Final results from the large sunitinib global expanded-access trial in metastatic renal cell carcinoma.

BACKGROUND: We report final results with extended follow-up from a global, expanded-access trial that pre-regulatory approval provided sunitinib to metastatic renal cell carcinoma (mRCC) patients, ineligible for registration-directed trials. METHODS: Patients ⩾18 years received oral sunitinib 50 mg per day on a 4-weeks-on-2-weeks-off schedule. Safety was assessed regularly. Tumour measurements were scheduled per local practice. RESULTS: A total of 4543 patients received sunitinib. Median treatment duration and follow-up were 7.5 and 13.6 months. Objective response rate was 16% (95% confidence interval (CI): 15-17). Median progression-free survival (PFS) and overall survival (OS) were 9.4 months (95% CI: 8.8-10.0) and 18.7 months (95% CI: 17.5-19.5). Median PFS in subgroups of interest: aged ⩾65 years (33%), 10.1 months; Eastern Cooperative Oncology Group performance status ⩾2 (14%), 3.5 months; non-clear cell histology (12%), 6.0 months; and brain metastases (7%), 5.3 months. OS was strongly associated with the International Metastatic Renal-Cell Carcinoma Database Consortium prognostic model (n=4065). The most common grade 3/4 treatment-related adverse events were thrombocytopenia (10%), fatigue (9%), and asthenia, neutropenia, and hand-foot syndrome (each 7%). CONCLUSION: Final analysis of the sunitinib expanded-access trial provided a good opportunity to evaluate the long-term side effects of a tyrosine kinase inhibitor used worldwide in mRCC. Efficacy and safety findings were consistent with previous results.

Galectin-1 has potential prognostic significance and is implicated in clear cell renal cell carcinoma progression through the HIF/mTOR signaling axis.

BACKGROUND: Metastatic clear cell renal cell carcinoma (ccRCC) patients have <9% 5-year survival rate, do not respond well to targeted therapy and eventually develop resistance. A better understanding of molecular pathways of RCC metastasis is the basis for the discovery of novel prognostic markers and targeted therapies. METHODS: We investigated the biological impact of galectin-1 (Gal-1) in RCC cell lines by migration and invasion assays. Effect of Gal-1 expression on the mitogen-activated protein kinase pathway was assessed by proteome array. RESULTS: Increased expression of Gal-1 increased cell migration while knocking down Gal-1 expression by siRNA resulted in reduced cellular migration (P<0.001) and invasion (P<0.05). Gal-1 overexpression increased phosphorylation of Akt, mTOR and p70 kinase. Upon hypoxia and increased HIF-1α, Gal-1 increased in a dose-dependent manner. We also found miR-22 overexpression resulted in decreased Gal-1 and HIF-1α. Immunohistochemistry analysis showed that high Gal-1 protein expression was associated with larger size tumor (P=0.034), grades III/IV tumors (P<0.001) and shorter disease-free survival (P=0.0013). Using the Cancer Genome Atlas data set, we found that high Gal-1 mRNA expression was associated with shorter overall survival (41 vs 78 months; P<0.01). CONCLUSIONS: Our data suggest Gal-1 mediates migration and invasion through the HIF-1α-mTOR signaling axis and is a potential prognostic marker and therapeutic target.

First-, second-, third-line therapy for mRCC: benchmarks for trial design from the IMDC.

BACKGROUND: Limited data exist on outcomes for metastatic renal cell carcinoma (mRCC) patients treated with multiple lines of therapy. Benchmarks for survival are required for patient counselling and clinical trial design. METHODS: Outcomes of mRCC patients from the International mRCC Database Consortium database treated with 1, 2, or 3+ lines of targeted therapy (TT) were compared by proportional hazards regression. Overall survival (OS) and progression-free survival (PFS) were calculated using different population inclusion criteria. RESULTS: In total, 2705 patients were treated with TT of which 57% received only first-line TT, 27% received two lines of TT, and 16% received 3+ lines of TT. Overall survival of patients who received 1, 2, or 3+ lines of TT were 14.9, 21.0, and 39.2 months, respectively, from first-line TT (P<0.0001). On multivariable analysis, 2 lines and 3+ lines of therapy were each associated with better OS (HR=0.738 and 0.626, P<0.0001). Survival outcomes for the subgroups were as follows: for all patients, OS 20.9 months and PFS 7.2 months; for those similar to eligible patients in the first-line ADAPT trial, OS 14.7 months and PFS 5.6 months; for those similar to patients in first-line TIVO-1 trial, OS 24.8 months and PFS 8.2 months; for those similar to patients in second-line INTORSECT trial, OS 13.0 months and PFS 3.9 months; and for those similar to patients in the third-line GOLD trial, OS 18.0 months and PFS 4.4 months. CONCLUSIONS: Patients who are able to receive more lines of TT live longer. Survival benchmarks provide context and perspective when interpreting and designing clinical trials.

