Hemodynamic correlates of proteinuria in chronic kidney disease

BACKGROUND AND OBJECTIVES

Brachial artery measures of BP are associated with increasing degrees of proteinuria. Whether central measures of BP or vascular stiffness are associated with increased risk of proteinuria in patients with chronic kidney disease (CKD) is unknown.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

Measurements of central and brachial artery BP, and aortic pulse wave velocity (PWV) were performed in a cross-sectional cohort of patients with CKD (n = 2144) from the Chronic Renal Insufficiency Cohort (CRIC) study to determine factors which predict increased risk of proteinuria. Multivariate analysis stratified by diabetes included age, ethnicity, gender, estimated glomerular filtration rate (GFR), waistline, smoking, heart rate, and medications to evaluate the relationship of hemodynamic factors and proteinuria.

RESULTS

Brachial artery systolic BP (SBP) was important as an explanatory factor for variations in proteinuria among both diabetics (R(2) = 0.40, P < 0.0001) and non diabetics (R(2) = 0.38, P < 0.001). Measures of peripheral pulse pressure (PP), central SBP, and central pulse pressure added little to the explained variation in proteinuria beyond brachial artery SBP, whereas PWV as a measure of vascular stiffness incrementally accounted for a significant portion of variation in proteinuria beyond that explained by brachial artery SBP in diabetics (R(2) = 0.42, P < 0.001) but not non diabetics.

CONCLUSIONS

Brachial artery SBP and PWV are both associated with variations in proteinuria in patients with CKD.

Relationship of estimated GFR and coronary artery calcification in the CRIC (Chronic Renal Insufficiency Cohort) Study

BACKGROUND

Coronary artery calcification (CAC) is associated with increased mortality risk in the general population. Although individuals with chronic kidney disease (CKD) are at markedly increased mortality risk, the incidence, prevalence, and prognosis of CAC in CKD are not well understood.

STUDY DESIGN

Cross-sectional observational study.

SETTING & PARTICIPANTS

Analysis of 1,908 participants who underwent coronary calcium scanning as part of the multiethnic CRIC (Chronic Renal Insufficiency Cohort) Study.

PREDICTOR

Estimated glomerular filtration rate (eGFR) computed using the Modification of Diet in Renal Disease (MDRD) Study equation, stratified by race, sex, and diabetic status. eGFR was treated as a continuous and a categorical variable compared with the reference value of >60 mL/min/1.73 m(2).

MEASUREMENTS

CAC detected using computed tomography (CT) using either an Imatron C-300 electron beam computed tomography (CT) scanner or multidetector CT scanner. CAC was computed using Agatston score as a categorical variable. Analyses were performed using ordinal logistic regression.

RESULTS

We found a strong and graded relationship between lower eGFR and increasing CAC. In unadjusted models, ORs increased from 1.68 (95% CI, 1.23-2.31) for eGFR of 50-59 mL/min/1.73 m(2) to 2.82 (95% CI, 2.06-3.85) for eGFR <30 mL/min/1.73 m(2). Multivariable adjustment only partially attenuated the results (OR, 1.53; 95% CI, 1.07-2.20) for eGFR <30 mL/min/1.73 m(2).

LIMITATIONS

Use of eGFR rather than measured GFR.

CONCLUSIONS

We showed a graded relationship between severity of CKD and CAC independent of traditional risk factors. These findings support recent guidelines that state that if vascular calcification is present, it should be considered as a complementary component to be included in the decision making required for individualizing CKD treatment.

The effect of a handwashing intervention on preschool educator beliefs, attitudes, knowledge and self-efficacy

