the durvalumab group and 322 in the placebo group (median follow-up 10·2 months [IQR 6·7 to 14·3]). The proportions of participants in both groups who completed questionnaires were high and baseline scores were mostly similar across treatment groups. For global health status or quality of life, functioning, and symptoms, we noted no difference in time to deterioration or adjusted mean changes from baseline were observed between groups. Median time to deterioration of global health status or quality of life was 7·4 months (95% CI 5·6 to 8·9) in the durvalumab group and 6·7 months (5·6 to 7·9) in the placebo group (hazard ratio 0·87 [95% CI 0·69 to 1·12]). The adjusted mean change from baseline was 1·23 (95% CI -0·71 to 3·16) in the durvalumab group and 0·35 (-1·63 to 2·32) in the placebo group. INTERPRETATION: The addition of durvalumab to gemcitabine and cisplatin did not have a detrimental effect on patient-reported outcomes. These results suggest that durvalumab, gemcitabine, and cisplatin is a tolerable treatment regimen in patients with advanced biliary tract cancer. FUNDING: AstraZeneca.

Treatment Patterns and Attrition With Lines of Therapy for Advanced Urothelial Carcinoma in the US.

Importance: The treatment paradigm for advanced urothelial carcinoma (aUC) has undergone substantial transformation due to the introduction of effective, novel therapeutic agents. However, outcomes remain poor, and little is known about current treatment approaches and attrition rates for patients with aUC. Objectives: To delineate evolving treatment patterns and attrition rates in patients with aUC using a US-based patient-level sample. Design, Setting, and Participants: This retrospective cohort study used patient-level data from the nationwide deidentified electronic health record database Flatiron Health, originating from approximately 280 oncology clinics across the US. Patients included in the analysis received treatment for metastatic or local aUC at a participating site from January 1, 2011, to January 31, 2023. Patients receiving treatment for 2 or more different types of cancer or participating in clinical trials were excluded from the analysis. Main Outcomes and Measures: Frequencies and percentages were used to summarize the (1) treatment received in each line (cisplatin-based regimens, carboplatin-based regimens, programmed cell death 1 and/or programmed cell death ligand 1 [PD-1/PD-L1] inhibitors, single-agent nonplatinum chemotherapy, enfortumab vedotin, erdafitinib, sacituzumab govitecan, or others) and (2) attrition of patients with each line of therapy, defined as the percentage of patients not progressing to the next line. Results: Of the 12 157 patients within the dataset, 7260 met the eligibility criteria and were included in the analysis (5364 [73.9%] men; median age at the start of first-line treatment, 73 [IQR, 66-80] years). All patients commenced first-line treatment; of these, only 2714 (37.4%) progressed to receive second-line treatment, and 857 (11.8%) advanced to third-line treatment. The primary regimens used as first-line treatment contained carboplatin (2241 [30.9%]), followed by PD-1/PD-L1 inhibitors (2174 [29.9%]). The PD-1/PD-L1 inhibitors emerged as the predominant choice in the second- and third-line (1412 of 2714 [52.0%] and 258 of 857 [30.1%], respectively) treatments. From 2019 onward, novel therapeutic agents were increasingly used in second- and third-line treatments, including enfortumab vedotin (219 of 2714 [8.1%] and 159 of 857 [18.6%], respectively), erdafitinib (39 of 2714 [1.4%] and 28 of 857 [3.3%], respectively), and sacituzumab govitecan (14 of 2714 [0.5%] and 34 of 857 [4.0%], respectively). Conclusions and Relevance: The findings of this cohort study suggest that approximately two-thirds of patients with aUC did not receive second-line treatment. Most first-line treatments do not include cisplatin-based regimens and instead incorporate carboplatin- or PD-1/PD-L1 inhibitor-based therapies. These data warrant the provision of more effective and tolerable first-line treatments for patients with aUC.

Clinical outcomes of pomalidomide-based and daratumumab-based therapies in patients with relapsed/refractory multiple myeloma: A real-world cohort study in China.