Outcomes of patients with metastatic renal cell carcinoma that do not meet eligibility criteria for clinical trials.

BACKGROUND: Targeted therapies in metastatic renal cell carcinoma (mRCC) have been approved based on registration clinical trials that have strict eligibility criteria. The clinical outcomes of patients treated with targeted agents but are ineligible for trials are unknown. PATIENTS AND METHODS: mRCC patients treated with vascular endothelial growth factor-targeted therapy were retrospectively deemed ineligible for clinical trials (according to commonly used inclusion/exclusion criteria) if they had a Karnofsky performance status (KPS) <70%, nonclear-cell histology, brain metastases, hemoglobin ≤9 g/dl, creatinine >2× the upper limit of normal, corrected calcium ≥12 mg/dl, platelet count of <100 × 10(3)/uL, or neutrophil count <1500/mm(3). RESULTS: Overall, 768 of 2210 (35%) patients in the International Metastatic RCC Database Consortium (IMDC) were deemed ineligible for clinical trials by the above criteria. Between ineligible versus eligible patients, the response rate, median progression-free survival (PFS) and median overall survival of first-line targeted therapy were 22% versus 29% (P = 0.0005), 5.2 versus 8.6 months, and 12.5 versus 28.4 months (both P < 0.0001), respectively. Second-line PFS (if applicable) was 2.8 months in the trial ineligible versus 4.3 months in the trial eligible patients (P = 0.0039). When adjusted by the IMDC prognostic categories, the HR for death between trial ineligible and trial eligible patients was 1.55 (95% confidence interval 1.378-1.751, P < 0.0001). CONCLUSIONS: The number of patients that are ineligible for clinical trials is substantial and their outcomes are inferior. Specific trials addressing the unmet needs of protocol ineligible patients are warranted.

miR-192, miR-194 and miR-215: a convergent microRNA network suppressing tumor progression in renal cell carcinoma.

MicroRNAs (miRNAs) play a crucial role in tumor progression and metastasis. We, and others, recently identified a number of miRNAs that are dysregulated in metastatic renal cell carcinoma compared with primary renal cell carcinoma. Here, we investigated three miRNAs that are significantly downregulated in metastatic tumors: miR-192, miR-194 and miR-215. Gain-of-function analyses showed that restoration of their expression decreases cell migration and invasion in renal cell carcinoma cell line models, whereas knockdown of these miRNAs resulted in enhancing cellular migration and invasion abilities. We identified three targets of these miRNAs with potential role in tumor aggressiveness: murine double minute 2, thymidylate synthase, and Smad Interacting protein 1/zinc finger E-box binding homeobox 2. We observed a convergent effect (the same molecule can be targeted by all three miRNAs) and a divergent effect (the same miRNA can control multiple targets) for these miRNAs. We experimentally validated these miRNA-target interactions using three independent approaches. First, we observed that miRNA overexpression significantly reduces the mRNA and protein levels of their targets. In the second, we observed significant reduction of the luciferase signal of a vector containing the 3'UTR of the target upon miRNA overexpression. Finally, we show the presence of inverse correlation between miRNA changes and the expression levels of their targets in patient specimens. We also examined the prognostic significance of miR-215 in renal cell carcinoma. Lower expression of miR-215 is associated with significantly reduced disease-free survival time. These findings were validated on an independent data set from The Cancer Genome Atlas. These results can pave the way to the clinical use of miRNAs as prognostic markers and therapeutic targets.

Primary anti-vascular endothelial growth factor (VEGF)-refractory metastatic renal cell carcinoma: clinical characteristics, risk factors, and subsequent therapy.

