Noncardiac vascular toxicities of vascular endothelial growth factor inhibitors in advanced cancer: a review

Innovating Cancer Treatment Through Cell Cycle, Telomerase, Angiogenesis, and Metastasis

Cancer remains a formidable challenge in the field of medicine, necessitating innovative therapeutic strategies to combat its relentless progression. The cell cycle, a tightly regulated process governing cell growth and division, plays a pivotal role in cancer development. Dysregulation of the cell cycle allows cancer cells to proliferate uncontrollably. Therapeutic interventions designed to disrupt the cell cycle offer promise in restraining tumor growth and progression. Telomerase, an enzyme responsible for maintaining telomere length, is often overactive in cancer cells, conferring them with immortality. Targeting telomerase presents an opportunity to limit the replicative potential of cancer cells and hinder tumor growth. Angiogenesis, the formation of new blood vessels, is essential for tumor growth and metastasis. Strategies aimed at inhibiting angiogenesis seek to deprive tumors of their vital blood supply, thereby impeding their progression. Metastasis, the spread of cancer cells from the primary tumor to distant sites, is a major challenge in cancer therapy. Research efforts are focused on understanding the underlying mechanisms of metastasis and developing interventions to disrupt this deadly process. This review provides a glimpse into the multifaceted approach to cancer therapy, addressing critical aspects of cancer biology-cell cycle regulation, telomerase activity, angiogenesis, and metastasis. Through ongoing research and innovative strategies, the field of oncology continues to advance, offering new hope for improved treatment outcomes and enhanced quality of life for cancer patients.

The role of metabolic reprogramming in kidney cancer

Metabolic reprogramming is a cellular process in which cells modify their metabolic patterns to meet energy requirements, promote proliferation, and enhance resistance to external stressors. This process also introduces new functionalities to the cells. The 'Warburg effect' is a well-studied example of metabolic reprogramming observed during tumorigenesis. Recent studies have shown that kidney cells undergo various forms of metabolic reprogramming following injury. Moreover, metabolic reprogramming plays a crucial role in the progression, prognosis, and treatment of kidney cancer. This review offers a comprehensive examination of renal cancer, metabolic reprogramming, and its implications in kidney cancer. It also discusses recent advancements in the diagnosis and treatment of renal cancer.

Toxicities and Quality of Life during Cancer Treatment in Advanced Solid Tumors

The purpose of the study was to identify subgroups of advanced cancer patients who experienced grade 3-4 toxicities as reported by their oncologists as well as identify the demographic, clinical, and treatment symptom characteristics as well as QoL outcomes associated with distinct profiles of each patient. A prospective, multicenter, observational study was conducted with advanced cancer patients of 15 different hospitals across Spain. After three months of systemic cancer treatment, participants completed questionnaires that evaluated psychological distress (BSI-18), quality of life (EORTC QLQ-C30) and fatigue (FAS). The most common tumor sites for the 557 cancer patients with a mean age of 65 years were bronchopulmonary, digestive, and pancreas. Overall, 19% of patients experienced high-grade toxicities (grade 3-4) during treatment. Patients with recurrent advanced cancer, with non-adenocarcinoma cancer, undergoing chemotherapy, and a showing deteriorated baseline status (ECOG > 1) were more likely to experience higher toxicity. Patients who experienced grade 3-4 toxicities during cancer treatment had their treatment suspended in 59% of the cases. Additionally, 87% of the patients had a dose adjustment or a cycle delayed in their treatment due to a high risk of dying during treatment. Future research should focus on identifying interventions to reduce high-grade toxicities and improve quality of life in cancer patients.

Metabolic reprogramming of clear cell renal cell carcinoma

Clear cell renal cell carcinoma (ccRCC) is a malignancy that exhibits metabolic reprogramming as a result of genetic mutations. This reprogramming accommodates the energy and anabolic needs of the cancer cells, leading to changes in glucose, lipid, and bio-oxidative metabolism, and in some cases, the amino acid metabolism. Recent evidence suggests that ccRCC may be classified as a metabolic disease. The metabolic alterations provide potential targets for novel therapeutic interventions or biomarkers for monitoring tumor growth and prognosis. This literature review summarized recent discoveries of metabolic alterations in ccRCC, including changes in glucose, lipid, and amino acid metabolism. The development of metabolic drugs targeting these metabolic pathways was also discussed, such as HIF-2α inhibitors, fatty acid synthase (FAS) inhibitors, glutaminase (GLS) inhibitors, indoleamine 2,3-dioxygenase (IDO) inhibitors, and arginine depletion. Future trends in drug development are proposed, including the use of combination therapies and personalized medicine approaches. In conclusion, this review provides a comprehensive overview of the metabolic alterations in ccRCC and highlights the potential for developing new treatments for this disease.

Comparative Analysis of First-Line FOLFOX Treatment With and Without Anti-VEGF Therapy in Metastatic Colorectal Carcinoma: A Real-World Data Study

BACKGROUND

FOLFOX (leucovorin calcium [folinic acid], fluorouracil, and oxaliplatin) combined with or without anti-VEGF therapy represents one of the primary first-line treatment options for metastatic colorectal carcinoma (mCRC). However, there is limited comparative data on the impact of anti-VEGF therapy on treatment effectiveness, survival outcomes, and tumor location.

METHODS

This retrospective, comparative study utilized data from the AIM Cancer Care Quality Program and commercially insured patients treated at medical oncology clinics in the US. We analyzed 1652 mCRC patients who received FOLFOX, of which 1015 (61.4%) were also treated with anti-VEGF therapy (VEGF cohort).

RESULTS

Patients in the VEGF cohort exhibited a higher frequency of lung (33% vs 23%; P < .001) and liver metastases (74% vs 62%; P < .001), underwent fewer liver surgeries prior to treatment (1.2% vs 3.6%; P = .002), and had a higher proportion of right-sided tumors (27% vs 18%; P = .001). Adjusted analysis revealed no significant difference in overall survival (OS) between patients treated with and without anti-VEGF (median survival: 25.4 vs 26.0 months; P = .4). FOLFOX-only treated patients experienced higher rates of post-treatment hospitalizations (22% vs 15%; P < .001). Notably, left-sided tumors treated with anti-VEGF showed a trend toward decreased OS (median survival: 26.8 vs 33 months; P = .09).

CONCLUSION

Our real-world data analysis suggests that the addition of anti-VEGF to FOLFOX offers limited and short-lived benefits in the context of mCRC and may provide differential survival benefit based on tumor sidedness.

