Selective MCL-1 inhibitor ABBV-467 is efficacious in tumor models but is associated with cardiac troponin increases in patients

BACKGROUND

MCL-1 is a prosurvival B-cell lymphoma 2 family protein that plays a critical role in tumor maintenance and survival and can act as a resistance factor to multiple anticancer therapies. Herein, we describe the generation and characterization of the highly potent and selective MCL-1 inhibitor ABBV-467 and present findings from a first-in-human trial that included patients with relapsed/refractory multiple myeloma (NCT04178902).

METHODS

Binding of ABBV-467 to human MCL-1 was assessed in multiple cell lines. The ability of ABBV-467 to induce tumor growth inhibition was investigated in xenograft models of human multiple myeloma and acute myelogenous leukemia. The first-in-human study was a multicenter, open-label, dose-escalation study assessing safety, pharmacokinetics, and efficacy of ABBV-467 monotherapy.

RESULTS

Here we show that administration of ABBV-467 to MCL-1-dependent tumor cell lines triggers rapid and mechanism-based apoptosis. In vivo, intermittent dosing of ABBV-467 as monotherapy or in combination with venetoclax inhibits the growth of xenografts from human hematologic cancers. Results from a clinical trial evaluating ABBV-467 in patients with multiple myeloma based on these preclinical data indicate that treatment with ABBV-467 can result in disease control (seen in 1 patient), but may also cause increases in cardiac troponin levels in the plasma in some patients (seen in 4 of 8 patients), without other corresponding cardiac findings.

CONCLUSIONS

The selectivity of ABBV-467 suggests that treatment-induced troponin release is a consequence of MCL-1 inhibition and therefore may represent a class effect of MCL-1 inhibitors in human patients.

Predictive biomarkers for survival benefit with ramucirumab in urothelial cancer in the RANGE trial

The RANGE study (NCT02426125) evaluated ramucirumab (an anti-VEGFR2 monoclonal antibody) in patients with platinum-refractory advanced urothelial carcinoma (UC). Here, we use programmed cell death-ligand 1 (PD-L1) immunohistochemistry (IHC) and transcriptome analysis to evaluate the association of immune and angiogenesis pathways, and molecular subtypes, with overall survival (OS) in UC. Higher PD-L1 IHC and immune pathway scores, but not angiogenesis scores, are associated with greater ramucirumab OS benefit. Additionally, Basal subtypes, which have higher PD-L1 IHC and immune/angiogenesis pathway scores, show greater ramucirumab OS benefit compared to Luminal subtypes, which have relatively lower scores. Multivariable analysis suggests patients from East Asia as having lower immune/angiogenesis signature scores, which correlates with decreased ramucirumab OS benefit. Our data highlight the utility of multiple biomarkers including PD-L1, molecular subtype, and immune phenotype in identifying patients with UC who might derive the greatest benefit from treatment with ramucirumab.

A phase 1 study of LY3076226, a fibroblast growth factor receptor 3 (FGFR3) antibody-drug conjugate, in patients with advanced or metastatic cancer

Background We report a Phase 1 study of LY3076226, an antibody-drug conjugate composed of human IgG1 monoclonal antibody against the human FGFR3 attached with a cleavable linker to the maytansine derivative DM4 in patients with advanced or metastatic cancer. Methods This study was comprised of two parts: (A) dose escalation in patients with advanced or metastatic cancer and (B) dose expansion in patients with urothelial carcinoma with locally determined FGFR3 alterations. The dose range of LY3076226 tested was 0.2-5.0 mg/kg as an intravenous infusion on Day 1 of each 21-day cycle. The primary objective was to determine a recommended phase 2 dose (RP2D). Results Twenty-five patients were enrolled (Part A: 22, Part B: 3) and received ≥ 1 dose of LY3076226. No dose-limiting toxicities were reported. LY3076226 was generally well tolerated; most of the toxicities were Grade 1 or 2. Two patients experienced treatment-related Grade 3 toxicity (embolism and decreased platelet count). Four patients experienced serious adverse events (not treatment-related), all in Part A. Dose-proportional exposure was observed, with an estimated half-life of 2-7 days. No responses were seen with LY3076226 treatment. Stable disease persisting for > 6 months was observed in 1 patient receiving 3.2 mg/kg of LY3076226. Conclusion The study demonstrates acceptable safety and tolerability of LY3076226 up to the 5.0 mg/kg dose. Recruitment was stopped due to pipeline prioritization. Dose escalation of LY3076226 beyond 5.0 mg/kg in patients with advanced tumors may be possible. The trial was registered on August 19, 2015 under identifier NCT02529553 with ClinicalTrials.gov.

