Tisotumab vedotin in patients with advanced or metastatic solid tumours (InnovaTV 201): a first-in-human, multicentre, phase 1-2 trial

Arising Novel Agents in Lung Cancer: Are Bispecifics and ADCs the New Paradigm?

Lung cancer is one of the most common cancers with the highest mortality. Non-small cell lung cancer (NSCLC) contributes to around 85% of lung cancer diagnoses (vs. 15% for small cell lung cancer). The treatment of NSCLC has vastly changed in the last two decades since the development of immunotherapy and targeted therapy against driver mutations. As is the nature of malignancy, cancer cells have acquired resistance to these treatments prompting an investigation into novel treatments and new targets. Bispecific antibodies, capable of targeting multiple substrates at once, and antibody-drug conjugates that can preferentially deliver chemotherapy to tumor cells are examples of this innovation. From our initial evaluation, both treatment modalities appear promising.

Tissue factor (coagulation factor III): a potential double-edge molecule to be targeted and re-targeted toward cancer

Tissue factor (TF) is a protein that plays a critical role in blood clotting, but recent research has also shown its involvement in cancer development and progression. Herein, we provide an overview of the structure of TF and its involvement in signaling pathways that promote cancer cell proliferation and survival, such as the PI3K/AKT and MAPK pathways. TF overexpression is associated with increased tumor aggressiveness and poor prognosis in various cancers. The review also explores TF's role in promoting cancer cell metastasis, angiogenesis, and venous thromboembolism (VTE). Of note, various TF-targeted therapies, including monoclonal antibodies, small molecule inhibitors, and immunotherapies have been developed, and preclinical and clinical studies demonstrating the efficacy of these therapies in various cancer types are now being evaluated. The potential for re-targeting TF toward cancer cells using TF-conjugated nanoparticles, which have shown promising results in preclinical studies is another intriguing approach in the path of cancer treatment. Although there are still many challenges, TF could possibly be a potential molecule to be used for further cancer therapy as some TF-targeted therapies like Seagen and Genmab's tisotumab vedotin have gained FDA approval for treatment of cervical cancer. Overall, based on the overviewed studies, this review article provides an in-depth overview of the crucial role that TF plays in cancer development and progression, and emphasizes the potential of TF-targeted and re-targeted therapies as potential approaches for the treatment of cancer.

Preclinical Efficacy of the Antibody-Drug Conjugate CLDN6-23-ADC for the Treatment of CLDN6-Positive Solid Tumors

PURPOSE

Claudin-6 (CLDN6) is expressed at elevated levels in multiple human cancers including ovarian and endometrial malignancies, with little or no detectable expression in normal adult tissue. This expression profile makes CLDN6 an ideal target for development of a potential therapeutic antibody-drug conjugate (ADC). This study describes the generation and preclinical characterization of CLDN6-23-ADC, an ADC consisting of a humanized anti-CLDN6 monoclonal antibody coupled to monomethyl auristatin E (MMAE) via a cleavable linker.

EXPERIMENTAL DESIGN

A fully humanized anti-CLDN6 antibody was conjugated to MMAE resulting in the potential therapeutic ADC, CLDN6-23-ADC. The antitumor efficacy of CLDN6-23-ADC was assessed for antitumor efficacy in CLDN6-positive (CLDN6+) and -negative (CLDN6-) xenografts and patient-derived xenograft (PDX) models of human cancers.

RESULTS

CLDN6-23-ADC selectively binds to CLDN6, versus other CLDN family members, inhibits the proliferation of CLDN6+ cancer cells in vitro, and is rapidly internalized in CLDN6+ cells. Robust tumor regressions were observed in multiple CLDN6+ xenograft models and tumor inhibition led to markedly enhanced survival of CLDN6+ PDX tumors following treatment with CLDN6-23-ADC. IHC assessment of cancer tissue microarrays demonstrate elevated levels of CLDN6 in 29% of ovarian epithelial carcinomas. Approximately 45% of high-grade serous ovarian carcinomas and 11% of endometrial carcinomas are positive for the target.

CONCLUSIONS

We report the development of a novel ADC, CLDN6-23-ADC, that selectively targets CLDN6, a potential onco-fetal-antigen which is highly expressed in ovarian and endometrial cancers. CLDN6-23-ADC exhibits robust tumor regressions in mouse models of human ovarian and endometrial cancers and is currently undergoing phase I study.

Antibody-Drug Conjugates in the Treatment of Urothelial Cancer

Antibody-drug conjugates (ADCs) have transformed the treatment landscape in oncology and become an essential therapeutic modality. In urothelial carcinoma (UC), the two ADCs that have been especially successful in clinical practice are enfortumab vedotin and sacituzumab govitecan. These drugs are currently approved as monotherapy for later lines of treatment in locally advanced or metastatic UC and have had a significant impact for patients with limited treatment options. Combinational trials, as well as additional ADCs, are currently being investigated in the treatment of UC for subsequent lines of therapy as overall survival rates remain dismal.

Antibody-Drug Conjugates in Lung Cancer: Recent Advances and Implementing Strategies

Antibody-drug conjugates (ADCs) are one of the fastest-growing oncology therapeutics, merging the cytotoxic effect of conjugated payload with the high specific ability and selectivity of monoclonal antibody targeted on a specific cancer cell membrane antigen. The main targets for ADC development are antigens commonly expressed by lung cancer cells, but not in normal tissues. They include human epidermal growth factor receptor 2, human epidermal growth factor receptor 3, trophoblast cell surface antigen 2, c-MET, carcinoembryonic antigen-related cell adhesion molecule 5, and B7-H3, each with one or more specific ADCs that showed encouraging results in the lung cancer field, more in non-small-cell lung cancer than in small-cell lung cancer histology. To date, multiple ADCs are under evaluation, alone or in combination with different molecules (eg, chemotherapy agents or immune checkpoint inhibitors), and the optimal strategy for selecting patients who may benefit from the treatment is evolving, including an improvement of biomarker understanding, involving markers of resistance or response to the payload, besides the antibody target. In this review, we discuss the available evidence and future perspectives on ADCs for lung cancer treatment, including a comprehensive discussion on structure-based drug design, mechanism of action, and resistance concepts. Data were summarized by specific target antigen, biology, efficacy, and safety, differing among ADCs according to the ADC payload and their pharmacokinetics and pharmacodynamics properties.

CD142 Identifies Neoplastic Desmoid Tumor Cells, Uncovering Interactions Between Neoplastic and Stromal Cells That Drive Proliferation

The interaction between neoplastic and stromal cells within a tumor mass plays an important role in cancer biology. However, it is challenging to distinguish between tumor and stromal cells in mesenchymal tumors because lineage-specific cell surface markers typically used in other cancers do not distinguish between the different cell subpopulations. Desmoid tumors consist of mesenchymal fibroblast-like cells driven by mutations stabilizing beta-catenin. Here we aimed to identify surface markers that can distinguish mutant cells from stromal cells to study tumor-stroma interactions. We analyzed colonies derived from single cells from human desmoid tumors using a high-throughput surface antigen screen, to characterize the mutant and nonmutant cells. We found that CD142 is highly expressed by the mutant cell populations and correlates with beta-catenin activity. CD142-based cell sorting isolated the mutant population from heterogeneous samples, including one where no mutation was previously detected by traditional Sanger sequencing. We then studied the secretome of mutant and nonmutant fibroblastic cells. PTX3 is one stroma-derived secreted factor that increases mutant cell proliferation via STAT6 activation. These data demonstrate a sensitive method to quantify and distinguish neoplastic from stromal cells in mesenchymal tumors. It identifies proteins secreted by nonmutant cells that regulate mutant cell proliferation that could be therapeutically.

