Results of a prospective phase 2 study of pazopanib in patients with surgically unresectable or metastatic chondrosarcoma.

BACKGROUND: This single-arm, multicenter, phase 2 study evaluated the safety and antitumor activity of pazopanib in patients with unresectable or metastatic conventional chondrosarcoma. METHODS: Eligible patients had conventional chondrosarcoma of any grade with measurable tumors that were unresectable or metastatic. Patients with mesenchymal, dedifferentiated, and extraskeletal myxoid chondrosarcoma subtypes and patients who received prior tyrosine kinase inhibitor therapy were excluded. Pazopanib at 800 mg once daily was administered for 28-day cycles. Tumor responses were evaluated by local radiology assessments every 2 cycles. The primary endpoint was the disease control rate (DCR) at week 16 (4 cycles). RESULTS: Forty-seven patients were enrolled. The DCR at 16 weeks was 43% (95% confidence interval [CI], 28%-58%), which was superior to the null hypothesis rate of 30%, but the 2-sided P value (exact test) was .09 (1-sided P = .045). One patient had a partial response. The median overall survival was 17.6 months (95% CI, 11.3-35.0 months), and the median progression-free survival was 7.9 months (95% CI, 3.7-12.6 months). Grade 3 or higher adverse events were infrequent; hypertension (26%) and elevated alanine aminotransferase (9%) were most common. CONCLUSIONS: This study provides evidence of positive drug activity for pazopanib in conventional chondrosarcoma.

First-in-human, phase I study of elisidepsin (PM02734) administered as a 30-min or as a 3-hour intravenous infusion every three weeks in patients with advanced solid tumors.

This first-in-human, phase I clinical trial was designed to determine the dose-limiting toxicities (DLTs) and the dose for phase II trials (P2D) of elisidepsin (PM02734) administered as a 30-min or as a 3-h intravenous infusion every 3 weeks (q3wk). Between March 2006 and April 2011, 53 patients with advanced malignant solid tumors were enrolled and treated with elisidepsin on the two different q3wk infusion schedules: 22 (30-min) and 31 (3-h), respectively. Doses evaluated ranged from 0.1 to 1.6 mg/m(2) (30-min q3wk) and from 2.0 to 11.0 mg flat dose (FD) (3-h q3wk). In the 30-min q3wk schedule, transient grade 3/4 increases in hepatic transaminases were the DLT, which appeared at the highest doses tested (from 1.1 to 1.6 mg/m(2)). No DLTs were observed on the 3-h schedule at doses up to 11.0 mg q3wk. Common adverse events were grade 1/2 pruritus, nausea, fatigue and hypersensitivity. Of note, myelotoxicity was not observed. Plasma maximum concentration and total drug exposure increased linearly with dose. Prolonged (≥3 months) disease stabilization was observed in pretreated patients with pleural mesothelioma (n = 1) in the 30-min q3wk arm, and with colorectal adenocarcinoma (n = 3), esophagus adenocarcinoma, endometrium adenocarcinoma, pleural mesothelioma, and head and neck carcinoma (n = 1 each) in the 3-h q3wk arm. In conclusion, elisidepsin doses of 1.1 mg/m(2) (equivalent to a FD of 2.0 mg) and 11.0 mg FD are the dose levels achieved for further phase II trials testing the 30-min q3wk and 3-h q3wk schedules, respectively.

A pharmacogenetic study of aldehyde oxidase I in patients treated with XK469.

XK469 (NSC 697887) is a selective topoisomerase II ß inhibitor eliminated mainly by aldehyde oxidase I (AOX1). We performed a candidate gene study to investigate whether AOX1 genetic variation contributes to interindividual variability in XK469 clearance. Forty-one AOX1 single nucleotide polymorphisms (SNPs) and seven liver expression quantitative trait loci were genotyped in White patients with advanced refractory solid tumors (n=59) and leukemia (n=33). We found a significant decrease in clearance (τ=-0.32, P=0.003) in solid tumor patients with rs10931910, although it failed to replicate in the leukemia cohort (τ=0.18, P=0.20). Four other AOX1 SNPs were associated with clearance (P=0.01-0.02) in only one of the two cohorts. Our study provides a starting point for future investigations on the functionality of AOX1 SNPs. However, variability in XK469 clearance cannot be attributed to polymorphisms in AOX1.