This paper describes the effect of a preschool hygiene intervention program on psychosocial measures of educators regarding handwashing and communicable pediatric disease. A cluster-randomized trial, with randomization at the level of the preschool, was run in 40 Jerusalem preschool classrooms. Eighty preschool educators participated. The program used a multipronged approach which included elements aimed at staff, children, parents, school nurses and the classroom environment. Frontal lectures by medical, epidemiological and educational experts, along with printed materials and experiential learning, were provided to staff. Responses from a validated survey instrument were used to build four scales for each respondent regarding beliefs, attitudes, self-efficacy and knowledge. The scales were built on a Likert-type 1-7 scale (1 = minimum, 7 = maximum). The effect of the intervention was tested using mixed model analysis of variance. Response was received from 92.5% of educators. Educators believed that handwashing could affect health (mean = 5.5, SD = 1.1), had high levels of self-efficacy (mean = 6.1, SD = 0.9) and had positive attitudes toward handwashing (mean = 5.7, SD = 1.2). Knowledge was affected by the intervention (intervention: mean = 6.2, SD = 0.7; control: mean = 5.8, SD = 0.8). The combination of positive attitudes toward handwashing among educators and the program's effectiveness in imparting knowledge helped to create a sustained social norm of handwashing among many children in disparate locations.

Final results: A dose escalation phase I study of ARQ 197, a selective c-Met inhibitor, in patients with metastatic solid tumors

3548

Background: ARQ 197 is a selective, non-ATP competitive inhibitor of c-Met, a receptor tyrosine kinase implicated in tumor cell migration, invasion, and proliferation. Methods: This phase I dose escalation study enrolled patients (pts) with metastatic solid tumors to determine the drug's safety profile, maximum tolerated dose (MTD), recommended phase 2 dose (RP2D), pharmacokinetics (PK), and preliminary antitumor activity. Dose escalation followed an accelerated titration design and was modified to the traditional escalation design (3+3 pts) once grade 2 toxicity was observed. ARQ 197 was initially administered orally twice daily (BID) for 2 weeks followed by 1 week off and then modified to evaluate continuous BID dosing based on favorable safety data. Intra-patient dose-escalation was allowed in this study. Additional pts were enrolled and treated at the 360 mg bid continuous dose, which was determined to be the RP2D in another phase I clinical trial. Results: To date, 65 pts (38 male/27 female; median age 61; 9 colon/colorectal, 8 renal cell carcinoma/kidney, 6 ovarian, 6 sarcoma, 5 lung cancer and 31 others) have been treated at 11 dose levels (10 mg bid to 360 mg bid). All treated pts achieved plasma drug concentrations significantly above in vitro IC50 values. The most common drug-related adverse events (AEs) were fatigue (18.5%) and nausea (12.3%). One case each of the following drug-related serious AEs were reported in 4 pts: anemia, leukopenia, neutropenia, thrombocytopenia, dehydration, liver failure, abdominal pain, nausea, and vomiting. Three pts with neuroendocrine, prostate, or testicular cancer achieved a partial response (PR), 32 demonstrated stable disease (SD) and 13 progressed. The 3 PR pts were initially treated at 10, 40 or 90 mg BID respectively. Their doses were escalated to 50, 70, or 120 mg BID respectively after 18 to 33 weeks on treatment. An overall response rate of 6.3% and a disease control rate (CR+PR+SD) of 72.9% were demonstrated among 48 pts who are evaluable for efficacy. Conclusions: ARQ 197 has demonstrated a favorable safety profile up to the dose of 360 mg bid. Preliminary evidence of anti-cancer activity was observed. Final study data on drug safety, PK and efficacy will be presented.

[Table: see text]

Analysis of biomarkers during early phase clinical development of AMG 479, an investigational fully human monoclonal antibody antagonist of type 1 insulin-like growth factor receptor (IGF-1R)

