Antibody-Drug Conjugates: Advancing from Magic Bullet to Biological Missile.

Precision drug development is focusing on targeting tumor cell surface proteins for therapeutic delivery, maximizing biomarker identified on-target damage to the tumor while minimizing toxicity. A recent article demonstrated high expression of B7-H4 antigen on resistant ovarian cancer cells and described preclinical activity of B7-H4-directed antibody-drug conjugate. See related article by Gitto et al., p. 1567.

Heterogeneity and treatment landscape of ovarian carcinoma.

Ovarian carcinoma is characterized by heterogeneity at the molecular, cellular and anatomical levels, both spatially and temporally. This heterogeneity affects response to surgery and/or systemic therapy, and also facilitates inherent and acquired drug resistance. As a consequence, this tumour type is often aggressive and frequently lethal. Ovarian carcinoma is not a single disease entity and comprises various subtypes, each with distinct complex molecular landscapes that change during progression and therapy. The interactions of cancer and stromal cells within the tumour microenvironment further affects disease evolution and response to therapy. In past decades, researchers have characterized the cellular, molecular, microenvironmental and immunological heterogeneity of ovarian carcinoma. Traditional treatment approaches have considered ovarian carcinoma as a single entity. This landscape is slowly changing with the increasing appreciation of heterogeneity and the recognition that delivering ineffective therapies can delay the development of effective personalized approaches as well as potentially change the molecular and cellular characteristics of the tumour, which might lead to additional resistance to subsequent therapy. In this Review we discuss the heterogeneity of ovarian carcinoma, outline the current treatment landscape for this malignancy and highlight potentially effective therapeutic strategies in development.

Mirvetuximab Soravtansine in Platinum-Resistant Ovarian Cancer.

Ovarian cancer is the second leading cause of death from gynecologic malignancies worldwide. Management of platinum-resistant disease is challenging and clinical outcomes with standard chemotherapy are poor. Over the past decades, significant efforts have been made to understand drug resistance and develop strategies to overcome treatment failure. Antibody drug conjugates (ADCs) are a rapidly growing class of oncologic therapeutics, which combine the ability to target tumor-specific antigens with the cytotoxic effects of chemotherapy. Mirvetuximab soravtansine is an ADC comprising an IgG1 monoclonal antibody against the folate receptor alpha (FRα) conjugated to the cytotoxic maytansinoid effector molecule DM4 that has shown promising clinical activity in patients with FR-α-positive ovarian cancer. This review summarizes current evidence of mirvetuximab soravtansine in platinum-resistant ovarian cancer, focusing on clinical activity, toxicity, and future directions.

Emerging peptide therapeutics for the treatment of ovarian cancer.

INTRODUCTION: The discovery of therapeutic proteomic targets has resulted in remarkable advances in oncology. Identification of functional and hallmark peptides in ovarian cancer can be leveraged for diagnostic and therapeutic targeting. These targets are expressed in different tumor cell locations, making them excellent candidates for theranostic imaging, precision therapeutics, and immunotherapy. The ideal target is homogeneously overexpressed in malignant cells with no expression in healthy cells, thereby avoiding off-tumor bystander toxicity. Several peptides are currently undergoing extensive evaluation for the development of vaccines, antibody-drug conjugates, monoclonal antibodies, radioimmunoconjugates, and cell therapy. AREAS COVERED: This review focuses on the significance of peptides as promising targets in ovarian cancer. English peer-reviewed articles and abstracts were searched in MEDLINE, PubMed, Embase, and major conference databases. EXPERT OPINION: Peptides and proteins expressed in tumor cells are an exciting area of research with great potential and may significantly influence precision therapeutics and immunotherapeutic strategies. Accurate utilization of peptide expression as a predictive biomarker has the potential to greatly enhance treatment precision. The ability to measure receptor expression paves the way for its use as a predictive biomarker for therapeutic targeting and requires critical validation of sensitivity and specificity for each indication to guide therapy.

Fighting resistance: post-PARP inhibitor treatment strategies in ovarian cancer.

Poly (ADP-ribose) polymerase inhibitors (PARPis) represent a therapeutic milestone in the management of epithelial ovarian cancer. The concept of 'synthetic lethality' is exploited by PARPi in tumors with defects in DNA repair pathways, particularly homologous recombination deficiency. The use of PARPis has been increasing since its approval as maintenance therapy, particularly in the first-line setting. Therefore, resistance to PARPi is an emerging issue in clinical practice. It brings an urgent need to elucidate and identify the mechanisms of PARPi resistance. Ongoing studies address this challenge and investigate potential therapeutic strategies to prevent, overcome, or re-sensitize tumor cells to PARPi. This review aims to summarize the mechanisms of resistance to PARPi, discuss emerging strategies to treat patients post-PARPi progression, and discuss potential biomarkers of resistance.

Taking the Road Less Traveled: Following Molecular Trail Markers.

Targeted therapy largely remains an unmet therapeutic need for low-grade serous ovarian carcinomas. However, recent advances in molecular characterization are beginning to change the landscape. A recent article highlights the association of genetic alterations with clinical outcomes, widening the scope of novel targeted therapies. See related article by Manning-Geist et al., p. 4456.