Dirk Laurent

Regorafenib monotherapy for previously treated metastatic colorectal cancer (CORRECT): an international, multicentre, randomised, placebo-controlled, phase 3 trial

BACKGROUND No treatment options are available for patients with metastatic colorectal cancer that progresses after all approved standard therapies, but many patients maintain a good performance status and could be candidates for further therapy. An international phase 3 trial was done to assess the multikinase inhibitor regorafenib in these patients. METHODS We did this trial at 114 centres in 16 countries. Patients with documented metastatic colorectal cancer and progression during or within 3 months after the last standard therapy were randomised (in a 2:1 ratio; by computer-generated randomisation list and interactive voice response system; preallocated block design (block size six); stratified by previous treatment with VEGF-targeting drugs, time from diagnosis of metastatic disease, and geographical region) to receive best supportive care plus oral regorafenib 160 mg or placebo once daily, for the first 3 weeks of each 4 week cycle. The primary endpoint was overall survival. The study sponsor, participants, and investigators were masked to treatment assignment. Efficacy analyses were by intention to treat. This trial is registered at ClinicalTrials.gov, number NCT01103323. FINDINGS Between April 30, 2010, and March 22, 2011, 1052 patients were screened, 760 patients were randomised to receive regorafenib (n=505) or placebo (n=255), and 753 patients initiated treatment (regorafenib n=500; placebo n=253; population for safety analyses). The primary endpoint of overall survival was met at a preplanned interim analysis; data cutoff was on July 21, 2011. Median overall survival was 6·4 months in the regorafenib group versus 5·0 months in the placebo group (hazard ratio 0·77; 95% CI 0·64-0·94; one-sided p=0·0052). Treatment-related adverse events occurred in 465 (93%) patients assigned regorafenib and in 154 (61%) of those assigned placebo. The most common adverse events of grade three or higher related to regorafenib were hand-foot skin reaction (83 patients, 17%), fatigue (48, 10%), diarrhoea (36, 7%), hypertension (36, 7%), and rash or desquamation (29, 6%). INTERPRETATION Regorafenib is the first small-molecule multikinase inhibitor with survival benefits in metastatic colorectal cancer which has progressed after all standard therapies. The present study provides evidence for a continuing role of targeted treatment after disease progression, with regorafenib offering a potential new line of therapy in this treatment-refractory population. FUNDING Bayer HealthCare Pharmaceuticals.

Efficacy and safety of regorafenib for advanced gastrointestinal stromal tumours after failure of imatinib and sunitinib (GRID): an international, multicentre, randomised, placebo-controlled, phase 3 trial.

BACKGROUND Until now, only imatinib and sunitinib have proven clinical benefit in patients with gastrointestinal stromal tumours (GIST), but almost all metastatic GIST eventually develop resistance to these agents, resulting in fatal disease progression. We aimed to assess efficacy and safety of regorafenib in patients with metastatic or unresectable GIST progressing after failure of at least imatinib and sunitinib. METHODS We did this phase 3 trial at 57 hospitals in 17 countries. Patients with histologically confirmed, metastatic or unresectable GIST, with failure of at least previous imatinib and sunitinib were randomised in a 2:1 ratio (by computer-generated randomisation list and interactive voice response system; preallocated block design (block size 12); stratified by treatment line and geographical region) to receive either oral regorafenib 160 mg daily or placebo, plus best supportive care in both groups, for the first 3 weeks of each 4 week cycle. The study sponsor, participants, and investigators were masked to treatment assignment. The primary endpoint was progression-free survival (PFS). At disease progression, patients assigned placebo could crossover to open-label regorafenib. Analyses were by intention to treat. This trial is registered with ClinicalTrials.gov, number NCT01271712. RESULTS From Jan 4, to Aug 18, 2011, 240 patients were screened and 199 were randomised to receive regorafenib (n=133) or matching placebo (n=66). Data cutoff was Jan 26, 2012. Median PFS per independent blinded central review was 4·8 months (IQR 1·4-9·2) for regorafenib and 0·9 months (0·9-1·8) for placebo (hazard ratio [HR] 0·27, 95% CI 0·19-0·39; p<0·0001). After progression, 56 patients (85%) assigned placebo crossed over to regorafenib. Drug-related adverse events were reported in 130 (98%) patients assigned regorafenib and 45 (68%) patients assigned placebo. The most common regorafenib-related adverse events of grade 3 or higher were hypertension (31 of 132, 23%), hand-foot skin reaction (26 of 132, 20%), and diarrhoea (seven of 132, 5%). INTERPRETATION The results of this study show that oral regorafenib can provide a significant improvement in progression-free survival compared with placebo in patients with metastatic GIST after progression on standard treatments. As far as we are aware, this is the first clinical trial to show benefit from a kinase inhibitor in this highly refractory population of patients. FUNDING Bayer HealthCare Pharmaceuticals.