Efficacy and safety of dilpacimab (ABT-165) versus bevacizumab plus FOLFIRI in metastatic colorectal cancer: a phase II study

Aim: This phase II study investigated safety and efficacy of dilpacimab or bevacizumab plus FOLFIRI in patients with previously treated metastatic colorectal cancer (mCRC). Materials & methods: Overall, 66 patients were treated (n = 34 dilpacimab + FOLFIRI; n = 32 bevacizumab + FOLFIRI). Progression-free survival, overall survival, response rates and tolerability were assessed. Results: Median progression-free survival for dilpacimab + FOLFIRI compared with bevacizumab + FOLFIRI was 3.78 months (95% CI: 2.07-7.20) versus 7.36 months (95% CI: 5.68-10.55) (hazard ratio: 3.57; 95% CI: 1.57-8.11; stratified). Median overall survival: 7.95 months for dilpacimab + FOLFIRI; not reached for bevacizumab + FOLFIRI. Objective response rates: 5.6% for dilpacimab + FOLFIRI and 14.7% for bevacizumab + FOLFIRI. Patients treated with dilpacimab + FOLFIRI experienced serious treatment-related adverse events (n = 4; 11.8%), including one case of intestinal perforation leading to death; none were reported for bevacizumab + FOLFIRI. Conclusion: Treatment with dilpacimab + FOLFIRI was not well tolerated and did not provide clinical benefit to patients with mCRC compared with bevacizumab + FOLFIRI. Trial Registration Number: NCT03368859 (Clinicaltrials.gov).

Phase I Open-Label Study Evaluating the Safety, Pharmacokinetics, and Preliminary Efficacy of Dilpacimab in Patients with Advanced Solid Tumors

Dilpacimab (formerly ABT-165), a novel dual-variable domain immunoglobulin, targets both delta-like ligand 4 (DLL4) and VEGF pathways. Here, we present safety, pharmacokinetic (PK), pharmacodynamic (PD), and preliminary efficacy data from a phase I study (trial registration ID: NCT01946074) of dilpacimab in patients with advanced solid tumors. Eligible patients (≥18 years) received dilpacimab intravenously on days 1 and 15 in 28-day cycles at escalating dose levels (range, 1.25-7.5 mg/kg) until progressive disease or unacceptable toxicity. As of August 2018, 55 patients with solid tumors were enrolled in the dilpacimab monotherapy dose-escalation and dose-expansion cohorts. The most common treatment-related adverse events (TRAE) included hypertension (60.0%), headache (30.9%), and fatigue (21.8%). A TRAE of special interest was gastrointestinal perforation, occurring in 2 patients (3.6%; 1 with ovarian and 1 with prostate cancer) and resulting in 1 death. The PK of dilpacimab showed a half-life ranging from 4.9 to 9.5 days, and biomarker analysis demonstrated that the drug bound to both VEGF and DLL4 targets. The recommended phase II dose for dilpacimab monotherapy was established as 3.75 mg/kg, primarily on the basis of tolerability through multiple cycles. A partial response was achieved in 10.9% of patients (including 4 of 16 patients with ovarian cancer). The remaining patients had either stable disease (52.7%), progressive disease (23.6%), or were deemed unevaluable (12.7%). These results demonstrate that dilpacimab monotherapy has an acceptable safety profile, with clinical activity observed in patients with advanced solid tumors.

Results of surgical resection of carotid body tumors: A twenty-year experience

This study examines whether surgical resection of carotid body tumors (CBTs) is acceptable in light of potential significant neurologic complications. This IRB-approved retrospective study analyzed data from 24 patients undergoing surgical treatment for CBTs between April 1998 and April 2017 at Mayo Clinic (Florida campus only). For patients who underwent multiple CBT resections, only data from the first surgery was used in this analysis. CBT resection occurred in 24 patients with the following demographics: fourteen patients (58.3%) were female, median age was 56.5 years, median BMI was 29. A prior history of neoplasm was found in ten patients (41.7%). A known family history of paraganglioma was present in five patients (20.8%). Two patients were positive for succinate dehydrogenase mutation (8.3%). Multiple paragangliomas were present in seven patients (29.2%). There was nerve sacrifice in three patients (12.5%) during resection. Carotid artery reconstruction and patch angioplasty occurred in one patient (4.2%). Complete resection occurred in 24 patients (100.0%). Postoperatively, one patient (4.2%) suffered stroke. No mortalities occurred within or beyond 30 days of surgery. Persistent cranial nerve injury occurred in two patients (8.3%) with vocal cord paralysis. There was no recurrence of CBT through last follow-up. Five patients (20.8%) were diagnosed with other neoplasms after resection, including basal cell carcinoma, contralateral carotid body tumor, glomus vagale, and glomus jugulare. There was 100% survival at 1 year in patients followed for that time (n = 17). Surgical treatment remains the first-line curative treatment to relieve symptoms and ensure non-recurrence. While acceptable, neurologic complications are significant and therefore detailed preoperative informed consent is mandatory.

Potential Successes and Challenges of Targeted Cancer Therapies

The concept and realization of targeted anticancer therapy (TAT) have existed for at least two decades and continue to expand rapidly. It has become clear that there is no "magic bullet" to cure cancer and that even TATs are unlikely to be successful as single agents, necessitating combination with chemotherapy, radiotherapy, or even other targeting agents. The other promise that has not been fulfilled by TAT is that of reduced toxicity. It was thought that by targeting receptors on or within cells, rather than particular phases of the cell cycle, TATs would not be toxic. However, it turns out that the targets also exist on or within normal cells and that there is even cross-reactivity between receptors on nontarget tissues. All of this results in toxicity, the mechanism of which are the same as the mechanism of action of the drugs, making toxicity reduction or prevention very difficult. This leads to new toxicities with new targeted treatments. Nevertheless, all of the above should not detract from the obvious successes of targeted agents, which have turned several acutely fatal cancers into chronic diseases and rendered some hitherto untreatable cancers into treatable diseases.

Cardiogenic shock in cancer

Cardiogenic shock (CS) is increasingly recognized in patients with malignancies, while cancer is independently associated with worse prognosis in CS. A number of conditions may lead to CS in cancer, including acute coronary syndromes, cardiomyopathy, takotsubo syndrome, myocarditis, pulmonary embolism, tamponade, and cardiac herniation. In these conditions, CS may be related to cancer itself or to cancer therapy, including surgery, chemotherapy, or radiotherapy. Given the significantly improved overall survival of patients with malignancies, the early recognition and proper management of CS in cancer become increasingly important. In the present paper, we review the available evidence on CS in patients with malignancies and highlight issues related to its management.

Development of an application for management of drug holidays in perioperative periods

Before surgery and other invasive treatments, decisions must be made on whether to discontinue drugs and provide appropriate drug holidays especially for antithrombotic drugs, and this is made difficult by the large number of available drugs and associated guidelines. We have therefore developed an online application for perioperative drug discontinuation and resumption management, named Saga Application for Management of Drug Holidays in PeriOperative Periods (SAMPOP).Multidisciplinary medical staff at Saga University Hospital (SUH) worked together to build an evidence-based Perioperative Drug Discontinuation Management Database (PDDMD) and developed the user-friendly SAMPOP online application via preliminary verification at SUH. From September 2018 to February 2020, 420 medical staff at SUH, including physicians, nurses, and pharmacists, installed and tested SAMPOP.Rate per surgical procedure for forgetting to discontinue antithrombotic drugs preoperatively decreased from 0.18% to 0.09% as of August 2019, 12 months after the introduction of SAMPOP (P = .1359). In addition, six months later, it decreased further to 0.03% as of February 2020 (P = .0436). Forgetting to resume antithrombotic drugs postoperatively decreased from 0.20% to 0.02% as of August 2019, 12 months after the introduction of SAMPOP (P = .0008). There was no case of forgetting to resume the medication in the last 6 months.SAMPOP may be useful for management of drug holidays in the clinic and warrants further evaluation of its safety and efficacy.

