Cabazitaxel versus abiraterone or enzalutamide in poor prognosis metastatic castration-resistant prostate cancer: a multicentre, randomised, open-label, phase II trial

BACKGROUND

Treatment of poor prognosis metastatic castration-resistant prostate cancer (mCRPC) includes taxane chemotherapy and androgen receptor pathway inhibitors (ARPI). We sought to determine optimal treatment in this setting.

PATIENTS AND METHODS

This multicentre, randomised, open-label, phase II trial recruited patients with ARPI-naive mCRPC and poor prognosis features (presence of liver metastases, progression to mCRPC after <12 months of androgen deprivation therapy, or ≥4 of 6 clinical criteria). Patients were randomly assigned 1 : 1 to receive cabazitaxel plus prednisone (group A) or physician's choice of enzalutamide or abiraterone plus prednisone (group B) at standard doses. Patients could cross over at progression. The primary endpoint was clinical benefit rate for first-line treatment (defined as prostate-specific antigen response ≥50%, radiographic response, or stable disease ≥12 weeks).

RESULTS

Ninety-five patients were accrued (median follow-up 21.9 months). First-line clinical benefit rate was greater in group A versus group B (80% versus 62%, P = 0.039). Overall survival was not different between groups A and B (median 37.0 versus 15.5 months, hazard ratio (HR) = 0.58, P = 0.073) nor was time to progression (median 5.3 versus 2.8 months, HR = 0.87, P = 0.52). The most common first-line treatment-related grade ≥3 adverse events were neutropenia (cabazitaxel 32% versus ARPI 0%), diarrhoea (9% versus 0%), infection (9% versus 0%), and fatigue (7% versus 5%). Baseline circulating tumour DNA (ctDNA) fraction above the cohort median and on-treatment ctDNA increase were associated with shorter time to progression (HR = 2.38, P < 0.001; HR = 4.03, P < 0.001). Patients with >30% ctDNA fraction at baseline had markedly shorter overall survival than those with undetectable ctDNA (HR = 38.22, P < 0.001).

CONCLUSIONS

Cabazitaxel was associated with a higher clinical benefit rate in patients with ARPI-naive poor prognosis mCRPC. ctDNA abundance was prognostic independent of clinical features, and holds promise as a stratification biomarker.

A Canadian cancer trials group phase IB study of durvalumab (anti-PD-L1) plus tremelimumab (anti-CTLA-4) given concurrently or sequentially in patients with advanced, incurable solid malignancies

Background The IND.226 study was a phase Ib study to determine the recommended phase II dose of durvalumab + tremelimumab in combination with standard platinum-doublet chemotherapy. Sequential administration of multiple agents increases total chair time adding costs overall and inconvenience for patients. This cohort of the IND.226 study evaluated the safety and tolerability of durvalumab + tremelimumab given either sequentially (SEQ) or concurrently (CON). Methods Patients with advanced solid tumours were enrolled and randomised to either SEQ tremelimumab 75 mg IV over 1 h followed by durvalumab 1500 mg IV over 1 h q4wks on the same day, or CON administration over 1 h. The serum pharmacokinetic profile of SEQ versus CON of durvalumab and tremelimumab administration was also evaluated. Results 14 patients either received SEQ (n = 7pts) or CON (n = 7 pts). There were no infusion related reactions. Drug related adverse events (AEs) were mainly low grade and manageable, and comparable in frequency between SEQ/CON- fatigue (43%/57%), rash (43%/43%), pruritus (43%/29%) and nausea (14%/29%). One patient in each cohort discontinued treatment due to toxicity. The PK profiles of durvalumab and tremelimumab were similar between CON and SEQ, and to historical reference data. Conclusions Concurrent administration of durvalumab and tremelimumab over 1 h is safe with a comparable PK profile to sequential administration.

OCTANE (Ontario-wide Cancer Targeted Nucleic Acid Evaluation): a platform for intraprovincial, national, and international clinical data-sharing

Cancer is a genetic disease resulting from germline or somatic genetic aberrations. Rapid progress in the field of genomics in recent years is allowing for increased characterization and understanding of the various forms of the disease. The Ontario-wide Cancer Targeted Nucleic Acid Evaluation (octane) clinical trial, open at cancer centres across Ontario, aims to increase access to genomic sequencing of tumours and to facilitate the collection of clinical data related to enrolled patients and their clinical outcomes. The study is designed to assess the clinical utility of next-generation sequencing (ngs) in cancer patient care, including enhancement of treatment options available to patients. A core aim of the study is to encourage collaboration between cancer hospitals within Ontario while also increasing international collaboration in terms of sharing the newly generated data. The single-payer provincial health care system in Ontario provides a unique opportunity to develop a province-wide registry of ngs testing and a repository of genomically characterized, clinically annotated samples. It also provides an important opportunity to use province-wide real-world data to evaluate outcomes and the cost of ngs for patients with advanced cancer. The octane study is attempting to translate knowledge to help deliver precision oncology in a Canadian environment. In this article, we discuss the background to the study and its implementation, current status, and future directions.

Bone Health and Bone-targeted Therapies for Prostate Cancer: a Programme in Evidence-based Care - Cancer Care Ontario Clinical Practice Guideline

AIMS

To make recommendations with respect to bone health and bone-targeted therapies in men with prostate cancer.

MATERIALS AND METHODS

A systematic review was carried out by searching MEDLINE, EMBASE and the Cochrane Library from inception to January 2016. Systematic reviews and randomised-controlled trials were considered for inclusion if they involved therapies directed at improving bone health or outcomes such as skeletal-related events, pain and quality of life in patients with prostate cancer either with or without metastases to bone. Therapies included medications, supplements or lifestyle modifications alone or in combination and were compared with placebo, no treatment or other agents. Disease-targeted agents such as androgen receptor-targeted and chemotherapeutic agents were excluded. Recommendations were reviewed by internal and external review groups.

RESULTS

In men with prostate cancer receiving androgen deprivation therapy, baseline bone mineral density testing is encouraged. Denosumab should be considered for reducing the risk of fracture in men on androgen deprivation therapy with an increased fracture risk. Bisphosphonates were effective in improving bone mineral density, but the effect on fracture was inconclusive. No medication is recommended to prevent the development of first bone metastasis. Denosumab and zoledronic acid are recommended for preventing or delaying skeletal-related events in men with metastatic castration-resistant prostate cancer. Radium-223 is recommended for reducing symptomatic skeletal events and prolonging survival in men with symptomatic metastatic castration-resistant prostate cancer.