3545

Background: AMG 479 showed anti-tumor activity in a phase 1 (P1) and phase 1b (P1b) trial (Tolcher, J Clin Oncol. 2007;25:3002; Sarantopoulos, J Clin Oncol. 2008;26:3583). We sought to identify predictive markers of response to AMG 479 in these trials by analyzing pharmacodynamic (PD) markers in serum, and expression and mutations of regulators of the IGF-1R pathway in tumors. Methods: Patients (pts) had advanced solid tumors and received AMG 479 (1–20 mg/kg Q2W) in the P1 trial or AMG 479 (6 or 12 mg/kg Q2W) + panitumumab (6 mg/kg Q2W) or gemcitabine (1,000 mg/m2 QW) in the P1b trial. Serum levels of IGF-1 and IGFBP-3 were measured pre dose on Day -1 and post dose at various time points. In the P1 trial, we examined relationships between tumor response (by RECIST) and: 1) levels of IGF-1 and IGFBP-3 (at baseline or PD change from baseline); 2) somatic mutations in key genes (including K-ras, and PTEN) of the IGF-1R pathway (in archival tumors); and 3) expression of PTEN (measured by immunohistochemistry in archival tumors). Results: Serum IGF-1 and IGFBP-3 increased in a concentration-dependent manner between 1 and 12 mg/kg AMG 479, with an apparent plateau between 12 and 20 mg/kg AMG 479. Baseline and PD changes in IGF-1 and IGFBP-3 were not substantially different in pts with a tumor response compared with those without a tumor response. A partial response to AMG 479 was observed in a pt with an activating K-ras mutation. No responses have been observed in tumors that lack expression of PTEN. Conclusions: The PD results suggest near complete biochemical coverage at 12-mg/kg AMG 479. Our hypothesis-generating analyses suggest that: 1) pre and postdose levels of IGF-1 and IGFBP-3 do not predict response to single-agent AMG 479; 2) activating K-ras mutations do not appear to preclude responsiveness to single-agent AMG 479 (in contrast to EGFR inhibitors); 3) expression and mutations of regulators of the PI3K/Akt pathway downstream of IGF-1R activation may be useful in predicting response to AMG 479.

[Table: see text]

Phase I dose escalation trial (ARQ 197–111) evaluating combination of selective c-Met inhibitor ARQ 197 and erlotinib

3549

Background: ARQ197 (A) is a selective, non-ATP competitive inhibitor of c-Met, a receptor tyrosine kinase implicated in tumor cell migration, invasion, and proliferation. Phase I data for ARQ 197 monotherapy is previously reported. Recent evidence suggests c-Met promotes resistance to EGFR-inhibition by driving ERBB3 (HER3)-dependent PI3K activation. Dual EGFR-Met inhibition is now proposed as a strategy for overcoming resistance to EGFR-inhibition. Methods: Patients (pts) were enrolled in a sequential-cohort dose-escalation trial seeking to define safety, tolerability, pharmacokinetics (PK), and preliminary anti-tumor activity of A in combination with 150 mg daily oral erlotinib (E). Oral A was administered at escalating doses of 120, 240, and 360 mg bid. Intra-patient dose escalation was allowed in the absence of dose-limiting toxicity (DLT) through 1 cycle of therapy (21 days). Results: 25 pts (10 F/15 M; mean 60.5 yrs) received EA combination with starting A dose of 120 (8 pts), 240 (4 pts), and 360 (13 pts) mg bid. PK data reveal linear kinetics through 360 bid and no evidence of drug-drug interaction. Adverse events (AEs) considered related to combination therapy were reported in 13 (52%) of pts incl.sinus bradycardia (5 pts), fatigue (5 pts), rash (4 pts), itching (3 pts), and diarrhea (3 pts). 2 pts experienced related serious AEs incl. neutropenia (360 bid) and sinus bradycardia (240 bid). 1 death occurring on-study was considered unrelated to study drug. 9/10 evaluable pts demonstrated disease stabilization (SD) as their best RECIST response (5.9–27.1+ wks). Tumor regressions (2.3%-19.4%) were observed in 4/10 evaluable pts. Of note, 3/3 evaluable pts with NSCLC achieved SD for durations (14–32 wks) exceeding median PFS in BR.21 (9.7 wks). Conclusions: Continuous therapy with EA combination appears well tolerated and without drug-drug interaction. While no formal MTD was identified, a phase 2 combination dose (R2PD) of 360 mg bid A + 150 mg daily E is recommended. This RP2D is currently being investigated in an ongoing randomized trial comparing EA to E monotherapy in 2nd/3rd line NSCLC.

