A phase I dose-escalation study of regorafenib (BAY 73-4506), an inhibitor of oncogenic, angiogenic, and stromal kinases, in patients with advanced solid tumors

PURPOSE

Regorafenib is a novel oral multikinase inhibitor of angiogenic (VEGFR1-3, TIE2), stromal (PDGFR-β, FGFR), and oncogenic kinases (KIT, RET, and RAF). This first-in-man, phase I dose-escalation study assessed the safety, pharmacokinetic, pharmacodynamic, and efficacy profiles of regorafenib in patients with advanced solid tumors.

PATIENTS AND METHODS

Patients aged 18 years or older with advanced solid tumors refractory to standard treatment were recruited. Regorafenib was administered orally for 21 days on/seven days off in repeating cycles, until discontinuation due to toxicity or tumor progression. Adverse events (AE) were assessed using National Cancer Institute Common Terminology Criteria for Adverse Events v3.0. Pharmacokinetic profiles were measured after a single dose and on day 21. Pharmacodynamic and efficacy evaluations included tumor perfusion assessment using dynamic contrast-enhanced MRI, plasma cytokines, and tumor response using RECIST (v1.0).

RESULTS

Fifty-three patients were enrolled into eight cohorts at dose levels from 10 to 220 mg daily. The recommended dose for future studies was determined to be 160 mg daily, with a treatment schedule of 21 days on/seven days off in repeating 28-day cycles. The most common drug-related grade 3 or 4 AEs were dermatologic AEs (hand-foot skin reaction, rash), hypertension, and diarrhea. Pharmacokinetic analysis revealed a similar exposure at steady state for the parent compound and two pharmacologically active metabolites. Tumor perfusion and plasma cytokine analysis showed biologic activity of regorafenib. Three of 47 evaluable patients achieved a partial response (renal cell carcinoma, colorectal carcinoma, and osteosarcoma).

CONCLUSION

Regorafenib showed an acceptable safety profile and preliminary evidence of antitumor activity in patients with solid tumors.

Phase I study of telatinib (BAY 57-9352): analysis of safety, pharmacokinetics, tumor efficacy, and biomarkers in patients with colorectal cancer

BACKGROUND

Telatinib (BAY 57-9352) is an orally available, small-molecule inhibitor of vascular endothelial growth factor receptors 2 and 3 (VEGFR-2/-3) and platelet-derived growth factor receptor β tyrosine kinases.

METHODS

In this multicenter phase I dose-escalation study including a phase II like expansion part, 39 patients with refractory colorectal cancer (CRC) were enrolled into 14 days on / 7 days off in repeating cycles of 28 days (n = 11) or continuous dosing groups (n = 28) to receive ≥ 600 mg telatinib twice-daily (bid).

RESULTS

Hypertension (28%) and diarrhoea (15%) were the most frequent study drug-related adverse events of CTC grade 3. In this population, no clear relationship between telatinib dose and individual Cmax and AUC was apparent in the 600 mg bid to 1500 mg bid dose range. No partial remission according to RECIST was reached, but 41% of the patients reached some tumour shrinkage during treatment. Tumour blood flow measured by dynamic contrast-enhanced magnetic resonance imaging and sVEGFR-2 plasma levels decreased with increasing telatinib AUC(0-12).

CONCLUSION

Telatinib treatment was well tolerated. The observed single agent antitumor activity in heavily pretreated CRC patients was limited. Pharmacodynamic results are suggestive for the biological activity of telatinib justifying a further evaluation of telatinib bid in combination with standard chemotherapy regimens in CRC patients.

Vascular and pharmacokinetic effects of EndoTAG-1 in patients with advanced cancer and liver metastasis

BACKGROUND

EndoTAG-1 (ET), a novel formulation of cationic liposomes carrying embedded paclitaxel (Taxol), shows antitumoral activity, targeting tumor endothelial cells in solid tumors. Patients with advanced metastatic cancer were evaluated investigating effects on pharmacokinetics and tumor vasculature using dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) and contrast-enhanced ultrasound (CEUS).

PATIENTS AND METHODS

The pharmacokinetic (PK) profile of ET (22 mg/m(2) i.v.) was evaluated after single and repeated doses. DCE-MRI and CEUS explored hepatic metastases before, during and after the 4-week treatment cycle. Angiogenic biomarkers were assessed. Tumor response was evaluated by modified RECIST.