CONCLUSIONS

The recommendations represent a current standard of care that is feasible to implement, with outcomes valued by clinicians and patients.

A phase I dose-escalation study of apatorsen (OGX-427), an antisense inhibitor targeting heat shock protein 27 (Hsp27), in patients with castration-resistant prostate cancer and other advanced cancers

BACKGROUND

Heat shock protein 27 (Hsp27) is a chaperone protein that regulates cell survival via androgen receptor and other signaling pathways, thereby mediating cancer progression. Apatorsen (OGX-427) is a 2'-methoxyethyl-modified antisense oligonucleotide that inhibits Hsp27 expression. This study evaluated the safety profile and recommended phase II dosing of apatorsen in patients with advanced cancer.

PATIENTS AND METHODS

Patients with castration-resistant prostate (CRPC), breast, ovary, lung, or bladder cancer were enrolled to this phase I dose-escalation study. Apatorsen was administered i.v. weekly in 21-day cycles following 3 loading doses and over 5 dose levels (200-1000 mg). Apatorsen plasma concentrations, circulating tumor cells (CTCs) and CTC Hsp27 expression, and serum Hsp27 levels were evaluated.

RESULTS

Forty-two patients were accrued, of which 52% had CRPC. Patients were heavily pretreated, with 57% having had ≥3 prior chemotherapy regimens. During the loading dose/cycle 1 and overall study period, 93% and 100% of patients (N = 42) experienced treatment-related adverse events, respectively; most were grade 1-2 and included chills, pruritus, flushing, prolonged aPTT, lymphopenia, and anemia. One patient experienced a dose-limiting toxicity at the 600 mg dose level (intracranial hemorrhage in a previously undiagnosed brain metastasis). A maximum tolerated dose was not defined. Apatorsen Cmax increased proportionally with dose. Decreases in tumor markers and declines in CTCs were observed, with a prostate-specific antigen decline >%50% occurring in 10% of patients with CRPC; 29/39 assessable patients (74%) had reductions from ≥5 CTC/7.5 ml at baseline to <5 CTC/7.5 ml post-treatment. Twelve patients had stable measurable disease as best response.

CONCLUSIONS

Apatorsen was tolerated at the highest dose evaluated (1000 mg). Single-agent activity was suggested by changes in tumor markers, CTC, and stable measurable disease. Phase II studies evaluating apatorsen are underway.

CLINICALTRIALSGOV ID

NCT00487786.

A phase I study of the combination of ro4929097 and cediranib in patients with advanced solid tumours (PJC-004/NCI 8503)

Background:

The Notch signalling pathway has been implicated in tumour initiation, progression, angiogenesis and development of resistance to vascular endothelial growth factor (VEGF) targeting, providing a rationale for the combination of RO4929097, a γ-secretase inhibitor, and cediranib, a VEGF receptor tyrosine kinase inhibitor.

Methods:

Patients received escalating doses of RO4929097 (on a 3 days-on and 4 days-off schedule) in combination with cediranib (once daily). Cycle 1 was 42 days long with RO4929097 given alone for the first 3 weeks followed by the co-administration of both RO4929097 and cediranib starting from day 22. Cycle 2 and onwards were 21 days long. Soluble markers of angiogenesis were measured in plasma samples. Archival tumour specimens were assessed for expression of three different components of Notch signalling pathway and genotyping.

Results:

In total, 20 patients were treated in three dose levels (DLs). The recommended phase II dose was defined as 20 mg for RO4929097 on 3 days-on and 4 days-off schedule and 30 mg daily for cediranib. The most frequent treatment-related adverse events (AEs) were diarrhoea, hypertension, fatigue and nausea. Eleven patients had a best response of stable disease and one patient achieved partial response. We did not detect any correlation between tested biomarkers of angiogenesis or the Notch pathway and treatment effect. There was no correlation between mutational status and time to treatment failure.

Conclusion:

RO4929097 in combination with cediranib is generally well tolerated at the DLs tested. Preliminary evidence of antitumour efficacy with prolonged disease stabilisation in some patients with progressive malignancies warrants further clinical investigation of this treatment strategy.

Systemic therapy in men with metastatic castration-resistant prostate cancer: a systematic review

AIMS

Since 2004, docetaxel-based chemotherapy has been the standard of care for men with metastatic castration-resistant prostate cancer (mCRPC), but recently randomised controlled trials (RCTs) of novel agents have shown promise in extending overall survival. These trials have evaluated agents delivered before chemotherapy, to replace or supplement docetaxel, or addressed treatment options for men who have progressed on docetaxel therapy. This review was undertaken to determine which systemic therapies improve cancer- or patient-related outcomes in men with mCRPC.

MATERIALS AND METHODS

Searches were carried out in MEDLINE, EMBASE, the Cochrane Library and relevant conference proceedings. Eligible articles included RCTs comparing systemic therapy or combination (excluding primary or secondary androgen deprivation therapy, bone protective agents or radionuclides) with placebo or other agents in men with mCRPC.

RESULTS

Twenty-five RCTs met the selection criteria. In chemotherapy-naive patients, targeted therapy with tasquinimod conferred a benefit in progression-free survival. Immunotherapy with sipuleucel-T extended overall survival and was well tolerated, but had no effect on the time to disease progression. Hypercastration with abiraterone extended progression-free survival, whereas overall survival was improved but not statistically proven. In the chemotherapy setting, updated and new trials of docetaxel alone confirmed the survival benefit seen in previous studies. A survival benefit with the addition of estramustine to docetaxel shown in a previous study did not lead to an improvement in pain palliation or quality of life. Trials of combining targeted therapies with docetaxel generally did not extend survival. The addition of bevacizumab improved progression-free survival, but not overall survival. The addition of GVAX immunotherapy or calcitriol was harmful. In the post-chemotherapy setting, progression-free and overall survival benefits were detected with cabazitaxel, abiraterone and enzalutamide. Cabazitaxel was associated with greater toxicity, whereas abiraterone and enzalutamide had less severe adverse effects. Satraplatin and sunitinib both extended progression-free survival, but did not improve overall survival.

CONCLUSION

Docetaxel-based chemotherapy remains the standard of care in men with mCRPC who are candidates for palliative systemic therapy. Promising results are emerging with sipuleucel-T and abiraterone in the pre-docetaxel setting and cabazitaxel, abiraterone and enzalutamide in patients who progress on or after docetaxel. Further research to determine the optimal choice, sequence or even the combination of these agents is necessary.