Efficacy and safety of first-line veliparib and carboplatin-paclitaxel in patients with HER2- advanced germline BRCA+ breast cancer: Subgroup analysis of a randomised clinical trial

BACKGROUND

Addition of veliparib to carboplatin-paclitaxel, with continuation of veliparib monotherapy if carboplatin-paclitaxel was discontinued, improved progression-free survival (PFS) in patients with germline BRCA-associated locally advanced/metastatic HER2- breast cancer and ≤2 lines of previous cytotoxic therapy for metastatic disease in BROCADE3. A pre-planned subgroup analysis evaluated efficacy and safety in patients without previous cytotoxic therapy for metastatic disease.

METHODS

Patients were randomised 2:1 to receive veliparib (120 mg orally BID) or placebo on days -2 to 5. Carboplatin (AUC 6) was administered on day 1, and paclitaxel (80 mg/m²) on days 1, 8 and 15 (21-day cycles). Patients discontinuing carboplatin-paclitaxel for reasons besides progression could continue veliparib/placebo monotherapy (300 mg BID, increasing to 400 mg BID if tolerated) until progression. The primary end-point was PFS assessed by investigator.

RESULTS

Of 509 patients in the intention-to-treat population (98.6% female; mean age 47, standard deviation 11), 413 (81%) had no previous cytotoxic therapy for metastatic disease (274, veliparib; 139, placebo). In the first-line subgroup, median PFS was 16.6 months (95% confidence interval [CI] 13.4-18.7) versus 13.1 months (95% CI 11.4-14.5) for the veliparib versus control groups (hazard ratio 0.70, 95% CI 0.54-0.89, P = .004). More patients were alive and progression-free at 2 years (36% versus 23.2%) and 3 years (27.9% versus 13.3%) in the veliparib versus control group. Adverse events unrelated to progression leading to study drug discontinuation occurred in 25 (9.1%) and 8 (5.8%) patients.

CONCLUSIONS

Veliparib with carboplatin-paclitaxel led to durable disease control among first-line patients, suggesting a benefit of this treatment approach in early lines.

CLINICAL TRIAL REGISTRATION

NCT02163694.

Post hoc analyses of GOG 9923: Does BRCA status affect toxicities?: An NRG oncology study

OBJECTIVE

To evaluate how women with epithelial ovarian cancer (EOC), dichotomized by BRCA status, tolerate intravenous (IV) or intraperitoneal (IP) chemotherapy given with veliparib and bevacizumab (bev) on a GOG phase I study (GOG 9923, NCT00989651).

METHODS

This is an unplanned, post hoc analysis of an IRB approved, multi-institutional, prospective study (GOG 9923). Clinical characteristics and toxicity data based on BRCA status were evaluated and descriptive statistics were used to summarize baseline patient characteristics and toxicities. The Kaplan Meier method was used to generate survival estimates.

RESULTS

Four hundred twenty-four patients were evaluable. Patients were treated with IV carboplatin, paclitaxel, and bev every 21 days (regimen 1), weekly IV paclitaxel with carboplatin and bev (regimen 2) or IV paclitaxel and bev with IP cisplatin (regimen 3). Bev was continued as maintenance in all arms. Within each of these regimens, veliparib was given either twice daily for the entirety of each cycle (continuous) or on days -2 to 5 (intermittent). Ten percent of patients treated on regimen 1, 12% on regimen 2, and 19.8% on regimen 3 had BRCA-associated tumors. Patients with BRCA-associated tumors, when compared to wild type, experienced similar rates of anemia, febrile neutropenia (, abdominal pain, colonic perforation, nausea, vomiting, and peripheral sensory neuropathy. Median progression free survival (PFS) was not significantly different between BRCA-associated and wild type cancers (HR 0.96, CI 0.65-1.42), though this study's primary aim was not to evaluate outcomes.

CONCLUSIONS

Germline BRCA mutations positively affect chemosensitivity in EOC, but whether differences in toxicities among BRCA-associated and BRCA wild type tumors existed was previously not reported. In this population with newly diagnosed ovarian cancer no differences in reported toxicity between the two groups was observed.