Pharmacokinetic variability of anticancer agents.

The translation of advances in cancer biology to drug discovery can be complicated by pharmacokinetic variation between individuals and within individuals, and this can result in unpredictable toxicity and variable antineoplastic effects. Previously unrecognized variables (such as genetic polymorphisms) are now known to have a significant impact on drug disposition. How can the pharmacokinetic variability of anticancer agents be reduced? This will require the understanding of correlations between pharmacokinetics and treatment outcomes, the identification of relevant patient parameters, mathematical modelling of individual and population pharmacokinetics, and the development of algorithms that will tailor doses to the individual patient.

Cixutumumab and temsirolimus for patients with bone and soft-tissue sarcoma: a multicentre, open-label, phase 2 trial.

BACKGROUND: Preclinical studies have shown synergistic antitumour activity by inhibition of insulin-like growth factor-1 receptor (IGF-1R) and mTOR. The expression of IGF-1R seems to be crucial for this effect. We investigated the safety and efficacy of the combination of the IGF-1R antibody cixutumumab and the mTOR inhibitor temsirolimus in patients with chemotherapy-refractory bone and soft-tissue sarcomas according to IGF-1R expression by immunohistochemistry. METHODS: We undertook a multicentre, open-label, phase 2 study in 19 cancer centres in the USA. Patients aged at least 16 years with a histologically confirmed diagnosis of bone or soft-tissue sarcoma were allocated on the basis of IGF-1R expression by immunohistochemistry to one of three treatment groups: IGF-1R-positive soft-tissue sarcoma (group A), IGF-1R-positive bone sarcomas (group B), or IGF-1R-negative bone and soft-tissue sarcoma (group C). Patients received weekly treatment with cixutumumab (6 mg/kg, intravenous) and temsirolimus (25 mg, intravenous flat dose) in 6-week cycles. A Simon optimal two-stage design was used for every arm. The primary endpoint was progression-free survival (PFS) at 12 weeks by intention-to-treat analysis in the first 54 patients assigned to every treatment arm. Although patients still remain on treatment, this trial has completed enrolment and this represents the final analysis. This study is registered with ClinicalTrials.gov, number NCT01016015. FINDINGS: Between Nov 18, 2009, and April 11, 2012, 388 patients were screened for IGF-1R expression and 54 were assigned to each arm. 17 of 54 patients in the IGF-1R-positive soft-tissue sarcoma group (31%; one-sided 95% CI lower bound 21%; two-sided 90% CI 21-43), 19 of 54 in IGF-1R-positive bone sarcoma group (35%; one-sided 95% CI lower bound 24%; two-sided 90% CI 24-47), and 21 of 54 in the IGF-1R-negative group (39%, one-sided 95% CI lower bound 28%; two-sided 90% CI 28-51) were progression free at 12 weeks. On April 6, 2011, the protocol was amended to include three additional patients in the IGF-1R-positive soft-tissue sarcoma group (total of 57 patients) and nine more in the IGF-1R-negative group (total of 63 patients). There were 2546 adverse events reported during the study, 214 (8%) of which were grade 3-4. The most common grade 3-4 toxicities in the 174 treated patients were anaemia in 16 (9%) patients, hyperglycaemia in 18 (10%), hypophosphataemia in 16 (9%), lymphopenia in 25 (14%), oral mucositis in 19 (11%), and thrombocytopenia in 19 (11%). INTERPRETATION: The combination of cixutumumab and temsirolimus shows clinical activity in patients with sarcoma and forms a basis for future trials. However, IGF-1R expression by immunohistochemistry is not predictive of clinical outcome after treatment with this combination. FUNDING: National Cancer Institute and CycleforSurvival Fund, Memorial Sloan-Kettering Cancer Center.

Cytoreductive surgery and hyperthermic intraperitoneal chemotherapy for the treatment of peritoneal sarcomatosis.