Phase I Study of the Safety, Tolerability, Pharmacokinetics, and Pharmacodynamics of PTK787/ZK 222584 Administered Twice Daily in Patients With Advanced Cancer

PURPOSE PTK787/ZK 222584 (PTK/ZK) is an oral angiogenesis inhibitor targeting all known vascular endothelial growth factor (VEGF) receptor tyrosine kinases, including VEGFR-1/Flt-1, VEGFR-2/KDR, VEGFR-3/Flt-4, the platelet-derived growth factor receptor tyrosine kinase, and the c-kit protein tyrosine kinase. In this phase I dose-escalating study, PTK/ZK was administered bid to exploit the theoretical advantage of maintaining constant drug levels above a threshold known from preclinical data to interfere with VEGF receptor signaling. PATIENTS AND METHODS Forty-three patients with advanced cancers received single-agent PTK/ZK at doses of 150 to 1,000 mg orally bid. Assessments for safety and pharmacokinetics were performed. Dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) was used as a pharmacodynamic marker of response. RESULTS At 1,000 mg bid, the dose-limiting toxicity of reversible grade 3 lightheadedness was observed. Dose-related grade 3 fatigue and vomiting were observed but these were not dose-limiting. Pharmacokinetic data confirmed that PTK/ZK exposure increased with increasing dose up to 500 mg bid and appeared to plateau at higher doses. A greater than 40% reduction in the DCE-MRI bidirectional transfer constant (K(i)) at day 2 predicted for nonprogression of disease. CONCLUSION The maximum-tolerated oral dose of PTK/ZK is 750 mg orally bid. DCE-MRI and pharmacokinetic data indicate that PTK/ZK >/= 1,000 mg total daily dose is the biologically active dose.

Randomized, Placebo-Controlled, Phase III Study of First-Line Oxaliplatin-Based Chemotherapy Plus PTK787/ZK 222584, an Oral Vascular Endothelial Growth Factor Receptor Inhibitor, in Patients With Metastatic Colorectal Adenocarcinoma

PURPOSE PTK787/ZK 222584 (PTK/ZK; vatalanib), an orally active, multitargeted angiogenesis inhibitor, has shown tolerability and promising activity in early-phase studies, which led to a phase III trial in combination with oxaliplatin, fluorouracil, and leucovorin (FOLFOX4). PATIENTS AND METHODS Patients (N = 1,168) with previously untreated metastatic colorectal cancer were randomly assigned 1:1 to receive FOLFOX4 plus PTK/ZK or placebo (ClinicalTrials.gov identifier: NCT00056459). Stratification factors included WHO performance status (0 v 1 or 2) and serum lactate dehydrogenase (LDH; ≤ v > 1.5× the upper limit of normal). The primary end point was progression-free survival (PFS). Secondary end points included overall survival (OS) and overall response rate (ORR). RESULTS PFS, OS, and ORR were not statistically improved with PTK/ZK (P > .05). Median PFS by central review was 7.7 months with PTK/ZK versus 7.6 months with placebo (hazard ratio [HR], 0.88; 95% CI, 0.74 to 1.03; P = .118); median OS was 21.4 months with PTK/ZK versus 20.5 months with placebo (HR, 1.08; 95% CI, 0.94 to 1.24; P = .260). In an exploratory post hoc analysis of PFS in patients (n = 158 per arm) with high serum LDH, a potential marker of hypoxia, PFS was longer with PTK/ZK versus placebo (7.7 v 5.8 months, respectively; HR, 0.67; 95% CI, 0.49 to 0.91; P = .009). CONCLUSION Although the efficacy objectives of this study were not met, a subgroup of patients who may potentially benefit from small-molecule vascular endothelial growth factor receptor inhibitor therapy has been identified and further research is warranted.