Overview of imaging findings associated with systemic therapies in advanced epithelial ovarian cancer

PURPOSE

To provide an overview for radiologists of the systemic agents used in the treatment of advanced epithelial ovarian cancer (EOC) and their associated toxicities.

RESULTS

EOC is a common gynecological malignancy, with the majority of patients presenting with advanced stage disease at the time of diagnosis. Although primary cytoreductive surgery and chemotherapy are the principal treatments for EOC, recurrence rates of disease remain high. As several molecular targeted therapies have been developed in the last decade, various novel agents have shown efficacy in the treatment of advanced EOC. Advanced EOC will be discussed by outlining the relevant radiological features of toxicities.

CONCLUSION

Knowledge of the systemic therapies utilized in the treatment of advanced EOC and their associated radiological features is critical in diagnostic image interpretation.

Statistical controversies in clinical research: limitations of open-label studies assessing antiangiogenic therapies with regard to evaluation of vascular adverse drug events-a meta-analysis

Background

Previous meta-analyses have shown paradoxical increased risk of bleeding and thrombotic events in patients receiving antiangiogenics (AA) that may be simply explained by the studies design included. By a meta-epidemiological approach, we aim to investigate the impact of double-blind (DB) and open-label study designs on the risks of bleeding, venous thrombotic events (VTE) and arterial thrombotic events (ATE) in cancer patients treated with AA.

Materials and methods

We searched Medline, Cochrane, ClinicalTrials.gov databases and proceedings of major oncology congresses for clinical trials published from January 2003 to January 2016. Randomized clinical trials that assigned patients with solid cancers to AA or control groups were eligible for inclusion. Combined odds ratios (ORs) for the risks of bleeding events, VTE and ATE were calculated for open and DB trials. Estimation bias of the treatment effect was determined by the ratio of OR, by dividing the OR values obtained in open-label trials by those obtained in DB trials.

Results

The literature-based meta-analysis included 166 trials (72 024 patients). For bleeding events, comparison of AA versus control yielded an overall OR of 2.41 [95% confidence interval (95% CI) 2.12-2.73; P < 0.001], but this risk was overestimated by 1.68 (95% CI 1.33-2.13) in open-label studies. Concerning VTE, the OR was 1.19 (95% CI 1.04-1.35; P = 0.012) overall with AA, but this effect disappears when considering only DB trials (OR 0.99, 95% CI 0.83-1.17). The corresponding ratio of OR showed a significant overestimation of 1.53 (95% CI 1.19-1.96) in open-label trials. For ATE, an OR of 1.59 (95% CI 1.30-1.94; P < 0.001) was observed, associated with a significant overestimation of 1.65 (95% CI 1.13-2.43) in open-label trials.

Conclusions

Open-label studies overestimated the risk of vascular adverse events with AA by at least 50%. Meta-analyses assessing adverse drug events should therefore be restricted to DB randomized trials.

Is there truly an increase in risk of cardiovascular and hematological adverse events with vascular endothelial growth factor receptor tyrosine kinase inhibitors?

Objectives: Recent studies have shown an increase risk of cardiovascular and hematological adverse events associated with vascular endothelial growth factor tyrosine kinase inhibitors (VEGF-TKIs). The authors hypothesize that the original studies may have produced exaggerated results because of the small baseline risks involved.Methods: A meta-analysis that included 71 trials, 8 different VEGFR-TKIs, and 11 adverse events were re-analyzed. The outcome of interest was re-defined as the complementary outcome (i.e. remaining free of an adverse event). The inverse variance heterogeneity model was used to pool the effect size.Results: VEGFR-TKIs decreased the risk of remaining free of hypertension by 7% (RR 0.93; 95%CI:0.88-0.97). Specific VEGFR-TKIs; pazopanib, regorafenib, and nintedanib were associated with a decrease risk of remaining free of an arterial thrombotic event (RR 0.96; 95%CI:0.93-0.99), thrombocytopenia (RR 0.91; 95%CI:0.89-0.93), and bleeding (RR 0.96; 95%CI:0.93-0.99) respectively. VEGFR-TKIs were not associated with the thrombotic event, myocardial infarction, stroke, venous thrombotic event, pulmonary embolism, left ventricular dysfunction, or QTc interval prolongation.Conclusion: VEGFR-TKIs are associated with a small increase in the risk of patients developing hypertension, arterial thrombotic events, thrombocytopenia, and bleeding. Previous studies overestimated the actual risk associated with VEGFR-TKIs by analyzing the outcome with the lower baseline risk.

Management of adverse events associated with tyrosine kinase inhibitors: Improving outcomes for patients with hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is the most common form of primary liver cancer. Sorafenib, regorafenib, lenvatinib and cabozantinib are tyrosine kinase inhibitors (TKIs) that target, in part, vascular endothelial growth factor receptors, and are approved in various regions of the world for the treatment of advanced HCC. All these agents are associated with a range of adverse events (AEs) that can have a substantial impact on patients' health-related quality of life. Fatigue, diarrhoea, hand-foot skin reaction, nausea, vomiting, decreased appetite, hypertension and weight loss are among the most common AEs experienced with these four TKIs. In this review, we discuss strategies for the management of these AEs in patients with advanced HCC, with the aim of maximizing treatment benefits and minimizing the need for TKI treatment discontinuation. We also consider potential TKI-drug interactions and discuss the use of TKIs in patients with liver dysfunction or who have experienced tumour recurrence after liver transplantation. Use of appropriate AE management strategies and avoidance of contraindicated drugs should help patients with advanced HCC to achieve optimal outcomes with TKIs.

Ramucirumab: the long and winding road toward being an option for mCRC treatment

INTRODUCTION

Colorectal cancer (CRC) is one of the main causes of cancer-related morbidity and mortality worldwide. Mortality is most often attributable to metastatic disease. Despite the progress achieved so far, life expectancy continues to be limited in most patients. Ramucirumab, a most recent antiangiogenic drug, is vying in the race to metastatic CRC (mCRC) treatment since its approval by the Food and Drug Administration (FDA), based on the results of the RAISE study.

AREAS COVERED

This article reviews the role of ramucirumab in mCRC, including clinical indication, safety issues, and future perspectives.

EXPERT OPINION

The use of Ramucirumab in clinical practice is still limited, probably due to economic burden and the lack of specific biomarkers. Future efforts will be addressed to improve our knowledge in the use of this drug and better guide us in patients' care.