Significance

Distinguishing between neoplastic (tumor) and non-neoplastic (stromal) cells within mesenchymal tumors is particularly challenging, because lineage-specific cell surface markers typically used in other cancers do not differentiate between the different cell subpopulations. Here, we developed a strategy combining clonal expansion with surface proteome profiling to identify markers for quantifying and isolating mutant and nonmutant cell subpopulations in desmoid tumors, and to study their interactions via soluble factors.

Investigational drugs for recurrent or primary advanced metastatic cervical cancer: what is in the clinical development pipeline?

INTRODUCTION

Recurrent or primary advanced metastatic cervical cancer (R/M CC) has a poor prognosis with a 5-year-survival rate of 16.5%, demanding novel and improved therapies for the treatment of these patients. The first-line standard of care for R/M CC now benefits from the addition of the immune checkpoint inhibitor, pembrolizumab, to platinum-based chemotherapy with paclitaxel and bevacizumab. Additionally, new options for second-line treatment have become available in recent years.

AREAS COVERED

Here, we review current investigational drugs and discuss their relative targets, efficacies, and potential within the R/M CC treatment landscape. This review will focus on recently published data and key ongoing clinical trials in patients with R/M CC, covering multiple modes of action, including immunotherapies, antibody-drug conjugates, and tyrosine kinase inhibitors. We searched clinicaltrials.gov for ongoing trials and pubmed.ncbi.nih.gov for recently published trial data, as well as recent years' proceedings from the annual conferences of the American Society of Clinical Oncology (ASCO), European Society for Medical Oncology (ESMO), European Society of Gynaecological Oncology (ESGO), and the International Gynecologic Cancer Society (IGCS).

EXPERT OPINION

Therapeutics currently attracting attention include novel immune checkpoint inhibitors, therapeutic vaccinations, antibody-drug conjugates, such as tisotumab vedotin, tyrosine kinase inhibitors targeting HER2, and multitarget synergistic combinations.

A review of the novel tissue factor antibody-drug conjugate: Tisotumab vedotin

OBJECTIVE

To review and compare the pharmacology, efficacy, and safety of the novel tissue factor antibody-drug conjugate, tisotumab vedotin.

DATA SOURCES

Literature search was performed through PubMed MEDLINE, Google Scholar, ClinicalTrials.gov, and the Food and Drug Administration.

DATA SUMMARY

Tisotumab vedotin, a novel tissue factor antibody-drug conjugate, was granted accelerated approval by the US FDA on 20 September 2021 for adult patients with recurrent or metastatic cervical cancer with disease progression on or after chemotherapy. Tisotumab vedotin demonstrated clinical efficacy in a number of solid tumors in innovaTV 201 and more specifically in cervical cancer in the pivotal phase 2 innovaTV 204. In the single-arm innovaTV 204 study, 101 patients with recurrent or metastatic cervical cancer received intravenous tisotumab vedotin at the recommended dose of 2 mg/kg every 3 weeks until disease progression or unacceptable toxicity. The independent review committee confirmed an objective response rate of 24% with 7% complete responses and 17% partial responses. Tisotumab vedotin is associated with several notable adverse events with data from innovaTV 204 including ocular toxicity, hemorrhage, and peripheral neuropathy. Ninety-two percent of patients experienced treatment-related adverse events with 28% experiencing an adverse event of grade 3 or higher.

CONCLUSIONS

Metastatic cervical cancer has a high risk of relapse with few effective second-line therapeutic options. Current guidelines recommend single agent tisotumab vedotin as a possible option. Ongoing trials will further define its place in therapy.

Tisotumab vedotin in recurrent or metastatic cervical cancer

Tisotumab vedotin (TV) is an antibody-drug conjugate used for the treatment of adult patients with recurrent or metastatic cervical cancer. TV comprised of a monoclonal antibody against tissue factor and monomethyl auristatin E (MMAE), a potent inhibitor of cell division. The innovaTV-201 and innovaTV-204/GO30xx/ENGOT-cx6 trials showed that TV has clinically meaningful and durable antitumor activity in pretreated patients with recurrent or metastatic cervical cancer. The innovaTV-204 trial showed that TV monotherapy resulted in an objective response rate of 24% (including 7% and 17% complete and partial responses, respectively). In September 2021, the US Food and Drugs Administration (FDA) granted accelerated approval to TV for the treatment of recurrent or metastatic cervical cancer patients with disease progression on or after chemotherapy. The ongoing randomized, open-label Phase 3 innovaTV-301/ENGOTcx12/GOG-30xx trial will assess the effect of TV in pre-treated recurrent or metastatic cervical cancer. Meanwhile, the phase 1b/2 trial ENGOT Cx8/GOG 3024/innovaTV-205 is testing other possible combination between TV and other treatments. TV is characterized by a promising antitumor activity and an acceptable safety profile. Moreover, the preliminary data highlighted the feasibility of using TV in first line. In the first line, TV in combination with carboplatin or pembrolizumab provides an ORR of 55% and 41%, respectively Although the effect of adding TV to the current standard of care in first-line (carboplatin plus pembrolizumab) is still under evaluation, we expected to observe impressive results in the cervical cancer population.

Antibody-Drug Conjugates in Prostate Cancer: A Systematic Review

The prognosis in the setting of metastatic castration-resistant prostate cancer patients (mCRPC) remains limited. Therefore, novel treatment strategies remain an unmet need. Antibody-drug conjugates (ADC) emerged as a new drug concept with the potential to deliver a cytotoxic payload with limited off-target toxicity and potentially bystander effect. Following the success of ADCs in breast cancer and urothelial tumours, their activity in prostate cancer is now under investigation. Thus, the aim of this systematic review was to identify published and ongoing prospective clinical trials regarding ADC treatment in prostate cancer. A systematic search of PubMed, MEDLINE, and Web of Science was conducted as per PRISMA guidelines to identify prospective clinical trials of ADCin prostate cancer. Trials are currently ongoing on ClinicalTrials.gov and in the EU. The Clinical Trials Register was also identified. Abstracts, publications in languages other than English, review articles, retrospective analyses, and phase I trials were excluded. A total of six phase I/II prospective clinical trials already published were included. Seven ongoing trials were also identified. All studies were in the refractory/advanced tumour setting, and two included only mCRPC patients. The ADC targets were prostate-specific membrane antigen (PSMA), trophoblast cell surface antigen-2 (TROP-2), six-transmembrane epithelial antigen of prostate-1 (STEAP-1), tissue factor (TF), delta-like protein 3 (DLL-3), B7-H3 family of proteins (B7-H3), and human epidermal growth factor receptor 2 (HER2). Regarding the efficacy of PSMA ADC treatment in the second-line or beyond mCRPC setting, a PSA ≥ 50% decline rate in 14% of all treated patients was reported. One patient achieved a complete response with TROP-2 ADC. Overall, a wide range of safety issues were raised, particularly in connection with neuropathy and hematologic toxicity. Novel therapies have been changing the scope of treatment in mCRPC. ADCs seem to provide efficacy benefits, even with potential toxicity. The results of most prospective ongoing studies are still awaited, and a longer follow-up time is warranted to evaluate the real impact of ADCs in PCa.