RESULTS

The PK profile demonstrated slight accumulation of paclitaxel after repeated doses. DCE-MRI parameters K(trans) and/or iAUC(60) showed a trend to decrease. Changes of blood flow-dependent parameters of DCE-MRI and CEUS were well correlated. Angiogenic biomarkers revealed no clear trend. ET was generally well tolerated; common toxic effects were fatigue and hypersensitivity reactions. Nine (9 of 18) patients had stable disease after the first treatment cycle. Four patients without disease progression continued treatment.

CONCLUSIONS

This study including multiple pretreated patients with different metastatic cancer revealed individually distinctive hemodynamic alterations by DCE-MRI. The PK profiles of ET were similar as observed previously.

DCE-MRI assessment of the effect of vandetanib on tumor vasculature in patients with advanced colorectal cancer and liver metastases: a randomized phase I study

BACKGROUND

Vandetanib is a once-daily oral inhibitor of VEGFR, EGFR and RET signaling pathways. In patients with advanced colorectal cancer and liver metastases, the effect of vandetanib on tumor vasculature was assessed using dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI).

METHODS

Eligible patients received vandetanib 100 or 300 mg/day. DCE-MRI (iAUC(60 )and K(trans)) was used to quantify the primary endpoints of tumor perfusion and vascular permeability. An exploratory assessment of tumor oxygenation was performed using MRI/T2*. All MRI parameters were measured at baseline (twice) and on days 2, 8, 29 and 57.

RESULTS

Twenty-two patients received vandetanib (n = 10, 100 mg; n = 12, 300 mg). Baseline measurements of iAUC(60 )and K(trans )were reproducible, with low intrapatient coefficients of variation (11% and 24%, respectively). Estimates of mean % changes from baseline were -3.4% (100 mg) and -4.6% (300 mg) for iAUC(60), and -4.6% (100 mg) and -2.7% (300 mg) for K(trans); these changes were not significantly different between doses. The exploratory T2* measurement showed a significant increase at 300 mg versus 100 mg (P = 0.006). Both doses of vandetanib were generally well tolerated; common toxicities were fatigue, rash and diarrhea (majority CTC grade 1 or 2). The pharmacokinetic profile of vandetanib was similar to that observed previously. There were no RECIST-defined objective responses; five patients experienced stable disease >/=8 weeks.

CONCLUSION

In this study in patients with advanced colorectal cancer, vandetanib did not modulate gadolinium uptake in tumor vasculature and tissue measured by the DCE-MRI parameters iAUC(60 )and K(trans).

TRIAL REGISTRATION

NCT00496509 (ClinicalTrials.gov); D4200C00050 (AstraZeneca).

Phase I study of BAY 73–4506, an inhibitor of oncogenic and angiogenic kinases, in patients with advanced refractory colorectal carcinoma (CRC)

3560^

Background: BAY 73–4506 is a potent inhibitor of the receptor tyrosine kinases (VEGFR, KIT, RET, FGFR and PDGFR) and serine/threonine kinases (RAF and p38MAPK). In in-vivo models, BAY 73–4506 has demonstrated a broad spectrum of antitumor activity. Methods: This phase I study investigated the safety and pharmacokinetic (PK)/pharmacodynamic (PD) profiles of BAY 73–4506, given orally in repeating cycles of 21 days on/7 days off, in patients with refractory CRC. PK assessments were performed on days 1 and 21 of cycle 1. PD markers - including DCE-MRI and plasma levels of VEGF/soluble VEGFR-2 - were assessed at each cycle. Tumor response was evaluated per RECIST. Results: 38 patients with actively progressing CRC were treated with BAY 73–4506 at doses of 60 mg (n = 1), 120 mg (n = 4), 160 mg (n = 26), and 220 mg (n = 7) once daily. Median treatment duration was 56.5 days (range, 7–219 days). Drug-related adverse events (AEs) of all grades reported in >20% of patients were hand-foot skin reaction (HFSR) (61%; CTC 3–4, 32%), fatigue (45%; CTC 3, 11%), hoarseness (24%; CTC 3, 3%), mucositis (24%), diarrhea (24%; CTC 3, 3%), anorexia (24%), and hypertension (21%; CTC 3, 13%). Treatment-related AEs leading to dose reduction, interruption, or discontinuation (in ≥2 of patients) were HFSR (26%), fatigue (18%), thrombopenia (8%), and hypertension (5%). BAY 73–4506 showed a dose-dependent increase in exposure up to 160 mg, at which point a plateau was reached. One of 27 evaluable patients achieved a partial response (4%), 15 had stable disease (SD) at least 7 weeks after the start of treatment (55%), and 6 had SD for more than 23 weeks (22%). Patients had extensive previous antitumor treatment, including bevacizumab (44%) and cetuximab (59%). Decreases in soluble VEGFR-2 levels and iAUC60s of Gd-DTPA by DCE-MRI demonstrated that BAY 73–4506 was active on biologically relevant markers. Conclusions: BAY 73–4506 dosing at 160 mg daily, using a treatment schedule of 21 days on/7 days off was feasible in patients with advanced refractory CRC. Promising clinical activity was shown, with a disease control rate (PR+SD) of 59% in evaluable patients. Mutational analysis of selected genes (KRAS, BRAF) is ongoing.