BACKGROUND: The prognosis of peritoneal sarcomatosis is generally poor and conventional treatments for this disease process are mostly ineffective. The use of cytoreductive surgery (CRS) with hyperthermic intraperitoneal chemotherapy (HIPEC) as an aggressive locoregional treatment option remains controversial. METHODS: We reviewed 13 patients with peritoneal sarcomatosis who underwent CRS and closed-abdomen HIPEC with cisplatin and doxorubicin between March 2007 and March 2010. None of the patients was diagnosed with GIST or uterine leiomyosarcoma. Both disease-free survival (DFS) and overall survival (OS) were evaluated. Completeness of cytoreduction (CC) and peritoneal cancer index (PCI) were assessed. RESULTS: There was no operative mortality. Median follow-up was 12 (range, 4­43) months. Peritoneal disease progression occurred in six patients, distant metastases alone in none, and both in two patients. Median DFS and OS were 11 and 12 months, respectively. Completeness of cytoreduction significantly affected survival. Mean DFS and OS in those patients where a CC-0 was achieved was 27.25 ± 5.71 (median, 20) months and 35.25 ± 4.75 months (median, not reached). In contrast, patients with gross residual disease (CC ≥ 1) had a DFS of 4.25 ± 1.43 months (median, 4 months; P = 0.03) and an OS of 5.25 ± 2.36 months (median, 4 months; P = 0.02). In addition, PCI influenced survival when evaluated by univariate analysis. Using multivariate analysis, completeness of cytoreduction was the only covariate influencing overall survival (P = 0.012). CONCLUSIONS: A complete cytoreduction and low PCI score appear to be important factors in considering CRS and HIPEC for patients with peritoneal sarcomatosis.

A phase I study of continuous infusion cilengitide in patients with solid tumors.

BACKGROUND: Cilengitide (EMD121974) is a cyclized pentapeptide that is a potent and selective integrin antagonist which has shown activity in malignant gliomas. In all previous studies, cilengitide has been administered in an intermittent fashion. However, cilengitide has a short half-life of 3-5 h with no evidence of drug accumulation. These data prompted the initiation of this phase I study of continuous infusion cilengitide. METHODS: Cilengitide was administered as a continuous infusion without break in 4-week cycles. Plasma samples for pharmacokinetic studies were obtained weekly in cycle 1 immediately prior to and 2 h after infusion bag change. RESULTS: Thirty-five patients were treated (median age 56; 23 males) at dose levels of 1, 2, 4, 8, 12, 18, 27, and 40 mg/h. Toxicities were limited to grade ≤ 2 and showed no relation to dose. Fatigue was most common (17%), while all other toxicities were reported in <10% of patients. No dose-limiting toxicities were observed, and therefore the maximum tolerated dose was not reached. Pharmacokinetic analysis showed that values for clearance and volume of distribution were comparable across dose levels, and the steady-state concentration increased proportionally with dose. CONCLUSIONS: Cilengitide can be safely administered as a continuous infusion at doses up to at least 40 mg/h, which represents the maximum feasible dose due to drug solubility and delivery limitations. The pharmacokinetics of continuous infusion cilengitide are linear and consistent with the results obtained using a twice weekly infusion.

The quinoxaline anti-tumor agent (R+)XK469 inhibits neuroblastoma tumor growth.

The quinoxaline anti-tumor agent (R+)XK469 mediates its effects by topoisomerase IIB inhibition. This report describes a 14-year old with relapsed neuroblastoma who experienced disease stabilization for 14 months while receiving (R+)XK469 monotherapy. Due to this favorable response, laboratory studies were undertaken to determine efficacy in the preclinical setting. (R+)XK469 inhibited proliferation, caused G(2) cell cycle arrest of neuroblastoma cells in vitro, and inhibited growth of neuroblastoma xenograft tumors. These preclinical results, coupled with the favorable clinical response, demonstrate that (R+)XK469 and similar anti-tumor agents may be effective in the treatment of high-risk neuroblastoma and warrant further testing.

Phase II randomised discontinuation trial of brivanib in patients with advanced solid tumours.