Effects of Antiangiogenetic Drugs on Microcirculation and Macrocirculation in Patients with Advanced-Stage Renal Cancer

Adverse cardiovascular effects, including hypertension, were described in patients with different cancers treated with tyrosine kinase inhibitors (TKI). The mechanism of TKI-related hypertension is still debated. The aim of this work was to study the effects of TKI on blood pressure (BP), searching for a relationship with possible causative factors in patients with metastatic renal cell carcinoma. We included 29 patients in a prospective, observational study; 22 were treated with a first-line drug (sunitinib), while seven participated in the second-line treatment (axitinib or cabozantinib). Patients were investigated at the beginning of antiangiogenic therapy (T0) and at one (T1), three (T2), and six months (T3) after treatment. Patients were evaluated by office blood pressure (BP) and ultrasonography to measure flow-mediated dilatation (FMD), and carotid artery distensibility (cDC) by echocardiography and nailfold capillaroscopy. Plasma endothelin-1 (p-ET-1), urine nitrates, and proteins were also measured. At T1, systolic BP, along with U proteins and p-ET-1, increased significantly. In patients with a clinically significant increase in BP (defined as either the need for an antihypertensive drug or systolic blood pressure (SBP) T1–T0 ≥10 and/or SBP ≥140 mmHg and/or diastolic blood pressure (DBP) T1–T0 ≥5 and/or DBP ≥90 mmHg), the urine nitrate concentration was lower at T0, whereas there were no differences in the p-ET-1 and U proteins. Seventeen participants showed changes in the capillaroscopic pattern at T1 with no association with BP increases. There were no differences in the FMD, cDC, and echocardiographic parameters. Our findings are consistent with those of previous studies about BP increases by TKI, and suggest a role of nitric oxide in BP maintenance in this population.

The Role of Angiogenesis Inhibitors in Hypertension: Following "Ariadne's Thread"

Arterial hypertension (HT) is one of the most frequently recorded comorbidities among patients under antiangiogenic therapy. Inhibitors of vascular endothelial growth factor and vascular endothelial growth factor receptors are most commonly involved in new onset or exacerbation of pre-existing controlled HT. From the pathophysiology point of view, data support that reduced nitric oxide release and sodium and fluid retention, microvascular rarefaction, elevated vasoconstrictor levels, and globular injury might contribute to HT. The purpose of this review was to present recent evidence regarding the incidence of HT induced by antiangiogenic agents, to analyze the pathophysiological mechanisms, and to summarize current recommendations for the management of elevated blood pressure in this field.

VEGFR (Vascular Endothelial Growth Factor Receptor) Inhibition Induces Cardiovascular Damage via Redox-Sensitive Processes

Although VEGF (vascular endothelial growth factor) inhibitors (VEGFIs), are effective anticancer therapies, they cause hypertension through unknown mechanisms. We questioned whether changes in vascular redox state may be important, because VEGF signaling involves nitric oxide (NO) and reactive oxygen species. Molecular mechanisms, including NOS, NADPH oxidase (Nox)–derived reactive oxygen species, antioxidant systems, and vasoconstrictor signaling pathways, were probed in human endothelial cells and vascular smooth muscle exposed to vatalanib, a VEGFI. Vascular functional effects of VEGFI were assessed ex vivo in mouse arteries. Cardiovascular and renal in vivo effects were studied in vatalanib- or gefitinib (EGFI [epidermal growth factor inhibitor])-treated mice. In endothelial cells, vatalanib decreased eNOS (Ser 1177 ) phosphorylation and reduced NO and H 2 O 2 production, responses associated with increased Nox-derived O 2 − and ONOO − formation. Inhibition of Nox1/4 (GKT137831) or Nox1 (NoxA1ds), prevented vatalanib-induced effects. Nrf-2 (nuclear factor erythroid 2–related factor 2) nuclear translocation and expression of Nrf-2–regulated antioxidant enzymes were variably downregulated by vatalanib. In human vascular smooth muscles, VEGFI increased Nox activity and stimulated Ca 2+ influx and MLC 20 phosphorylation. Acetylcholine-induced vasodilatation was impaired and U46619-induced vasoconstriction was enhanced by vatalanib, effects normalized by N-acetyl-cysteine and worsened by L-NAME. In vatalanib-, but not gefitinib-treated mice vasorelaxation was reduced and media:lumen ratio of mesenteric arteries was increased with associated increased cardiovascular and renal oxidative stress, decreased Nrf-2 activity and downregulation of antioxidant genes. We demonstrate that inhibition of VEGF signaling induces vascular dysfunction through redox-sensitive processes. Our findings identify Noxs and antioxidant enzymes as novel targets underling VEGFI-induced vascular dysfunction. These molecular processes may contribute to vascular toxicity and hypertension in VEGFI-treated patients.

The Discovery of N-(1-Methyl-5-(trifluoromethyl)-1H-pyrazol-3-yl)-5-((6- ((methylamino)methyl)pyrimidin-4-yl)oxy)-1H-indole-1-carboxamide (Acrizanib), a VEGFR-2 Inhibitor Specifically Designed for Topical Ocular Delivery, as a Therapy for Neovascular Age-Related Macular Degeneration

A noninvasive topical ocular therapy for the treatment of neovascular or "wet" age-related macular degeneration would provide a patient administered alternative to the current standard of care, which requires physician administered intravitreal injections. This manuscript describes a novel strategy for the use of in vivo models of choroidal neovascularization (CNV) as the primary means of developing SAR related to efficacy from topical administration. Ultimately, this effort led to the discovery of acrizanib (LHA510), a small-molecule VEGFR-2 inhibitor with potency and efficacy in rodent CNV models, limited systemic exposure after topical ocular administration, multiple formulation options, and an acceptable rabbit ocular PK profile.

Efficacy and safety of targeting VEGFR drugs in treatment for advanced or metastatic gastric cancer: a systemic review and meta-analysis

The value of targeting VEGFR (vascular endothelial growth factor receptor) drugs has demonstrated encouraging anti-cancer activity in advanced solid tumors within current clinical trials. This study aimed to serve as the first systemic review to assess their safety and efficacy according to biochemical characteristics of targeting VEGFR drugs in gastric cancer. We analyzed eight clinical trials on targeting VEGFR drugs in gastric cancer. Results showed that targeting VEGFR drugs significantly improved overall survival (OS) [Hazard Ratio (HR) 0.69, 95% confidence interval (CI) (0.55, 0.83), P < 0.001], progression free survival (PFS) [HR 0.50, 95% CI (0.34, 0.66), P < 0.001], disease control rate (DCR) [Odds Ratio (OR) 3.83, 95% CI (2.39, 6.15), P < 0.001] and significantly decreased the progressive disease rate(PDR)[OR 0.45, 95% CI (0.34, 0.59), P < 0.001], but not objective response rate (ORR) [OR 1.46, 95% CI (0.93, 2.29), P = 0.098]. Further subgroup revealed that VEGFR antibody (VEGFR-Ab) drugs were superior to VEGFR tyrosine kinase inhibitor (VEGFR-TKI) drugs in terms of the OS, PFS and PDR. To determine the toxic effect of targeting VEGFR drugs, the relative risk of adverse events (grade ≥ 3) of special interest(AESIs) were estimated. Most of these were predictable and manageable. Furthermore, less AESIs were observed in the VEGFR-Ab than the VEGFR-TKI drugs. In conclusion, VEGFR drugs were effective targeted therapy in advanced or metastatic gastric cancer, and its toxicity is within a controllable range. VEGFR-Ab drugs were more effective than VEGFR-TKI drugs in terms of the OS, PFS and PDR of gastric cancer patients with little toxicity.