A phase I study of Aurora kinase A inhibitor LY3295668 erbumine as a single agent and in combination in patients with relapsed/refractory neuroblastoma

TPS10561

Background: Aurora kinase A (AurA) has been implicated in high-risk neuroblastoma, including roles stabilizing and increasing expression of MYCN protein. AurA impacts the function of MYCN in mediating transcription in a cell cycle dependent manner, suggesting that neuroblastoma and other MYC/MYCN-driven tumors may be sensitive to AurA inhibition. LY3295668 is a selective AurA inhibitor. The lack of AurB inhibitory activity is hypothesized to minimize on-target hematologic toxicity associated with AurB inhibition. The molecule’s selectivity is intended to allow for continuous dosing at exposures associated with > 90% target inhibition at trough. In an analysis of LY3295668 antiproliferative effects in 560 cancer cell lines, neuroblastoma was among the most sensitive histologies tested. This screen also separately evaluated genomic predictors of response to LY3295668, with MYC/ MYCN amplification identified as among the strongest predictors of sensitivity to this agent. LY3295668 is currently being evaluated in early phase adult trials. The current trial (J10-MC-JZHD) was uniquely designed to hasten time to first-in-child oncology development for a rare unmet need of relapsed/refractory neuroblastoma patients. Methods: Study J1O-MC-JZHD (NCT04106219) is a multicenter, dual collaboration (NANT and ITCC), randomized, open-label, Phase 1 study of oral LY3295668 in children with relapsed/refractory neuroblastoma. A rolling 6 design will be followed for dose escalation in both a monotherapy cohort and a combination cohort testing LY3295668 together with cyclophosphamide and topotecan. The starting monotherapy dose will be equivalent to 80% of the adult maximum tolerated dose. Key eligibility criteria include recurrent/refractory neuroblastoma not amenable to curative treatment, age 2-21 years, mandatory archival tissue submission, ability to swallow capsules, and adequate hematologic and organ function. LY3295668 is administered in capsule form orally BID continuously. Primary objectives include assessments of safety and tolerability of study drug to identify RP2D as monotherapy and combination, and assess antitumor activity. Secondary objectives include assessment of the pharmacokinetic profile as monotherapy and in combination, and assessment of the relationship between study drug exposure and efficacy. Following determination of the RP2Ds, an expansion phase will randomize patients to monotherapy or to the combination arm. Enrollment began 16 Dec 2019 and is ongoing. Clinical trial information: NCT04106219.

Ramucirumab plus docetaxel versus placebo plus docetaxel in patients with locally advanced or metastatic urothelial carcinoma after platinum-based therapy (RANGE): overall survival and updated results of a randomised, double-blind, phase 3 trial

BACKGROUND

Ramucirumab-an IgG1 vascular endothelial growth factor receptor 2 antagonist-plus docetaxel was previously reported to improve progression-free survival in platinum-refractory, advanced urothelial carcinoma. Here, we report the secondary endpoint of overall survival results for the RANGE trial.

METHODS

We did a randomised, double-blind, phase 3 trial in patients with advanced or metastatic urothelial carcinoma who progressed during or after platinum-based chemotherapy. Patients were enrolled from 124 investigative sites (hospitals, clinics, and academic centres) in 23 countries. Previous treatment with one immune checkpoint inhibitor was permitted. Patients were randomly assigned (1:1) using an interactive web response system to receive intravenous ramucirumab 10 mg/kg or placebo 10 mg/kg volume equivalent followed by intravenous docetaxel 75 mg/m2 (60 mg/m2 in Korea, Taiwan, and Japan) on day 1 of a 21-day cycle. Treatment continued until disease progression, unacceptable toxicity, or other discontinuation criteria were met. Randomisation was stratified by geographical region, Eastern Cooperative Oncology Group performance status at baseline, and visceral metastasis. Progression-free survival (the primary endpoint) and overall survival (a key secondary endpoint) were assessed in the intention-to-treat population. The study is registered with ClinicalTrials.gov, NCT02426125; patient enrolment is complete and the last patient on treatment is being followed up for safety issues.