BACKGROUND: Brivanib is a selective inhibitor of vascular endothelial growth factor and fibroblast growth factor (FGF) signalling. We performed a phase II randomised discontinuation trial of brivanib in 7 tumour types (soft-tissue sarcomas [STS], ovarian cancer, breast cancer, pancreatic cancer, non-small-cell lung cancer [NSCLC], gastric/esophageal cancer and transitional cell carcinoma [TCC]). PATIENTS AND METHODS: During a 12-week open-label lead-in period, patients received brivanib 800 mg daily and were evaluated for FGF2 status by immunohistochemistry. Patients with stable disease at week 12 were randomised to brivanib or placebo. A study steering committee evaluated week 12 response to determine if enrolment in a tumour type would continue. The primary objective was progression-free survival (PFS) for brivanib versus placebo in patients with FGF2-positive tumours. RESULTS: A total of 595 patients were treated, and stable disease was observed at the week 12 randomisation point in all tumour types. Closure decisions were made for breast cancer, pancreatic cancer, NSCLC, gastric cancer and TCC. Criteria for expansion were met for STS and ovarian cancer. In 53 randomised patients with STS and FGF2-positive tumours, the median PFS was 2.8 months for brivanib and 1.4 months for placebo (hazard ratio [HR]: 0.58, p = 0.08). For all randomised patients with sarcomas, the median PFS was 2.8 months (95% confidence interval [CI]: 1.4-4.0) for those treated with brivanib compared with 1.4 months (95% CI: 1.3-1.6) for placebo (HR = 0.64, 95% CI: 0.38-1.07; p = 0.09). In the 36 randomised patients with ovarian cancer and FGF2-positive tumours, the median PFS was 4.0 (95% CI: 2.6-4.2) months for brivanib and 2.0 months (95% CI: 1.2-2.7) for placebo (HR: 0.56, 95% CI: 0.26-1.22). For all randomised patients with ovarian cancer, the median PFS in those randomised to brivanib was 4.0 months (95% CI: 2.6-4.2) and was 2.0 months (95% CI: 1.2-2.7) in those randomised to placebo (HR = 0.54, 95% CI: 0.25-1.17; p = 0.11). CONCLUSION: Brivanib demonstrated activity in STS and ovarian cancer with an acceptable safety profile. FGF2 expression, as defined in the protocol, is not a predictive biomarker of the efficacy of brivanib.

Histologic response of dose-intense chemotherapy with preoperative hypofractionated radiotherapy for patients with high-risk soft tissue sarcomas.

BACKGROUND: The authors studied a dose-intense regimen of epirubicin and ifosfamide with hypofractionated preoperative radiotherapy for high-risk soft tissue sarcomas. The primary objective was estimation of the rate of >or=95% pathologic necrosis. METHODS: Twenty-five patients with intermediate-grade or high-grade, localized soft tissue sarcomas of the extremity or body wall measuring >5 cm were treated with epirubicin at a dose of 30 mg/m(2)/day on Days 1 to 4 and ifosfamide at a dose of 2.5 g/m(2)/day on Days 1 to 4 every 21 days for 3 preoperative and 3 postoperative cycles. A total of 28 grays of radiation was administered over 8 fractions during Cycle 2 of preoperative therapy (epirubicin was omitted). RESULTS: Sixteen patients (64%) completed all chemotherapy cycles and the average delivered dose intensity relative to intended therapy was 69%. Twenty-one patients (84%) experienced grade 4 toxicity (using the National Cancer Institute Common Terminology Criteria for Adverse Events [version 2.0]), which was predominantly hematologic. Notable toxicities included neutropenic fever (40%), ifosfamide-induced encephalopathy (24%), and grade 3/4 anemia (64%). Postoperative wound complications requiring a surgical procedure occurred in 20% of patients. The rate of >or=95% pathologic necrosis was 40% (95% confidence interval [95% CI], 21-59%). Estimates of 2-year overall and disease-free survival were 84% (95% CI, 66-100%) and 62% (95% CI, 37-86%), respectively. CONCLUSIONS: A high rate of >or=95% pathologic necrosis was noted with this aggressive chemoradiotherapy regimen. The occurrence of significant acute toxicities limited the delivery of the intended dose intensity.

A phase II study of ixabepilone (BMS-247550) in metastatic renal-cell carcinoma.

