Tivozanib, a highly potent and selective inhibitor of VEGF receptor tyrosine kinases, for the treatment of metastatic renal cell carcinoma

Is Autophagy Targeting a Valid Adjuvant Strategy in Conjunction with Tyrosine Kinase Inhibitors?

Tyrosine kinase inhibitors (TKIs) represent a relatively large class of small-molecule inhibitors that compete with ATP for the catalytic binding site of tyrosine kinase proteins. While TKIs have demonstrated effectiveness in the treatment of multiple malignancies, including chronic myelogenous leukemia, gastrointestinal tumors, non-small cell lung cancers, and HER2-overexpressing breast cancers, as is almost always the case with anti-neoplastic agents, the development of resistance often imposes a limit on drug efficacy. One common survival response utilized by tumor cells to ensure their survival in response to different stressors, including anti-neoplastic drugs, is that of autophagy. The autophagic machinery in response to TKIs in multiple tumor models has largely been shown to be cytoprotective in nature, although there are a number of cases where autophagy has demonstrated a cytotoxic function. In this review, we provide an overview of the literature examining the role that autophagy plays in response to TKIs in different preclinical tumor model systems in an effort to determine whether autophagy suppression or modulation could be an effective adjuvant strategy to increase efficiency and/or overcome resistance to TKIs.

A real-world disproportionality analysis of Tivozanib data mining of the public version of FDA adverse event reporting system

Background

Tivozanib, a vascular endothelial growth factor tyrosine kinase inhibitor, has demonstrated efficacy in a phase III clinical trials for the treatment of renal cell carcinoma. However, comprehensive evaluation of its long-term safety profile in a large sample population remains elusive. The current study assessed Tivozanib-related adverse events of real-world through data mining of the US Food and Drug Administration Adverse Event Reporting System FDA Adverse Event Reporting System.

Methods

Disproportionality analyses, utilizing reporting odds ratio proportional reporting ratio Bayesian confidence propagation neural network and multi-item gamma Poisson shrinker (MGPS) algorithms, were conducted to quantify signals of Tivozanib-related AEs. Weibull distribution was used to predict the varying risk incidence of AEs over time.

Results

Out of 5,361,420 reports collected from the FAERS database, 1,366 reports of Tivozanib-associated AEs were identified. A total of 94 significant disproportionality preferred terms (PTs) conforming to the four algorithms simultaneously were retained. The most common AEs included fatigue, diarrhea, nausea, blood pressure increased, decreased appetite, and dysphonia, consistent with prior specifications and clinical trials. Unexpected significant AEs such as dyspnea, constipation, pain in extremity, stomatitis, and palmar-plantar erythrodysaesthesia syndrome was observed. The median onset time of Tivozanib-related AEs was 37 days (interquartile range [IQR] 11.75-91 days), with a majority (n = 127, 46.35%) occurring within the initial month following Tivozanib initiation.

Conclusion

Our observations align with clinical assertions regarding Tivozanib's safety profile. Additionally, we unveil potential novel and unexpected AE signatures associated with Tivozanib administration, highlighting the imperative for prospective clinical studies to validate these findings and elucidate their causal relationships. These results furnish valuable evidence to steer future clinical inquiries aimed at elucidating the safety profile of Tivozanib.

Recent advances of anti-angiogenic inhibitors targeting VEGF/VEGFR axis

Vascular endothelial growth factors (VEGF), Vascular endothelial growth factor receptors (VEGFR) and their downstream signaling pathways are promising targets in anti-angiogenic therapy. They constitute a crucial system to regulate physiological and pathological angiogenesis. In the last 20 years, many anti-angiogenic drugs have been developed based on VEGF/VEGFR system to treat diverse cancers and retinopathies, and new drugs with improved properties continue to emerge at a fast rate. They consist of different molecular structures and characteristics, which enable them to inhibit the interaction of VEGF/VEGFR, to inhibit the activity of VEGFR tyrosine kinase (TK), or to inhibit VEGFR downstream signaling. In this paper, we reviewed the development of marketed anti-angiogenic drugs involved in the VEGF/VEGFR axis, as well as some important drug candidates in clinical trials. We discuss their mode of action, their clinical benefits, and the current challenges that will need to be addressed by the next-generation of anti-angiogenic drugs. We focus on the molecular structures and characteristics of each drug, including those approved only in China.

Current Status of Tivozanib in the Treatment of Patients With Advanced Renal Cell Carcinoma

The introduction of tyrosine kinase inhibitors (TKIs) against vascular endothelial growth factor receptors (VEGFRs) has transformed the therapeutic landscape for patients with advanced renal cell carcinoma (RCC). However, dose reductions and interruptions are frequently needed due to limited toxicity, mostly from off-target effects. Tivozanib is a potent, selective VEGFR TKI with weak off-target effects. TIVO-1 and TIVO-3 were randomized controlled phase 3 trials that investigated the efficacy and safety of tivozanib versus sorafenib as initial targeted therapy and after failing two previous lines (including targeted therapy), respectively. Tivozanib did not confer any survival advantage, but it significantly increased progression-free survival, response rates, and the duration of responses with a superior safety profile. Although results from subgroup analysis need to be interpreted cautiously, tivozanib demonstrated superiority after two previous lines of VEGFR TKIs or after axitinib, another selective VEGFR inhibitor. Tivozanib also demonstrated durable activity after therapy with an immune-checkpoint inhibitor, while an ongoing study investigating the combination of tivozanib/nivolumab has shown promising preliminary results regarding efficacy and safety. In conclusion, tivozanib was recently added to our therapeutic armamentarium against advanced RCC. Ongoing rational therapeutic combinations of tivozanib will determine the optimal setting in which the maximum benefit can be derived.