Perspectives on the future of urothelial carcinoma therapy: chemotherapy and beyond

INTRODUCTION

Despite recent developments in the landscape of urothelial carcinoma (UC) treatment, platinum combination chemotherapy still remains a milestone. Recently immunotherapeutic agents have gained ever-growing attractivity, particularly in the metastatic setting. Novel chemotherapeutic strategies and agents, such as antibody-drug conjugates (ADCs), and powerful combination regimens have been developed to overcome the resistance of most UC to current therapies.

AREAS COVERED

Herein, we review the current standard-of-care chemotherapy, the development of ADCs, the rationale for combining therapy regimens with chemotherapy in current trials, and future directions in UC management.

EXPERT OPINION

Immunotherapy has prompted a revolution in the treatment paradigm of UC. However, only a few patients experience a long-term response when treated with single-agent immunotherapies. Combination treatments are necessary to bypass resistance mechanisms and broaden the clinical utility of current options. Current evidence supports the intensification of standard-of-care chemotherapy with maintenance immunotherapy. However, the optimal sequence, combination, and duration must be determined to achieve individual longevity with acceptable health-related quality of life. In that regard, ADCs appear as a promising alternative for single and combination strategies in UC, as they specifically target the tumor cells, thereby, theoretically improving treatment efficacy and avoiding extensive off-target toxicities.

Mechanisms of ADC Toxicity and Strategies to Increase ADC Tolerability

Anti-cancer antibody-drug conjugates (ADCs) aim to expand the therapeutic index of traditional chemotherapy by employing the targeting specificity of monoclonal antibodies (mAbs) to increase the efficiency of the delivery of potent cytotoxic agents to malignant cells. In the past three years, the number of ADCs approved by the Food and Drug Administration (FDA) has tripled. Although several ADCs have demonstrated sufficient efficacy and safety to warrant FDA approval, the clinical use of all ADCs leads to substantial toxicity in treated patients, and many ADCs have failed during clinical development due to their unacceptable toxicity profiles. Analysis of the clinical data has demonstrated that dose-limiting toxicities (DLTs) are often shared by different ADCs that deliver the same cytotoxic payload, independent of the antigen that is targeted and/or the type of cancer that is treated. DLTs are commonly associated with cells and tissues that do not express the targeted antigen (i.e., off-target toxicity), and often limit ADC dosage to levels below those required for optimal anti-cancer effects. In this manuscript, we review the fundamental mechanisms contributing to ADC toxicity, we summarize common ADC treatment-related adverse events, and we discuss several approaches to mitigating ADC toxicity.

Combinational therapies for the treatment of advanced cervical cancer

INTRODUCTION

From a therapeutic standpoint, invasive cervical cancer can be designated as early, locally advanced, and advanced stages. Systemic treatment remains the primary therapeutical modality for advanced cervical cancer patients who are not candidates for local curative treatments (surgery and radiation).

AREAS COVERED

In this review, the author discusses recent clinical studies published in PubMed on the treatment of advanced cervical carcinoma. The author also provides his expert perspectives on the current state of play.

EXPERT OPINION

Survival outcomes for advanced cervical cancer patients have been steadily improving since 1981, when single-agent cisplatin was adopted as the standard of care. In 2014, bevacizumab increased median overall survival (MOS) to 17 months when combined with standard chemotherapy (platinum-paclitaxel). In 2021, the checkpoint inhibitor (CPI) pembrolizumab, when used in the first line added to platinum-paclitaxel-bevacizumab, increased mOS to 24 months. Two other CPIs are in phase III trials as first-line treatments. As for second-line therapy, cemiplimab has shown increased survival compared to single-agent chemotherapy, and a phase III trial with tisotumab vedotin is currently ongoing. Nevertheless, there is still an unmet need for new more effective treatments and significant efforts are needed in the discovery of drugs for advanced cervical cancer beyond the current 'me-too' drugs.

Towards Novel Gene and Cell Therapy Approaches for Cervical Cancer

Cervical cancer is one of the most common malignancies in women, and the majority of cases are caused by infection with high-risk human papilloma virus (HPV) subtypes. Despite effective preventative measures, such as vaccinations against HPV, over 300,000 women die world-wide from cervical cancer each year. Once cervical cancer is diagnosed, treatment may consist of radial hysterectomy, or chemotherapy and radiotherapy, or a combination of therapies dependent upon the disease stage. Unfortunately, overall prognosis for patients with metastatic or recurrent disease remains poor. In these cases, immunotherapies may be useful based on promising preclinical work, some of which has been successfully translated to the clinic. For example, approaches using monoclonal antibodies directed against surface proteins important for control of immune checkpoints (i.e., immune checkpoint inhibitors) were shown to improve outcome in many cancer settings, including cervical cancer. Additionally, initial clinical studies showed that application of cytotoxic immune cells modified to express chimeric antigen receptors (CAR) or T cell receptors (TCR) for better recognition and elimination of tumor cells may be useful to control cervical cancer. This review explores these important topics, including strengths and limitations of standard and developing approaches, and how some novel treatment strategies may be optimally used to offer the best possible treatment for cervical cancer patients.

Recent Advancement in Anticancer Compounds from Marine Organisms: Approval, Use and Bioinformatic Approaches to Predict New Targets

In recent years, the study of anticancer bioactive compounds from marine sources has received wide interest. Contextually, world regulatory authorities have approved several marine molecules, and new synthetic derivatives have also been synthesized and structurally improved for the treatment of numerous forms of cancer. However, the administration of drugs in cancer patients requires careful evaluation since their interaction with individual biological macromolecules, such as proteins or nucleic acids, determines variable downstream effects. This is reflected in a constant search for personalized therapies that lay the foundations of modern medicine. The new knowledge acquired on cancer mechanisms has certainly allowed advancements in tumor prevention, but unfortunately, due to the huge complexity and heterogeneity of cancer, we are still looking for a definitive therapy and clinical approaches. In this review, we discuss the significance of recently approved molecules originating from the marine environment, starting from their organism of origin to their structure and mechanism of action. Subsequently, these bio-compounds are used as models to illustrate possible bioinformatics approaches for the search of new targets that are useful for improving the knowledge on anticancer therapies.

A review of recent advances on single use of antibody-drug conjugates or combination with tumor immunology therapy for gynecologic cancer

Immune checkpoint inhibitors have made significant progress in the treatment of various cancers. However, due to the low ICI responsive rate for the gynecologic cancer, ICI two-drug combination therapy tends to be a predominant way for clinical treatment. Antibody-drug conjugates, a promising therapeutic modality for cancer, have been approved by the FDA for breast cancer, lymphoma, multiple myeloma and gastric cancer. On September 2021, the FDA granted accelerated approval to tisotumab vedotin for patients with recurrent or metastatic cervical cancer. Currently, the role of therapy of ADCs on gynecologic tumors was also included in medication regimens. Now more than 30 ADCs targeting for 20 biomarkers are under clinical trials in the field, including monotherapy or combination with others for multiple lines of therapy. Some ADCs have been proved to enhance the antitumor immunity effect on both pre-clinical models and clinical trials. Therefore, combination of ADCs and ICIs are expected in clinical trials. In this review, we discuss current development of ADCs in gynecologic oncology and the combination effects of ICIs and ADCs.