[Table: see text]

Phase I study of bavituximab, a novel anti-phosphatidylserine monoclonal antibody in patients with advanced refractory cancer: Preliminary results

1080

Background: Aminophospholipid are normally expressed on damaged or apoptotic cells, as well as on the intravascular surface of EC of vessels feeding the tumor as a result of the tumor microenvironment (e.g., hypoxia, reactive oxygen species). Bavituximab (B), a novel monoclonal antibody against PS, has demonstrated preclinical anti-tumor activity by eliciting both innate and adaptive immune responses specific to tumor vasculature. Here we report preliminary results of the phase I study in patients (pts) with advanced solid tumors. Methods: This is a phase I, dose escalation, safety, tolerability and pharmacokinetic (PK) study, as well as to define DLT, MTD and/or maximum effective dose (MED) in pts with advanced refractory cancers. Planned cohorts of 6 pts, each were to receive 0.1, 0.3, 1 or 3 mg/kg. Escalation was permitted if mean cohort Cmax ≤ 65 mcg/mL and dose limiting toxicities (DLT) was observed in ≤ 1 of 6 pts. No premedication was planned or needed. DLT was defined as ≥ grade 3 drug-related adverse events (AE), ≥ grade 2 PT, or ≥ grade 3 aPTT. B was given as a 90 minute IV infusion (on days 0, 28, 35, 42 for the first two dose cohorts and 0, 7, 14, 21 for the third- and fourth-dose cohorts. Although not a study endpoint, tumor response was collected at day 56. Results: Data are available for the first 20 pts enrolled (10 breast, 3 colorectal, 2 pancreatic, 1 each of hepatocellular carcinoma, head and neck, melanoma, mesothelioma, and prostate cancer). Cohorts by dose: 0.1 mg/kg (8 pts), 0.3 mg/kg (6pts), and 1 mg/kg (6pts). Median age was 59 years and 70% of pts were females. (Q: see attached Excel file). No DLTs or drug-related severe AEs were reported. Common drug-related AEs were fatigue (7pts), nausea (6 pts), dry skin (3 pts), constipation (2 pts) and dyspnea (2 pts). All AEs were grade 1 or 2 and no dose relationship was observed. PK was dose proportional with mean serum Cmax of 2.3, 5.2 and 16.6 mcg/mL for the 0.1, 0.3 and 1 mg/kg groups, respectively. No accumulation of B was seen after multiple weekly dosing. Conclusions: Single agent bavituximab is well tolerated to date, with a predictable PK profile. Accrual of the last planned cohort is underway. MTD has not been reached. Final results will be available for presentation at the time of the Meeting.

[Table: see text]

A phase Ib dose-escalation study of orally administered MP-470, a multi-kinase inhibitor and supressor of Rad51, in combination with carboplatin doublet containing regimens shows activity in highly refractory solid tumor patients

e13511

Background: MP-470 (MP) is an oral multi-targeted tyrosine kinase inhibitor which inhibits a number of validated tumor targets including c-kit, flt3, and PDGFα. MP470 targets cancer cells by disrupting DNA repair, an important survival pathway in many human cancers. Results presented herein are from two arms of a phase-Ib five arm trial of MP combined with standard of care (SOC) anti- cancer therapies. Methods: MP is administered in combination with SOC in a 21-day cycle. Adults with ECOG PS of 0–2 and malignant disease appropriate for SOC regimens consisting of paclitaxel/carboplatin (PC), carboplatin/etoposide (CE), topotecan, docetaxel, and erlotinib were enrolled. Each arm follows a 3+3 design where MP is escalated based on the modified Fibonacci sequence until the MTD of MP in combination with SOC agents is reached. RECIST and CTCAE are utilized to assess response and safety, respectively. The primary objectives of the study are to determine the MTD, DLTs, and quantify the effects of MP on the PK of SOC agents. Results: Between Dec 2007 and Aug 2008, 26 subjects were enrolled in the PC and CE arms and received a total of 70 cycles (median 2; range, 0–8) of MP at 4 dose levels (100–500 mg/day). Median number of prior therapies was 2 (range, 0–19). Male/Female: 14/12. Median age, 56 years (range, 24–76). Subjects completing ≥ 6 and ≥ 4 cycles were 5 and 7, respectively. Six PRs (2 neuroendocrine, 2 SCLC, 1 NSCLC, 1 small cell of anal canal) and 3 SDs (≥ 4 cycles) was observed. The MTDs have not been reached and DLTs have not been identified. Adverse events occurring in ≥ 15% of patients were myelosuppression, diarrhea, constipation, nausea, reflux, fatigue, alopecia, rash, neuropathy, anorexia, hypokalemia, dyspnea, and myalgias. MP470 did not alter the kinetics of SOC agents. Dose escalation in the PC and CE arms is ongoing. Conclusions: MP470 combined with carboplatin-containing regimens may promote tumor regression and may also sensitize/resensitize tumors to the anticancer effects of such agents. An amendment will be issued to collect tumor tissue biopsy at baseline and during treatment to adequately evaluate DNA damage in tumor tissue.

