Xerna™ TME Panel is a machine learning-based transcriptomic biomarker designed to predict therapeutic response in multiple cancers.

Introduction: Most predictive biomarkers approved for clinical use measure single analytes such as genetic alteration or protein overexpression. We developed and validated a novel biomarker with the aim of achieving broad clinical utility. The Xerna™ TME Panel is a pan-tumor, RNA expression-based classifier, designed to predict response to multiple tumor microenvironment (TME)-targeted therapies, including immunotherapies and anti-angiogenic agents. Methods: The Panel algorithm is an artificial neural network (ANN) trained with an input signature of 124 genes that was optimized across various solid tumors. From the 298-patient training data, the model learned to discriminate four TME subtypes: Angiogenic (A), Immune Active (IA), Immune Desert (ID), and Immune Suppressed (IS). The final classifier was evaluated in four independent clinical cohorts to test whether TME subtype could predict response to anti-angiogenic agents and immunotherapies across gastric, ovarian, and melanoma datasets. Results: The TME subtypes represent stromal phenotypes defined by angiogenesis and immune biological axes. The model yields clear boundaries between biomarker-positive and -negative and showed 1.6-to-7-fold enrichment of clinical benefit for multiple therapeutic hypotheses. The Panel performed better across all criteria compared to a null model for gastric and ovarian anti-angiogenic datasets. It also outperformed PD-L1 combined positive score (>1) in accuracy, specificity, and positive predictive value (PPV), and microsatellite-instability high (MSI-H) in sensitivity and negative predictive value (NPV) for the gastric immunotherapy cohort. Discussion: The TME Panel's strong performance on diverse datasets suggests it may be amenable for use as a clinical diagnostic for varied cancer types and therapeutic modalities.

Intracranial efficacy and safety of furmonertinib 160 mg with or without anti-angiogenic agent in advanced NSCLC patients with BM/LM as salvage therapy.

OBJECTIVES: Central nervous system (CNS) metastases including brain metastases (BM) and leptomeningeal metastases (LM) are frequent in epidermal growth factor receptor (EGFR)-mutated non-small cell lung cancer (NSCLC), and are correlated with poor outcomes. In this study, we evaluated the efficacy of single-agent furmonertinib 160 mg or combining with anti-angiogenic agent in NSCLC patients who had developed BM/LM progression from previous tyrosine kinase inhibior (TKI) treatment. METHODS: EGFR-mutated NSCLC patients who developed BM (the BM cohort) or LM progression (the LM cohort) were included, having received furmonertinib 160 mg daily as second-line or later treatment, with or without anti-angiogenic agents. The intracranial efficacy was evaluated by intracranial progression-free survival (iPFS). RESULTS: Totally 12 patients in the BM cohort and 16 patients in the LM cohort were included. Almost one half of patients in the BM cohort and a majority in the LM cohort had a poor physical status, with a Eastern Cooperative Oncology Group performance status (ECOG-PS) ≥2. The administration of single-agent furmonertinib or combination treatment achieved a median iPFS of 3.6 months (95%CI 1.435-5.705) in the BM cohort, and 4.3 months (95%CI 2.094-6.486) in the LM cohort. Subgroup and univariate analysis has shown that a good ECOG-PS correlated with a favorable efficacy of furmonertinib in the BM cohort (median iPFS = 2.1 with ECOG-PS ≥ 2 vs. 14.6 months with ECOG-PS < 2, P < 0.05). Overall, any grade of adverse events (AEs) occured in 46.4% of patients (13/28). Among them, 14.3% of patients (4 of 28) had grade 3 or higher AEs, and were all under control, led to no dose reductions or suspension. CONCLUSION: Single-agent furmonertinib 160 mg or in combination of anti-angiogenic agent is an optional salvage therapy for advanced NSCLC patients who developed BM/LM progression from prior EGFR-TKI treatment, with a promising efficacy and an acceptable safety profile, and is worth of further exploration.