First-in-Humans PET Imaging of Tissue Factor in Patients with Primary and Metastatic Cancers Using 18F-labeled Active-Site Inhibited Factor VII (18F-ASIS): Potential as Companion Diagnostic

Tissue factor (TF) expression in cancers correlates with poor prognosis. Recently, the first TF-targeted therapy was approved by the U.S. Food and Drug Administration for cervical cancer. To unfold the potential of TF-targeted therapies, correct stratification and selection of patients eligible for treatments may become important for optimization of patient outcomes. TF-targeted PET imaging based on ¹⁸F-radiolabeled active-site inhibited versions of the TF natural ligand coagulation factor VII (¹⁸F-ASIS) has in preclinical models convincingly demonstrated its use for noninvasive quantitative measurements of TF expression in tumor tissue. ¹⁸F-ASIS PET imaging thus has the potential to act as a diagnostic companion for TF-targeted therapies in the clinical setting. Methods: In this first-in-humans trial, we included 10 cancer patients (4 pancreatic, 3 breast, 2 lung, and 1 cervical cancer) for ¹⁸F-ASIS PET imaging. The mean and SD of administered ¹⁸F-ASIS activity was 157 ± 35 MBq (range, 93-198 MBq). PET/CT was performed after 1, 2, and 4 h. The primary objectives were to establish the safety, biodistribution, pharmacokinetics, and dosimetry of ¹⁸F-ASIS. Secondary objectives included quantitative measurements of SUVs in tumor tissue with PET and evaluation of the correlation (Pearson correlation) between tumor SUV_max and ex vivo TF expression in tumor tissue. Results: Administration of ¹⁸F-ASIS was safe, and no adverse events were observed. No clinically significant changes in vital signs, electrocardiograms, or blood parameters were observed after injection of ¹⁸F-ASIS. Mean ¹⁸F-ASIS plasma half-life was 3.2 ± 0.6 h, and the radiotracer was predominantly excreted in the urine. For injection activity of 200 MBq of ¹⁸F-ASIS, effective whole-body dose was 4 mSv and no prohibitive organ-specific absorbed doses were found. Heterogeneous radiotracer uptake was observed across patients and within tumors. We found a trend of a positive correlation between tumor SUV_max and ex vivo TF expression (r = 0.84, P = 0.08, n = 5). Conclusion: ¹⁸F-ASIS can be safely administered to cancer patients for PET imaging of TF expression in tumors. The trial marks the first test of a TF-targeted PET radiotracer in humans (first-in-class). The findings represent important first steps toward clinical implementation of ¹⁸F-ASIS PET imaging of TF expression.

Clinical best practices in optimal monitoring, early diagnosis, and effective management of antibody-drug conjugate-induced interstitial lung disease or pneumonitis: a multidisciplinary team approach in Singapore

INTRODUCTION

Interstitial lung disease (ILD) or pneumonitis remains an important adverse event identified with treatment with antibody-drug conjugates (ADCs). Drug-induced ILD (DILD) accounts for 3%-5% of common ILD cases and is a significant problem in clinical practice. Hence, with the anticipation of the widespread use of ADCs, it will be important for guidelines and recommendations to be established to direct and standardize the management of DILD by a multidisciplinary team (MDT).

AREAS COVERED

A thorough literature search was conducted using PubMed to identify relevant articles related to ADCs published between 1 January 2010 and 31 November 2022. Based on the review of the literature combined with expert opinions, this review article offers an overview of incidences of ILDs associated with the use of newer anticancer therapies, specifically ADCs, and discusses local-regional best practices in optimal monitoring, early diagnosis, and management of DILD involving an MDT.

EXPERT OPINION

Multidisciplinary input and consensus are crucial in the accurate diagnosis of DILD. The core group of essential attendees in the MDT are oncologists, pulmonologists, thoracic radiologists, and pathologists. This allows for the integration of expertise from different specialists to achieve a 'best fit' diagnosis and management.

Facts and Hopes in Immunotherapy of Endometrial Cancer

Immunotherapy with checkpoint inhibitors has changed the paradigm of treatment for many tumors, and endometrial carcinoma is not an exception. Approved treatment options are pembrolizumab or dostarlimab for mismatch repair deficient tumors, pembrolizumab for tumors with high mutational load, and, more recently, pembrolizumab/lenvatinib for all patients with endometrial cancer. Endometrial cancer is a heterogeneous disease with distinct molecular subtypes and different prognoses. Differences between molecular subgroups regarding antigenicity and immunogenicity should be relevant to develop more tailored immunotherapeutic approaches. In this review, we aim to summarize and discuss the current evidence-Facts, and future opportunities-Hopes-of immunotherapy for endometrial cancer, focusing on relevant molecular and tumor microenvironment features of The Cancer Genome Atlas endometrial cancer subtypes.

Population pharmacokinetic analysis for tisotumab vedotin in patients with locally advanced and/or metastatic solid tumors

Tisotumab vedotin is an investigational antibody-drug conjugate (ADC) for treatment of solid tumors expressing tissue factor with accelerated approval from the US Food and Drug Administration for treatment of recurrent or metastatic cervical cancer with disease progression during or after chemotherapy. This study describes development of a population pharmacokinetic (PK) model to assess the PK profile of tisotumab vedotin and microtubule-disrupting agent monomethyl auristatin E (MMAE) using data from 399 patients with solid tumors across four phase I/II trials. The ADC-MMAE model describes ADC and MMAE concentrations following intravenous administration of tisotumab vedotin. This four-compartment model comprises a two-compartment ADC model with parallel linear and Michaelis-Menten elimination, a delay compartment, and a one-compartment MMAE model. Nonspecific linear clearance of ADC was 1.42 L/day, central volume of distribution (V_c ) was 3.10 L, and median terminal half-life of ADC was 4.04 days. Apparent clearance of MMAE was 42.8 L/day, and apparent volume of distribution was 2.09 L. Terminal slope of the MMAE concentration-time curve was defined by the delay compartment rate with a half-life of 2.56 days. Patients with higher body weight and lower albumin concentration had faster ADC clearance. Male patients and those with higher body weight and lower albumin concentration had higher V_c . Body weight was the most influential covariate influencing distribution and elimination of ADC and MMAE, thus supporting weight-based dosing of tisotumab vedotin. Presence of antidrug antibodies (detected in 3.3% of patients) did not affect key PK parameters or exposures for ADC and MMAE.

Recurrent or primary metastatic cervical cancer: current and future treatments

Despite screening programs for early detection and the approval of human papillomavirus vaccines, around 6% of women with cervical cancer (CC) are discovered with primary metastatic disease. Moreover, one-third of the patients receiving chemoradiation followed by brachytherapy for locally advanced disease will have a recurrence. At the end, the vast majority of recurrent or metastatic CC not amenable to locoregional treatments are considered incurable disease with very poor prognosis. Historically, cisplatin monotherapy, then a combination of cisplatin and paclitaxel were considered the standard of care. Ten years ago, the addition of bevacizumab to chemotherapy demonstrated favorable data in terms of response rate and overall survival. Even with this improvement, novel therapies are needed for the treatment of recurrent CC in first as well as later lines. In the last decades, a better understanding of the interactions between human papillomavirus infection and the host immune system response has focused interest on the use of immunotherapeutic drugs in CC patients. Indeed, immune checkpoint inhibitors (pembrolizumab, cemiplimab, and others) have recently emerged as novel therapeutic pillars that could provide durable responses with impact on overall survival in patients in the primary (in addition to chemotherapy) or recurrent (monotherapy) settings. Tisotumab vedotin, an antibody-drug conjugate targeting the tissue factor, is another emerging drug. Several trials in monotherapy or in combination with immunotherapy, chemotherapy, or bevacizumab showed very promising results. There is a high need for more potent biomarkers to better accurately determine which patients would receive the greatest benefit from all these aforementioned drugs, but also to identify patients with specific molecular characteristics that could benefit from other targeted therapies. The Cancer Genome Atlas Research Network identified several genes significantly mutated, potentially targetable. These molecular data have highlighted the molecular heterogeneity of CC.