BACKGROUND: Comparative investigations evaluating the efficacy of pomalidomide-based (Pom-based) versus daratumumab-based (Dara-based) therapies in patients with relapsed/refractory multiple myeloma (RRMM) remain scarce, both in randomized controlled trials and real-world studies. METHODS: This retrospective cohort study included 140 RRMM patients treated with Pom-based or Dara-based or a combination of pomalidomide and daratumumab (DPd) regimens in a Chinese tertiary hospital between December 2018 and July 2023. RESULTS: The overall response rates (ORR) for Pom-based (n = 48), Dara-based (n = 68), and DPd (n = 24) groups were 57.8%, 84.6%, and 75.0%, respectively (p = 0.007). At data cutoff on August 1, 2023, the median progression-free survival (PFS) was 5.7 months (95% CI: 5.0-6.5) for the Pom-based group, 10.5 months (5.2-15.8) for the Dara-based group, and 6.7 months (4.0-9.3) for the DPd group (p = 0.056). Multivariate analysis identified treatment regimens (Dara-based vs. Pom-based, DPd vs. Pom-based) and Eastern Cooperative Oncology Group performance status (ECOG PS) as independent prognostic factors for PFS. In the subgroups of patients aged >65 years, with ECOG PS ≥2, lines of therapy ≥2, extramedullary disease or double-refractory disease (refractory to both lenalidomide and proteasome inhibitors), the superiority of Dara-based regimens over Pom-based regimens was not evident. A higher incidence of infections was observed in patients receiving Dara-based and DPd regimens (Pom-based 39.6% vs. Dara-based 64.7% vs. DPd 70.8%, p = 0.009). CONCLUSIONS: In real-world settings, Pom-based, Dara-based, and DPd therapies exhibited favorable efficacy in patients with RRMM. Dara-based therapy yielded superior clinical response and PFS compared to Pom-based therapy.

Application of quantitative protein mass spectrometric data in the early predictive analysis of membrane-bound target engagement by monoclonal antibodies.

Model-informed drug discovery advocates the use of mathematical modeling and simulation for improved efficacy in drug discovery. In the case of monoclonal antibodies (mAbs) against cell membrane antigens, this requires quantitative insight into the target tissue concentration levels. Protein mass spectrometry data are often available but the values are expressed in relative, rather than in molar concentration units that are easier to incorporate into pharmacokinetic models. Here, we present an empirical correlation that converts the parts per million (ppm) concentrations in the PaxDb database to their molar equivalents that are more suitable for pharmacokinetic modeling. We evaluate the insight afforded to target tissue distribution by analyzing the likely tumor-targeting accuracy of mAbs recognizing either epidermal growth factor receptor or its homolog HER2. Surprisingly, the predicted tissue concentrations of both these targets exceed the Kd values of their respective therapeutic mAbs. Physiologically based pharmacokinetic (PBPK) modeling indicates that in these conditions only about 0.05% of the dosed mAb is likely to reach the solid tumor target cells. The rest of the dose is eliminated in healthy tissues via both nonspecific and target-mediated processes. The presented approach allows evaluation of the interplay between the target expression level in different tissues that determines the overall pharmacokinetic properties of the drug and the fraction that reaches the cells of interest. This methodology can help to evaluate the efficacy and safety properties of novel drugs, especially if the off-target cell degradation has cytotoxic outcomes, as in the case of antibody-drug conjugates.

CARs derived from broadly neutralizing, human monoclonal antibodies identified by single B cell sorting target hepatitis B virus-positive cells.