BACKGROUND: A subset of patients treated with initial anti-vascular endothelial growth factor (VEGF) therapy exhibit progressive disease (PD) as the best response per RECIST criteria. METHODS: Data from patients with metastatic renal cell carcinoma (mRCC) treated with anti-VEGF therapy were collected through the International mRCC Database Consortium from 12 centers. RESULTS: One thousand and fifty-six assessable patients received initial VEGF inhibitors and 272 (26%) of these patients had PD as best response. Initial treatment included sunitinib (n = 203), sorafenib (n = 51), or bevacizumab (n = 18). Six percent of patients were at favorable risk, 55% at intermediate risk, and 39% at poor risk. On multivariable analysis, predictors of PD were Karnofsky performance status < 80% [odds ratio (OR) = 2.3, P < 0.0001], diagnosis to treatment < 1 year (OR = 2.1, P < 0.0001), neutrophilia (OR = 1.9, P = 0.0021), thrombocytosis (OR = 1.7, P = 0.0068), and anemia (OR = 1.6, P = 0.0058). Median progression-free survival (PFS) in patients with PD versus without PD was 2.4 versus 11 months (P < 0.0001) and overall survival (OS) was 6.8 versus 29 months (P < 0.0001), respectively. One hundred and eight (40%) VEGF-refractory patients proceeded to receive further systemic therapies. Response rate, PFS, and OS for subsequent therapy were 9%, 2.5 months, and 7.4 months, respectively, with no statistical differences between patients who received VEGF versus mammalian target of rapamycin (mTOR) inhibitors. CONCLUSIONS: Primary anti-VEGF-refractory mRCC patients have a dismal prognosis. Second-line anti-mTOR and anti-VEGF agents produce similar outcomes.

Sex moderates circadian chemotherapy effects on survival of patients with metastatic colorectal cancer: a meta-analysis.

BACKGROUND: Molecular circadian clocks can modify cancer chemotherapy effects, with a possible moderation according to sex differences. We investigated whether sex determine the optimal delivery schedule of chemotherapy for metastatic colorectal cancer. PATIENTS AND METHODS: A meta-analysis was performed using individual data from three international Phase III trials comparing 5-fluorouracil, leucovorin and oxaliplatin administered in chronomodulated (chronoFLO) or conventional (CONV) infusions. The data from 345 females and 497 males were updated at 9 years. The main end point was survival. RESULTS: Overall survival was improved in males on chronoFLO when compared with CONV (P = 0.009), with respective median values of 20.8 (95% CL, 18.7 to 22.9) and 17.5 months (16.1 to 18.8). Conversely, median survival was 16.6 months (13.9 to 19.3) on chronoFLO and 18.4 months (16.6 to 20.2) on CONV in females (P = 0.012). The sex versus schedule interaction was a strong predictive factor of optimal treatment schedule, with a hazard ratio of 1.59 (1.30 to 1.75) for overall survival (P = 0.002) in multivariate analysis. CONCLUSIONS: Males lived significantly longer on chronomodulated chemotherapy rather than on conventional chemotherapy. The current chronoFLO schedule deserves prospective assessment as a safe and more effective first-line treatment option than conventional delivery for male patients.

miRNA profiling in metastatic renal cell carcinoma reveals a tumour-suppressor effect for miR-215.

BACKGROUND: Renal cell carcinoma (RCC) is the most common neoplasm of the adult kidney. Metastatic RCC is difficult to treat. The 5-year survival rate for metastatic RCC is ≤10%. Recently, microRNAs (miRNAs) have been shown to have a role in cancer metastasis and potential as prognostic biomarkers in cancer. METHOD: We performed a miRNA microarray to identify a miRNA signature characteristic of metastatic compared with primary RCCs. We validated our results by quantitative real-time PCR. We performed experimental and bioinformatic analyses to explore the involvement of miR-215 in RCC progression and metastasis. RESULTS: We identified 65 miRNAs that were significantly altered in metastatic compared with primary RCCs. We validated our results by examining the expression of miR-10b, miR-126, miR-196a, miR-204 and miR-215, in two independent cohorts of patients. We showed that overexpression of miR-215 decreased cellular migration and invasion in an RCC cell line model. In addition, through gene expression profiling, we identified direct and indirect targets of miR-215 that can contribute to tumour metastasis. CONCLUSION: Our analysis showed that miRNAs are altered in metastatic RCCs and can contribute to kidney cancer metastasis through different biological processes. Dysregulated miRNAs represent potential prognostic biomarkers and may have therapeutic applications in kidney cancer.

Real-world outcomes of nivolumab and cabozantinib in metastatic renal cell carcinoma: results from the International Metastatic Renal Cell Carcinoma Database Consortium.