Antibody-Drug Conjugates for Melanoma and Other Skin Malignancies

OPINION STATEMENT

While most skin malignancies are successfully treated with surgical excision, advanced and metastatic skin malignancies still often have poor long-term outcomes despite therapeutic advances. Antibody-drug conjugates (ADCs) serve as a potentially promising novel therapeutic approach to treat advanced skin cancers as they combine antibody-associated antigen specificity with cytotoxic anti-tumor effects, thereby maximizing efficacy and minimizing systemic toxicity. While no ADCs have gained regulatory approval for advanced skin cancers, several promising agents are undergoing preclinical and clinical investigation. In addition to identifying and validating skin cancer antigen targets, the key to maximizing therapeutic success is the careful development of each component of the ADC complex: antibodies, cytotoxic drugs, and linkers. It is the optimization of each of these components that will be integral in overcoming resistance, maximizing safety, and improving long-term clinical outcomes.

A Review of Tisotumab Vedotin-tftv in Recurrent or Metastatic Cervical Cancer

OBJECTIVE

To evaluate the safety and efficacy of tisotumab vedotin-tftv (TV), a first-in-class vectorized anti-tissue factor (TF) antibody-drug conjugate (ADC), for the treatment of recurrent or metastatic cervical cancer.

DATA SOURCES

A literature search of ClinicalTrials.gov, Embase, and PubMed was conducted using the terms tisotumab vedotin AND cervical cancer from inception to June 30, 2022.

STUDY SELECTION AND DATA EXTRACTION

All applicable publications, package inserts, meeting abstracts, and clinical trials involving TV in the treatment of cervical cancer were reviewed.

DATA SYNTHESIS

TV is a fully human TF-specific monoclonal antibody conjugated to monomethyl auristatin E, which serves as a highly potent cytotoxic payload. In the pivotal phase II InnovaTV 204 clinical trial, TV demonstrated an objective response rate of 24% (95% confidence interval [CI], 16%-33%). The mean duration of response was 8.3 months. Common toxicities included abdominal pain, alopecia, conjunctivitis, constipation, decreased appetite, diarrhea, dry eye, epistaxis, nausea/vomiting, and peripheral neuropathy. Unique and/or serious adverse events warranting careful monitoring include ocular complications, hemorrhaging, peripheral neuropathies, fetal-embryo toxicity, pneumonitis, and immunogenicity.

RELEVANCE TO PATIENT CARE AND CLINICAL PRACTICE

Recurrent or metastatic cervical cancer remains a high-risk disease with limited treatment options. Using ADCs to target tumors with aberrant expression of TF appears to be a viable treatment strategy.

CONCLUSIONS

TV is the first Food and Drug Administration-approved TF-directed ADC. With a manageable safety profile and promising anticancer activity, TV warrants consideration as a novel targeted agent for the treatment of recurrent or metastatic cervical cancer. Further studies are required to determine the optimal place in therapy for TV.

Regulation of Tissue Factor by CD44 Supports Coagulant Activity in Breast Tumor Cells

Simple Summary

Metastasis and thromboembolic complications are the main cause of cancer-associated death. An overexpression of coagulation factors, and particularly Tissue factor, by tumor cells is a key event implicated in this observed hypercoagulability. Tissue Factor is indeed a cellular initiator of the coagulation cascade which has been associated with aggressive tumor phenotypes such as those characteristic of Epithelial-Mesenchymal Transitions (EMTs) and Cancer Stem Cells (CSCs). Understanding molecular mechanisms controlling Tissue Factor overexpression in those tumor phenotypes is thus an important aspect of cancer research. We show here that CD44 (a transmembrane marker of CSC and EMT phenotypes) contributes to regulate TF expression at a transcriptional level, thereby supporting procoagulant properties in tumor cells that facilitate their metastatic spread.

Abstract

Previous work identified Tissue Factor (TF), a key activator of the coagulation cascade, as a gene induced in cellular contexts of Epithelial-Mesenchymal Transitions (EMTs), providing EMT⁺ Circulating Tumor Cells (CTCs) with coagulant properties that facilitate their metastatic seeding. Deciphering further molecular aspects of TF regulation in tumor cells, we report here that CD44 and TF coexpress in EMT contexts, and that CD44 acts as a regulator of TF expression supporting procoagulant properties and metastatic seeding. A transcriptional regulatory mechanism bridging CD44 to TF expression was further evidenced. Comparing different TF –promoter luciferase reporter constructs, we indeed found that the shortest -111 pb TF promoter fragment harboring three Specificity Protein 1 (Sp1) binding sites is still responsive to CD44 silencing. The observation that (i) mutation within Sp1 binding sites decreased the basal activity of the -111 pb TF promoter construct, (ii) CD44 silencing decreased Sp1 protein and mRNA levels and (iii) Sp1 silencing diminished TF expression further points to Sp1 as a key mediator linking CD44 to TF regulation. All together, these data thus report a transcriptional regulatory mechanism of TF expression by CD44 supporting procoagulant activity and metastatic competence of CTCs.

Tissue factor: a neglected role in cancer biology

Tissue factor (TF), an initiator of extrinsic coagulation pathway, is positively correlated with venous thromboembolism (VTE) of tumor patients. Beyond thrombosis, TF plays a vital role in tumor progression. TF is highly expressed in cancer tissues and circulating tumor cell (CTC), and activates factor VIIa (FVIIa), which increases tumor cells proliferation, angiogenesis, epithelial-mesenchymal transition (EMT) and cancer stem cells(CSCs) activity. Furthermore, TF and TF-positive microvesicles (TF⁺MVs) activate the coagulation system to promote the clots formation with non-tumor cell components (e.g., platelets, leukocytes, fibrin), which makes tumor cells adhere to clots to form CTC clusters. Then, tumor cells utilize clots to cause its reducing fluid shear stress (FSS), anoikis resistance, immune escape, adhesion, extravasation and colonization. Herein, we review in detail that how TF signaling promotes tumor metastasis, and how TF-targeted therapeutic strategies are being in the preclinical and clinical trials.

Research Trend of Publications Concerning Antibody-Drug Conjugate in Solid Cancer: A Bibliometric Study

Background: Antibody-drug conjugate (ADC) is a promising therapy for solid cancer that has raised global concern. Although several papers have reviewed the current state of ADCs in different solid cancers, a quantitative analysis of the publications in this field is scarce.

Methods: Publications related to ADC in the field of solid cancer were obtained from the Web of Science Core Collection. Data analyses were performed with VOSviewer 1.6.9, HistCite 2.1, CiteSpace V and R package Bibliometrix.