[Table: see text]

Preliminary results from a phase II study of ARQ 197 in patients with microphthalmia transcription factor family (MiT)-associated tumors

10502

Background: ARQ 197 is a selective, non-ATP competitive inhibitor of c-Met, a receptor tyrosine kinase implicated in tumor cell migration, invasion, and proliferation. The drug has demonstrated a favorable safety profile and preliminary anti-cancer activity in three phase 1 studies. MiT tumors include clear cell sarcoma (CCS), alveolar soft part sarcoma (ASPS), and translocation-associated renal cell carcinoma (TLA RCC) and are linked biologically by a shared activated transcriptional mechanism which directly upregulates c-Met. Tumors with this type of chromosomal abnormality are generally resistant to all approved therapies and, in the absence of complete surgical resection, prove invariably fatal. Methods: This is a multi-center, single arm, two-stage phase 2 trial in patients (pts) 13 years of age or older with MiT tumors. Initially pts received 120 mg ARQ 197 orally twice daily (bid). The protocol was amended in August 2008 to increase the dose to 360 mg bid. If either a complete response (CR) or a partial response (PR) were to be observed in the 23 pts in stage 1, the study would be advanced to stage 2 where 16 additional patients will be enrolled. Tumor responses are measured in 8-week intervals per RECIST criteria. Results: To date, 28 pts (19 females, 9 males; median age = 21; 7 CCS, 17 ASPS, 4 RCC) have been treated. One pt with CCS demonstrated a confirmed PR, 15 pts (10 ASPS, 2 CCS, 3 RCC) demonstrated stable disease (SD) for durations up to 29+ weeks, and 4 pts progressed. An overall response rate of 5% and a disease control rate (CR+PR+SD) of 80% were demonstrated among 20 pts who were evaluable for efficacy. The most common drug-related adverse events (AEs) have been fatigue (35.7%), nausea (35.7%), vomiting (21.4%), decreased hemoglobin (10.7%). and cough (10.7%). To date, only 3 drug-related Grade 3 or 4 AEs have been reported including anemia (2) and decreased neutrophil count (1). No drug-related serious AEs or deaths have been reported. Conclusions: To date, ARQ 197 has demonstrated an extremely favorable safety profile and preliminary evidence of anti-cancer activity in these young pts. The criterion for advancing the study from stage 1 to stage 2 has been met. Stage 2 enrollment is ongoing. Updated data on both dose levels will be presented.

[Table: see text]

Early evidence of tolerability and clinical activity from a phase I study of TRC105 (anti-CD105 antibody) in patients with advanced refractory cancer