Quantifying the relationship between inhibition of VEGF receptor 2, drug-induced blood pressure elevation and hypertension

BACKGROUND AND PURPOSE

Several anti-angiogenic cancer drugs that inhibit VEGF receptor (VEGFR) signalling for efficacy are associated with a 15-60% incidence of hypertension. Tyrosine kinase inhibitors (TKIs) that have off-target activity at VEGFR-2 may also cause blood pressure elevation as an undesirable side effect. Therefore, the ability to translate VEGFR-2 off-target potency into blood pressure elevation would be useful in development of novel TKIs. Here, we have sought to quantify the relationship between VEGFR-2 inhibition and blood pressure elevation for a range of kinase inhibitors.

EXPERIMENTAL APPROACH

Porcine aortic endothelial cells overexpressing VEGFR-2 (PAE) were used to determine IC₅₀ for VEGFR-2 phosphorylation. These IC₅₀ values were compared with published reports of exposure attained during clinical use and the corresponding incidence of all-grade hypertension. Unbound average plasma concentration (C_av,u ) was selected to be the most appropriate pharmacokinetic parameter. The pharmacokinetic-pharmacodynamic (PKPD) relationship for blood pressure elevation was investigated for selected kinase inhibitors, using data derived either from clinical papers or from rat telemetry experiments.

KEY RESULTS

All-grade hypertension was predominantly observed when the C_av,u was >0.1-fold of the VEGFR-2 (PAE) IC₅₀ . Furthermore, based on the PKPD analysis, an exposure-dependent blood pressure elevation >1 mmHg was observed only when the C_av,u was >0.1-fold of the VEGFR-2 (PAE) IC₅₀ .

CONCLUSIONS AND IMPLICATIONS

Taken together, these data show that the risk of blood pressure elevation is proportional to the amount of VEGFR-2 inhibition, and a margin of >10-fold between VEGFR-2 IC₅₀ and C_av,u appears to confer a minimal risk of hypertension.

Risk of gastrointestinal events with newly approved (after 2011) vascular endothelial growth factor receptor tyrosine kinase inhibitors in cancer patients: a meta-analysis of randomized controlled trials

PURPOSE

We performed a meta-analysis to systematically review the gastrointestinal (GI) events (diarrhea, nausea, vomiting, anorexia) of five newly approved (after 2011) VEGFR-TKIs in cancer patients.

METHODS

The relevant studies of the randomized controlled trials (RCTs) in cancer patients treated with cabozantinib, vandetanib, lenvatinib, regorafenib, and axitinib were retrieved and the systematic evaluation was conducted.

RESULTS

Forty-one randomized controlled trials and 10,860 patients were included. Current analysis suggested that the use of these agents increased the risk of all-grade and high-grade GI events, and the diarrhea was the most common GI events. The risk of all-grade and high-grade GI events varies significantly within drug types, tumor types, and VEGFR-TKIs-based regimens.

CONCLUSION

The available data suggested that the use of the five newly approved VEGFR-TKIs may increase risk of GI events in cancer patients. Physicians and patients should be aware of these risks and frequent monitoring and careful management should be emphasized when managing these VEGFR-TKIs.

The value of [11C]-acetate PET and [18F]-FDG PET in hepatocellular carcinoma before and after treatment with transarterial chemoembolization and bevacizumab

Purpose

This prospective study was to investigate the value of [¹¹C]-acetate PET and [¹⁸F]-FDG PET in the evaluation of hepatocellular carcinoma (HCC) before and after treatment with transarterial chemoembolization (TACE) and vascular endothelial growth factor (VEGF) antibody (bevacizumab).

Methods

Twenty-two patients (three women, 19 men; 62 ± 8 years) with HCC verified by histopathology were treated with TACE and bevacizumab (n = 11) or placebo (n = 11). [¹¹C]-acetate PET and [¹⁸F]-FDG PET were performed before and after TACE with bevacizumab or placebo. Comparisons between groups were performed with t-tests and Chi-squared tests, where appropriate. Overall survival (OS) was defined as the time from start of bevacizumab or placebo until the date of death/last follow-up, respectively.

Results

The patient-related sensitivity of [¹¹C]-acetate PET, [¹⁸F]-FDG PET, and combined [¹¹C]-acetate and [¹⁸F]-FDG PET was 68%, 45%, and 73%, respectively. There was a significantly higher rate of conversion from [¹¹C]-acetate positive lesions to negative lesions in patients treated with TACE and bevacizumab as compared with that in patients with TACE and placebo (p < 0.05). In patients with negative acetate PET, the mean OS in patients treated with TACE and bevacizumab was 259 ± 118 days and was markedly shorter as compared with that (668 ± 217 days) in patients treated with TACE and placebo (p < 0.05). In patients treated with TACE and placebo, there was significant difference in mean OS in patients with positive FDG PET as compared with that in patients with negative FDG PET (p < 0.05). The HCC lesions had different tracer avidities showing the heterogeneity of HCC.

Conclusions

Our study suggests that combining [¹⁸F]-FDG with [¹¹C]-acetate PET could be useful for the management of HCC patients and might also provide relevant prognostic and molecular heterogeneity information.

Vascular Complications of Cancer Chemotherapy

Development of new anticancer drugs has resulted in improved mortality rates and 5-year survival rates in patients with cancer. However, many of the modern chemotherapies are associated with cardiovascular toxicities that increase cardiovascular risk in cancer patients, including hypertension, thrombosis, heart failure, cardiomyopathy, and arrhythmias. These limitations restrict treatment options and might negatively affect the management of cancer. The cardiotoxic effects of older chemotherapeutic drugs such as alkylating agents, antimetabolites, and anticancer antibiotics have been known for a while. The newer agents, such as the antiangiogenic drugs that inhibit vascular endothelial growth factor signalling are also associated with cardiovascular pathology, especially hypertension, thromboembolism, myocardial infarction, and proteinuria. Exact mechanisms by which vascular endothelial growth factor inhibitors cause these complications are unclear but impaired endothelial function, vascular and renal damage, oxidative stress, and thrombosis might be important. With increasing use of modern chemotherapies and prolonged survival of cancer patients, the incidence of cardiovascular disease in this patient population will continue to increase. Accordingly, careful assessment and management of cardiovascular risk factors in cancer patients by oncologists and cardiologists working together is essential for optimal care so that prolonged cancer survival is not at the expense of increased cardiovascular events.

Discovery of Oral VEGFR-2 Inhibitors with Prolonged Ocular Retention That Are Efficacious in Models of Wet Age-Related Macular Degeneration

The benefit of intravitreal anti-VEGF therapy in treating wet age-related macular degeneration (AMD) is well established. Identification of VEGFR-2 inhibitors with optimal ADME properties for an ocular indication provides opportunities for dosing routes beyond intravitreal injection. We employed a high-throughput in vivo screening strategy with rodent models of choroidal neovascularization and iterative compound design to identify VEGFR-2 inhibitors with potential to benefit wet AMD patients. These compounds demonstrate preferential ocular tissue distribution and efficacy after oral administration while minimizing systemic exposure.