Objectives: In the present study, we explored the real-world efficacy of the immuno-oncology checkpoint inhibitor nivolumab and the tyrosine kinase inhibitor cabozantinib in the second-line setting. Methods: Using the International Metastatic Renal Cell Carcinoma Database Consortium (imdc) dataset, a retrospective analysis of patients with metastatic renal cell carcinoma (mrcc) treated with nivolumab or cabozantinib in the second line after prior therapy targeted to the vascular endothelial growth factor receptor (vegfr) was performed. Baseline characteristics and imdc risk factors were collected. Overall survival (os) and time to treatment failure (ttf) were calculated using Kaplan-Meier curves. Overall response rates (orrs) were determined for each therapy. Multivariable Cox regression analysis was performed to determine survival differences between cabozantinib and nivolumab treatment. Results: The analysis included 225 patients treated with nivolumab and 53 treated with cabozantinib. No significant difference in median os was observed: 22.10 months [95% confidence interval (ci): 17.18 months to not reached] with nivolumab and 23.70 months (95% ci: 15.52 months to not reached) with cabozantinib (p = 0.61). The ttf was also similar at 6.90 months (95% ci: 4.60 months to 9.20 months) with nivolumab and 7.39 months (95% ci: 5.52 months to 12.85 months) with cabozantinib (p = 0.20). The adjusted hazard ratio (hr) for nivolumab compared with cabozantinib was 1.30 (95% ci: 0.73 to 2.3), p = 0.38. When adjusted by imdc criteria and age, the hr was 1.32 (95% ci: 0.74 to 2.38), p = 0.35. Conclusions: Real-world imdc data indicate comparable os and ttf for nivolumab and cabozantinib. Both agents are reasonable therapeutic options for patients progressing after initial first-line vegfr-targeted therapy.

Cost-utility of Sunitinib Versus Pazopanib in Metastatic Renal Cell Carcinoma in Canada using Real-world Evidence.

BACKGROUND AND OBJECTIVE: The development of new targeted therapies in kidney cancer has shaped disease management in the metastatic phase. Our study aims to conduct a cost-utility analysis of sunitinib versus pazopanib in first-line setting in Canada for metastatic renal cell carcinoma (mRCC) patients using real-world data. METHODS: A Markov model with Monte-Carlo microsimulations was developed to estimate the clinical and economic outcomes of patients treated in first-line with sunitinib versus pazopanib. Transition probabilities were estimated using observational data from a Canadian database where real-life clinical practice was captured. The costs of therapies, disease progression, and management of adverse events were included in the model in Canadian dollars ($Can). Utility and disutility values were included for each health state. Incremental cost-utility ratio (ICUR) and incremental cost-effectiveness ratios (ICER) were calculated for a time horizon of 5 years, from the Canadian Healthcare System perspective. RESULTS: The cost difference was $36,303 and the difference in quality-adjusted life year (QALY) was 0.54 in favour of sunitinib with an ICUR of $67,227/QALY for sunitinib versus pazopanib. The major cost component (56%) is related to best supportive care (BSC) where patients tend to stay for a longer period of time compared to other states. The difference in life years gained (LYG) between sunitinib and pazopanib was 1.21 LYG (33.51 vs 19.03 months) and the ICER was $30,002/LYG. Sensitivity analysis demonstrated the robustness of the model with a high probability of sunitinib being a cost-effective option when compared to pazopanib. CONCLUSION: When using real-world evidence, sunitinib is found to be a cost-effective treatment compared to pazopanib in mRCC patients in Canada.

Does the Time of Radiotherapy Affect Treatment Outcomes? A Review of the Literature.

Circadian rhythm-dependent cell cycle progression produces daily variations in radiosensitivity. This literature review aims to summarise the data on whether radiotherapy outcomes differ depending on administration time. A literature search was conducted on Ovid Medline, Embase, Cochrane Central Register of Controlled Trials and PubMed using key words such as 'radiotherapy', 'circadian rhythm', 'treatment outcome' and 'survival'. Articles evaluating the correlation between radiotherapy time and outcomes in cancer patients were included and relevant information was extracted. Nine studies met the inclusion criteria. Four investigated lung cancer patients undergoing stereotactic radiosurgery for brain metastases, with one study observing improved local control and survival in patients treated in the morning. Another two studies with breast and cervical cancer patients observed that the prevalence of toxicities was higher in afternoon and morning cohorts, respectively. Two studies in head and neck cancer patients found trends indicating morning patients experienced less oral mucositis. Increased toxicities and biochemical failure rates were associated with evening treatment in prostate cancer patients. As inconsistencies in the literature exist regarding the time dependency of radiotherapy outcomes, further investigation is warranted.