Results: A total of 3,482 records were obtained in the holistic field and 1,197 in the clinical field. Steady growth in the number of publications was observed. The United States was the leading contributor in this field. Krop IE was the most influential author. The most productive institution was Genentech Inc., while Mem Sloan Kettering Canc Ctr was the most cited one. The most impactful journal was the Journal of Clinical Oncology. A total of 37 burst references and five burst references were identified between 2017–2022 in the holistic and clinical fields, respectively. Keywords analysis indicated that ADCs research mainly involved breast cancer, triple-negative breast cancer, ovarian cancer, small cell lung cancer, prostate cancer, gastric cancer, and urothelial carcinoma. ADC agents including trastuzumab emtansine, trastuzumab deruxtecan, sacituzumab govitecan, enfortumab vedotin, and rovalpituzumab tesirine were highly studied. Targets including HER2, trophoblast cell-surface antigen, mesothelin, delta-like ligand 3, and nectin-4 were the major concerns.

Conclusion: This study analyzed publications concerning ADCs in the field of solid cancer with bibliometric analysis. Further clinical trials of ADCs and designs of the next generation of ADCs are the current focuses of the field. Acquired resistance of ADCs and biomarkers for ADC therapy efficacy monitoring are future concerns.

A novel strategy for treatment of bladder cancer: Antibody-drug conjugates

In the past, there was no second-line chemotherapeutic agent suitable for use when urothelial carcinoma (UC) progressed to platinum-resistant UC. However, recently, several new treatment options, such as immune checkpoint inhibitors or targeted therapy have shifted the treatment paradigm regarding second-line therapeutic modalities. A novel class of therapeutic agents includes an antibody-drug conjugate (ADC). ADCs consist of three characteristics: a monoclonal antibody, linker, and payload. The specificity of the monoclonal antibody facilitates the delivery of a linked cytotoxic drug directly into the target tumor cell. Although various ADCs have been developed and approved for use in treating several solid tumors, almost all ADCs for the treatment of UC are still in the testing phase. Here, we review the key points about ADCs and summarize the novel ADCs that are approved or are involved in ongoing studies in UC.

Antibody-Drug Conjugates in Uro-Oncology

Currently available treatment options for patients with refractory metastatic prostate, bladder, or kidney cancers are limited with the prognosis remaining poor. Advances in the pathobiology of tumors has led to the discovery of cancer antigens that may be used as the target for cancer treatment. Antibody-drug conjugates (ADCs) are a relatively new concept in cancer treatment that broaden therapeutic landscape. ADCs are examples of a 'drug delivery into the tumor' system composed of an antigen-directed antibody linked to a cytotoxic drug that may release cytotoxic components after binding to the antigen located on the surface of tumor cells. The clinical properties of drugs are influenced by every component of ADCs. Regarding uro-oncology, enfortumab vedotin (EV) and sacituzumab govitecan (SG) are currently registered for patients with locally advanced or metastatic urothelial cancer following previous treatment with an immune checkpoint inhibitor (iCPI; programmed death receptor-1 [PD-1] or programmed death-ligand 1 [PD-L1]) inhibitor) and platinum-containing chemotherapy. The EV-301 trial showed that EV significantly prolonged the overall survival compared with classic chemotherapy. The TROPHY-U-01 trial conducted to evaluate SG demonstrated promising results as regards the objective response rate and duration of response. The safety and efficacy of ADCs in monotherapy and polytherapy (mainly with iCPIs) for different cancer stages and tumor types are assessed in numerous ongoing clinical trials. The aim of this review is to present new molecular biomarkers, specific mechanisms of action, and ongoing clinical trials of ADCs in genitourinary cancers. In the expert discussion, we assess the place of ADCs in uro-oncology and discuss their clinical value.

Targeted treatment options for the management of metastatic/persistent and recurrent cervical cancer

INTRODUCTION

Cervical cancer is the overall fourth most common malignancy and the fourth most common cause of cancer related deaths worldwide. Despite vaccination and screening programs, many women continue to present with advanced stage cervical cancer, wherein the treatment options have been limited.

AREAS COVERED

In this review, immunotherapy and the potential targeted therapies that have demonstrated promise in the treatment of persistent, recurrent, and metastatic cervical cancer are discussed.

EXPERT OPINION

Our global goal in the gynecologic oncology community is to eliminate cervical cancer, by increasing the uptake of preventive vaccination and screening programs. For unfortunate patients who present with metastatic, persistent, and recurrent cervical cancer, pembrolizumab with chemotherapy, with or without bevacizumab is the new first line therapy for PD-L1 positive patients. For this patient population as a second line therapy, tisotumab vedotin (i.e. ADC) has shown significant efficacy in Phase II trials, leading to FDA approval. Combination regimens inclusive of immune checkpoint inhibitors, DNA damage repair inhibitors, antibody drug conjugates are potential breakthrough treatment strategies and are currently being investigated.

Therapeutic Strategies Focused on Cancer-Associated Hypercoagulation for Ovarian Clear Cell Carcinoma

Ovarian clear cell carcinoma (OCCC) is associated with chemotherapy resistance and poor prognosis, especially in advanced cases. Although comprehensive genomic analyses have clarified the significance of genomic alterations such as ARID1A and PIK3CA mutations in OCCC, therapeutic strategies based on genomic alterations have not been confirmed. On the other hand, OCCC is clinically characterized by a high incidence of thromboembolism. Moreover, OCCC specifically shows high expression of tissue factor and interleukin-6, which play a critical role in cancer-associated hypercoagulation and may be induced by OCCC-specific genetic alterations or the endometriosis-related tumor microenvironment. In this review, we focused on the association between cancer-associated hypercoagulation and molecular biology in OCCC. Moreover, we reviewed the effectiveness of candidate drugs targeting hypercoagulation, such as tissue factor- or interleukin-6-targeting drugs, anti-inflammatory drugs, anti-hypoxia signaling drugs, anticoagulants, and combined immunotherapy with these drugs for OCCC. This review is expected to contribute to novel basic research and clinical trials for the prevention, early detection, and treatment of OCCC focused on hypercoagulation.

A novel risk score model based on five angiogenesis-related long non-coding RNAs for bladder urothelial carcinoma

Background

Tumour angiogenesis is an independent risk factor for bladder urothelial carcinoma (BUC) progression, but viable and promising antiangiogenic targets are understudied. Emerging evidence suggests that long non-coding RNAs (lncRNAs) play prominent role in the tumour microenvironment and tumour angiogenesis.

Methods

The clinical data of BUC patients were obtained from TCGA database and clinical specimens of 138 BUC patients. Univariate and multivariate COX regression analyses were used to identify survival-related ARLNRs (sARLNRs) from The Molecular Signatures Database v4.0. Fisher’s exact probability method was used to detect the correlations between sARLNRs levels and clinicopathological characteristics. A chain of experiments including FACS, qPCR, immunohistochemistry, tube formation, migration and invasion assays, combining with co-culture models, were utilized to validate the clinical significance and angiogenetic correlation of sARLNRs.