Vascular endothelial growth factor receptor tyrosine kinase inhibitors: PTK787/ZK 222584 ☆ ☆☆

PTK787/ZK 222584 (PTK/ZK) is an oral potent and selective inhibitor of the vascular endothelial growth factor (VEGF)-mediated Flt-1 and KDR receptor tyrosine kinases. PTK/ZK has been shown to reduce growth and microvasculature in subcutaneously implanted human tumor xenografts in nude mice. A clinical difficulty in evaluating angiogenesis inhibitors has been the usefulness of conventional study endpoints. Therefore, dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) has been studied as a pharmacodynamic marker of efficacy of PTK/ZK. Phase I studies are under way evaluating the optimum dose and schedule of oral PTK/ZK administered continuously to patients with advanced cancers of types known to overexpress VEGF. To date, particularly in patients with liver metastases from colorectal cancer treated with PTK/ZK, DCE-MRI has been a useful predictor of the biological response of VEGF-receptor inhibition. Toxicities have been manageable and have included lightheadedness, ataxia, nausea, vomiting, and hypertension. Stabilization of disease for >/= 6 months has been seen in heavily pretreated patients receiving PTK/ZK at higher doses. Preliminary data suggest that PTK/ZK can be administered safely on a continuous daily dosing schedule, efficacy data look promising, and DCE-MRI correlates with biological response. DCE-MRI will be used to guide dose optimization of PTK/ZK and perhaps of other angiogenesis inhibitors in future studies.

Analysis of circulating DNA and protein biomarkers to predict the clinical activity of regorafenib and assess prognosis in patients with metastatic colorectal cancer: A retrospective, exploratory analysis of the CORRECT trial

BACKGROUND Tumour mutational status is an important determinant of the response of metastatic colorectal cancer to targeted treatments. However, the genotype of the tissue obtained at the time of diagnosis might not accurately represent tumour genotype after multiple lines of treatment. This retrospective exploratory analysis investigated the clinical activity of regorafenib in biomarker subgroups of the CORRECT study population defined by tumour mutational status or plasma protein levels. METHODS We used BEAMing technology to identify KRAS, PIK3CA, and BRAF mutations in DNA obtained from the plasma of 503 patients with metastatic colorectal cancer who enrolled in the CORRECT trial. We quantified total human genomic DNA isolated from plasma samples for 503 patients using a modified version of human long interspersed nuclear element-1 (LINE-1) quantitive real-time PCR. We also measured the concentration of 15 proteins of interest-angiopoietin 2, interleukin 6, interleukin 8, placental growth factor, soluble TIE-1, soluble VEGFR1, VEGF-A, VEGF-C, VEGF-D, VEGF-A isoform 121, bone morphogenetic protein 7, macrophage colony-stimulating factor, stromal cell-derived factor-1, tissue inhibitor of metalloproteinase 2, and von Willebrand factor-in plasma samples from 611 patients. We did correlative analyses of overall survival and progression-free survival in patient subgroups based on mutational status, circulating DNA concentration, and protein concentrations. The CORRECT trial was registered with ClinicalTrials.gov, number NCT01103323. FINDINGS Tumour-associated mutations were readily detected with BEAMing of plasma DNA, with KRAS mutations identified in 349 (69%) of 503 patients, PIK3CA mutations in 84 (17%) of 503 patients, and BRAF mutations in 17 (3%) of 502 patients. We did not do correlative analysis based on BRAF genotype because of the low mutational frequency detected for this gene. Some of the most prevalent individual hot-spot mutations we identified included: KRAS (KRAS G12D, 116 [28%] of 413 mutations; G12V, 72 [17%]; and G13D, 67 [16%]) and PIK3CA (PIK3CA E542K, 27 [30%] of 89 mutations; E545K, 37 [42%]; and H1047R, 12 [14%]). 41 (48%) of 86 patients who had received anti-EGFR therapy and whose archival tumour tissue DNA was KRAS wild-type in BEAMing analysis were identified as having KRAS mutations in BEAMing analysis of fresh plasma DNA. Correlative analyses suggest a clinical benefit favouring regorafenib across patient subgroups defined by KRAS and PIK3CA mutational status (progression-free survival with regorafenib vs placebo: hazard ratio [HR] 0·52, 95% CI 0·35-0·76 for KRAS wild-type; HR 0·51, 95% CI 0·40-0·65 for KRAS mutant [KRAS wild type vs mutant, pinteraction=0·74]; HR 0·50, 95% CI 0·40-0·63 for PIK3CA wild-type; HR 0·54, 95% CI 0·32-0·89 for PIK3CA mutant [PIK3CA wild-type vs mutant, pinteraction=0·85]) or circulating DNA concentration (progression-free survival with regorafenib vs placebo: HR 0·53, 95% CI 0·40-0·71, for low circulating DNA concentrations; HR 0·52, 95% CI 0·40-0·70, for high circulating DNA concentrations; low vs high circulating DNA, pinteraction=0·601). With the exception of von Willebrand factor, assessed with the median cutoff method, plasma protein concentrations were also not associated with regorafenib activity in terms of progression-free survival. In univariable analyses, the only plasma protein that was associated with overall survival was TIE-1, high concentrations of which were associated with longer overall survival compared with low TIE-1 concentrations. This association was not significant in multivariable analyses. INTERPRETATION BEAMing of circulating DNA could be a viable approach for non-invasive analysis of tumour genotype in real time and for the identification of potentially clinically relevant mutations that are not detected in archival tissue. Additionally, the results show that regorafenib seems to be consistently associated with a clinical benefit in a range of patient subgroups based on mutational status and protein biomarker concentrations. FUNDING Bayer HealthCare Pharmaceuticals.