A phase II trial of dacomitinib, an oral pan-human EGF receptor (HER) inhibitor, as first-line treatment in recurrent and/or metastatic squamous-cell carcinoma of the head and neck

BACKGROUND

An open-label, multicenter, single-arm phase II trial was conducted to investigate the clinical activity of dacomitinib in recurrent/metastatic squamous-cell carcinoma of the head and neck (RM-SCCHN).

PATIENTS AND METHODS

Eligible patients were administered dacomitinib at 45 mg orally daily, in 21-day cycles. Primary end point was objective response rate.

RESULTS

Sixty-nine patients were enrolled with a median age of 62 years. Among response-evaluable patients, 8 [12.7%, 95% confidence interval (CI) 5.6% to 23.5%] achieved a partial response and 36 (57.1%) had stable disease, lasting ≥24 weeks in 9 patients (14.3%). The median progression-free survival (PFS) was 12.1 weeks and the median overall survival (OS) was 34.6 weeks. Most adverse events (AEs) were tolerable. The most common grade 3 or higher treatment-related AEs were diarrhea (15.9%), acneiform dermatitis (8.7%), and fatigue (8.7%). Treatment-related AEs led to at least one dose interruption in 28 (40.6%) patients and dose reductions in 26 (37.7%). Permanent treatment discontinuation occurred in 8 (11.6%) patients due to treatment-related AEs.

CONCLUSIONS

Dacomitinib demonstrated clinical activity in RM-SCCHN, and the primary end point of this study was met. The toxicity profile of this agent was generally manageable with dose interruptions and adjustments.

A phase 2 study of patupilone in patients with metastatic castration-resistant prostate cancer previously treated with docetaxel: Canadian Urologic Oncology Group study P07a

BACKGROUND

The purpose of this study was to determine the clinical activity of patupilone in patients with metastatic castration-resistant prostate cancer previously treated with docetaxel.

PATIENTS AND METHODS

Eligible patients had progressive disease within 6 months of receiving docetaxel. Patupilone was administered 10 mg/m2 i.v. every 3 weeks. The primary end point was the proportion of patients with a confirmed≥50% prostate-specific antigen (PSA) decline.

RESULTS

Eighty-three patients were enrolled. At baseline, the median time to progression after prior docetaxel was 1.4 months (range 0-5.7). Gastrointestinal serious adverse events occurred in four of the six initial patients leading to a reduction of the starting dose of patupilone to 8 mg/m2 for subsequent patients. Grade 3-4 toxicity at this dose included diarrhea (22%), fatigue (21%), and anorexia (10%). One patient experienced grade 3-4 hematologic toxicity. A PSA decline of ≥50% occurred in 47% of patients. A partial measurable disease response occurred in 24% of assessable patients. A patient-reported pain response was observed in 59% of assessable patients. Median time to PSA progression was 6.1 months [95% confidence interval (CI) 4.7-8.0] and median overall survival was 11.3 months (95% CI 9.8-15.4).

CONCLUSIONS

Patupilone at 8 mg/m2 was tolerable, had antitumor activity, and was associated with symptomatic improvement in patients previously treated with docetaxel.

A phase II study of sunitinib in recurrent and/or metastatic adenoid cystic carcinoma (ACC) of the salivary glands: current progress and challenges in evaluating molecularly targeted agents in ACC

BACKGROUND

Vascular endothelial growth factor (VEGF) and c-kit are highly expressed in adenoid cystic carcinoma (ACC) and associated with biologic aggressiveness. This study aimed to assess the antitumor activity of sunitinib, a multi-targeted inhibitor of vascular endothelial growth factor receptor, c-kit, platelet-derived growth factor receptor, ret proto-oncogene (RET) and FMS-like tyrosine kinase 3 (FLT3), in ACC of the salivary gland.

PATIENTS AND METHODS

Patients with progressive, recurrent and/or metastatic ACC were treated with sunitinib 37.5 mg daily in this single-arm, two-stage phase II trial. Response was assessed every 8 weeks.

RESULTS

Fourteen patients were enrolled on to the study. Among 13 assessable patients, there were no objective responses, 11 patients had stable disease (SD), 8 patients had SD ≥ 6 months and 2 patients had progressive disease as best response. Median time to progression was 7.2 months. Median overall survival was 18.7 months. Toxic effects occurring in at least 50% of patients included fatigue, oral mucositis and hypophosphatemia usually of mild to moderate severity.

CONCLUSIONS

Although no responses were observed, sunitinib was well tolerated, with prolonged tumor stabilization of ≥ 6 months in 62% of assessable patients. The lack of responses is comparable with other trials of molecularly targeted agents in ACC and highlights the need for novel strategies in phase II clinical trial design.

Prophylactic feeding tubes for patients with locally advanced head-and-neck cancer undergoing combined chemotherapy and radiotherapy-systematic review and recommendations for clinical practice

GOALS

This work aimed to determine the benefits and risks of prophylactic feeding tubes for adult patients with squamous cell carcinoma of the head and neck who receive combined chemotherapy and radiotherapy with curative intent and to make recommendations on the use of prophylactic feeding tubes and the provision of adequate nutrition to this patient population.

METHODS

A national multidisciplinary panel conducted a systematic review of the evidence and formulated recommendations to guide clinical decision-making. The draft evidence summary and recommendations were distributed to clinicians across Canada for their input.

MAIN RESULTS

No randomized controlled trials have directly addressed this question. Evidence from studies in the target population was limited to seven descriptive studies: two with control groups (one prospective, one retrospective) and five without control groups. Results from ten controlled studies in patients treated with radiotherapy alone were also reviewed.

CONCLUSIONS

The available evidence was insufficient to draw definitive conclusions about the effectiveness of prophylactic feeding tubes in the target patient population or to support an evidence-based practice guideline. After review of the evidence, of guidelines from other groups, and of current clinical practice in Canada, the multidisciplinary panel made consensus-based recommendations regarding comprehensive interdisciplinary clinical care before, during, and after cancer treatment. The recommendations are based on the expert opinion of the panel members and on their understanding of best clinical practice.