Sequencing strategies with ramucirumab and docetaxel following prior treatments for advanced non-small cell lung cancer: a multicenter retrospective cohort study.

OBJECTIVES: Ramucirumab (RAM) and docetaxel (DOC) are commonly used after first-line therapy for advanced non-small cell lung cancer (NSCLC). Therefore, we aimed to elucidate sequencing strategies of RAM and DOC following prior treatments, including immune checkpoint inhibitor (ICI), cytotoxic agent (CTx) alone, bevacizumab (BEV), and tyrosine kinase inhibitor (TKI). METHODS: We recruited patients with NSCLC who received RAM and DOC and compared the groups with and without prior ICI, CTx alone, BEV, and TKI, respectively. By tumor response to such treatments, the patients were further classified into "complete response (CR) + partial response (PR)," "stable disease," and "progressive disease" groups, respectively. We compared RAM and DOC efficacy among these groups. RESULTS: In total, 237 patients were registered. In the group with prior ICI, the objective response rate and disease control rate were significantly higher than those without prior ICI (p = 0.012 and 0.028, respectively), and the median progression-free survival (PFS) was also significantly longer (p = 0.027). There were no significant differences in PFS between the groups with and without CTx alone, BEV, and TKI. Multivariate analysis revealed that prior ICI was an independent factor associated with better PFS. Furthermore, the prior ICI group with CR + PR significantly prolonged PFS compared to the group without prior ICI (p = 0.013). CONCLUSION: RAM and DOC may be preferably administered after ICI, rather than after CTx alone, BEV, or TKI, and, furthermore, enhanced if the prior ICI has a favorable tumor response.

IL-8 and its role as a potential biomarker of resistance to anti-angiogenic agents and immune checkpoint inhibitors in metastatic renal cell carcinoma.

The therapeutic armamentarium of metastatic Renal Cell Carcinoma (mRCC) has consistently expanded in recent years, with the introduction of VEGF/VEGFR (Vascular Endothelial Growth Factor/Vascular Endothelial Growth Factor Receptor) inhibitors, mTOR (mammalian Target Of Rapamycin) inhibitors and Immune Checkpoint (IC) inhibitors. Currently, for the first-tline treatment of mRCC it is possible to choose between a VEGFR-TKI (VEGFR-Tyrosine Kinase Inhibitor) monotherapy, an ICI-ICI (Immune Checkpoint Inhibitor) combination and an ICI-VEGFRTKI combination. However, a consistent part of patients does not derive benefit from first-line therapy with ICIs; moreover, the use of combination regimens exposes patients to significant toxicities. Therefore, there is a critical need to develop prognostic and predictive biomarkers of response to VEGFR-TKIs and ICIs, and measurement of serum IL-8 is emerging as a potential candidate in this field. Recent retrospective analyses of large phase II and phase III trials found that elevated baseline serum IL-8 correlated with higher levels of tumor and circulating immunosuppressive myeloid cells, decreased T cell activation and poor response to treatment. These findings must be confirmed in prospective clinical trials; however, they provide evidence for a potential use of serum IL-8 as biomarker of resistance to VEGFR-TKIs and ICIs. Considering the amount of new agents and treatment regimens which are transforming the management of metastatic renal cell carcinoma, serum IL-8 could become a precious resource in tailoring the best therapy for each individual patient with the disease.

Effect of smoking habits on the efficacy of EGFR-TKI plus anti-angiogenic agent in advanced EGFR-mutant NSCLC.