Prognostic and Predictive Role of Lactate Dehydrogenase 5 Expression in Colorectal Cancer Patients Treated with PTK787/ZK 222584 (Vatalanib) Antiangiogenic Therapy

Purpose: The Colorectal Oral Novel therapy For the Inhibition of angiogenesis and Retarding of Metastases (CONFIRM)-randomized trials, investigating the role of the VEGF-receptor inhibitor PTK787/ZK 222584 (vatalanib) in colorectal cancer (FOLFOX 4 ± vatalanib), showed some benefit in patients with high serum lactate dehydrogenase (LDH) levels. Here, we investigated the expression of LDH5 (encoded entirely by the LDHA gene, regulated by the hypoxia inducible factors) in cancer tissues from patients recruited in the CONFIRM trials and relationship to response. Experimental Design: Paraffin-embedded materials from 179 patients recruited in the CONFIRM trials were analyzed by immunohistochemistry for the expression of the LDH5 protein. Correlations with serum LDH, response, and survival were assessed. Results: A significant association of tumor burden and of poor performance status (PS) with serum LDH was noted. Poor PS and high tumor LDH5 expression predicted for poor response rates. High tissue LDH5 was related to poor progression-free survival (PFS) only in the placebo group of patients, whereas the addition of vatalanib seemed to improved response and PFS in this subgroup. High serum LDH levels were linked with significantly poorer overall survival, which however was not sustained in multivariate analysis. Conclusions: Serum LDH and tissue LDH5 levels are complementary features that help to characterize the activity of LDH in colorectal cancer and have a potent value in predicting response to chemotherapy. The addition of vatalanib diminished the impact of LDH expression on the prognosis of patients. Clin Cancer Res; 17(14); 4892–900. ©2011 AACR.

Metabolism and Disposition of Vatalanib (PTK787/ZK-222584) in Cancer Patients

Vatalanib (PTK787/ZK-222584) is a new oral antiangiogenic molecule that inhibits all known vascular endothelial growth factor receptors. Vatalanib is under investigation for the treatment of solid tumors. Disposition and biotransformation of vatalanib were studied in an open-label, single-center study in patients with advanced cancer. Seven patients were given a single oral 14C-radiolabeled dose of 1000 mg of vatalanib administered at steady state, obtained after 14 consecutive daily oral doses of 1000 mg of nonradiolabeled vatalanib. Plasma, urine, and feces were analyzed for radioactivity, vatalanib, and its metabolites. Metabolite patterns were determined by high-performance liquid chromatography coupled to radioactivity detection with off-line microplate solid scintillation counting and characterized by LC-MS. Vatalanib was well tolerated. The majority of adverse effects corresponded to common toxicity criteria grade 1 or 2. Two patients had stable disease for at least 7 months. Plasma Cmax values of 14C radioactivity (38.3 ± 26.0 μM; mean ± S.D., n = 7) and vatalanib (15.8 ± 9.5 μM) were reached after 2 and 1.5 h (median), respectively, indicating rapid onset of absorption. Terminal elimination half-lives in plasma were 23.4 ± 5.5 h for 14C radioactivity and 4.6 ± 1.1 h for vatalanib. Vatalanib cleared mainly through oxidative metabolism. Two pharmacologically inactive metabolites, CGP-84368/ZK-260120 [(4-chlorophenyl)-[4-(1-oxy-pyridin-4-yl-methyl)-phthalazin-1-yl]-amine] and NVP-AAW378/ZK-261557 [rac-4-[(4-chloro-phenyl)amino]-α-(1-oxido-4-pyridyl)phthalazine-1-methanol], having systemic exposure comparable to that of vatalanib, contributed mainly to the total systemic exposure. Vatalanib and its metabolites were excreted rapidly and mainly via the biliary-fecal route. Excretion of radioactivity was largely complete, with a radiocarbon recovery between 67% and 96% of dose within 7 days (42–74% in feces, 13–29% in urine).