INTRODUCTION: Ixabepilone (BMS-247550) is a semi-synthetic analog of epothilone B that has been characterized as a microtubule stabilizing agent with a mechanism of action distinct from taxanes. Suggestion of activity in renal cell carcinoma (RCC) has been seen in early clinical studies. METHODS: Eligible patients had metastatic RCC as well as ECOG performance status 0-2 and normal organ function. Patients received ixabepilone at a dose of 40 mg/m2 intravenously over three hours every 21 days. There was no restriction on RCC histology or prior treatment type, but prior treatment with tubule inhibitors was not allowed. The primary endpoint was RECIST defined response and radiographic evaluations were performed every three cycles. Toxicity evaluations utilized CTCAE v3.0 and were performed every cycle. Using a Simon two-stage optimal design with alpha = 0.1, beta = 0.1, a null hypothesized response rate of 0.05 and an alternative response rate of 0.2, an initial 12 patients were to be accrued with full accrual of 37 patients if at least one response were observed. RESULTS: A median of five cycles were administered. No objective responses were observed in the first 12 evaluable patients, and six patients showed stable disease for more than 18 weeks on therapy. Median time to progression among those with objective progression was nine weeks. One patient experienced grade 4 anemia and lymphopenia. Grade 3 adverse events included lymphopenia, neutropenia, leukopenia, diarrhea, and infection. Common grade 2 toxicities included alopecia, fatigue and anemia. CONCLUSION: Ixabepilone administered at a dose of 40 mg/m2 every 21 days should not be advanced for further study in metastatic RCC. Given previous results, however, other dosing schedules may be worthy of further investigation.

An Evaluation of Psychosocial and Religious Belief Differences in a Diverse Racial and Socioeconomic Urban Cancer Population.

Despite years of research aimed at decreasing the cancer mortality rates, the disparity between African-Americans and whites continues to grow. The fundamental psychosocial and belief differences that may mediate these disparities are poorly studied and rarely disentangle race versus specific socioeconomic status (SES) effects. In this study, breast, colon, and lung cancer patients presenting for their first oncology appointment completed a self-administered survey utilizing previously validated instruments regarding psychosocial and belief factors. Results were analyzed by self-identified race, income, and education. In total, 161 African-American (37 %) and 269 white (63 %) new oncology patients with breast (47 %), colon (16 %), or lung (37 %) cancer enrolled. African-Americans were more likely to be in the US$<20,000 income group (45 vs. 9 %) but 21 % had incomes US$>60,000. Apparent racial differences in health literacy and cancer knowledge were primarily mediated by income and education. Significant racial differences in God's perceived role in their cancer remained after adjustments for income and education with African-Americans more likely to feel that God was in control of their cancer (67 vs. 30 %). These findings suggest the need for a more nuanced understanding of how race and socioeconomic status exert both independent and interrelated effects in the health care setting. Only then can effective interventions that reduce disparities in survival be designed. This study adds further substantive evidence to the crucial importance of God's perceived role in the cancer experience for African-Americans. An important area for future research is to examine whether these racial differences in religious belief are also associated with differences in health-related behavior and medical decision-making.

Genetic variants in the UDP-glucuronosyltransferase 1A1 gene predict the risk of severe neutropenia of irinotecan.

PURPOSE: Severe toxicity is commonly observed in cancer patients receiving irinotecan. UDP-glucuronosyltransferase 1A1 (UGT1A1) catalyzes the glucuronidation of the active metabolite SN-38. This study prospectively evaluated the association between the prevalence of severe toxicity and UGT1A1 genetic variation. PATIENTS AND METHODS: Sixty-six cancer patients with advanced disease refractory to other treatments received irinotecan 350 mg/m(2) every 3 weeks. Toxicity and pharmacokinetic data were measured during cycle 1. UGT1A1 variants (-3279G>T, -3156G>A, promoter TA indel, 211G>A, 686C>A) were genotyped. RESULTS: The prevalence of grade 4 neutropenia was 9.5%. Grade 4 neutropenia was much more common in patients with the TA indel 7/7 genotype (3 of 6 patients; 50%) compared with 6/7 (3 of 24 patients; 12.5%) and 6/6 (0 of 29 patients; 0%) (P =.001). The TA indel genotype was significantly associated with the absolute neutrophil count nadir (7/7 < 6/7 < 6/6, P =.02). The relative risk of grade 4 neutropenia was 9.3 (95% CI, 2.4 to 36.4) for the 7/7 patients versus the rest of the patients. Pretreatment total bilirubin levels (mean +/- standard deviation) were significantly higher in patients with grade 4 neutropenia (0.83 +/- 0.08 mg/dL) compared to those without grade 4 neutropenia (0.47 +/- 0.03 mg/dL; P <.001). The -3156G>A variant seemed to distinguish different phenotypes of total bilirubin within the TA indel genotypes. The -3156 genotype and the SN-38 area under the concentration versus time curve were significant predictors of ln(absolute neutrophil count nadir; r(2) = 0.51). CONCLUSION: UGT1A1 genotype and total bilirubin levels are strongly associated with severe neutropenia, and could be used to identify cancer patients predisposed to the severe toxicity of irinotecan. The hypothesis that the -3156G>A variant is a better predictor of UGT1A1 status than the previously reported TA indel requires further testing.