FINDINGS

Between July 20, 2015, and April 4, 2017, 530 patients were randomly allocated to ramucirumab plus docetaxel (n=263) or placebo plus docetaxel (n=267) and comprised the intention-to-treat population. At database lock (March 21, 2018) for the final overall survival analysis, median follow-up was 7·4 months (IQR 3·5-13·9). In our sensitivity analysis of investigator-assessed progression-free survival at the overall survival database lock, median progression-free survival remained significantly improved with ramucirumab compared with placebo (4·1 months [95% CI 3·3-4·8] vs 2·8 months [2·6-2·9]; HR 0·696 [95% CI 0·573-0·845]; p=0·0002). Median overall survival was 9·4 months (95% CI 7·9-11·4) in the ramucirumab group versus 7·9 months (7·0-9·3) in the placebo group (stratified HR 0·887 [95% CI 0·724-1·086]; p=0·25). Grade 3 or worse treatment-related treatment-emergent adverse events in 5% or more of patients and with an incidence more than 2% higher with ramucirumab than with placebo were febrile neutropenia (24 [9%] of 258 patients in the ramucirumab group vs 16 [6%] of 265 patients in the placebo group) and neutropenia (17 [7%] of 258 vs six [2%] of 265). Serious adverse events were similar between groups (112 [43%] of 258 patients in the ramucirumab group vs 107 [40%] of 265 patients in the placebo group). Adverse events related to study treatment and leading to death occurred in eight (3%) patients in the ramucirumab group versus five (2%) patients in the placebo group.

INTERPRETATION

Additional follow-up supports that ramucirumab plus docetaxel significantly improves progression-free survival, without a significant improvement in overall survival, for patients with platinum-refractory advanced urothelial carcinoma. Clinically meaningful benefit might be restricted in an unselected population.

FUNDING

Eli Lilly and Company.

A phase I study of intravenous or intraperitoneal platinum based chemotherapy in combination with veliparib and bevacizumab in newly diagnosed ovarian, primary peritoneal and fallopian tube cancer

BACKGROUND

Improvements in disease free survival for epithelial ovarian, peritoneal or fallopian tube cancer (EOC) will only come with improved primary therapy. Incorporation of poly-ADP-ribose inhibitors (PARPi) in the frontline setting may represent one strategy. This study sought to determine the maximum tolerated and feasible doses of the PARPi veliparib in combination with chemotherapy for EOC.

METHODS

A phase I, 3 + 3 dose escalation evaluated dose-limiting toxicities (DLTs) in cycles 1-2. Once <2/6 patients experienced a DLT, that dose level expanded to evaluate feasibility over 4 cycles. This study opened 10/2009 and closed 8/2016. Eligible patients had untreated, stage II-IV EOC. Veliparib was added either continuous (day 1-21) or intermittent (day - 2 to 5) during 6 cycles of chemotherapy. Three chemotherapy backbones were evaluated (2 intravenous (q3week and weekly) and 1 intraperitoneal (IP)) all inclusive of bevacizumab with and as maintenance to 22 cycles.

FINDINGS

Dose evaluations for 424 treated patients were available. Regimen 1 (q3 week), continuous (Reg1c) the maximum tolerated dose (MTD) was 250 mg veliparib BID and feasible dose was 150 mg BID. For regimen 1, intermittent (Reg1i) the MTD and feasible dose were 400 and 250 mg BID. For Reg2c (weekly paclitaxel) the MTD and feasible dose were 150 mg BID. For Reg2i the MTD and feasible dose were 250 and 150 mg BID. For Reg3c (IP) the MTD and feasible dose were 150 mg BID and for Reg3i (IP), the MTD and feasible dose were 400 mg and 300 mg BID.

INTERPRETATION

The feasible dose for Reg1c, 2c, 2i and 3c was 150 mg po BID. For Reg1i and 3i the dose was pushed to 250 and 300 mg po BID respectively. There is no apparent difference in efficacy between continuous and intermittent dosing indicating that the higher doses achieved in intermittent dosing may not be needed. (NCT00989651).

FUNDING

National Cancer Institute.

A phase I study of veliparib incorporated into front-line platinum based cheotherpy and bevacizumab in epithelial ovarian cancer (NCT00989651): A GOG/nrg trial