To design new CARs targeting hepatitis B virus (HBV), we isolated human monoclonal antibodies recognizing the HBV envelope proteins from single B cells of a patient with a resolved infection. HBV-specific memory B cells were isolated by incubating peripheral blood mononuclear cells with biotinylated hepatitis B surface antigen (HBsAg), followed by single-cell flow cytometry-based sorting of live, CD19+ IgG+ HBsAg+ cells. Amplification and sequencing of immunoglobulin genes from single memory B cells identified variable heavy and light chain sequences. Corresponding immunoglobulin chains were cloned into IgG1 expression vectors and expressed in mammalian cells. Two antibodies named 4D06 and 4D08 were found to be highly specific for HBsAg, recognized a conformational and a linear epitope, respectively, and showed broad reactivity and neutralization capacity against all major HBV genotypes. 4D06 and 4D08 variable chain fragments were cloned into a 2nd generation CAR format with CD28 and CD3zeta intracellular signaling domains. The new CAR constructs displayed a high functional avidity when expressed on primary human T cells. CAR-grafted T cells proved to be polyfunctional regarding cytokine secretion and killed HBV-positive target cells. Interestingly, background activation of the 4D08-CAR recognizing a linear instead of a conformational epitope was consistently low. In a preclinical model of chronic HBV infection, murine T cells grafted with the 4D06 and the 4D08 CAR showed on target activity indicated by a transient increase in serum transaminases, and a lower number of HBV-positive hepatocytes in the mice treated. This study demonstrates an efficient and fast approach to identifying pathogen-specific monoclonal human antibodies from small donor cell numbers for the subsequent generation of new CARs.

[The 505th case: refractory ascites and monoclonal immunoglobulin].

A 52-year-old woman was admitted with a primary complaint of abdominal distension and increased abdominal circumference for more than half a year. There was no evidence of infection or solid tumor on abdominocentesis or laparoscopic surgery. Concurrently, smoldering multiple myeloma was diagnosed. Due to refractory ascites and portal hypertension, a transjugular intrahepatic portosystemic shunt was performed, but the efficacy was not satisfactory. As the anemia progressed, she was finally diagnosed with active multiple myeloma after monoclonal plasma cells were detected in the ascites by flow cytometry. Treated with a triplet regimen that included bortezomib, cyclophosphamide, and dexamethasone (BCD), she achieved a very good partial response and ascites regressed.

Translational PET Imaging of Nectin-4 Expression in Multiple Different Cancers with 68Ga-N188.

Nectin cell adhesion molecule 4 (nectin-4) is a transmembrane protein overexpressed on a variety of cancers and plays an important role in oncogenic and metastatic processes. The nectin-4-targeted antibody-drug conjugate enfortumab vedotin has been approved for treating locally advanced or metastatic urothelial cancer, but the efficacy in other types of cancer remains to be explored. The aim of this study was to evaluate the feasibility of nectin-4-targeted PET imaging with 68Ga-N188 as a noninvasive method to quantify membranous nectin-4 expression in multiple tumor types-an approach that may provide insight for patient stratification and treatment selection. Methods: Sixty-two patients with 16 types of cancer underwent head-to-head 68Ga-N188 and 18F-FDG PET/CT imaging for initial staging or detection of recurrence and metastases. Correlation between lesion SUVmax and nectin-4 expression determined by immunohistochemistry staining was analyzed in 36 of 62 patients. Results: The SUVmax of 68Ga-N188 had a positive correlation with membranous nectin-4 expression in the various tumor types tested (r = 0.458; P = 0.005), whereas no association was observed between the SUVmax and cytoplasmic nectin-4 expression. The detection rates for patient-based analysis of 68Ga-N188 and 18F-FDG PET/CT examinations were comparable (95.00% [57/60] vs. 93.33% [56/60]). In patients with pancreatic cancer, 68Ga-N188 exhibited a potential advantage for detecting residual or locally recurrent tumors; this advantage may assist in clinical decision-making. Conclusion: The correlation between nectin-4-targeted 68Ga-N188 PET imaging and membranous nectin-4 expression indicates the potential of 68Ga-N188 as an effective tool for selecting patients who may benefit from enfortumab vedotin treatment. The PET imaging results provided evidence to explore nectin-4-targeted therapy in a variety of tumors. 68Ga-N188 may improve the restaging of pancreatic cancer but requires further evaluation in a powered, prospective setting.