Current management of castrate-resistant prostate cancer

Prostate cancer (PCa) is the most frequently diagnosed cancer in North America. Castrate-resistant PCa presents a spectrum of disease ranging from rising PSA levels in the absence of metastases or symptoms and despite androgen-deprivation therapy, to metastases and significant debilitation from cancer symptoms. Castrate-resistant PCa is usually suspected in patients with new symptoms on androgen deprivation therapy, with a rising PSA, or with new evidence of disease on bone scans or computed tomography scans. Institution of treatment and the choice of systemic or local therapy depend on a number of factors. This review discusses the various currently available treatments for patients with castrate-resistant PCa, from secondary hormonal manipulations to options for post-docetaxel systemic therapy.

Neoadjuvant temsirolimus in high-risk renal cell carcinoma: Results from a single-center prospective study

387

Background: The current first-line treatment for advanced renal cell carcinoma (RCC) includes targeted therapy with or without cytoreductive radical nephrectomy. There is a paucity of data as to the effectiveness of adjuvant and neoadjuvant treatment before radical nephrectomy for localized high-risk or advanced disease. We initiated a trial of neoadjuvant Temsirolimus before radical nephrectomy for locally advanced and metastatic RCC examining tumor response and survival.

Methods: Patients who presented with advanced RCC were offered enrolment into a prospective, single-centre, ethics approved trial with 12 weeks of temsirolimus before radical nephrectomy. Biopsy tissue was obtained at enrollment and at time of cytoreductive nephrectomy for diagnosis. Patients were administered 25 mg in temsirolimus on a weekly basis for 12 weeks, and then underwent radical nephrectomy. Computed tomography scans and biomarkers were obtained on enrolment, 6 weeks and 12 weeks (before nephrectomy). Ongoing outcome and survival data were analyzed.

Results: Eight patients were enrolled into the trial. Patient #1 (10-cm renal mass with bulky adenopathy T2N2M0) had no evidence of disease (NED) at 6 months post-nephrectomy. Patient #2 (9-cm renal mass, bulky adenopathy, pulmonary metastases T2N2M1) also had NED at 6 months postnephrectomy. Patients #3 and #4 experienced regression of the primary mass and have recently undergone uneventful surgery with follow-up pending. Patients #5 and #6 expired prior to the full course of therapy, but had diagnoses other than RCC. Patient #7 experienced disease progression, however, this patient's nephrectomy was delayed by 3 months due to an unrelated myocardial infarct. Patient #8 experienced adverse events.

Conclusions: Our findings suggest that neoadjuvant temsirolimus before radical nephrectomy for advanced RCC may improve disease regression post-surgery, and may lead to disease resolution in patients with low-volume disease. Randomized studies with longer term follow-up is necessary to assess overall progression-free survival and overall survival.

[Table: see text]

Mature results of a randomized phase II study of OGX-011 in combination with docetaxel/prednisone versus docetaxel/prednisone in patients with metastatic castration-resistant prostate cancer

5012

Background: Clusterin is a cytoprotective chaperone protein associated with CRPC progression. OGX is a 2'-methoxyethyl antisense that potentiates chemotherapy in xenografts and inhibits clusterin expression at doses of <640 mg. Methods: Pts with CRPC and chemo-naive received docetaxel (DOC) 75mg/m2 q3w + OGX 640mg IV weekly + prednisone (Arm A) or DOC + prednisone (Arm B) in a single stage randomized phase II design. Primary endpoint was PSA response rate (RR). Progression-free survival (PFS) and overall survival (OS) were secondary endpoints. Planned sample size was 40/arm: Arm A the hypotheses (PSA RR<40% vs. >60%) could be tested at 10% β and 10% α, Arm B the true PSA RR could be estimated with half-width of the 90% CI<13% if PSA RR=40%. Results: 82 pts (41 Arm A, 41 Arm B) were randomized from 09/05–12/06. At this analysis time, all pts are off therapy and 49 have died. One pt was ineligible but included in ITT survival analysis. Baseline characteristics were similar: median age 69 (49–87), PSA >100 μg/L in 51%, Hgb ≥100 g/L in 98%, alk phos >ULN in 44%, LDH >ULN in 36%, ECOG performance status (PS) 0:1 in 51%:49%, bone/lymph node/visceral metastases in 69%/50%/28%. Median cycles for Arm A and B was 9 and 7. Adverse events associated with OGX included fatigue, fever, rigors, diarrhea and rash. Mean serum clusterin change on day 1 cycle 2 was -18% in Arm A and +8% in Arm B (p = 0.0005). PSA RR was 58% (Arm A) and 54% (Arm B). PSA declines at 12 weeks of any/>30%/>50% was observed in 87%/65%/45% (Arm A) and 68%/58%/34% (Arm B). PSA/objective disease progression as best response occurred in 0%/4% (Arm A), and 3%/17% (Arm B). PFS for Arms A and B was 7.3 (5.3–8.8) and 6.1 months (3.7–8.6). Median OS for Arms A and B was 27.5 (19.2-∞) and 16.9 months (12.7–26.0) (unadjusted HR = 0.60 [0.34–1.06], p = 0.07). Variables predictive of OS on multivariate analysis: PS 0 vs 1 (p = 0.0002), presence of visceral metastasis (p = 0.006) and treatment assignment (HR = 0.54 [0.29–0.97], p = 0.04). Conclusions: The PSA RR in both arms met criterion for further study. OGX reduced serum clusterin and OS appears superior with DOC/OGX. This combination warrants further evaluation. Supported by a grant from the NCI-Canada/Canadian Cancer Society.

[Table: see text]

OGX-427, a 2'methoxyethyl antisense oligonucleotide (ASO), against HSP27: Results of a first-in-human trial