Toward a Cancer Drug of Fungal Origin

Although fungi produce highly structurally diverse metabolites, many of which have served as excellent sources of pharmaceuticals, no fungi-derived agent has been approved as a cancer drug so far. This is despite a tremendous amount of research being aimed at the identification of fungal metabolites with promising anticancer activities. This review discusses the results of clinical testing of fungal metabolites and their synthetic derivatives, with the goal to evaluate how far we are from an approved cancer drug of fungal origin. Also, because in vivo studies in animal models are predictive of the efficacy and toxicity of a given compound in a clinical situation, literature describing animal cancer testing of compounds of fungal origin is reviewed as well. Agents showing the potential to advance to clinical trials are also identified. Finally, the technological challenges involved in the exploitation of fungal biodiversity and procurement of sufficient quantities of clinical candidates are discussed, and potential solutions that could be pursued by researchers are highlighted.

Anti-angiogenic-specific adverse events in patients with non-small cell lung cancer treated with nintedanib and docetaxel

OBJECTIVES

LUME-Lung 1 was a randomized, placebo-controlled, Phase III trial investigating nintedanib+docetaxel versus placebo+docetaxel in patients with advanced NSCLC progressing after first-line chemotherapy. Progression-free survival was significantly improved with nintedanib+docetaxel in the overall population and overall survival was significantly improved in the pre-specified analysis of patients with adenocarcinoma. We evaluated the frequency of characteristic adverse events (AEs) commonly seen with existing anti-angiogenic agents.

MATERIALS AND METHODS

The incidence and intensity of AEs were evaluated in all patients who received at least one dose of study medication (N=1307) and for the two main histologies: adenocarcinoma (n=653) and squamous cell carcinoma (SCC; n=553). AEs of special interest were analyzed by category, preferred term, and worst CTCAE grade and included perforation, hypertension, bleeding, thromboembolic events, and skin disorders.

RESULTS AND CONCLUSION

The incidence of patients with all-grade gastrointestinal (GI) perforations was low and balanced between arms (0.5% in both) and across histologies; the incidence of non-GI perforations was 1.2% with nintedanib+docetaxel versus 0.2% with placebo+docetaxel. The incidence of some events was higher with nintedanib+docetaxel versus placebo+docetaxel; hypertension (3.5% vs 0.9%), rash (11.0% vs 8.1%), and cutaneous adverse reactions (13.0% vs 10.7%). Rash and cutaneous adverse reactions were predominantly Grade 1-2 with both treatments. The incidence of all-grade bleeding was also slightly higher in nintedanib+docetaxel-treated patients (14.1% vs 11.6%) driven by between-treatment differences in the SCC subpopulation; most events were Grade 1-2. The proportion of patients with a thromboembolic event was low and comparable between arms for all grades (5.1% vs 4.6%) and Grade ≥3 (2.1% vs 3.1%). Safety evaluation of the LUME-Lung 1 study showed that the frequency of AEs commonly associated with other anti-angiogenic agents was lower with nintedanib+docetaxel. Survival benefits from addition of nintedanib to docetaxel in patients with adenocarcinoma after first-line therapy can be achieved alongside a manageable safety profile.

Hepatocellular Carcinoma: A Phase II Randomized Controlled Double-Blind Trial of Transarterial Chemoembolization in Combination with Biweekly Intravenous Administration of Bevacizumab or a Placebo

PURPOSE

To investigate the efficacy and safety of conventional transarterial chemoembolization (TACE) (cTACE) in combination with bevacizumab or a placebo in patients with hepatocellular carcinoma (HCC) in a randomized controlled double-blind phase II trial.

MATERIALS AND METHODS

This study was approved by the institutional review board, and written informed consent was obtained prior to inclusion. A total of 40 patients (20 patients per group, all 18 years or older) with histologically confirmed early- or intermediate-stage HCC and Child-Pugh class A or B cirrhosis were scheduled for inclusion. The primary endpoint was radiologic progression at 12 months according to European Association for the Study of the Liver criteria. Secondary endpoints were safety and overall survival (OS). Patients underwent cTACE with doxorubicin and intravenous administration of a placebo (cTACE-C) or bevacizumab (cTACE-B) (5 mg per kilogram of body weight) every 2 weeks for 52 weeks. After the first TACE procedure, TACE was repeated twice in 4-week intervals if indicated and technically feasible and on demand thereafter. Statistical analyses were performed with statistical software. P < .05 indicated a significant difference.

RESULTS

Thirty-two patients were recruited between January 2006 and December 2009 (29 male, three female; mean age, 61 years ± 8 [standard deviation]; Barcelona Clinic Liver Cancer stage A, n = 4; Barcelona Clinic Liver Cancer stage B, n = 28; predominant cause, alcohol [n = 15]; Child-Pugh class A disease, n = 22; Child-Pugh class B disease, n = 10; 16 patients received bevacizumab; 16 patients received a placebo). Patients underwent a median of three TACE cycles and received 13 infusions of bevacizumab versus 11 infusions of the placebo before the trial was stopped prematurely for safety reasons. Severe (grade 3-5) septic (n = 8 vs n = 3) and vascular (n = 9 vs n = 0) side effects were observed almost exclusively in the cTACE-B group. Median survival was worse in the cTACE-B group than in the cTACE-C group (5.3 vs 13.7 months; hazard ratio [HR], 1.7; 95% confidence interval [CI]: 0.8, 3.6; P = .195) and reached significance in patients with Child-Pugh class A cirrhosis (7.3 vs 26.5 months; HR, 2.6; 95% CI: 1.0, 6.6; P = .049). The primary endpoint was not met, since there was no difference in radiologic response between the groups at 3, 6, or 12 months.

CONCLUSION

No improvement in radiologic tumor response or OS was observed in patients with HCC who received cTACE and bevacizumab, but severe and even lethal septic and vascular side effects occurred. Thus, bevacizumab cannot be recommended as an adjuvant treatment to cTACE.

Therapeutic manipulation of angiogenesis with miR-27b

BACKGROUND

Multiple studies demonstrated pro-angiogenic effects of microRNA (miR)-27b. Its targets include Notch ligand Dll4, Sprouty (Spry)-2, PPARγ and Semaphorin (SEMA) 6A. miR-27 effects in the heart are context-dependent: although it is necessary for ventricular maturation, targeted overexpression in cardiomyocytes causes hypertrophy and dysfunction during development. Despite significant recent advances, therapeutic potential of miR-27b in cardiovascular disease and its effects in adult heart remain unexplored. Here, we assessed the therapeutic potential of miR-27b mimics and inhibitors in rodent models of ischemic disease and cancer.

METHODS

We have used a number of models to demonstrate the effects of miR-27b mimicry and inhibition in vivo, including subcutaneous Matrigel plug assay, mouse models of hind limb ischemia and myocardial infarction and subcutaneous Lewis Lung carcinoma.