BACKGROUND: The types of epidermal growth factor receptor (EGFR)-mutant non-small-cell lung cancer (NSCLC) patients who could obtain significant clinical benefit from the dual inhibition of EGFR/vascular EGFR (VEGFR) pathways remain unclear. No consensus has been reached on the significance of smoking habits in clinical benefit obtained from EGFR-TKI plus anti-angiogenic agents. METHODS: PubMed, EMBASE, and Cochrane databases for all phase II/III randomized clinical trials (RCTs) investigating the efficacy of EGFR-TKI combined with anti-angiogenic agents stratified by smoking habits (updated October 2021) were searched systematically. The primary outcomes were the pooled HRs for PFS/OS in smokers and non-smokers, and differences in efficacy of EGFR-TKI plus anti-angiogenic treatment between smokers and non-smokers, measured by difference in PFS and OS. RESULTS: Seven phase II/III RCTs involving 1452 patients were identified. The pooled analysis demonstrated that EGFR-TKI plus anti-angiogenic agent could decrease the risk of progression by 40% (HR, 0.60; 95%CI 0.48-0.75) in smokers when compared with EGFR-TKI alone, but not in non-smokers (HR, 0.92; 95%CI 0.68-1.25). The comparison analysis further demonstrated that EGFR-mutated NSCLC patients who smoked obtained greater progression-free survival (PFS) benefit from treatment with EGFR-TKI plus anti-angiogenic agents (HR, 0.68; 95%CI 0.51-0.91). Consistent with the results for PFS, smokers receiving EGFR-TKI plus anti-angiogenic agents appeared to exhibit better overall survival (OS) than non-smokers but not to a statistically significant degree (HR, 0.60; 95%CI 0.23-1.52). Meta-regression analysis revealed no significant effect of the line of treatment (P = 0.52), trial phase (P = 0.52), EGFR-TKI type (P = 0.13), or anti-angiogenic agent type (P = 0.50) on PFS effect sizes under multivariate models. CONCLUSION: Comprehensive analysis suggested that EGFR-TKI plus anti-angiogenic agents led to favorable PFS among smoking EGFR-mutant patients, comparable to nonsmokers, which might provide a useful guide for clinicians.

Anti-Angiogenic Agent Combined with Anti-PD-1 Immunotherapy Showed Activity in Patients With Classical Hodgkin Lymphoma Who Have Failed Immunotherapy: A Retrospective Case Report Study.

Background: PD-1/PD-L1 inhibitor immunotherapy has showed impressive activity in various cancers, especially relapsed/refractory (r/r) classical Hodgkin lymphoma (cHL). However, acquired resistance is inevitable for most patients. Sometimes severe side effects also lead to treatment termination. When immunotherapy failed, alternative treatment options are limited. In the past few years, we have used the anti-angiogenic agent apatinib and PD-1 inhibitor camrelizumab to treat cHL patients who failed prior immunotherapy. In this study, we analyzed the data of these patients. Patients and Methods: Patients with r/r cHL who had failed immunotherapy and subsequently received apatinib-camrelizumab (AC) combination therapy were included in this study. Patient data were collected from medical records and follow-up system. The efficacy and safety of AC therapy were analyzed. Results: Seven patients who failed immunotherapy were identified in our database, of which five patients acquired immunotherapy resistance and two patients experienced severe side effects. They received a combination of camrelizumab (200 mg every four weeks) and apatinib (425 mg or 250 mg per day). As of the cut-off date, these patients had received a median of 4 cycles (range, 2 - 31) of treatment. Two (2/7) patients achieved complete response, four (4/7) partial response, and one (1/7) stable disease. The median progression-free survival was 10.0 months (range, 2.0 - 27.8). Low-dose apatinib (250 mg) plus camrelizumab was well tolerated and had no unexpected side effects. Besides, no reactive cutaneous capillary endothelial proliferation was observed in AC-treated patients. Conclusions: Low dose apatinib plus camrelizumab might be a promising treatment option for r/r cHL patients who have failed immunotherapy. This combination treatment is worthy of further investigation in more patients including solid cancer patients who have failed immunotherapy.

Neo-Fs Index: A Novel Immunohistochemical Biomarker Panel Predicts Survival and Response to Anti-Angiogenetic Agents in Clear Cell Renal Cell Carcinoma.

