Introduction: COX-2 is a crucial enzyme in the manufacture of prostaglandins. The enzyme's metabolites might have an important function as regulators of the inflammatory response and other medical conditions such as cancer. Selective COX-2 inhibitors are believed to enhance or reverse the response of cancer chemotherapeutics.
Areas covered: This study addresses the chemical structures as well as the antitumor activity of new COX-2 inhibitors produced in the recent five years, aiming to provide an insight into the mechanism of COX-2 induced PGE2 powerful signal in cancer development.
Expert opinion: The significance of selective COX-2 inhibitors as an efficient superfamily of compounds with anti-inflammatory, anti-Alzheimer's, anti-Parkinson's disease, and anticancer properties has piqued the passion of academics in the field of drug development. Long-term usage of selective COX-2 inhibitors, such as celecoxib has been proven in clinical trials to lower the incidence of several human malignancies. Furthermore, celecoxib has the potential to greatly increase the effectiveness of chemotherapy. Our extensive understanding of selective COX-2 inhibitor SAR may aid in the development of safer and more effective selective COX-2 inhibitors as cancer chemopreventive agents. This review focuses on the different structural classes of selective COX-2 inhibitors, with a particular emphasis on their SAR.
Introduction: The sodium-glucose co-transporter 2 (SGLT2) inhibitors are FDA-approved class of drugs for diabetes management. They improve glycemic control by inducing glucosuria. Notwithstanding with potent anti-hyperglycemic activity, SGLT2 inhibitors are emerging as drugs with multifaceted therapeutic potential, evidenced for cardioprotective, renoprotective, antihypertensive, and neuroprotective activities. Continuous attempts are being accomplished through structural modification, development of new formulation, or combination with other drugs, to enhance the bioactivity spectrum of SGLT2 inhibitors for better management of diabetes and related complications.
Areas covered: This review comprises a summary of patent applications, acquired using the Espacenet Patent Search database, concerning SGLT2 inhibitors from 2019 to 2023, with focus on improving therapeutic potentials in management of diabetes and metabolic complications.
Expert opinion: SGLT2 inhibitors have provided an exciting treatment option for diabetes. Originally developed as anti-hyperglycemic agents, SGLT2 inhibitors exert pleiotropic metabolic responses and have emerged as promising antidiabetic agents with cardio-protective and reno-protective activities. Given their distinct therapeutic profile, SGLT2 inhibitors have revolutionized the management of diabetes and associated complications. Emerging evidences on their therapeutic potential against cancer, male reproductive dysfunctions, and neurodegenerative diseases indicate that further research in this field may unfold novel prospective on their plausible use in the management of other chronic conditions.
Introduction: Polo-like kinases (PLKs) have five isoforms, all of which play crucial roles in cell cycle and cell proliferation, offering opportunities for drug design and treatment of cancers and other related diseases. Notably, PLK1 and PLK4 have been extensively investigated as cancer drug targets. One distinctive feature of PLKs is the presence of a unique polo-box domain (PBD), which regulates kinase activity and subcellular localization. This provides possibilities for specifically targeting PLKs.
Area covered: This article provides an overview of the roles of PLKs in various cancers and related diseases, as well as the drug development involving PLKs, with a particular focus on PLK1 and PLK4. It summarizes the PLK1 and PLK4 inhibitors that have been disclosed in patents or literature (from 2018 - present), which were sourced from SciFinder and WIPO database.
Expert opinion: After two decades of drug development on PLKs, several drugs progressed into clinical trials for the treatment of many cancers; however, none of them has been approved yet. Further elucidating the mechanisms of PLKs and identifying and developing highly selective ATP-competitive inhibitors, highly potent drug-like PBD inhibitors, degraders, etc. may provide new opportunities for cancer therapy and the treatment for several nononcologic diseases. PLKs inhibition-based combination therapies can be another helpful strategy.
Introduction: Cyclin-dependent protein kinase 4/6 (CDK4/6) is a class of serine/threonine protein kinases that plays a key role in the regulation of the cell cycle. CDK4/6 is highly expressed in cancers such as breast cancer, melanoma, and non-small cell lung cancer (NSCLC). Currently, a variety of CDK4/6 inhibitors have been developed, aiming to develop effective inhibitors to solve CDK4/6 resistance and toxicity.
Areas covered: This article searches patents through Espacenet and reviews the development of widely studied CDK inhibitors and FDA-approved CDK4/6 inhibitors, as well as the latest progress of patented inhibitors with good inhibitory activity against CDK4/6 from 2020 to now.
Expert opinion: CDK4/6 is highly expressed in many tumors and has become an important anti-tumor target. Among the patents from 2020 to the present, many inhibitors have good kinase inhibitory effects on CDK4/6 and also show great development potential in anti-tumor. However, there is still an urgent need to develop novel CDK4/6 inhibitors that address challenges such as drug resistance, toxicity, and selectivity.
Introduction: Nearly two decades after leucine rich repeat kinase 2 (LRRK2) was discovered as a genetic determinant of Parkinson's disease (PD), LRRK2 has emerged a priority therapeutic target in PD and inhibition of its activity is hypothesized to be beneficial.
Areas covered: LRRK2 targeting agents, in particular kinase inhibitors and agents reducing LRRK2 expression show promise in model systems and have progressed to phase I and phase II clinical testing for PD. Several additional targeting strategies for LRRK2 are emerging, based on promoting specific 'healthy' LRRK2 quaternary structures, heteromeric complexes and conformations.
Expert opinion: It can be expected that LRRK2 targeting strategies may proceed to phase III clinical testing for PD in the next five years, allowing the field to discover the real clinical value of LRRK2 targeting strategies.
Introduction: Phosphodiesterase 9 (PDE9) has been demonstrated as a potential target for neurological disorders and cardiovascular diseases, such as Alzheimer's disease and heart failure. For the last few years, a series of PDE9 inhibitors with structural diversities have been developed and patented by researchers and pharmaceutical companies, providing insights into first-in-class therapies of PDE9 drug candidates.
Area covered: This review provides an overview of PDE9 inhibitors in patents from 2018 to the present.
Expert opinion: Only a few of the current PDE9 inhibitors are highly selective over other PDEs, which limits their application in pharmacological and clinical research. The design and development of highly selective PDE9 inhibitors remain the top priority in future research. The advantages of targeting PDE9 rather than other PDEs in treating neurodegenerative diseases need to be explained thoroughly. Besides, application of PDE9 inhibitor-based combination therapies sheds light on treating diabetes and refractory heart diseases. Finally, PDE9 inhibitors should be further explored in clinical indications beyond neurological disorders and cardiovascular diseases.