5523

Background: Veliparib, a poly-(ADP-ribose)-polymerase inhibitor, increases anti-tumor activity when combined with platinum chemotherapy and has monotherapy activity in BRCA deficient tumors. This study was done to determine the recommended phase II dose (RP2D) of veliparib in combination with front line treatment for epithelial ovarian cancer (EOC). Methods: Eligible patients had newly diagnosed, stage II-IV EOC. Six regimens were evaluated, 3 variations of chemo delivery with either continuous (D1-21) or intermittent (days-2-5) veliparib BID. Chemo included 1: IV q3week carboplatin (C) (AUC 6) and paclitaxel(T) (175mg/m2); 2, IV q3week C (AUC 6) and weekly T(80mg/m2); and 3, IV T (135mg/m2, day 1), IP cisplatin (75mg/m2, day 1 or 2) and IP T (60mg/m2, day 8). Bevacizumab 15mg/kg started cycle 2 and continued as monotherapy cycles 7-22. A 3+3 dose escalation design evaluated dose-limiting toxicities (DLTs) in cycles 1 and 2. Once < 2/6 patients experienced a DLT, that dose level was expanded to evaluate feasibility over 4 cycles. Results: The study accrued 424 treated patients. For regimen 1, continuous (Reg1c) the maximum tolerated dose (MTD) was 250mg veliparib BID but the feasible dose was found to be 150mg BID. For regimen 1, intermittent (Reg1i) the MTD and feasible dose were 400 and 250mg BID respectively. For Reg2c the MTD and feasible dose were the same at 150mg BID. For Reg2i the MTD and feasible dose were 250 and 150mg BID respectively. For Reg3c the MTD and feasible dose are both 150mg BID and for Reg3i, the MTD was 400mg BID and the feasible dose felt to be 300mg BID. Median PFS by residual disease and BRCA status is: (Positive residual disease) 14.6, 19.1 and 16.9 months for BRCA+, BRCAwt and BRCA ukn respectively. For no gross residual disease the PFS is NR, 34.2 and 24.5 months respectively. Conclusions: Given the difficulty with toxicity not defined as a DLT, the RP2D for all regimens is veliparib 150mg BID. This data informed the dose that moved into the phase III trial GOG 3005/Velia: NCT02470585. Velia also incorporated maintenance veliparib instead of maintenance bevacizumab among all high grade serous patients (BRCA+ and wt). These results will determine utilization of veliparib in this space. Clinical trial information: NCT00989651.

A randomized, double-blind, placebo-controlled phase Ib/II study of ralimetinib, a p38 MAPK inhibitor, plus gemcitabine (G) and carboplatin (C) versus GC for women with recurrent platinum-sensitive ovarian cancer

5537

Background: p38 mitogen-activated protein kinase (MAPK) regulates cytokine production in the tumor microenvironment and enables therapeutic resistance of cancer cells. Ralimetinib (R) is a selective small-molecule inhibitor of p38α and p38β MAPKs. Methods: Main inclusion criteria: ≥18 y; recurrent platinum-sensitive epithelial ovarian, fallopian tube, or primary peritoneal, cancer after first-line treatment. Phase (Ph)1b was to determine the recommended Ph2 dose (RP2D) of R administered 12-hourly (Q12H) on Days 1-10 (21-day cycle [Q21D]) in combination with gemcitabine (G: 1000 mg/m2 on Days 3 and 10) and carboplatin (C: AUC 4 on Day 3) for 6 cycles. In Ph2, patients (pts) were randomized double-blind, 1:1 to RP2D R+GC or placebo (P)+GC, for 6 cycles, followed by R 300 mg Q12H or P on Days 1-14, Q28D until disease progression. The stratified log-rank test compared progression-free survival (PFS; primary endpoint) between treatment groups in Ph2, at a 1-sided α level of 0.2. ClinicalTrials.gov, NCT01663857. Results: 118 pts received ≥1 dose of R or P (safety population); 8 in Ph1b and 110 in Ph2 (R+GC N = 58; P+GC N = 52). The RP2D for R in combination with GC was 200 mg Q12H. The study met its primary objective (median PFS: R+GC 10.3 mo vs P+GC 7.9 mo; HR = 0.773, 2-sided p = 0.246). The secondary objectives of median overall survival (R+GC 29.2 mo vs P+GC 25.1 mo; HR = 0.827, p = 0.469) or overall response rate (R+GC 46.6% vs P+GC 46.2%; p = 0.967) were not statistically significant, and 32.4% vs 25.0% of pts had normalized CA125 at the end of cycle 6. Most pts (safety population) experienced ≥1 Grade 3/4 treatment-emergent adverse event (TEAE: R+GC 63/66 [95.5%]; P+GC 48/52 [92.3%]). Decreased neutrophil count (60.6% vs 76.9%), platelet count (43.9% vs 38.5%), and white blood cell count, (30.3% vs 26.9%), anemia (22.7% vs 25.0%), and increased alanine aminotransferase (ALT) (19.7% vs 3.8%) were the Grade 3/4 TEAEs in ≥10% of pts in the R+GC and P+GC arms, respectively. Conclusions: Addition of ralimetinib to GC resulted in modest improvements in PFS. Grade 3/4 elevated ALT was more common in the ralimetinib arm. Clinical trial information: NCT01663857.