3506

Background: Heat shock protein 27 (Hsp27) is a chaperone protein expressed in many cancers and implicated as a therapeutic “hyper-node” affecting multiple pathways in cancer progression. Overexpression of Hsp27 confers a resistant phenotype. OGX-427 is a second generation ASO that inhibits Hsp27 expression which in preclinical models inhibited cell growth, induced apoptosis, and enhanced chemotherapy efficacy. The purpose of this phase 1 study was to determine the recommended phase 2 dose of OGX-427 alone and in combination with docetaxel. Methods: Eligible patients (pts) had to have metastatic breast, ovarian, prostate, NSCLC, or bladder cancer. OGX-427 was administered IV weekly on a 21-day cycle after 3 loading doses (LD) within 9 days. OGX-427 was escalated over 5 planned dose levels (DL) (200, 400, 600, 800, 1,000 mg), with 6 pts/DL. Plasma PK and serial ECGs were performed in cycle 1. Circulating tumor cells (CTC), Hsp27+ CTC and serum Hsp27 levels were evaluated serially. Results: 34 pts have been accrued and single agent dose escalation is complete. Median age was 62 (range: 33–86) yrs; 16 pts had prostate, 10 breast, 5 ovary and 3 lung ca. Median cycles administered were 2 (0–8) with 2 pts remaining on treatment. Most common related AEs: chills (53%), pruritis (29%), flushing (21%), elevated creatinine (18%), fatigue (15%), arthralgia (15%). More than 80% of pts had grade (Gr) 1/2 infusion reactions during the LDs or C1. One pt on 1,000 mg DL was hospitalized with Gr 3 infusion reaction. Gr 3 elevations of PTT (with normal INR) were seen in >50% of pts on 800 and 1,000 mg DL. At 600 mg DL, one pt had a Gr 3 epistaxis and one pt had a DLT with a Gr 3 cerebral bleed into a metastasis. No significant QTcF changes were observed. Three pts with prostate ca had PSA declines of 43%, 58%, 62% and 3 pts with ovarian cancer had CA-125 declines of 27%, 28%, and 41%. Five pts have had stable disease for >3 months. Preliminary mean PK data for 200–600 mg DLs: T1/2 = 2.8–3.1 hrs, peak concentration = 21,756 - 102,591 ng/mL and AUCinf ranged from 63,552 - 328,153 ng.h/mL, increasing with dose. Declines in CTC and Hsp27+ CTC have been observed at all DL. Conclusions: OGX-427 was well tolerated. Toxicity consisted mainly of infusion reactions and transient PTT changes. Changes in tumor markers suggest single-agent activity.

[Table: see text]

Effect of geographic distance from a cancer centre on choice of systemic therapy in metastatic colorectal cancer

e17559

Background: There is little data on whether geographic distance from patient residence to a treatment facility is a predictor of systemic therapy utilization or clinical trial (CT) enrollment. Therefore a retrospective chart review was undertaken to investigate this variable. Methods: Consecutive patients with metastatic colorectal cancer (mCRC) assessed by a medical oncologist at the Juravinski Cancer Centre (JCC), Ontario during 2006 were selected. Patients with pathology other than adenocarcinoma and those with complete surgical resection of metastases were excluded. Distance and time to JCC were calculated using online mapping software. The study received full ethics approval. Results: 276 patients were included with full data available on 169 patients. Median travel time and distance to JCC were 23.0 minutes (min) and 19.2 kilometers (km), respectively. The maximum travel time was 120 min and 87% of patients lived within 60 min of JCC. Distance and time were highly correlated (p<0.0001). Overall, 43% of patients had discussed a CT with their oncologist and 20% enrolled in a CT. Patients living >50 km from JCC were less likely to discuss a CT (38%) or participate in a CT (15%) than patients who lived 25–50 km (39% and 19%) or <25 km (47% and 23%) from JCC. These trends did not attain statistical significance (odds ratio [OR] = 0.88, 95% CI = 0.66–1.17, p = 0.39 for CT discussion, OR = 0.76, 95% CI = 0.54–1.08, p = 0.13 for CT enrollment). Distance was not a statistically significant (p = 0.42) predictor of number of treatment regimens, however, 44% of patients <25 km from JCC received 3 or more lines of treatment compared with 33% of patients ≥25 km away. No association with survival was observed. Conclusions: Patients with mCRC living ≥25 km from JCC received fewer systemic regimens and were less likely to discuss or enter a CT. These trends were not statistically significant. Data collection is ongoing to increase the power of this study.

No significant financial relationships to disclose.

Cost-effectiveness of cetuximab for the first-line treatment of squamous cell carcinoma of the head and neck (SCCHN) in Canada

e17000

Background: Squamous cell carcinoma of the head and neck (SCCHN) is a disfiguring and potentially fatal condition. Cetuximab is a new therapeutic option which has been shown to improve locoregional control (LRC) and reduce mortality in the treatment of locally and regionally advanced disease. Objectives: To estimate the incremental cost-utility of cetuximab plus radiotherapy (CxRT) versus cisplatin plus radiotherapy (CsRT) among platinum eligible patients and versus RT alone in platinum ineligible patients in Canada. Methods: A lifetime transition model was developed with four health states: 1) acute treatment phase; 2) LRC; 3) disease progression and 4) death. Adverse events were accounted for in the first two states. Efficacy of treatment (LRC and overall survival) was obtained from the literature. Based on network meta-analyses, CsRT and CxRT were assumed to have equal efficacy. Resource use was obtained from published literature and clinical expert opinion. The perspective adopted was that of a provincial ministry of health or cancer agency. Utilities were obtained from a previous study of United Kingdom oncology nurses. Costs (2008 CDN$) and outcomes were discounted at 5% annually. Incremental cost-effectiveness ratios (ICERs) were reported with one-way and probabilistic sensitivity analyses performed to assess robustness of results. A priori sub-group analyses were carried out by baseline Karnofsky Performance Scores (KPS). Results: Among all patients (KPS 60–100), the ICERs comparing CxRT to RT were $19,740/QALY (95% CI: $11,122 to $695,295) among platinum ineligible patients and for CxRT vs. CsRT, $99,147/QALY (95% CI: $75,998 to $148,951) among platinum eligible patients. ICERs decreased with increasing KPS scores. At a willingness to pay of $50,000 among platinum-ineligible patients and $100,000 among platinum-eligible patients, the likelihood that CxRT is cost-effective is 90% and 45% respectively. Sensitivity analyses indicated that time horizon and assumptions about CsRT effectiveness had the largest impact on results. Conclusion: Cetuximab is an economically attractive option for SCCHN patients.

[Table: see text]

A phase II study of sorafenib in patients with chemo-naive castration-resistant prostate cancer

BACKGROUND

The purpose of this trial was to evaluate the antitumor activity of sorafenib, a multikinase inhibitor of cell proliferation and angiogenesis, in patients with castration-resistant prostate cancer.

PATIENTS AND METHODS

This was a multicenter, two-stage, phase II study. Sorafenib 400 mg was administered orally twice daily continuously. Primary end point was prostate-specific antigen (PSA) 'response' defined as a > or =50% decrease for > or =4 weeks.