Vatalanib: the clinical development of a tyrosine kinase inhibitor of angiogenesis in solid tumours

The licensing of bevacizumab in patients with metastatic colorectal cancer has fuelled research in angiogenesis. Vatalanib (PTK787/ZK 222584), a potent oral tyrosine kinase inhibitor with a selective range of molecular targets, has been extensively investigated and has shown promising results in patients with colorectal cancer in early trials. Dynamic contrast-enhanced MRI has been useful as a pharmacodynamic tool to define the dose that has a biological effect. The primary objectives of the Phase III CONFIRM (Colorectal Oral Novel Therapy for the Inhibition of Angiogenesis and Retarding of Metastases in First-line) studies were not met. However, an interesting pre-planned subset analysis in both studies showed that patients with high lactate dehydrogenase derived clinical benefit. Although this type of analysis should always be considered with caution, the Phase III clinical programme of vatalanib is continuing with further innovative studies looking at other indications and schedules for vatalanib.

Phase II trial of PTK787/ZK 222584 (vatalanib) administered orally once-daily or in two divided daily doses as second-line monotherapy in relapsed or progressing patients with stage IIIB/IV non-small-cell lung cancer (NSCLC)

BACKGROUND The objective of this multicenter, prospective uncontrolled phase II trial was to determine efficacy, safety and tolerability of vatalanib, an oral angiogenesis inhibitor targeting all known vascular endothelial growth factor receptors, in the second-line treatment of non-small-cell lung cancer (NSCLC). PATIENTS AND METHODS Patients with stage IIIB/IV NSCLC-proven tumor progression during or after one platinum-based chemotherapy regimen received a fixed dose of 1250 mg vatalanib either once-daily dosing (QD) or two divided daily dosing (TDD: 500 mg a.m. + 750 mg p.m.) until disease progression or unacceptable toxicity. Primary end point was the disease control rate (DCR) at 12 weeks. RESULTS Fifty-four and 58 patients were enrolled to the QD and TDD arms. DCR at 12 weeks was 35% in the QD and 37% in the TDD arm. The best overall response included one (2%) patient with confirmed partial response with QD and three (5%) with TDD. Median progression-free survival and overall survival were 2.1/7.3 months in the QD arm and 2.8/9.0 months with TDD arm. This therapy showed a moderate toxicity profile for the majority of patients. CONCLUSIONS In the chosen patient population, vatalanib QD and TDD dosing demonstrated potential benefits in tumor size reduction, DCR, and survival.BACKGROUND The objective of this multicenter, prospective uncontrolled phase II trial was to determine efficacy, safety and tolerability of vatalanib, an oral angiogenesis inhibitor targeting all known vascular endothelial growth factor receptors, in the second-line treatment of non-small-cell lung cancer (NSCLC). PATIENTS AND METHODS Patients with stage IIIB/IV NSCLC-proven tumor progression during or after one platinum-based chemotherapy regimen received a fixed dose of 1250 mg vatalanib either once-daily dosing (QD) or two divided daily dosing (TDD: 500 mg a.m. + 750 mg p.m.) until disease progression or unacceptable toxicity. Primary end point was the disease control rate (DCR) at 12 weeks. RESULTS Fifty-four and 58 patients were enrolled to the QD and TDD arms. DCR at 12 weeks was 35% in the QD and 37% in the TDD arm. The best overall response included one (2%) patient with confirmed partial response with QD and three (5%) with TDD. Median progression-free survival and overall survival were 2.1/7.3 months in the QD arm and 2.8/9.0 months with TDD arm. This therapy showed a moderate toxicity profile for the majority of patients. CONCLUSIONS In the chosen patient population, vatalanib QD and TDD dosing demonstrated potential benefits in tumor size reduction, DCR, and survival.