Results

Five sARLNRs were employed to establish an angiogenesis-related risk score model, by which patients in the low-risk group obtained better overall survival than those in the high-risk group. The expression of AC005625.1 and AC008760.1 was significantly related to ECs percentage, tumour size and muscle invasion status. Besides, AC005625.1 and AC008760.1 expressed lower in BUC cell lines and tumour tissues than that in normal urothelial cells and adjacent normal tissues, with much lower levels in more advanced T stages. A prominently higher proportion of ECs was detected in tumour tissues with lower expression of AC005625.1 and AC008760.1. In the co-culture models, we found that knockdown of AC005625.1 and AC008760.1 in BUC cells increased the tube formation, migration and invasion abilities of HUVEC. The expression levels of CD31, VEGF-A, VIMENTIN and N-CADHERIN were also enhanced in HUVEC cells co-cultured with siR-AC005625.1 and siR-AC008760.1-treated T24 cells.

Conclusion

In the study, we identify five sARLNRs and validate their clinical significance, angiogenesis correlation and prognosis-predictive values in BUC. These findings may provide a new perspective and some promising antiangiogenic targets for clinical diagnosis and treatment strategies of BUC.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12935-022-02575-1.

Advancing antibody-drug conjugates in gynecological malignancies: myth or reality?

Antibody-drug conjugates (ADCs) represent a new class of therapeutic agents designed to target specific antigens on tumor cells, combining the specificity of monoclonal antibodies to the cytotoxicity of classic chemotherapy agents. These drugs have been extensively studied both in solid and hematologic malignancies, leading to substantial improvement in the therapeutic landscape for several tumors. Despite no ADC have been yet approved for the treatment of gynecological malignancies, some agents have shown promising results and might have the potential to become part of the standard of care. Among them, mirvetuximab soravtansine has shown activity in platinum-resistant ovarian cancer with high folate-α receptor expression, as a single agent and in combination. Tisotumab vedotin is active in patients with pre-treated cervical cancer, and further investigation is ongoing. The purpose of this review is to summarize the structural and functional characteristics of ADCs and analyze the most recent and promising data regarding the clinical development of ADCs in gynecological malignancies. The available data on the efficacy of the more studied ADCs in ovarian, endometrial, and cervical cancers will be discussed along with toxicities of special interest, the mechanisms of resistance, and future possible drugs combination.

Characterization of a novel bispecific antibody targeting tissue factor-positive tumors with T cell engagement

T cell engaging bispecific antibody (TCB) is an effective immunotherapy for cancer treatment. Through co-targeting CD3 and tumor-associated antigen (TAA), TCB can redirect CD3⁺ T cells to eliminate tumor cells regardless of the specificity of T cell receptor. Tissue factor (TF) is a TAA that involved in tumor progression. Here, we designed and characterized a novel TCB targeting TF (TF-TCB) for the treatment of TF-positive tumors. In vitro, robust T cell activation, tumor cell lysis and T cell proliferation were induced by TF-TCB. The tumor cell lysis activity was dependent upon both CD3 and TF binding moieties of the TF-TCB, and was related to TF expression level of tumor cells. In vivo, in both tumor cell/human peripheral blood mononuclear cells (PBMC) co-grafting model and established tumor models with poor T cell infiltration, tumor growth was strongly inhibited by TF-TCB. T cell infiltration into tumors was induced during the treatment. Furthermore, efficacy of TF-TCB was further improved by combination with immune checkpoint inhibitors. For the first time, our results validated the feasibility of using TF as a target for TCB and highlighted the potential for TF-TCB to demonstrate efficacy in solid tumor treatment.

Antibody drug conjugate: the "biological missile" for targeted cancer therapy

Antibody-drug conjugate (ADC) is typically composed of a monoclonal antibody (mAbs) covalently attached to a cytotoxic drug via a chemical linker. It combines both the advantages of highly specific targeting ability and highly potent killing effect to achieve accurate and efficient elimination of cancer cells, which has become one of the hotspots for the research and development of anticancer drugs. Since the first ADC, Mylotarg® (gemtuzumab ozogamicin), was approved in 2000 by the US Food and Drug Administration (FDA), there have been 14 ADCs received market approval so far worldwide. Moreover, over 100 ADC candidates have been investigated in clinical stages at present. This kind of new anti-cancer drugs, known as "biological missiles", is leading a new era of targeted cancer therapy. Herein, we conducted a review of the history and general mechanism of action of ADCs, and then briefly discussed the molecular aspects of key components of ADCs and the mechanisms by which these key factors influence the activities of ADCs. Moreover, we also reviewed the approved ADCs and other promising candidates in phase-3 clinical trials and discuss the current challenges and future perspectives for the development of next generations, which provide insights for the research and development of novel cancer therapeutics using ADCs.

Antibody-Drug Conjugate Targets, Drugs and Linkers

Antibody-drug conjugates offer the possibility of directing powerful cytotoxic agents to a malignant tumor while sparing normal tissue. The challenge is to select an antibody target expressed exclusively or at highly elevated levels on the surface of tumor cells and either not all or at low levels on normal cells. The current review explores 78 targets that have been explored as antibody-drug conjugate targets. Some of these targets have been abandoned, 9 or more are the targets of FDA-approved drugs, and most remain active clinical interest. Antibody-drug conjugates require potent cytotoxic drug payloads, several of these small molecules are discussed, as are the linkers between the protein component and small molecule components of the conjugates. Finally, conclusions regarding the elements for the successful antibody-drug conjugate are discussed.

Antibody–Drug Conjugates as an Emerging Therapy in Oncodermatology

Simple Summary

Currently, the therapeutic arsenal to fight cancers is extensive. Among these, antibody–drug conjugates (ADCs) consist in an antibody linked to a cytotoxic agent, allowing a specific delivery to tumor cells. ADCs are an emerging class of therapeutics, with twelve FDA- and EMA-approved drugs for hematological and solid cancers. In recent years, tremendous progress has been observed in therapeutic approaches for advanced skin cancer patients. ADCs appear as an emerging therapeutic option in oncodermatology. After providing an overview of ADC design and development, the goal of this article is to review the potential ADC indications in the field of oncodermatology.

Abstract

Antibody–drug conjugates (ADCs) are an emerging class of therapeutics, with twelve FDA- and EMA-approved drugs for hematological and solid cancers. Such drugs consist in a monoclonal antibody linked to a cytotoxic agent, allowing a specific cytotoxicity to tumor cells. In recent years, tremendous progress has been observed in therapeutic approaches for advanced skin cancer patients. In this regard, targeted therapies (e.g., kinase inhibitors) or immune checkpoint-blocking antibodies outperformed conventional chemotherapy, with proven benefit to survival. Nevertheless, primary and acquired resistances as well as adverse events remain limitations of these therapies. Therefore, ADCs appear as an emerging therapeutic option in oncodermatology. After providing an overview of ADC design and development, the goal of this article is to review the potential ADC indications in the field of oncodermatology.

A Small Molecule–Drug Conjugate (SMDC) Consisting of a Modified Camptothecin Payload Linked to an αVß3 Binder for the Treatment of Multiple Cancer Types

To improve tumor selectivity of cytotoxic agents, we designed VIP236, a small molecule–drug conjugate consisting of an αVβ3 integrin binder linked to a modified camptothecin payload (VIP126), which is released by the enzyme neutrophil elastase (NE) in the tumor microenvironment (TME). The tumor targeting and pharmacokinetics of VIP236 were studied in tumor-bearing mice by in vivo near-infrared imaging and by analyzing tumor and plasma samples. The efficacy of VIP236 was investigated in a panel of cancer cell lines in vitro, and in MX-1, NCI-H69, and SW480 murine xenograft models. Imaging studies with the αVβ3 binder demonstrated efficient tumor targeting. Administration of VIP126 via VIP236 resulted in a 10-fold improvement in the tumor/plasma ratio of VIP126 compared with VIP126 administered alone. Unlike SN38, VIP126 is not a substrate of P-gp and BCRP drug transporters. VIP236 presented strong cytotoxic activity in the presence of NE. VIP236 treatment resulted in tumor regressions and very good tolerability in all in vivo models tested. VIP236 represents a novel approach for delivering a potent cytotoxic agent by utilizing αVβ3 as a targeting moiety and NE in the TME to release the VIP126 payload—designed for high permeability and low efflux—directly into the tumor stroma.