Background: Frameshift indels have emerged as a predictor of immunotherapy response but were not evaluated yet to predict anti-angiogenetic agent (AAA) response or prognosis in clear cell renal cell carcinoma (ccRCC). Methods: Here, to develop biomarkers that predict survival and response to AAA, we evaluated the immunohistochemical expression of proteins whose genes frequently harbor frameshift indels in 638 ccRCC patients and correlated the individual and integrated markers with prognosis and AAA response. The mutational landscape was evaluated using targeted next-generation sequencing in 12 patients concerning protein markers. Immune gene signatures were retrieved from TCGA RNA seq data. Results: Five proteins (APC, NOTCH1, ARID1A, EYS, and filamin A) were independent adverse prognosticators and were incorporated into the Neo-fs index. Better overall, disease-specific and recurrence-free survival were observed with high Neo-fs index in univariate and multivariate survival analyses. Better AAA responses were observed with a high Neo-fs index, which reflected increased MHC class I, CD8+ T cell, cytolytic activity, and plasmacytoid dendritic cell signatures and decreased type II-IFN response signatures, as well as greater single-nucleotide variant (SNV) and indel counts. Conclusions: Neo-fs index, reflecting antitumor immune signature and more SNVs. and indels, is a powerful predictor of survival and AAA response in ccRCC.

Camrelizumab plus apatinib successfully treated a patient with advanced esophageal squamous cell carcinoma.

Aim: Advanced esophageal squamous cell carcinoma (ESCC) is a lethal disease with poor response to conventional chemotherapy. Immunotherapy showed better activity than chemotherapy in late-line treatment. However, the rate and duration of response are far from satisfactory. The efficacy of an anti-angiogenic agent combined with immunotherapy for ESCC is unknown. Results: A patient with ESCC experienced disease relapse after chemo-radiotherapy. The disease progressed after combined chemotherapy. A combination regimen of the PD-1 inhibitor camrelizumab and the anti-angiogenic agent apatinib was administered. The patient achieved a PET/CT-confirmed durable complete response with mild toxicity. Conclusion: The PD-1 inhibitor combined with the anti-angiogenic agent is effective and safe for the treatment of ESCC. This regimen is worth investigation in clinical trials.

Medication-related osteonecrosis of the jaws associated with intravitreal administration of ranibizumab.

Medication-related osteonecrosis of the jaws (MRONJ) is a well-known complication that, in the majority of cases, is related to antiresorptive agents. Numerous articles have described cases of MRONJ in bisphosphonate-naïve patients treated with anti-angiogenic agents administered via various routes. A single case of MRONJ after intravitreal injection of bevacizumab has been reported. We report a case of MRONJ after intravitreal injection of a different anti-angiogenic agent - ranibizumab - for the treatment of neovascular age-related macular degeneration, in a bisphosphonate-naïve patient. Although it may be a rare complication, patients treated with multiple doses of anti-angiogenic agents should be monitored for the possible early diagnosis of MRONJ.

To be or not to be: whether anti-angiogenic agent combined with immune checkpoint inhibitoris necessary in the treatment of advanced or metastatic renal cell carcinoma.

Although it's widely known that targeted therapy against angiogenesis and immunotherapy agents showed survival benefit over chemoradiotherapy in advanced or metastatic renal cell carcinoma, some patients still cannot receive a satisfied prognosis. We performed a systematic review and meta-analysis to explore the efficacy and safety of anti-angiogenic agents combined with immune checkpoint inhibitors. We conducted a search for randomized controlled trials in Pubmed, Embase, Cochrane, and major conference. Enrolled eligible studies and extracted data were completed by two investigators to compare OS, PFS, and ORR both in PD-L1 and ITT subset. Then, we calculated the pooled RR and 95% CI of all-grade and high-grade adverse effects to study its safety. Besides, we assessed the heterogeneity through subgroup and sensitivity analysis. A total of three RCTs covering 2662 patients were enrolled. In PFS analysis, the estimated HR for ITT subset was 0.74 with 95% CI of 0.65 to 0.84 and for PD-L1 subset was 0.65 with 95% CI of 0.56 to 0.76. And in OS analysis, the result was 0.74 with 95% CI of 0.53 to 1.03 in ITT subset and 0.74 with 95% CI of 0.56 to 0.96 in PD-L1 subset. As for ORR analysis, combination therapy showed advantage rather than monotherapy in ITT subset (RR 1.54; 95% CI 1.11 to 2.14), but conversely in PD-L1 positive subset (RR 1.64; 95% CI 0.94 to 2.84). Additionally, combination therapy failed to show obvious safety in most immune-related adverse events, whatever in all-grade or high grade.