Dose-ranging study of the safety and pharmacokinetics of atrasentan in patients with refractory malignancies.

PURPOSE: Atrasentan is an orally bioavailable selective antagonist of the endothelin receptor ET(A). Due to the potential activity of this agent against prostate cancer, the majority of subjects enrolled in prior studies had been male. This Phase I study sought to determine the toxicity and pharmacokinetics of daily atrasentan in a population of both female and male subjects with advanced malignancies. EXPERIMENTAL DESIGN: Patients with refractory malignancies received atrasentan once daily at doses ranging from 5 mg to 75 mg. At least 3 subjects were treated at each dose level before enrollment began at the next higher dose level. Enrollment for specific dose levels was expanded if any subject experienced serious drug-related toxicity. Plasma concentration profiles for atrasentan were determined after dosing on days 1 and 28. RESULTS: Thirty-five patients received atrasentan at doses from 5 mg to 75 mg. The most frequent drug-related adverse events were headache (60%), rhinitis (49%), and peripheral edema (31%). These toxicities were mild to moderate in severity and reversible on cessation of treatment. Dose escalation was stopped at the 75-mg dose level due to the occurrence of three severe adverse events (2 hyponatremia and 1 hypotension). Atrasentan was rapidly absorbed after oral administration; mean time to maximum observed concentration ranged from 0.3 to 1.7 h. Terminal elimination half-life averaged 26 h. No significant difference between sexes was found in any atrasentan pharmacokinetic parameter tested, including maximum observed plasma concentration, time to maximum observed concentration, minimum observed plasma concentration, area under the plasma concentration-time curve, and elimination rate constant. CONCLUSIONS: Atrasentan is well tolerated in both female and male cancer patients at doses of up to 60 mg/day with dose-limiting toxicity observed at 75 mg/day. The most frequently observed toxicities were headache, rhinitis, and edema. There was no statistically significant difference in atrasentan pharmacokinetics between sexes.

A phase I trial of pharmacologic modulation of irinotecan with cyclosporine and phenobarbital.

The anticancer agent irinotecan has been demonstrated to improve the survival rate in patients with metastatic colorectal cancer. Its usage has been limited by severe toxicity. To modulate irinotecan pharmacokinetics and reduce the prevalence of severe toxicity, patients were treated with cyclosporine (INN, ciclosporin) and the irinotecan dose was increased from 25 to 72 mg/m2 weekly. Phenobarbital was then added, allowing dose escalation to 144 mg/m2. Dose-limiting toxicities were neutropenia and diarrhea. Irinotecan was well tolerated at the recommended phase II dose of 120 mg/m2, with a 6% prevalence of grade 4 neutropenia and an 18% prevalence of grade 3 diarrhea. Cyclosporine increased 7-ethyl-10-hydroxycamptothecin (SN-38) area under the concentration-time curve (AUC) by 23% to 630% and reduced irinotecan clearance by 39% to 64% when compared with historical controls. Phenobarbital increased irinotecan clearance by 27% (P < or =.001) and reduced SN-38 AUC by 75% (P < or =.001) when compared with patients treated with cyclosporine alone. Five partial responses were observed. Pharmacokinetic modulation of irinotecan with cyclosporine and phenobarbital has been demonstrated; further studies are necessary to evaluate whether this strategy improves the therapeutic index.

Dose-finding and pharmacokinetic study to optimize the dosing of irinotecan according to the UGT1A1 genotype of patients with cancer.