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ASCO Conflict of Interest Policy and Exceptions

In compliance with the guidelines established by the ASCO Conflict of Interest Policy (J Clin Oncol. 2006 Jan 20;24[3]:519–521) and the Accreditation Council for Continuing Medical Education (ACCME), ASCO strives to promote balance, independence, objectivity, and scientific rigor through disclosure of financial and other interests, and identification and management of potential conflicts. According to the ASCO Conflict of Interest Policy, the following financial and other relationships must be disclosed: employment or leadership position, consultant or advisory role, stock ownership, honoraria, research funding, expert testimony, and other remuneration (J Clin Oncol. 2006 Jan 20;24[3]:520). The ASCO Conflict of Interest Policy disclosure requirements apply to all authors who submit abstracts to the Annual Meeting.

For clinical trials that began accrual on or after April 29, 2004, ASCO's Policy places some restrictions on the financial relationships of principal investigators (J Clin Oncol. 2006 Jan 20;24[3]:521). If a principal investigator holds any restricted relationships, his or her abstract will be ineligible for placement in the 2009 Annual Meeting unless the ASCO Ethics Committee grants an exception. Among the circumstances that might justify an exception are that the principal investigator (1) is a widely acknowledged expert in a particular therapeutic area; (2) is the inventor of a unique technology or treatment being evaluated in the clinical trial; or (3) is involved in international clinical oncology research and has acted consistently with recognized international standards of ethics in the conduct of clinical research. NIH-sponsored trials are exempt from the Policy restrictions. Abstracts for which authors requested and have been granted an exception in accordance with ASCO's Policy are designated with a caret symbol (^) in the Annual Meeting Proceedings.

For more information about the ASCO Conflict of Interest Policy and the exceptions process, please visit www.asco.org/conflictofinterest .

Sauerstoff-MRT der Lunge: Optimierte Berechnung von Differenzbildern

BACKGROUND

In oxygen-enhanced lung MRI, difference maps of acquisitions during inhalation of room air and pure oxygen are calculated to assess lung function. The purpose of this study was to analyze how the calculation of these difference maps depends on the delayed signal change after switching the gas supply.

METHODS

Ten healthy volunteers were examined with an ECG and respiratory-triggered T1-weighting inversion recovery HASTE sequence with parallel imaging. Four blocks with 20 repetitions of up to 6 coronal slices were continuously acquired; in blocks 1 and 3 room air was supplied, in blocks 2 and 4 oxygen. Data were postprocessed, discarding between 0 and 19 repetitions after each change of gas supply before calculating the relative signal difference.

RESULTS

The averaged relative signal difference increases from 9.4 to 17.4% when the number of discarded acquisitions increases; the ratio of signal difference and spatial standard deviation reaches a maximum at 5-8 discarded acquisitions.

CONCLUSIONS

An optimized ratio of signal difference and statistical error is found if about 5-8 of 20 respiratory-triggered repetitions are discarded after each change of gas supply for the calculation of difference maps.

Fast oxygen-enhanced multislice imaging of the lung using parallel acquisition techniques

The purpose of this study was to evaluate an optimized multislice acquisition technique for oxygen-enhanced MRI of the lung using slice-selective inversion and refocusing pulses in combination with parallel imaging. An inversion recovery HASTE sequence was implemented with respiratory triggering to perform imaging in end-expiration and with ECG triggering to avoid image acquisition during the systolic phase. Inversion pulses and the readout of echo trains could be interleaved to decrease acquisition time. The sequence was evaluated in 15 healthy volunteers, comparing three acquisition schemes: (1) acquisition of four slices without parallel imaging; (2) acquisition of four slices with parallel imaging; (3) acquisition of six slices with parallel imaging. These multislice acquisitions were repeated 80 times with alternating inhalation of room air and oxygen. The oxygen-induced signal increase showed no significant difference with and without parallel imaging. However, only with parallel imaging did the interleaved acquisition of six or more slices become possible, thus enabling a more complete anatomic coverage of the lung. The average required end-expiration time per repetition to acquire six slices could be significantly reduced from 4112 ms without to 2727 ms with parallel imaging. Total acquisition time varied between 8 and 13 min depending on the respiratory frequency.