Antibody-drug conjugates: Resurgent anticancer agents with multi-targeted therapeutic potential

Antibody-drug conjugates (ADCs) constitute a relatively new group of anticancer agents, whose first appearance took place about two decades ago, but a renewed interest occurred in recent years, following the success of anti-cancer immunotherapy with monoclonal antibodies. Indeed, an ADC combines the selectivity of a monoclonal antibody with the cell killing properties of a chemotherapeutic agent (payload), joined together through an appropriate linker. The antibody moiety targets a specific cell surface antigen expressed by tumor cells and/or cells of the tumor microenvironment and acts as a carrier that delivers the cytotoxic payload within the tumor mass. Despite advantages in terms of selectivity and potency, the development of ADCs is not devoid of challenges, due to: i) low tumor selectivity when the target antigens are not exclusively expressed by cancer cells; ii) premature release of the cytotoxic drug into the bloodstream as a consequence of linker instability; iii) development of tumor resistance mechanisms to the payload. All these factors may result in lack of efficacy and/or in no safety improvement compared to unconjugated cytotoxic agents. Nevertheless, the development of antibodies engineered to remain inert until activated in the tumor (e.g., antibodies activated proteolytically after internalization or by the acidic conditions of the tumor microenvironment) together with the discovery of innovative targets and cytotoxic or immunomodulatory payloads, have allowed the design of next-generation ADCs that are expected to possess improved therapeutic properties. This review provides an overview of approved ADCs, with related advantages and limitations, and of novel targets exploited by ADCs that are presently under clinical investigation.

Revisiting antibody-drug conjugates and their predictive biomarkers in platinum-resistant ovarian cancer

Until to date, platinum derived drugs are still the backbone of treating ovarian cancer (OC). Most patients treated with platinum-based chemotherapy develop resistance during the course of their management. The treatment of platinum-resistant ovarian cancer (PROC) is challenging. Few therapeutic options are available for patients with this aggressive disease. Besides, there are liminal advances regarding new anticancer drugs as well as validated predictive biomarkers of clinical outcomes in this setting. The enrollment of PROC patients in interventional studies is limited as compared to newly launched clinical trials for platinum-sensitive OC. Enthusiastically, the emergence of antibody-drug conjugates (ADCs) has provided promising findings for further clinical development in PROC. ADCs have the advantage to selectively deliver cytotoxic drugs to cancer cells expressing several of antigens using specific monoclonal antibodies based on the concept of immune bioconjugation. This innovative class of therapeutics showed encouraging early signs of clinical efficacy in PROC particularly mirvetuximab soravtansine that has been successfully introduced into three randomized and controlled phase III studies. In this review, the evidence from clinical trials supporting the development of ADCs targeting folate receptor alpha, sodium-dependent phosphate transporter 2B, dipeptidase 3, mesothelin, mucin 16, and tissue factor using various cytotoxic payloads in PROC is reviewed.

Tisotumab Vedotin: First Approval

Tisotumab vedotin (Tivdak™) is an antibody-drug conjugate comprising a fully human monoclonal antibody specific for tissue factor (TF-011) conjugated to monomethyl auristatin E (MMAE) that has been engineered to target tissue factor expressing tumours. Based on the results of a phase II trial, tisotumab vedotin has been granted accelerated approval in the USA for the treatment of adult patients with recurrent or metastatic cervical cancer with disease progression on or after chemotherapy. This article summarizes the milestones in the development of tisotumab vedotin leading to this first approval.

Emerging targeted drug delivery strategies toward ovarian cancer

Ovarian cancer is a high-mortality malignancy in women. The contemporary clinical chemotherapy with classic cytotoxic drugs, targeted molecular inhibitors would mostly fail when ovarian cancer cells become drug-resistant or metastasize through the body or when patients bare no more toleration because of strong adverse effects. The past decade has spotted varying targeted delivery systems including antibody-drug conjugates (ADCs), peptide/folate/aptamer-drug conjugates, polymer-drug conjugates, ligand-functionalized nanomedicines, and dual-targeted nanomedicines that upgrade ovarian cancer chemo- and molecular therapy effectively in preclinical/clinical settings via endowing therapeutic agents selectivity and bypassing drug resistance as well as lessening systemic toxicity. The targeted delivery approaches further provide means to potentiate emergent treatment modalities such as molecular therapy, gene therapy, protein therapy, photodynamic therapy, dual-targeting therapy and combination therapy for ovarian cancer. This review highlights up-to-date development of targeted drug delivery strategies toward advanced, metastatic, relapsed, and drug resistant ovarian cancers.

Antibody-Antineoplastic Conjugates in Gynecological Malignancies: Current Status and Future Perspectives

In the last decade, antibody-drug conjugates (ADCs), normally formed by a humanized antibody and a small drug via a chemical cleavable or non-cleavable linker, have emerged as a potential treatment strategy in cancer disease. They allow to get a selective delivery of the chemotherapeutic agents at the tumor level, and, consequently, to improve the antitumor efficacy and, especially to decrease chemotherapy-related toxicity. Currently, nine antibody-drug conjugate-based formulations have been already approved and more than 80 are under clinical trials for the treatment of several tumors, especially breast cancer, lymphomas, and multiple myeloma. To date, no ADCs have been approved for the treatment of gynecological formulations, but many formulations have been developed and have reached the clinical stage, especially for the treatment of ovarian cancer, an aggressive disease with a low five-year survival rate. This manuscript analyzes the ADCs formulations that are under clinical research in the treatment of gynecological carcinomas, specifically ovarian, endometrial, and cervical tumors.

Functional Characteristics and Regulated Expression of Alternatively Spliced Tissue Factor: An Update

In human and mouse, alternative splicing of tissue factor's primary transcript yields two mRNA species: one features all six TF exons and encodes full-length tissue factor (flTF), and the other lacks exon 5 and encodes alternatively spliced tissue factor (asTF). flTF, which is oftentimes referred to as "TF", is an integral membrane glycoprotein due to the presence of an alpha-helical domain in its C-terminus, while asTF is soluble due to the frameshift resulting from the joining of exon 4 directly to exon 6. In this review, we focus on asTF-the more recently discovered isoform of TF that appears to significantly contribute to the pathobiology of several solid malignancies. There is currently a consensus in the field that asTF, while dispensable to normal hemostasis, can activate a subset of integrins on benign and malignant cells and promote outside-in signaling eliciting angiogenesis; cancer cell proliferation, migration, and invasion; and monocyte recruitment. We provide a general overview of the pioneering, as well as more recent, asTF research; discuss the current concepts of how asTF contributes to cancer progression; and open a conversation about the emerging utility of asTF as a biomarker and a therapeutic target.