PURPOSE: The risk of severe neutropenia from treatment with irinotecan is related in part to UGT1A1*28, a variant that reduces the elimination of SN-38, the active metabolite of irinotecan. We aimed to identify the maximum-tolerated dose (MTD) and dose-limiting toxicity (DLT) of irinotecan in patients with advanced solid tumors stratified by the *1/*1, *1/*28, and *28/*28 genotypes. PATIENTS AND METHODS: Sixty-eight patients received an intravenous flat dose of irinotecan every 3 weeks. Forty-six percent of the patients had the *1/*1 genotype, 41% had the *1/*28 genotype, and 13% had the *28/*28 genotype. The starting dose of irinotecan was 700 mg in patients with the *1/*1 and *1/*28 genotypes and 500 mg in patients with the *28/*28 genotype. Pharmacokinetic evaluation was performed at cycle 1. RESULTS: In patients with the *1/*1 genotype, the MTD was 850 mg (four DLTs per 16 patients), and 1,000 mg was not tolerated (two DLTs per six patients). In patients with the *1/*28 genotype, the MTD was 700 mg (five DLTs per 22 patients), and 850 mg was not tolerated (four DLTs per six patients). In patients with the *28/*28 genotype, the MTD was 400 mg (one DLT per six patients), and 500 mg was not tolerated (three DLTs per three patients). The DLTs were mainly myelosuppression and diarrhea. Irinotecan clearance followed linear kinetics. At the MTD for each genotype, dosing by genotype resulted in similar SN-38 areas under the curve (AUCs; r(2) = 0.0003; P = .97), but the irinotecan AUC was correlated with the actual dose (r(2) = 0.39; P < .001). Four of 48 patients with disease known to be responsive to irinotecan achieved partial response. CONCLUSION: The UGT1A1*28 genotype can be used to individualize dosing of irinotecan. Additional studies should evaluate the effect of genotype-guided dosing on efficacy in patients receiving irinotecan.

Phase I studies of sirolimus alone or in combination with pharmacokinetic modulators in advanced cancer patients.

PURPOSE: Sirolimus is the eponymous inhibitor of the mTOR; however, only its analogs have been approved as cancer therapies. Nevertheless, sirolimus is readily available, has been well studied in organ transplant patients, and shows efficacy in several preclinical cancer models. EXPERIMENTAL DESIGN: Three simultaneously conducted phase I studies in advanced cancer patients used an adaptive escalation design to find the dose of oral, weekly sirolimus alone or in combination with either ketoconazole or grapefruit juice that achieves similar blood concentrations as its intravenously administered and approved prodrug, temsirolimus. In addition, the effect of sirolimus on inhibition of p70S6 kinase phosphorylation in peripheral T cells was determined. RESULTS: Collectively, the three studies enrolled 138 subjects. The most commonly observed toxicities were hyperglycemia, hyperlipidemia, and lymphopenia in 52%, 43%, and 41% of subjects, respectively. The target sirolimus area under the concentration curve (AUC) of 3,810 ng-h/mL was achieved at sirolimus doses of 90, 16, and 25 mg in the sirolimus alone, sirolimus plus ketoconazole, and sirolimus plus grapefruit juice studies, respectively. Ketoconazole and grapefruit juice increased sirolimus AUC approximately 500% and 350%, respectively. Inhibition of p70 S6 kinase phosphorylation was observed at all doses of sirolimus and correlated with blood concentrations. One partial response was observed in a patient with epithelioid hemangioendothelioma. CONCLUSION: Sirolimus can be feasibly administered orally, once weekly with a similar toxicity and pharmacokinetic profile compared with other mTOR inhibitors and warrants further evaluation in studies of its comparative effectiveness relative to recently approved sirolimus analogs.

Two drug interaction studies of sirolimus in combination with sorafenib or sunitinib in patients with advanced malignancies.