Ramucirumab (RAM) exposure-response (ER) relationship in RANGE: A randomized phase III trial of RAM plus docetaxel (DOC) versus placebo (P) plus DOC in advanced platinum-refractory urothelial carcinoma (UC) patients (pts)

353

Background: Recent RANGE results showed significant improvement in PFS, a non-significant positive trend in OS, increased ORR and acceptable safety with RAM+DOC vs P+DOC in UC pts (Petrylak et al. Lancet 2017; Petrylak et al. ESMO 2018, abstr 865PD). RAM ER-OS relationships in RANGE are reported here. Methods: Pts received RAM (10 mg/kg) + DOC or P + DOC (Day 1 of a 21 day cycle) until discontinuation criteria were met. Population pharmacokinetic analysis predicted RAM minimum concentrations after first dose (RAM Cmin, 1). Multivariate Cox regression & matched case control (MCC) analyses using exposure treated as a continuous covariate, or grouped as quartiles, evaluated the ER-OS relationship. Results: Several poor prognostic factors, including Bellmunt risk factors, appeared to be more frequent in the lower exposure quartiles, suggesting a possible disease-PK interaction. Increasing RAM exposure as a continuous covariate in an ER population of n=246 pts significantly ( p=0.01) associated with improvements in OS. Higher exposure quartiles trended toward longer survival & smaller HRs compared to P (Table, Q1=lowest). Conclusions: OS and ORR benefits favored Q4, a group which was associated with more favorable prognostic features and higher exposure. The observed disease-PK interaction may confound the interpretation of the ER results and warrants further exploration. Clinical trial information: NCT02426125. [Table: see text]

A phase I, open-label, two-stage study to investigate the safety, tolerability, pharmacokinetics, and pharmacodynamics of the oral AKT inhibitor GSK2141795 in patients with solid tumors

Background We sought to determine the recommended phase II dose (RP2D) and schedule of GSK2141795, an oral pan-AKT kinase inhibitor. Patients and Methods Patients with solid tumors were enrolled in the dose-escalation phase. Pharmacokinetic (PK) analysis after a single dose (Cycle 0) informed dose escalation using accelerated dose titration. Once one grade 2 toxicity or dose-limiting toxicity was observed in Cycle 1, the accelerated dose titration was terminated and a 3 + 3 dose escalation was started. Continuous daily dosing was evaluated along with two intermittent regimens (7 days on/7 days off and 3 times per week). In the expansion phase at RP2D, patients with endometrial or prostate cancer, as well as those with select tumor types with a PIK3CA mutation, AKT mutation or PTEN loss, were enrolled. Patients were evaluated for adverse events (AEs), PK parameters, blood glucose and insulin levels, and tumor response. Results The RP2D of GSK2141795 for once-daily dosing is 75 mg. The most common (>10%) treatment-related AEs included diarrhea, fatigue, vomiting, and decreased appetite. Most AEs were low grade. The frequency of hyperglycemia increased with dose; however, at the RP2D, grade 3 hyperglycemia was only reported in 4% of patients and no grade 4 events were observed. PK characteristics were favorable, with a prolonged half-life and low peak-to-trough ratio. There were two partial responses at the RP2D in patients with either a PIK3CA mutation or PTEN loss. Conclusion GSK2141795 was safe and well-tolerated, with clinical activity seen as monotherapy at the RP2D of 75 mg daily. NCT00920257.

Vascular and tumor cell expression of VEGFR2 and molecular subtyping: An innovative biomarker approach in bladder cancer