RESULTS

Using mouse model of myocardial infarction due to the coronary artery ligation, we showed that miR-27b mimic had overall beneficial effects, including increased vascularization, decreased fibrosis and increased ejection fraction. In mouse model of critical limb ischemia, miR-27b mimic also improved tissue re-vascularization and perfusion. In both models, miR-27b mimic clearly decreased macrophage recruitment to the site of hypoxic injury. In contrast, miR-27b increased the recruitment of bone marrow derived cells to the neovasculature, as was shown using mice reconstituted with fluorescence-tagged bone marrow. These effects were due, at least in part, to the decreased expression of Dll4, PPARγ and IL10. In contrast, blocking miR-27b significantly decreased vascularization and reduced growth of subcutaneous tumors and decreased BMDCs recruitment to the tumor vasculature.

CONCLUSIONS

Our study demonstrates the utility of manipulating miR-27b levels in the treatment of cardiovascular disease and cancer.

The adverse effects of sorafenib in patients with advanced cancers

Sorafenib is the first multi-kinase inhibitor (TKI) approved for the treatment of advanced hepatocellular cancer (HCC) and metastatic renal cell cancer (RCC) and is increasingly being used to treat patients with well-differentiated radioiodine-resistant thyroid cancer (DTC). Sorafenib demonstrates targeted activity on several families of receptor and non-receptor tyrosine kinases that are involved in angiogenesis, tumour growth and metastatic progression of cancer. Sorafenib treatment results in long-term efficacy and low incidence of life-threatening toxicities. Although sorafenib has demonstrated many benefits in patients, the adverse effects cannot be ignored. The most common treatment-related toxicities include diarrhoea, fatigue, hand-foot skin reaction and hypertension. Most of these toxicities are considered mild to moderate and manageable to varying degrees; however, cardiovascular events might lead to death. In this MiniReview, we summarize the adverse effects of sorafenib that commonly occur in patients with advanced cancers.

The contribution of VEGF signalling to fostamatinib-induced blood pressure elevation

BACKGROUND AND PURPOSE

Fostamatinib is an inhibitor of spleen tyrosine kinase (TK). In patients, fostamatinib treatment was associated with increased BP. Some TK inhibitors cause BP elevation, by inhibiting the VEGF receptor 2 (VEGFR2). Here, we have assessed the mechanistic link between fostamatinib-induced BP elevation and inhibition of VEGF signalling.

EXPERIMENTAL APPROACH

We used conscious rats with automated blood sampling and radio telemetry and anaesthetized rats to measure cardiovascular changes. Rat isolated aorta and isolated hearts, and human resistance vessels in vitro were also used. NO production by human microvascular endothelial cells was measured with the NO-dependent probe, DAF-FM and VEGFR2 phosphorylation was determined in mouse lung, ex vivo.

KEY RESULTS

In conscious rats, fostamatinib dose-dependently increased BP. The time course of the BP effect correlated closely with the plasma concentrations of R406 (the active metabolite of fostamatinib). In anaesthetized rats, infusion of R406 increased BP and decreased femoral arterial conductance. Endothelial function was unaffected, as infusion of R406 did not inhibit hyperaemia- or ACh-induced vasodilatation in rats. R406 did not affect contraction of isolated blood vessels. R406 inhibited VEGF-stimulated NO production from human endothelial cells in vitro, and treatment with R406 inhibited VEGFR2 phosphorylation in vivo. R406 inhibited VEGF-induced hypotension in anaesthetized rats.

CONCLUSIONS AND IMPLICATIONS

Increased vascular resistance, secondary to reduced VEGF-induced NO release from endothelium, may contribute to BP increases observed with fostamatanib. This is consistent with the elevated BP induced by other drugs inhibiting VEGF signalling, although the contribution of other mechanisms cannot be excluded.

Systematic review of the risk of adverse outcomes associated with vascular endothelial growth factor inhibitors for the treatment of cancer

BACKGROUND

Anti-angiogenic therapy targeted at vascular endothelial growth factor (VEGF) is now used to treat several types of cancer. We did a systematic review of randomized controlled trials (RCTs) to summarize the adverse effects of vascular endothelial growth factor inhibitors (VEGFi), focusing on those with vascular pathogenesis.

METHODS AND FINDINGS

We searched MEDLINE, EMBASE and Cochrane Library until April 19, 2012 to identify parallel RCTs comparing a VEGFi with a control among adults with any cancer. We pooled the risk of mortality, vascular events (myocardial infarction, stroke, heart failure, and thromboembolism), hypertension and new proteinuria using random-effects models and calculated unadjusted relative risk (RR). We also did meta-regression and assessed publication bias. We retrieved 83 comparisons from 72 studies (n = 38,078) on 11 different VEGFi from 7901 identified citations. The risk of mortality was significantly lower among VEGFi recipients than controls (pooled RR 0.96, 95% confidence interval [CI] 0.94 to 0.98, I2 = 0%, tau2 = 0; risk difference 2%). Compared to controls, VEGFi recipients had significantly higher risk of myocardial infarction (MI) (RR 3.54, 95% CI 1.61 to 7.80, I2 = 0%, tau2 = 0), arterial thrombotic events (RR 1.80, 95% CI 1.24 to 2.59, I2 = 0%, tau2 = 0); hypertension (RR 3.46, 95% CI 2.89 to 4.15, I2 = 58%, tau2 = 0.16), and new proteinuria (RR 2.51, 95% CI 1.60 to 3.94, I2 = 87%, tau2 = 0.65). The absolute risk difference was 0.8% for MI, 1% for arterial thrombotic events, 15% for hypertension and 12% for new proteinuria. Meta-regression did not suggest any statistically significant modifiers of the association between VEGFi treatment and any of the vascular events. Limitations include heterogeneity across the trials.

CONCLUSIONS

VEGFi increases the risk of MI, hypertension, arterial thromboembolism and proteinuria. The absolute magnitude of the excess risk appears clinically relevant, as the number needed to harm ranges from 7 to 125. These adverse events must be weighed against the lower mortality associated with VEGFi treatment.

Nonclinical Safety Biomarkers of Drug-induced Vascular Injury

Better biomarkers are needed to identify, characterize, and/or monitor drug-induced vascular injury (DIVI) in nonclinical species and patients. The Predictive Safety Testing Consortium (PSTC), a precompetitive collaboration of pharmaceutical companies and the U.S. Food and Drug Administration (FDA), formed the Vascular Injury Working Group (VIWG) to develop and qualify translatable biomarkers of DIVI. The VIWG focused its research on acute DIVI because early detection for clinical and nonclinical safety monitoring is desirable. The VIWG developed a strategy based on the premise that biomarkers of DIVI in rat would be translatable to humans due to the morphologic similarity of vascular injury between species regardless of mechanism. The histomorphologic lexicon for DIVI in rat defines degenerative and adaptive findings of the vascular endothelium and smooth muscles, and characterizes inflammatory components. We describe the mechanisms of these changes and their associations with candidate biomarkers for which advanced analytical method validation was completed. Further development is recommended for circulating microRNAs, endothelial microparticles, and imaging techniques. Recommendations for sample collection and processing, analytical methods, and confirmation of target localization using immunohistochemistry and in situ hybridization are described. The methods described are anticipated to aid in the identification and qualification of translational biomarkers for DIVI.

Do anti-angiogenic cancer therapies increase risk of significant weight loss?