Apatinib for treatment of a pseudomyxoma peritonei patient after surgical treatment and hyperthermic intraperitoneal chemotherapy: A case report.

BACKGROUND: Pseudomyxoma peritonei (PMP) is a rare benign, but progressive, disease according to myxoma histopathology. Surgical resection is the preferred and most effective treatment, but the outcomes are often unsatisfactory. CASE SUMMARY: A 63-year-old Chinese woman with PMP received apatinib at a daily dose of 0.5 mg for 15 d per cycle and at a daily dose of 0.4 mg to date for recurrent abdominal distension after surgical treatment and hyperthermic intraperitoneal chemotherapy. During the follow-up period, apatinib was the maintenance treatment with a progression-free period of 10 mo and the toxicity of apatinib was controllable and tolerable. Unfortunately, recurrence occurred 10 mo after administration. After two operations, the patient gave up treatment at the 18th mo and eventually died of intestinal obstruction and multiple organ failure. CONCLUSION: Apatinib may be an option for recurrent PMP after surgical treatment, but this conclusion remains to be confirmed.

Apatinib exhibits anti-leukemia activity in preclinical models of acute lymphoblastic leukemia.

BACKGROUND: Acute lymphoblastic leukemia (ALL) is a clonal malignant disorder characterized by an uncontrolled proliferation of immature B or T lymphocytes. Extensive studies have suggested an involvement of angiogenesis signaling in ALL progression and resistance to treatment. Thus, targeting angiogenesis with anti-angiogenic drugs may be a promising approach for ALL treatment. In this study, we investigated the effectiveness of Apatinib, a novel receptor tyrosine kinase inhibitor selectively targeting VEGFR-2 in ALL cells. METHOD: ALL cell lines were treated with different concentration of Apatinib and then CCK8 assay, flow cytometry were used to determine the IC50 value and cell apoptosis, respectively. The effect of Apatinib against primary ALL cells from 11 adult patients and normal counterparts were also analyzed by apoptosis with flow cytometry. Next, we used western bolting and mass cytometry (CyTOF) assay to explore the underlying mechanism of the cytotoxicity of Apatinib. Finally, the anti-leukemia activity was further evaluated in an in vivo xenograft model of ALL. RESULTS: Our results showed that Apatinib significantly inhibited cell growth and promoted apoptosis in both B and T lineage ALL cell lines in a dose- and time-dependent manner. The IC50 values of Apatinib against Nalm6, Reh, Jurkat and Molt4 for 48 h were 55.76 ± 13.19, 51.53 ± 10.74, 32.43 ± 5.58, 39.91 ± 9.88 µmol/L, and for 72 h were 30.34 ± 2.65, 31.96 ± 3.92, 17.62 ± 5.90, and 17.65 ± 2.17 µmol/L respectively. Similarly, Apatinib shows cytotoxic activity against primary adult ALL cells while sparing their normal counterparts in vitro. Moreover, Apatinib suppressed ALL growth and progression in an in vivo xenograft model. Mechanistically, Apatinib-induced cytotoxicity was closely associated with inhibition of VEGFR2 and its downstream signaling cascades, including the PI3 K, MAPK and STAT3 pathways. CONCLUSION: Our study indicates that Apatinib exerts its anti-leukemia effect by inducing apoptosis through suppressing the VEGFR2 signaling pathway, supporting a potential role for Apatinib in the treatment of ALL.