Circadian cancer therapy.

PURPOSE AND DESIGN: To review briefly the growing body of published data about circadian variation in cytotoxic drug metabolism and tissue sensitivity to chemotherapeutic agents. The suggestion that toxicity may be reduced and anticancer efficacy improved by administering antineoplastic agents at carefully selected times of the day was assessed. RESULTS AND CONCLUSION: The medical literature describing molecular, cellular, and organismic time-keeping mechanisms, as well as circadian rhythms, in cytokinetic, pharmacokinetic, and pharmacodynamic parameters relevant to cancer chemotherapy, which support the predictable rhythmic relationship between dose and effect that occurs during each day, were reviewed. Advantages for optimal circadian scheduling have been demonstrated for diminishing side effects and increasing maximal safe dose-intensity of drugs of diverse class. The use of the predictable circadian relationship of dose and response provides another increment of progress in the treatment of cancer patients.

Phase II study of troxacitabine (BCH-4556) in patients with advanced and/or metastatic renal cell carcinoma: a trial of the National Cancer Institute of Canada-Clinical Trials Group.

PURPOSE: A multi-institution phase II study was undertaken by National Cancer Institute of Canada-Clinical Trials Group to evaluate the efficacy and toxicity of intravenous troxacitabine (Troxatyl; Shire Pharmaceuticals Plc, Laval, Quebec, Canada), in patients with renal cell carcinoma. PATIENTS AND METHODS: Between June 1999 and March 2000, 35 patients (24 male) with a mean age of 60 years who had advanced and/or metastatic disease were treated with troxacitabine given as an intravenous infusion over 30 minutes at a dose of 10 mg/m2 intravenously, once every 3 weeks. RESULTS: Of the 33 of 35 patients evaluable for response, there were two confirmed partial responses, 21 patients had stable disease (median duration, 4.4 months), and 10 patients had progressive disease. Eight patients remained stable for more than 6 months, of whom six remain free of progression. The most common drug-related nonhematologic toxicities observed were skin rash (77.1%), hand-foot syndrome (68.6%), alopecia (51.4%), fatigue (51.4%), and nausea (57.1%). Out of a total of 145 cycles of treatment, 98 were given without steroid premedication, whereas 47 cycles were given with steroid premedication. Without premedication, skin rash occurred in 37% of cycles compared with 26% when steroids were given prophylactically. CONCLUSION: Troxacitabine given at a dose of 10 mg/m2 once every 3 weeks was well tolerated in patients with metastatic renal cell cancer, with common toxicities being a moderate to severe granulocytopenia and skin rash. Steroid premedication may reduce the frequency and severity of the skin rash. Our current study suggests that the nucleoside analog troxacitabine may have modest activity against renal cell carcinoma; however, larger studies are required to confirm this.

Phase I study of 5-fluorouracil and leucovorin by a 14-day circadian infusion in metastatic adenocarcinoma patients.

Initial experimental and clinical studies have indicated that 5-fluorouracil (5-FU) toxicity can be reduced by delivering 5-FU at around 4 a.m. More recent data have suggested that the toxicity might be reduced even more with delivery at around 9-10 p.m. The current study determined the maximum tolerated dose (MTD) for 5-FU and leucovorin (LV) delivered as a continuous circadian infusion over 14 days every 28 days, with the peak of the infusion occurring at around 3-4 a.m. The peak drug delivery was shifted to 9-10 p.m. in all patients developing toxicity of > or = grade II (Eastern Cooperative Oncology Group) to determine if this timing further reduced toxicity and enabled increased dose intensity. A total of 14 patients with metastatic adenocarcinoma received an admixture of 5-FU and LV via a programmable portable infusion pump, with 62.5% of the 24-h dose being given over 7 h around the infusion peak. The starting dose level of 5-FU (200 mg/m2 daily) and LV (5 mg/m2 daily) was that established as the highest tolerable dose rate in a previously reported phase I study using a 14-day flat infusion of 5-FU and LV. The LV dose was first escalated to 20 mg/m2 daily, followed by escalations of the 5-FU dose. A total of 51 courses were evaluable for toxicity. The dose-limiting toxicity was oral mucositis and hand-foot syndrome. More dose intensity could be delivered using a circadian infusion peaking at around 3-4 a.m. than was possible with a flat infusion of these drugs. Toxicity was reduced even further with peak drug delivery at around 9-10 p.m. The recommended dose for phase II studies using this schedule is 250 mg/m2 5-FU daily and 20 mg/m2 LV daily with the peak of the infusion occurring at 9-10 p.m. This is a 300% and 25% higher dose for LV and 5-FU, respectively, than was found to be safe for a flat infusion.