497

Background: Treatment approaches combining anti-angiogenic therapy with chemotherapy have shown promising clinical results in metastatic bladder cancer (BC). In order to interrogate the potential clinico-pathologic and molecular basis of these findings, we evaluated VEGFR2, vascular density and molecular subtyping in a series of BC patients. Methods: A custom-TMA with primary BC tissues from 117 patients (mean age 71 yrs; range 38-99 yrs; M:F = 83:34) treated at a single institution, was stained and scored (0-3) for CD34 (vascular density) and for VEGFR2 on tumor vessels and cells. CK5/6 and GATA3 IHC was scored by a pathologist to identify main molecular classes of BC. The association between clinico-pathologic variables, VEGFR2, CD34 and molecular subtypes was analyzed by Fisher’s exact test and ANOVA. Univariate and multivariate Cox proportional models were used for survival analysis. Results: Of 112 analyzable BC tissues, 41% were muscle-invasive (MIBC) vs. 56% non-muscle invasive (NMIBC) and 3% undetermined. Compared to NMIBC patients those with MIBC had shorter overall survival (p < 0.001). The main molecular subtypes included basal (11%), mixed baso-luminal (28%) and luminal (61%). Compared to luminal and baso-luminal subtypes, the majority of basal BCs were muscle invasive (p = 0.036). VEGFR2 expression was higher in tumor vessels but variable in tumor cells. 74% of BCs showed high-medium levels of VEGFR2 (scores 3-2) in tumor vessels and 88% had high-medium levels of tumor vascular density. Within basal, luminal and baso-luminal subtypes, 58%, 78% and 71% had high-medium levels of vascular VEGFR2 (p = 0.52), while 83%, 91% and 82% had high-medium levels of tumor vascular density (p = 0.08). Survival analyses showed increasing patient age, higher stage and lower VEGFR2 levels as independent predictors of shorter survival. Conclusions: Given the observed complexity of BC regarding VEGFR2 expression and vascular density across molecular subtypes, further investigation is warranted to understand how the frequent expression of VEGFR2 on tumor vasculature and variable expression in tumor cells relates to the efficacy of anti-angiogenic agents across these subtypes in bladder cancer.

Quality-of-life (QoL) in RANGE: A phase 3 study of ramucirumab (RAM) plus docetaxel (DOC) versus placebo (P) plus DOC in platinum-refractory locally advanced or metastatic urothelial carcinoma (UC)

419

Background: RAM + DOC in RANGE (NCT02426125) improved progression free survival (hazard ratio [HR] = 0.757) with a higher objective response rate (24.5% vs 14%) and an acceptable safety profile (Petrylak, et al Lancet 2017). QoL was a secondary objective. Methods: Patients (pts) whose UC progressed following platinum-based therapy were randomized to receive RAM (10 mg/kg) + DOC (75 mg/m2) or P + DOC on Day 1 of a 21-day cycle. Treatment continued until disease progression or unacceptable toxicity with a maximum of 10 cycles for DOC. Pts completed the EORTC QLQ-C30 (v3) prior to each cycle & at the 30-day follow up visit. QoL scales were analyzed for: 1) rates of improved/stable scores (compared with Fisher’s exact test) & 2) time to sustained deterioration (TtD), defined as randomization to first worsening with no subsequent non-worsened assessment (compared with unstratified log-rank test). A ≥10 point change (on 100-point scale) was deemed clinically meaningful. Results: 530 pts were randomized. 254/263 (97%) RAM-DOC & 260/267 (97%) P-DOC pts provided baseline (BL) QoL data & ≥85% for post-BL, on-therapy assessments. Median number of cycles was 4 for RAM-DOC & 3 for P-DOC. Mean BL scores were similar between arms & indicated greatest impairment for global QoL, fatigue, pain, & insomnia. For all scales, rates of improved/stable scores were not different, except for pain at Cycles 4 & 7 where rates were higher for RAM-DOC (p < 0.05). Relative to other QoL scales, pain generally had highest rates of improved scores in both arms (14-25% for RAM-DOC & 8-24% for P-DOC for Cycles 1-4). In a post hoc analysis, Cycles 1-4 rates of improved pain scores were 31-32% for RAM-DOC & 14-26% for P-DOC in tumor responders, but 17-29% for RAM-DOC & 16-28% for P-DOC in pts with stable disease. For TtD, 14/15 QoL scales had HRs < 1, indicating similar or numerically longer TtD in QoL for RAM-DOC (HRs 0.67- 1.06; all 95% confidence intervals included 1). Conclusions: The addition of RAM to DOC for platinum-refractory UC pts did not adversely impact QoL relative to P-DOC. Trends in improved TtD and improved rates of pain associated with tumor response favored RAM-DOC. Clinical trial information: NCT02426125.