3518

Background: CD105 (endoglin) is an angiogenic membrane protein that is over-expressed on proliferating vasculature in solid tumors and up-regulated following anti-VEGF therapy. TRC105 is a human/murine chimeric IgG1 anti-CD105 monoclonal antibody that inhibits angiogenesis and tumor growth via endothelial cell growth inhibition, ADCC, and apoptosis. Methods: The safety and PK of TRC105 were evaluated in patients with refractory cancer. Subjects were to have adequate organ function and no CNS or central thoracic tumors. TRC105 was escalated in cohorts of 3–6 patients to a maximum feasible dose of 1.0 mg/kg i.v. every 2 weeks. Results: 19 ECOG PS 0–1 patients received TRC105 at doses between 0.01–1.0 mg/kg, including 11 men and 8 women aged 37 to 79 years (median 59). One patient experienced dose-limiting toxicity (DLT) at 0.1 mg/kg of grade 4 gastric ulcer bleeding on Day 4 which resolved spontaneously. No other grade 3 or 4 adverse events were reported. Possibly related grade 1–2 adverse events were rare including fatigue, anemia, proteinuria, dysgeusia, diarrhea, flushing, hyperuricemia and intermittent postcoital vaginal bleeding. One patient with castrate-refractory prostate cancer remains on study after 13 months of TRC105 at 0.01 mg/kg with a complete PSA response and bone scan normalization. In addition, 6-month stable disease was seen in a patient with ovarian cancer (CA125 decrease of 16%). Best response also included stable disease (n = 3) and progression (n = 14). Serum TRC105 concentrations expected to saturate CD105 binding sites (> 0.2 ug/mL) were achieved at a dose of 0.3 mg/kg, and concentrations > 10 ug/mL were achieved at 1.0 mg/kg. HAMA became detectable in 1 patient after 3 months of TRC105 therapy. Conclusions: TRC105 is tolerated at doses with evidence of clinical activity. Additional monotherapy and combination studies are planned.

[Table: see text]

Healthy Israel 2020: a visionary national health targeting initiative

This article describes the development of a national health targeting initiative entitled 'Healthy Israel 2020' which was created to enhance the health and wellbeing of Israelis through a variety of health promotion and disease prevention interventions. This initiative builds upon the experience of two major worldwide targeting efforts, "Health People 2010" of the US and the World Health Organization's Health21', as well as lessons learned from other countries. Important philosophical underpinnings are highlighted, particularly the evidence-based nature of the process. Real-world organizational and policy challenges and creative solutions are presented. It is hoped that this report will be of value to others in Israel and elsewhere who are interested in improving the health of their nations.

A phase I study (CA180021-Segment 2) of dasatinib in patients (pts) with advanced solid tumors

14042

Background: SPRYCEL™ is a potent, orally active, multi-targeted kinase inhibitor, active against BCR-ABL and SRC family kinases. We report the results of a Phase I dose-escalation study evaluating safety, tolerability, pharmacokinetics, and biomarkers of dasatinib in pts with advanced solid tumors. Methods: Pts with adequate hematologic, renal, cardiac and liver function received oral dasatinib once daily for 7 days per week. Three doses and schedules were examined: 90 mg BID; 140 mg QD; and 180 mg QD. Pharmacokinetics and pharmacodynamic biomarkers were collected on Days 1 and 26 of Cycle 1. Tissue biomarkers were assessed at screening. CT was performed at least every 8 weeks, and FDG-PET at weeks 4, and 8. Results: 26 pts [M=15, F=11] ECOG PS ≤ 2 with epithelial tumors (n=14) or other solid tumors (n=12) have been treated in escalating dose levels. Toxicity was generally mild; most patients came off study for progressive disease. DLTs of pleural effusions were seen in 3/9 subjects on the 180 mg cohort, 2 of whom had pre-existing effusions. Patients with pleural effusion have been excluded from future enrollment. The maximum tolerated dose has not been identified. There have been no objective responses on CT. Six patients have had stable disease with continued study treatment for 2–10 months. Conclusions: Dasatinib can be safely administered at doses of 140 and 180 mg QD. Clinical efficacy, pharmacokinetics, and correlative studies of tumor biopsy material and early FDG-PET results will be reported.

No significant financial relationships to disclose.

Phase 1 study of ARQ 197, a selective inhibitor of the c-Met RTK in patients with metastatic solid tumors reaches recommended phase 2 dose