RESULTS

In all, 28 patients were enrolled. Eastern Cooperative Oncology Group performance status was zero or one in 19 and 9 patients. Two patients had no metastases, and 26 had bone and/or lymph node disease. A median of two cycles (range 1-8) was delivered. Adverse events were typical for sorafenib. The PSA response rate was 3.6% [95% confidence interval (CI) 0.1% to 18.3%] with response occurring in one patient (baseline = 10 000 and nadir = 1643 microg/l). No measurable disease responses occurred in eight patients. Time to PSA progression was 2.3 months (95% CI 1.8-6.4). Of 16 patients who discontinued sorafenib and then did not receive any immediate therapy, 10 had postdiscontinuation PSA declines of 7%-52%.

CONCLUSIONS

Sorafenib has limited activity using current PSA criteria. The declines in PSA observed on treatment discontinuation indicate an effect on PSA production/secretion. Further study may be warranted but needs to consider the limitations of PSA as an indicator of progression and response.

A randomized phase II study of OGX-011 in combination with docetaxel and prednisone or docetaxel and prednisone alone in patients with metastatic hormone refractory prostate cancer (HRPC)

5069

Background: Clusterin, a cytoprotective chaperone protein that promotes cell survival, is associated with androgen independent progression and overexpressed in HRPC. OGX-011 (OGX, developed by OncoGenex Technologies/Isis Pharmaceuticals) is a 2’- methoxyethyl modified phosphorothioate antisense that inhibits clusterin expression in humans at doses of ≤640 mg and potentiates chemotherapy activity in prostate xenografts. The objective of this study was to determine the anti-tumor activity of OGX in combination with docetaxel (DOC) in patients (pts) with HRPC. Methods: Chemo-naive pts with metastatic HRPC were randomized to receive DOC 75mg/m2 q3 weeks + OGX 640mg weekly as a 2-hour IV infusion (Arm A) + prednisone or DOC + prednisone (Arm B). Serum levels of clusterin were assessed serially. A single stage randomized phase II design was employed with PSA response rate (RR) as the primary endpoint (Bubley et al, J Clin Oncol 1999;17:3461). Planned sample size was 40 per arm: Arm A the hypotheses (H0:PSA RR<40% vs. H1:PSA RR>60%) could be tested at 10% β and 10% a, Arm B the true PSA RR could be estimated with half-width of the 90% confidence interval <13% if observed PSA RR was 40%. Results: 82 pts (41/arm) were enrolled from September 2005 to December 2006 at 12 centers. Baseline characteristics are similar in both arms (available to date for 63 pts): median age 67 (range: 49–84), PSA 110 μg/L (5.6–1261), hemoglobin 128 g/L (96–158), alkaline phosphatase 133 U/L (47–1294), LDH 193 U/L (120–741). ECOG performance status was 0 in 49% and 1 in 51%; 67% had bone/nodal disease only and 33% had other metastatic sites. To date, 56 pts have received ≥2 cycles. Toxicity due to OGX included grade 1/2 fevers and rigors in 37% and 67% pts respectively, but other adverse events were similar in both arms. PSA response has occurred in 43%, progression in 9%, and 48% have not yet met criteria for response or progression. Conclusions: Combined docetaxel and OGX is well tolerated in pts with metastatic HRPC and PSA responses have been observed. Pt treatment, follow-up and analysis of serum clusterin levels continue. Results by arm will be available by June 2007. Supported by a grant from the NCI-Canada/Canadian Cancer Society.

No significant financial relationships to disclose.

Phase II study of the angiogenesis inhibitor AZD2171 in first line, progressive, unresectable, advanced metastatic renal cell carcinoma (RCC): A trial of the PMH Phase II Consortium

5093

Background: AZD2171 is an oral, highly potent inhibitor of VEGFR1, VEGFR2, with activity also against cKit, PDGFRβ and Flt-4. We conducted a two-stage, phase II trial of AZD 2171 in first line advanced RCC, with a planned sample size of 37 pts, and a primary endpoint of tumor control rate (PR+SD). Methods: Pts had progressive, unresectable, advanced RCC, measurable disease, a performance status of ≤ 2 and no prior cytokine or antiangiogenic therapy. Pts received AZD2171 45 mg orally, daily, continuously (1cycle = 4wks) as monotherapy. Disease was evaluated with cross-sectional imaging every 8 wks. Functional DCE-MRI imaging was performed at baseline, 24h and 28d after the first dose. Pharmacokinetic studies were performed on day 8, 15 and 28. Results: From January- November 2006, 24 pts median (range) age 62 (44–80), were entered on study. Sixteen pts evaluable for response, 7 too early; 23 pts evaluable for toxicity; 1 pt inevaluable due to withdrawal. There have been 6 confirmed PR (6/16=38%), 1 unconfirmed PR, 5 SD, 4 PD. Tumor control rate 12/16=75%. Seventeen patients remain on treatment, 6 now off due to PD and 1 off due to consent withdrawal. Eighteen patients had dose reductions due to toxicity. Most common toxicities (any grade) were fatigue (21pts), voice alteration (14pts), hypertension (12pts), diarrhea (15pts), and increased creatinine (10pts). Common (>5% of cycles) grade 3+ adverse events were hypertension (5pts), joint pain (4pts), fatigue (7pts), dyspnea (2pts), increased ALT (2pts) and anorexia (3pts). Preliminary pK analysis is available on 6 patients: median (range) Tmax: 2hr (2- 6hr), Cmax: 107.8± 29.8 ng/ml, T1/2: 12.1 ± 2.2hr. Conclusion: AZD2171 is an active agent in first line, progressive, unresectable, advanced RCC with a partial response rate of 38% and tumor control rates of 75%. Accrual is ongoing with pharmacokinetics, functional imaging, and correlative studies. This agent warrants further investigation.

No significant financial relationships to disclose.

Quality and consistency of phase III clinical trial abstracts presented at an Annual Meeting of the American Society of Clinical Oncology compared with their subsequent full-text publications

6537

Background: Practice guidelines and evidence summaries in oncology are developed by experts to assist providers in making appropriate decisions regarding management. These documents result from a systematic review of literature from medical journals and meeting proceedings. Because there is often less rigorous peer reviewing of abstracts published in these proceedings compared to journal publications, the quality of evidence provided by these abstracts is uncertain. Methods: We identified abstracts describing phase III clinical trials of chemotherapy, chemoradiotherapy, immune therapy and hormone therapy presented at the 36th ASCO Annual Meeting in May 2000. We searched Medline and Pubmed for all corresponding publications. Data was extracted from the abstracts and publications meeting our inclusion criteria. Results: A total of 192 abstracts were identified. Seventy-four abstracts met our inclusion criteria. Six years after the 2000 ASCO Annual Meeting, 74% of these abstracts had corresponding publications. 39% of the abstracts explicitly indicated that they were reporting interim results. The primary endpoint was stated in 34% of the abstracts and 100% of the published papers. The primary outcome result differed by greater than five percent between the abstract and publication in 25% of the abstracts. The statistical significance of the primary outcome changed in 7% of the abstracts with publications. The final conclusion was consistent between the abstract and publication for 92% of the abstracts with reported conclusions. Conclusions: ASCO annual meeting abstracts of phase III trials appear to consistently reflect final published results and can likely be used in practice guidelines. However, occasional discrepancies underline the need for caution in completely adopting these results prior to full publication.