Phase I-II study of 5-fluorouracil, leucovorin, doxorubicin, methotrexate, and long-term oral etoposide (FLAME) in unresectable or metastatic gastric cancer.

The objective of this phase I-II study was to determine the efficacy and toxicity of combination chemotherapy with 5-fluorouracil, leucovorin, doxorubicin, methotrexate, and oral etoposide (FLAME) in patients with measurable unresectable or metastatic gastric cancer. Starting doses on the phase I study were as follows: methotrexate 50 mg/m2 intravenous bolus day 1; leucovorin 20 mg/m2 intravenous bolus days 2 through 4, starting 24 hours after the methotrexate dose; 5-fluorouracil 325 mg/m2 intravenous bolus 15 minutes after leucovorin days 2 through 4; doxorubicin 25 mg/m2 intravenous bolus day 8; and oral etoposide 50 mg/day for 14 days, starting on day 8. A new cycle started on day 28. A total of 42 patients were treated--10 patients in the phase I study and 32 patients in the phase II study. Dose-limiting toxicity was encountered in the phase I study on the second escalation step, when doxorubicin was escalated to 30 mg/m2 and 5-fluorouracil was escalated to 350 mg/m2. In the phase II study 28 patients (109 courses) were evaluable for toxicity. Neutropenia grade 3 or more was dose limiting and was documented in 12 patients (43%) during 22 treatment courses (20%). Neutropenia was associated with febrile neutropenia requiring hospitalization in four patients during five courses of therapy. Grade 3 stomatitis and grade 3 diarrhea was infrequent, documented in two patients (two courses) and three patients (four courses), respectively. All other toxicity was grade 1 and grade 2. The combined objective response rate in 38 evaluable patients entered in both studies was 23.3% (six partial responses and one complete response). Stable disease was documented in 15 patients (39.5%). The median survival for the 42 patients entered in both trials was 6.9 months (95% confidence interval, 5.9-8.5 months). The objective response rate and median survival for the combined group is comparable with that reported for the etoposide, leucovorin, and 5-fluorouracil (ELF), and 5-fluorouracil and methotrexate (FMTX) regimens in a recently reported, multicenter, phase III study.

Clinical chronotolerance to anticancer drugs: relevance for dose-intensity.

There is increasing experimental and clinical data to suggest that the timing of chemotherapy may be important for both toxicity and response. The availability of programmable infusion pumps has made the clinical testing and application of circadian scheduling possible. This paper provides an overview regarding the current clinical data with some references to the experimental studies. Further progress in this area is dependent on a better understanding of the mechanisms involved and continued high quality clinical trials.

Progression-free survival as a clinical trial endpoint in advanced renal cell carcinoma.

Traditionally, overall survival (os) has been considered the "gold standard" for evaluating new systemic oncologic therapies, because death is easy to define, is easily compared across disease sites, and is not subject to investigator bias. However, as the available options for continuing therapy increase, the use of os as a clinical trial endpoint has become problematic because of the increasing crossover and contamination of trials. As a result, the approval of promising new therapies may be delayed.Many clinicians believe that progression-free survival (pfs) is a more viable option for evaluating new therapies in metastatic and advanced renal cell carcinoma. As with all endpoints, pfs has inherent biases, and those biases must be addressed to ensure that trial results are not compromised and that they will be accepted by regulatory authorities. In this paper, we examine the issues surrounding the use of pfs as a clinical trial endpoint, and we suggest solutions to ensure that data integrity is maintained.

Chronobiology. Implications for cancer chemotherapy.

Experimental studies have documented that both the toxicity and the antitumor activity of many cancer drugs are time dependent. Early clinical trials have confirmed this observation for several drugs. The basic concepts of chronobiology and its application to pharmacology are reviewed. As an example, clinical trials of circadian fluoropyrimidine delivery are reviewed. Other clinical results are presented in table form. The mechanisms pertinent to the circadian time dependence of fluoropyrimidines are discussed.