Survival benefit of anti-angiogenic agents in patients with previously treated advanced gastric or gastroesophageal junction cancer: a meta-analysis.

There is a debate as to whether anti-angiogenic molecular agents can produce survival benefits in patients with previously treated advanced gastric cancer (GC) or gastroesophageal junction cancer (GEJC). We performed this meta-analysis of randomized trials to evaluate the survival outcomes of an anti-angiogenic agent versus placebo in the salvage treatment of advanced GC or GEJC. Electronic databases were searched for eligible studies. From the four studies, 910 patients with previously treated advanced GC or GEJC were included in the meta-analysis. Compared with placebo, anti-angiogenic targeted agents significantly improved progression-free survival (hazard ratio = 0.37 [95% confidence interval, 0.26-0.53], P < 0.00001). In terms of overall survival, anti-angiogenic agents induced 36% reduction in the risk for death (hazard ratio = 0.64 [95% confidence interval, 0.48-0.86], P = 0.002). In conclusion, this meta-analysis demonstrates that anti-angiogenic agents can prolong survival in patients with previously treated advanced GC or GEJC. This finding suggests that anti-angiogenic therapy can be a considerable option in patients who are not candidates for further chemotherapy.

Realizing the Potential of Vascular Targeted Therapy: The Rationale for Combining Vascular Disrupting Agents and Anti-Angiogenic Agents to Treat Cancer.

Vascular targeted therapies (VTTs) are agents that target tumor vasculature and can be classified into two categories: those that inhibit angiogenesis and those that directly interfere with established tumor vasculature. Although both the anti-angiogenic agents (AAs) and the vascular disrupting agents (VDAs) target tumor vasculature, they differ in their mechanism of action and therapeutic application. Combining these two agents may realize the full potential of VTT and produce an effective therapeutic regimen. Here, we review AAs and VDAs (monotherapy and in combination with conventional therapies). We also discuss the rationale of combined VTT and its potential to treat cancer.

Phase I trial and pharmacokinetic study of tanibirumab, a fully human monoclonal antibody to vascular endothelial growth factor receptor 2, in patients with refractory solid tumors.

Background Tanibirumab is a fully human monoclonal antibody to vascular endothelial growth factor receptor 2 (VEGFR-2). We conducted a first-in-human phase I study of tanibirumab in patients with solid tumors refractory to standard chemotherapy. Primary endpoints were evaluating safety, pharmacokinetics (PKs), estimating maximum-tolerated dose (MTD) and recommended phase II dose (RP2D). Methods We designed our study to escalate tanibirumab at 9 different dose levels with a 3 + 3 method and tanibirumab (1-28 mg/kg) was administered intravenously on D1, 8, 15 in 28-day courses. Dose limiting toxicities (DLTs) were only assessed during the first cycle of treatment and response evaluation was performed every 2 cycles. The effects of tanibirumab on several angiogenic factors were analyzed. Results From October 2011 to September 2013, a total of 26 patients with refractory solid tumors were enrolled. The median age was 58 years (range, 27-75) and 20 patients were male. The most common tumor type was colorectal cancer (N = 19) and seven patients had a history of previous bevacizumab treatment. As hemangioma continued to occur, the final dose level, 28 mg/kg, was not performed. DLTs were not found, and the MTD was confirmed to be 24 mg/kg. Hemangioma was observed in 16 patients (61.5%), but all were grade 1-2 and disappeared after discontinuation of the study drug. Among the 18 patients in the efficacy set, no objective response was observed, but 11 patients showed stable disease. PKs were characterized by dose-dependent linear exposure and the mean trough concentrations exceeded biologically relevant target levels at 12 mg/kg and above. Serum VEGF, soluble VEGFR-2, and PlGF increased at the 4 mg/kg dose level and above. Conclusions Treatment with tanibirumab showed a tolerable toxicity profile and modest clinical efficacy in patients with refractory solid tumors. A phase II trial of tanibirumab is ongoing now.