No significant financial relationships to disclose.

The Advanced Renal Cell Carcinoma Sorafenib (ARCCS) expanded access trial: Subset analysis of patients (pts) with brain metastases (BM)

15506

Background: Sorafenib (SOR) was demonstrated to be safe and effective in a phase III trial of previously treated RCC pts; however, pts with BM were excluded. BM occur in 5–10% of RCC pts, and generally portend a poor prognosis. Safety and efficacy of SOR in this pt population was therefore explored in a subset analysis of ARCCS, a community-based expanded access program. Methods: Pts received SOR 400 mg bid in this open-label, nonrandomized trial if they were =15 years old with advanced RCC and had ECOG PS of 0–2. Pts with BM were included but required to have some prior local therapy for their brain lesions. Prior treatment did not have to be successful, and pts whose BM had been surgically removed were also eligible for this protocol. BM were excluded as target lesions for RECIST unless they were the only lesions being followed. Major exclusion criteria included treatment with other investigational drugs within 4 wks of enrollment; life expectancy <2 mos; active coronary artery disease, ischemia, or hypertension; and severe renal impairment requiring dialysis. The primary endpoints were safety and efficacy (per investigator assessed RECIST criteria). Results: Of 2,488 ARCCS pts valid for safety, 65 (2.6%) had been previously treated for BM: 72.3% male with median age 59.5 yrs. 99% had =1 prior therapy for non-brain disease including 81.5 % radiotherapy, 78.5% nephrectomy and 47.7% prior systemic therapy. Grade 3 adverse events (AE) occurring >2% in this subset were fatigue and seizure (6.2% each) and hand-foot skin reaction, diarrhea, hemoglobin, mucositis, dehydration, vomiting, hyperglycemia, and thrombosis (3.1% each). In the total ARCCS population vs the BM subset, Grade 3 AEs were 35.2% vs 26.2% and Grade 4 AEs were 6.1% vs 9%. There were no CNS-related bleeding events in pts with BM. Of the 47 pts evaluable for response, partial response was reported in 2 (4%), stable disease in 33 (70%), and progressive disease in 12 (26%). Conclusions: The toxicity and efficacy of SOR in pts with brain mets in ARCCS were comparable to those observed in the whole study population. Of note, SOR was well tolerated in this study with no reports of cerebral hemorrhagic events.

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A phase II study of lapatinib in recurrent or metastatic EGFR and/or ErbB2 expressing adenoid cystic (ACC) and non-ACC malignant tumors of the salivary glands (MSGT)

5566

Background: The limited therapeutic index of chemotherapy in recurrent or metastatic MSGT provides a strong rationale for the evaluation of molecularly targeted agents in this disease. Lapatinib is a dual inhibitor of EGFR and ErbB2 tyrosine kinase activity. Expression of ErbB2 and EGFR has been associated with biological aggressiveness and poor prognosis in MSGT, respectively. We conducted a phase II study to determine the antitumor activity of lapatinib in MSGT. Methods: The main study has a two-stage design in which patients (pts) with progressive, recurrent or metastatic ACC, and immunohistochemically expressing at least 1+ EGFR and/or 2+ ErbB2, were treated with lapatinib 1500 mg PO daily. Each cycle consists of 4 weeks of continuous dosing. Pts with non-ACC MSGT of other histologies, meeting identical eligibility criteria, were treated in this trial as a single-stage, separate cohort. Results: Of 57 pts screened for this study, 29/33 (88%) ACC and 22/24 (92%) non-ACC pts expressed EGFR and/or ErbB2. Thirty-eight pts have been accrued to the study to date (20 ACC/18 non-ACC). The remaining 13 pts who were screened positive either declined entry or were ineligible for other reasons. Baseline data on 34 pts are: M:F = 25:9, median age 56 (range 38–80), PS 0:1:2 = 16:17:1, prior radiation:chemotherapy = 30:18. After 92 cycles of therapy, the most frequent adverse events experienced (as % of cycles) were diarrhea (54%), pain (52%), fatigue (52%), lymphopenia (39%), anemia (38%), hyperglycemia (38%) and dyspnea (34%). No grade 4 adverse events have occurred and only 8 pts experienced a grade 3 adverse event, primarily pain and dyspnea. No significant cardiac toxicity has been observed. Among 14 ACC pts evaluable for response so far: 9 have SD (range 2–9 cycles), 3 PD, and 2 died prior to cycle 2. For 12 evaluable non-ACC pts: 8 have SD (range 2–9 cycles), and 4 PD. No pts have had an objective response. Conclusions: Although there are no objective responses to date, lapatinib is well tolerated, with tumor stabilization achieved by 64% of pts and 24/38 pts remain on treatment at present. Trial accrual of ACC pts into the first stage has been completed, the second stage will open if an objective response is seen.

No significant financial relationships to disclose.