3525

Background: ARQ 197 is a selective inhibitor of the c-Met receptor tyrosine kinase, an oncogene implicated in tumor invasiveness, metastasis, cancer cell proliferation, resistance to apoptosis, chemoresistance and angiogenesis. The c-Met RTK is a high-affinity receptor for hepatocyte growth factor (HGF). c-Met and HGF are dysregulated in a broad spectrum of cancers, thus inhibitors of c-Met could be promising targeted agents deserving clinical investigation. Methods: A phase 1 dose escalation study in metastatic pts who failed standard therapy was initiated to determine safety, tolerability, RP2D, pharmacokinetics, pharmacodynamics and preliminary antitumor activity of ARQ 197. Cycles consisted of twice-daily oral dosing of ARQ197 for two out of 3 weeks. Results: Thirty-eight pts were enrolled with data available for 36 pts (21M/15F; median age 61). Ten cohorts were assessed ranging from 10 to 360 mg/day. ARQ 197 was well tolerated and no DLT was observed. All treated pts achieved plasma drug concentrations significantly above the in vitro IC50. Doses through 70 mg b.i.d. revealed Cmax and AUC(0–12hr) increased linearly. There was no further increase in systemic exposure in pts treated with 90 through 180 mg b.i.d. There was notable inter-patient variability in Cmax and AUC(0–12hr), typical of oral dosing. The effects of cytochrome P450 polymorphism will be discussed. Adverse events (N=29) were generally mild with the most common being: fatigue (24 %), diarrhea (21%), and constipation (21%). Grade 3 or greater events possibly or probably related to ARQ 197 include: elevated ALP (3%), ALT (3%) and AST (3%). Of the 38 pts enrolled, 36 received at least one complete cycle of ARQ 197 with 33 evaluable for efficacy. Two pts achieved a PR (1 confirmed) and 19 had stable disease (SD) 21 10+ to 34+ weeks. Conclusions: Based on pharmacokinetic data, a RP2D for ARQ 197 was determined to be 120 mg b.i.d. Higher oral doses did not result in increased systemic systemic exposure to the drug. Eleven pts remain on study and continue to receive ARQ 197 treatment. A favorable adverse event profile and encouraging signs of anti-tumor activity was observed and continuous daily dosing of ARQ 197 is now being explored to better define clinical toxicity and efficacy.

[Table: see text]

Phase 2 dose multi-center, open-label study of ARQ 501, a checkpoint activator, in adult patients with persistent, recurrent or metastatic leiomyosarcoma (LMS)

20521

Background: ARQ 501 selectively induces apoptosis in cancer cells by inducing a rapid and sustained increase of the pro- apoptotic protein E2F-1. ARQ 501 has been studied in three phase 1 studies, demonstrating acceptable toxicity and encouraging signs of efficacy. A 54 y/o female with metastatic LMS who failed 7 previous therapies achieved a prolonged PR on ARQ 501 monotherapy. This was consistent with preclinical data, where induction of E2F-1 and corresponding efficacy in human leiomyosarcoma xenografts was observed. Methods: A phase 2 study in adult LMS patients (>3 prior systemic therapies) was initiated to assess ORR, TTP and further characterize the safety of ARQ 501. ORR included CR, PR and SD=4 mo. Four week cycles (ARQ 501 450mg/m2) were repeated until progression, unacceptable toxicity, or another discontinuation criterion. Results: 49 patients were enrolled and 45 received ARQ 501. Data is available for 43 patients (4M/39F, median age, 54). Of the 43, 10 did not reach a protocol defined tumor assessment (4 deaths, 5 PD and 1 lost to follow-up prior to week 8), 19 have been assessed for response per RECIST at eight weeks (7 SD of 8–28+ weeks, 1 PR, 11 PD) and 14 active patients yet to reach first tumor assessment. The most common AEs were: anemia (68%, 21%=G3), hyperbilirubinemia (35%, 6%=G3), fatigue (35%, 0%=G3), nausea (30%, 0%=G3), constipation (24%), hemolysis (21%, 6%=G3), dyspnea (21%), and vomiting (21%). One treatment related death was reported in a 47 y/o Asian male with severe hemolysis following a single infusion of ARQ 501 at 450 mg/m2. The pt was hospitalized, but severe hemolysis led to acute renal failure and the patient expired after 4 days. Conclusions: ARQ 501 was administered to 45 patients with advanced, recurrent or persistent leiomyosarcoma. Several patients have achieved some clinical benefit (1 PR, 3 prolonged SD), further analysis of efficacy data is warranted prior to additional clinical investigation.

No significant financial relationships to disclose.