PURPOSE: Sirolimus is the prototypical mTOR inhibitor. Sorafenib and sunitinib are small molecule inhibitors of multiple kinases including VEGF receptor (VEGFR) kinases. These agents have different mechanisms of action, providing a strong rationale for combination. EXPERIMENTAL DESIGN: Patients with advanced cancer were assigned to receive either sirolimus or the VEGFR inhibitor alone for a 2-week lead-in period, followed by combination therapy. The primary end point of each trial was to determine whether a drug interaction exists between sirolimus and either sorafenib or sunitinib, as defined by a difference in C(max) for each drug alone compared with its C(max) during combination therapy. RESULTS: The sorafenib and sunitinib trials enrolled 34 and 23 patients, respectively. There were no clinically significant differences in C(max) for any of the drugs alone compared with the C(max) during combination therapy. Toxicity profiles were similar to those expected for each drug alone. One patient with adrenal cortical cancer had a partial response to sirolimus and sunitnib. CONCLUSIONS: Sirolimus can be safely combined with sorafenib or sunitinib. Our trial design is feasible and informative in screening for potential drug-drug interactions, using a relatively small number of patients and limited pharmacokinetic sampling.

Phase I study of dose-escalated busulfan with fludarabine and alemtuzumab as conditioning for allogeneic hematopoietic stem cell transplant: reduced clearance at high doses and occurrence of late sinusoidal obstruction syndrome/veno-occlusive disease.

Disease recurrence after allogeneic hematopoietic cell transplant (alloHCT) remains common, making improvements in conditioning regimens desirable. A dose-response relationship between busulfan exposure and outcome is known. Using individual real-time monitoring of the busulfan area under the curve (AUC), we aimed to determine the maximum-tolerated busulfan AUC in a conditioning regimen with fludarabine/alemtuzumab. Thirty-six patients with advanced hematologic malignancies were treated. Busulfan levels after a test dose and conditioning dose 1 allowed targeting of subsequent AUCs and dose-escalation above the starting AUC of 4800 µmol-min/L. Clearance of busulfan test doses was not always sufficiently predictive of treatment dose AUC and, on average, test dose clearance was faster than treatment dose clearance. When the study was modified to use conditioning dose 1 pharmacokinetics instead, accurately targeted treatment AUCs were achieved, and dose-escalation was possible. Severe, late-occurring sinusoidal obstruction syndrome/veno-occlusive disease (SOS/VOD) was the dose-limiting toxicity seen in 5/8 patients at an AUC level of 6800 µmol-min/L. The risk for SOS/VOD correlated with the highest observed AUC (AUC(max)) rather than with the average cumulative AUC (AUC(avg)). Busulfan dose-escalation to a maximum-tolerated AUC of 5800 µmol-min/L-higher than that achieved by current standard busulfan regimens-was accurate and achievable using real-time pharmacokinetics monitoring of the first conditioning dose. This AUC is now being studied in phase II for patients receiving busulfan/fludarabine/alemtuzumab as alloHCT conditioning.

Primary tumor necrosis predicts distant control in locally advanced soft-tissue sarcomas after preoperative concurrent chemoradiotherapy.

PURPOSE: Various neoadjuvant approaches have been evaluated for the treatment of locally advanced soft-tissue sarcomas. This retrospective study describes a uniquely modified version of the Eilber regimen developed at the University of Chicago. METHODS AND MATERIALS: We treated 34 patients (28 Stage III and 6 Stage IV) with locally advanced soft-tissue sarcomas of an extremity between 1995 and 2008. All patients received preoperative therapy including ifosfamide (2.5 g/m2 per day for 5 days) with concurrent radiation (28 Gy in 3.5-Gy daily fractions), sandwiched between various chemotherapy regimens. Postoperatively, 47% received further adjuvant chemotherapy. RESULTS: Most tumors (94%) were Grade 3, and all were T2b, with a median size of 10.3 cm. Wide excision was performed in 29 patients (85%), and 5 required amputation. Of the resected tumor specimens, 50% exhibited high (> or =90%) treatment-induced necrosis and 11.8% had a complete pathologic response. Surgical margins were negative in all patients. The 5-year survival rate was 42.3% for all patients and 45.2% for Stage III patients. For limb-preservation patients, the 5-year local control rate was 89.0% and reoperation was required for wound complications in 17.2%. The 5-year freedom-from-distant metastasis rate was 53.4% (Stage IV patients excluded), and freedom from distant metastasis was superior if treatment-induced tumor necrosis was 90% or greater (84.6% vs. 19.9%, p = 0.02). CONCLUSIONS: This well-tolerated concurrent chemoradiotherapy approach yields excellent rates of limb preservation and local control. The resulting treatment-induced necrosis rates are predictive of subsequent metastatic risk, and this information may provide an opportunity to guide postoperative systemic therapies.