A phase II study of the antisense oligonucleotide GTI-2040 plus docetaxel and prednisone as first line treatment in hormone refractory prostate cancer (HRPC)

13015

Background: Despite initial responses to chemotherapy, median survival in HRPC remains a dismal 18 mos. Novel therapeutic approaches are clearly needed. The enzyme ribonucleotide reductase (RNR) composed of 2 subunits, R1 and R2 is essential for DNA synthesis and repair. The R2 subunit is often overexpressed in tumors increasing their malignant potential and promoting drug resistance. GTI-2040 (Lorus Therapeutics, Canada) is an antisense oligonucleotide to the R2 subunit downregulating its expression. In preclinical studies, GTI-2040 has shown antitumor activity in prostate cancer xenografts, synergy and non-overlapping toxicity with the taxanes. It is therefore a rational choice for combination with docetaxel in HRPC. Objectives: To determine efficacy of this regimen using PSA response rate. Secondary objectives include: duration of response, TTP, objective tumor response rate, safety and tolerability. Pharmacokinetic (PK) studies will be performed. PBMC will be used to determine RNR activity and R2 subunit quantitation. Methods: HRPC patients with PS 0–2, adequate organ function and no prior chemotherapy were treated with GTI-2040 5mg/kg/d continuous infusion for 14d, docetaxel 75 mg/m2 IV every 21d, and prednisone 5mg twice daily. Results: Twenty-two pts in 5 centers have been enrolled. Pts have received a total of 107 cycles to date. Median age 63 (52–77); median baseline PSA 140 (26–1256); ECOG 0:1:2: 14:7:1; prior radiotherapy in 14 pts. Pts received a median of 5 cycles (2–10). Grade 3/4 hematologic toxicities were lymphophenia (10pts), leukopenia (7pts), and neutropenia (7pts). Anemia (any grade) was seen in 19 pts across 92 cycles. Most frequent non-hematologic toxicities were fatigue and pain. PSA responses seen in 9/22 pts. Objective tumor response:1 PR, 9 SD, 3 PD, 3 off due to toxicity prior to objective response measurement, 3 no measureable lesions, 3 to be assessed. 19 pts off treatment: 9 PD, 4 toxicity (1 toxic death), 2 completed 10 cycles, 2 at investigator’s discretion and 2 withdrew consent. Three pts remain on study. Median TTP estimated at 17 wks. Accrual has been sufficient to meet stage 1 requirements. Final response, toxicity, pK, RNR and R2 subunit analysis will be available and presented.

No significant financial relationships to disclose.

Phase I trial of UCN-01 in combination with topotecan in patients with advanced solid cancers: a Princess Margaret Hospital Phase II Consortium study

BACKGROUND

7-Hydroxystaurosporine (UCN-01) inhibits serine-threonine kinases including the Ca2+ and phospholipid-dependent protein kinase C (PKC), CDKs 2, 4, 6, Chk-1 and PDK1. UCN-01 mediates distinct effects in vitro/in vivo: cell cycle arrest in G1, abrogation of G2 arrest by inhibiting chk1, induction of apoptosis and potentiation of cytotoxicity of S-phase-active chemotherapeutics including the topoisomerase 1 inhibitor topotecan (T). This phase I study was designed to determine the maximal tolerated dose (MTD), recommended phase 2 dose (RPTD), toxicity profile, pharmacokinetics and antitumor activity of T and UCN-01 in patients with refractory solid tumors.

DESIGN

Both agents were administered every 21 days intravenously through central venous access in escalating doses to eligible patients. On day 1, following antiemetic prophylaxis with dexamethasone and a serotonin type 3(A) receptor (5HT3) inhibitor, UCN-01 was infused over 3 h, followed by T infused over 30 min. On days 2-5, patients received T only. UCN-01 doses were reduced by 50% in cycles 2 and beyond because of its prolonged half-life.

RESULTS

Thirty-three patients were entered in three cohorts: Dose Level (DL) 1 (UCN-01 70 mg/m2, T 0.75 mg/m2), three patients; DL 2 (UCN-01 70 mg/m2, T 1.0 mg/m2), 24 patients; DL 3 (UCN-01 90 mg/m2, T 1.0 mg/m2), six patients. All but three patients were PS 0 or 1, median age was 54 years (range, 29-72), 91% were female. Primary tumor types: ovary/peritoneal (23 patients), colon (three patients), salivary gland (two patients), others (five patients). All patients were eligible for adverse event (AE) analysis and 22 patients were eligible for survival and tumor response analysis. Two of six patients had dose limiting toxicity (DLT) at DL 3 (grade 3 N/V; grade 4 neutropenia with infection). One DLT was seen in one patient at DL 2, consisting of grade 4 leukopenia. This cohort was expanded and no further DLTs were observed. Most common drug-related AEs were mild (grade 1-2). Non-hematological grade 3-4 AEs consisted of transient hyperglycemia (4), infection (3), coagulation, fatigue, hypotension, nausea (2), hypomagnesemia, vomiting, headache (1). Hematologic toxicities occurred in 100% of patients. Grade 3-4 hematologic abnormalities included neutropenia (16, including three with infection), leukopenia (11), lymphopenia (7), thrombocytopenia (5). Best response for 22 evaluable patients was PD (8), SD for at least six cycles (12), PR (1: carcinoma of ovary, dose level 2) and one not assessable. Pharmacokinetic analysis confirmed the prolonged half-life of UCN-01 of approximately 15 days.

CONCLUSIONS

DLT was observed at DL 3 and RPTD was determined to be DL 2. To date, this combination has been relatively well tolerated with some preliminary evidence of efficacy. A phase II study of this combination in patients with ovarian cancer is underway.

Phase I study to determine the safety and pharmacokinetics of the novel Raf kinase and VEGFR inhibitor BAY 43-9006, administered for 28 days on/7 days off in patients with advanced, refractory solid tumors

BACKGROUND

BAY 43--9006, an oral multi-kinase inhibitor, targets serine-threonine kinases and receptor tyrosine kinases, and affects the tumor and vasculature in preclinical models. Based on its pharmacologic effect, it may be a useful cancer treatment. This study determined the maximum tolerated dose (MTD) of BAY 43-9006 in 42 patients with advanced, refractory metastatic or recurrent solid tumors. Dose-limiting toxicities (DLTs), safety, pharmacokinetics and tumor response were also evaluated.

PATIENTS AND METHODS

In this open-label, phase I, dose-escalation study, BAY 43--9,006 was administered orally in repeated cycles of 35 days (28 days on/7 days off). Eight doses were investigated: from 50 mg every fourth day to 600 mg twice daily. Treatment continued until unacceptable toxicity, tumor progression or death.

RESULTS

The MTD was 400 mg twice daily. BAY 43-9006 was well tolerated, with mild to moderate toxicities; only six patients discontinued study therapy due to adverse events. DLTs consisted of hand-foot skin reaction in three of seven patients receiving 600 mg twice daily. Stable disease was achieved in 22% of patients; median duration of stable disease was 7.2 months. Consistent with its observed half-life of approximately 27 h, BAY 43-9, 006 accumulated on multiple dosing. Increases in exposure were less than proportional to the increases in dose.

CONCLUSIONS

Results indicate that further clinical investigation of BAY 43--9006 is warranted, and suggest it could be a promising future therapy for patients with cancer.