The development and use of vascular targeted therapy in ovarian cancer.

Combination vascular-targeted therapies (VTTs) represent a promising approach for patients with platinum-resistant recurrent ovarian cancer (OC). VTTs include two mechanistically distinct classes of agents: anti-angiogenic agents (AAs) and vascular-disrupting agents (VDAs). AAs suppress growth of new tumor vasculature through inhibition of vascular endothelial growth factor (VEGF) and other pro-angiogenic molecules. Bevacizumab, a monoclonal antibody that binds to VEGF, has improved progression-free survival (PFS) when given with chemotherapy in patients with advanced OC. VDAs target the established tumor vascular network, inducing vessel occlusion, shutdown of circulation, and widespread necrosis within the tumor interior - a region often resistant to conventional chemotherapy and radiation. Tubulin-binding VDAs such as BNC105P, ombrabulin, and combretastatin A4-phosphate (CA4P) have been studied for the treatment of OC. These agents act by binding tubulin in the endothelial cells of tumor vessels, triggering cytoskeletal disruption, altering cellular shape, and destabilizing cell-cell junctions, which lead to increased vascular leakage and, ultimately, to disruption of blood flow. Fundamental differences between the vascular networks of tumors and those of normal tissues allow these agents to selectively reduce tumor circulation while having little effect on non-malignant tissues. Animal studies and clinical trials show enhanced efficacy when VDAs are combined with chemotherapy as well as AAs. The latter combination allows targeting of different aspects of the tumor vasculature, a strong rationale for combining these two drug classes into a single regimen. CA4P is the only VDA in active development for OC. In a phase II trial of patients with recurrent OC, CA4P added to bevacizumab improved PFS compared with bevacizumab alone. The phase II, placebo-controlled PAZOFOS trial (NCT02055690) is evaluating the effects of CA4P plus the anti-angiogenic agent pazopanib in recurrent OC. FOCUS, a phase II/III, placebo-controlled trial (NCT02641639), is currently evaluating CA4P plus bevacizumab and chemotherapy in platinum-resistant OC.

Comparison of the crystal structures of the potent anticancer and anti-angiogenic agent regorafenib and its monohydrate.

Regorafenib {systematic name: 4-[4-({[4-chloro-3-(trifluoromethy)phenyl]carbamoyl}amino)-3-fluorophenoxy]-1-methylpyridine-2-carboxamide}, C21H15ClF4N4O3, is a potent anticancer and anti-angiogenic agent that possesses various activities on the VEGFR, PDGFR, raf and/or flt-3 kinase signaling molecules. The compound has been crystallized as polymorphic form I and as the monohydrate, C21H15ClF4N4O3·H2O. The regorafenib molecule consists of biarylurea and pyridine-2-carboxamide units linked by an ether group. A comparison of both forms shows that they differ in the relative orientation of the biarylurea and pyridine-2-carboxamide units, due to different rotations around the ether group, as measured by the C-O-C bond angles [119.5 (3)° in regorafenib and 116.10 (15)° in the monohydrate]. Meanwhile, the conformational differences are reflected in different hydrogen-bond networks. Polymorphic form I contains two intermolecular N-H...O hydrogen bonds, which link the regorafenib molecules into an infinite molecular chain along the b axis. In the monohydrate, the presence of the solvent water molecule results in more abundant hydrogen bonds. The water molecules act as donors and acceptors, forming N-H...O and O-H...O hydrogen-bond interactions. Thus, R4(2)(28) ring motifs are formed, which are fused to form continuous spiral ring motifs along the a axis. The (trifluoromethyl)phenyl rings protrude on the outside of these motifs and interdigitate with those of adjacent ring motifs, thereby forming columns populated by halogen atoms.