To Investigate Growth Factor Receptor Targets and Generate Cancer Targeting Inhibitors

Receptor tyrosine kinase (RTK) regulates multiple pathways, including Mitogenactivated protein kinases (MAPKs), PI3/AKT, JAK/STAT pathway, etc. which has a significant role in the progression and metastasis of tumor. As RTK activation regulates numerous essential bodily processes, including cell proliferation and division, RTK dysregulation has been identified in many types of cancers. Targeting RTK is a significant challenge in cancer due to the abnormal upregulation and downregulation of RTK receptors subfamily EGFR, FGFR, PDGFR, VEGFR, and HGFR in the progression of cancer, which is governed by multiple RTK receptor signalling pathways and impacts treatment response and disease progression. In this review, an extensive focus has been carried out on the normal and abnormal signalling pathways of EGFR, FGFR, PDGFR, VEGFR, and HGFR and their association with cancer initiation and progression. These are explored as potential therapeutic cancer targets and therefore, the inhibitors were evaluated alone and merged with additional therapies in clinical trials aimed at combating global cancer.

Glioblastoma: Current Status, Emerging Targets, and Recent Advances

Glioblastoma (GBM) is a highly malignant brain tumor characterized by a heterogeneous population of genetically unstable and highly infiltrative cells that are resistant to chemotherapy. Although substantial efforts have been invested in the field of anti-GBM drug discovery in the past decade, success has primarily been confined to the preclinical level, and clinical studies have often been hampered due to efficacy-, selectivity-, or physicochemical property-related issues. Thus, expansion of the list of molecular targets coupled with a pragmatic design of new small-molecule inhibitors with central nervous system (CNS)-penetrating ability is required to steer the wheels of anti-GBM drug discovery endeavors. This Perspective presents various aspects of drug discovery (challenges in GBM drug discovery and delivery, therapeutic targets, and agents under clinical investigation). The comprehensively covered sections include the recent medicinal chemistry campaigns embarked upon to validate the potential of numerous enzymes/proteins/receptors as therapeutic targets in GBM.

Oxadiazole: A highly versatile scaffold in drug discovery

As a pharmacologically important heterocycle, oxadiazole paved the way to combat the problem associated with the confluence of many commercially available drugs with different pharmacological profiles. The present review focuses on the potential applications of five-membered heterocyclic oxadiazole derivatives, especially 1,2,4-oxadiazole, 1,2,5-oxadiazole, and 1,3,4-oxadiazole, as therapeutic agents. Designing new hybrid molecules containing the oxadiazole moiety is a better solution for the development of new drug molecules. The designed molecules may accumulate a biological profile better than those of the drugs currently available on the market. The present review will guide the way for researchers in the field of medicinal chemistry to design new biologically active molecules based on the oxadiazole nucleus. Antitubercular, antimalarial, anti-inflammatory, anti-HIV, antibacterial, and anticancer activities of various oxadiazoles have been reviewed extensively here.

Combination Therapy in Renal Cell Carcinoma: the Best Choice for Every Patient?

PURPOSE OF REVIEW

Therapeutic alternatives to treat metastatic renal cell carcinoma (mRCC) are increasing, and combination therapies, including antiangiogenic agents and tyrosine kinase/mTOR/immune checkpoint inhibitors, are identified as the gold standard driven by the results of recent clinical studies. Nevertheless, the real-world RCC population is very heterogeneous, with categories of patients not represented in the enrolled trial population who may not benefit more from these treatments. The purpose of this expert review is to assess the rationale on which tyrosine kinase alone may still be a viable first-line treatment option for some subgroups of patients with mRCC.

RECENT FINDINGS

The first-line treatment with tyrosine kinase inhibitor monotherapy can still be considered an effective tool for addressing selected mRCCs, as highlighted by the successful outcome in a range of subjects such as favorable-risk patients, the ones suffering from autoimmune diseases, those with pancreatic or lung metastases, or previously undergoing organ transplantation and elderly subjects. Some selected categories of patients may still benefit from monotherapy with TKI, and smart sequential therapies can also be considered instead of a combination strategy. Tyrosine kinase inhibitors can also act as immune modulator agents, boosting the immune response to facilitate and potentiate the therapeutic effectiveness of subsequent immunotherapy.

Diarylureas as Antitumor Agents

The diarylurea is a scaffold of great importance in medicinal chemistry as it is present in numerous heterocyclic compounds with antithrombotic, antimalarial, antibacterial, and anti-inflammatory properties. Some diarylureas, serine-threonine kinase or tyrosine kinase inhibitors, were recently reported in literature. The first to come into the market as an anticancer agent was sorafenib, followed by some others. In this review, we survey progress over the past 10 years in the development of new diarylureas as anticancer agents.