INTRODUCTION

Angiogenesis is important in many disease states such as cancer. Anti-angiogenic cancer drugs are in broad use for the treatment of cancers. However, currently most of these anticancer drugs result in some adverse effects in the patient.

AREAS COVERED

In this paper, we review evidence on the association between anti-angiogenic therapies and weight loss. We report on basic experiments and clinical trials that measure weight loss with anti-angiogenic cancer therapies.

EXPERT OPINION

Few strong associations are found between anti-angiogenic cancer therapies and weight loss, with the exception of some multikinase inhibitors in clinical trials. Anti-angiogenic cancer therapies appear safe in relation to weight loss, but the result needs to be established by further clinical trials.

Hypertension due to antiangiogenic cancer therapy with vascular endothelial growth factor inhibitors: understanding and managing a new syndrome

Novel antiangiogenic cancer therapies, particularly agents that block vascular endothelial growth factor (VEGF) signalling, have improved outcomes in patients with cancers and are now used as first-line therapies for some tumours. However, with VEGF inhibitors (VEGFIs) are new complications, particularly hypertension. VEGFI-induced hypertension is a dose-dependent phenomenon due to on-target effects rather than off-target effects. Increased blood pressure occurs in almost 100% of patients who take VEGFIs, with a subset who develop severe hypertension. Molecular mechanisms underlying VEGFI-induced hypertension are unclear, but endothelial dysfunction and increased vascular resistance, due to impaired nitric oxide signalling, reduced prostacyclin production, endothelin-1 (ET-1) upregulation, oxidative stress, and rarefaction have been implicated. Treatment of hypertension should be aimed at reducing the risk of short-term morbidity associated with hypertension while maintaining effective dosing of antiangiogenic therapy for optimal cancer treatment. Although specific guidelines are not yet available for the management of VEGFI-induced hypertension, angiotensin-converting enzyme inhibitors and dihydropyridine calcium channel blockers are commonly used. Severe hypertension might require reduction of VEGFI dosing, or in some cases, interruption of treatment. As more potent VEGFIs are developed and as more cancer patients are treated with VEGFIs, the burden of hypertension toxicity will increase. This will be further compounded as the use of antiangiogenic drugs broadens to include older patients and those with pre-existing cardiovascular disease. Here we focus on VEGF as a target for antiangiogenesis and how this affects increased blood pressure. Putative mechanisms underlying VEGFI-induced hypertension are highlighted and therapeutic strategies to manage such hypertension are discussed.

Consumptive coagulopathy in angiosarcoma: a recurrent phenomenon?

Objectives. To report the prevalence of consumptive coagulopathy in angiosarcoma patients seen at a single center. Methods. We retrospectively reviewed case records of 42 patients diagnosed with angiosarcoma at Mount Sinai Hospital between 2000 and 2013. Results. Seven patients (17%) met clinical criteria for disseminated intravascular coagulation (DIC) in absence of concomitant clinical states known to cause coagulopathy or myelosuppression. In all patients who received systemic antineoplastic therapy with resultant disease response or stability, DIC resolved in tandem with clinical improvement. DIC recurred at time of disease progression in all cases. Two patients had bulky disease, defined as diameter of largest single or contiguous tumor mass measuring 5 cm or more. All patients demonstrated an aggressive clinical course with short duration of disease control and demise within 1 year. In contrast, evaluation over the same period of 17 epithelioid hemangioendothelioma patients serving as a clinical control group revealed no evidence of DIC. Conclusion. Angiosarcomas can be associated with a consumptive coagulopathy arising in tandem with disease activity. Vigilance for this complication will be needed in the course of often aggressive multimodality therapy. The potential utility of coagulopathy as a prognostic biomarker will need to be explored in future studies.

Safety, pharmacokinetics, pharmacodynamics, and antitumor activity of dalantercept, an activin receptor-like kinase-1 ligand trap, in patients with advanced cancer

PURPOSE

The angiogenesis inhibitor dalantercept (formerly ACE-041) is a soluble form of activin receptor-like kinase-1 (ALK1) that prevents activation of endogenous ALK1 by bone morphogenetic protein-9 (BMP9) and BMP10 and exhibits antitumor activity in preclinical models. This first-in-human study of dalantercept evaluated its safety, tolerability, pharmacokinetics, pharmacodynamics, and antitumor activity in adults with advanced solid tumors.

EXPERIMENTAL DESIGN

Patients in dose-escalating cohorts received dalantercept subcutaneously at one of seven dose levels (0.1-4.8 mg/kg) every 3 weeks until disease progression. Patients in an expansion cohort received dalantercept at 0.8 or 1.6 mg/kg every 3 weeks until disease progression.

RESULTS

In 37 patients receiving dalantercept, the most common treatment-related adverse events were peripheral edema, fatigue, and anemia. Edema and fluid retention were dose-limiting toxicities and responded to diuretic therapy. No clinically significant, treatment-related hypertension, proteinuria, gross hemorrhage, or gastrointestinal perforations were observed. One patient with refractory squamous cell cancer of the head and neck had a partial response, and 13 patients had stable disease according to RECISTv1.1, eight of whom had prolonged periods (≥12 weeks) of stable disease. Correlative pharmacodynamic markers included tumor metabolic activity and tumor blood flow, which decreased from baseline in 63% and 82% of evaluable patients, respectively, and telangiectasia in eight patients.

CONCLUSION

Dalantercept was well-tolerated at doses up to 1.6 mg/kg, with a safety profile distinct from inhibitors of the VEGF pathway. Dalantercept displayed promising antitumor activity in patients with advanced refractory cancer, and multiple phase II studies are underway.

Tyrosine kinase inhibitors: their on-target toxicities as potential indicators of efficacy

Tyrosine kinase inhibitors (TKIs) have revolutionized the treatment of certain forms of cancers, raising hopes for many patients with otherwise unresponsive tumours. While these agents are generally well tolerated, clinical experience with them has highlighted their unexpected association with serious toxic effects on various organs such as the heart, lungs, liver, kidneys, thyroid, skin, blood coagulation, gastrointestinal tract and nervous system. Many of these toxic effects result from downstream inhibition of vascular endothelial growth factor or epidermal growth factor signalling in cells of normal organs. Many of these undesirable effects such as hypertension, hypothyroidism, skin reactions and possibly proteinuria are on-target effects. Since tyrosine kinases are widely distributed with specific functional roles in different organs, this association is not too surprising. Various studies suggest that the development of these on-target effects indicates clinically desirable and effective inhibition of the corresponding ligand-mediated receptor linked with oncogenesis. This is reflected as improved efficacy in the subgroup of patients who develop these on-target adverse effects compared with those who do not. Inevitably, issues arise with respect to the regulatory assessment of efficacy and risk/benefit of the TKIs as well as the clinical approach to managing patients who develop these effects. Routine subgroup analysis of efficacy data from clinical trials (patients with and without on-target toxicity) may enable more effective clinical use of TKIs since (i) discontinuing or reducing the dose of the TKI has a negative impact if the tumour is TKI-responsive; and (ii) it is usually possible to manage these undesirable on-target effects with conventional clinical approaches. Prospective studies are needed to investigate this proposition further.