Docetaxel with or without ramucirumab after immune checkpoint inhibition in platinum-refractory metastatic urothelial carcinoma (mUC): Prespecified subgroup analysis from the phase 3 RANGE trial

434

Background: Immune checkpoint inhibitors (ICI) targeting PD-1/PD-L1 have shown objective response rates (ORR) of 15-21% in PD-L1 unselected patients (pts) with platinum-refractory mUC. Overall results of RANGE, a randomized, double-blinded phase 3 trial comparing ramucirumab and docetaxel (R+D) to placebo and docetaxel (P+D) in pts with platinum-refractory mUC demonstrated an ORR of 24.5% to R+D and a statistically significant improvement in progression free survival (PFS; median 4.07 vs 2.76 mo; HR 0.757). Here we present a pre-specified subgroup analysis of pts who received a prior ICI. Methods: RANGE enrolled pts with progressive mUC during or after platinum-based chemotherapy. Additional prior treatment with one ICI was permitted. Pts were randomized (1:1) to receive D 75 mg/m2 up to 10 cycles with R 10 mg/kg or P on day 1 of a 21-day cycle until disease progression or other discontinuation criteria. Primary endpoint, investigator-assessed PFS, was analyzed in the first 437 randomized pts. Secondary endpoints included overall survival, objective response, and safety. Radiographic assessment occurred every 6 weeks. Results: Thirty three of the 437 pts (8%) in the PFS population received a prior ICI. The majority (91%) received the ICI immediately following platinum and immediately prior to RANGE. Most pts received atezolizumab (55%) or pembrolizumab (36%); ORR to prior ICI was 6% and the majority (67%) had progressive disease as best response. Median duration of the ICI was 3.5 mo (IQR 1.6-5.2). Disease sites at entry onto RANGE included lymph node (79%), lung (48%), liver (39%) and bone (18%). At data cutoff, responses were achieved by 5/14 (35.7%) on R+D, compared to 2/19 (10.5%) on P+D. Responses to R+D were independent of disease site. Of pts with liver metastases, 3/8 responded to R+D compared to 0/5 on P+D. Overall, median PFS was 5.29 mo on R+D and 2.76 mo on P+D (HR 0.920). The frequency of grade ≥3 adverse events was similar between arms. Conclusions: Acknowledging limitations of sample size, R+D showed higher ORR than P+D in pts who had progressed on platinum and ICI therapy, including those with liver metastases. Clinical trial information: NCT02426125.

A phase I trial of paclitaxel, cisplatin, and veliparib in the treatment of persistent or recurrent carcinoma of the cervix: an NRG Oncology Study (NCT#01281852)

Background

Preclinical studies demonstrate poly(ADP-ribose) polymerase (PARP) inhibition augments apoptotic response and sensitizes cervical cancer cells to the effects of cisplatin. Given the use of cisplatin and paclitaxel as first-line treatment for persistent or recurrent cervical cancer, we aimed to estimate the maximum tolerated dose (MTD) of the PARP inhibitor veliparib when added to chemotherapy.

Patients and methods

Women with persistent or recurrent cervical carcinoma not amenable to curative therapy were enrolled. Patients had to have received concurrent chemotherapy and radiation as well as possible consolidation chemotherapy; have adequate organ function. The trial utilized a standard 3 + 3 phase I dose escalation with patients receiving paclitaxel 175 mg/m2 on day 1, cisplatin 50 mg/m2 on day 2, and escalating doses of veliparib ranging from 50 to 400 mg orally two times daily on days 1-7. Cycles occurred every 21 days until progression. Dose-limiting toxicities (DLTs) were assessed at first cycle. Fanconi anemia complementation group D2 (FANCD2) foci was evaluated in tissue specimens as a biomarker of response.

Results

Thirty-four patients received treatment. DLTs (n = 1) were a grade 4 dyspnea, a grade 3 neutropenia lasting ≥3 weeks, and febrile neutropenia. At 400 mg dose level (DL), one of the six patients had a DLT, so the MTD was not reached. Across DLs, the objective response rate (RR) for 29 patients with measurable disease was 34% [95% confidence interval (CI), 20%-53%]; at 400 mg DL, the RR was 60% (n = 3/5; 95% CI, 23%-88%). Median progression-free survival was 6.2 months (95% CI, 2.9-10.1), and overall survival was 14.5 months (95% CI, 8.2-19.4). FANCD2 foci was negative or heterogeneous in 31% of patients and present in 69%. Objective RR were not associated with FANCD2 foci (P = 0.53).

Conclusions

Combining veliparib with paclitaxel and cisplatin as first-line treatment for persistent or recurrent cervical cancer patients is safe and feasible.

Clinical trial information

NCT01281852.

Ramucirumab plus docetaxel versus placebo plus docetaxel in patients with locally advanced or metastatic urothelial carcinoma after platinum-based therapy (RANGE): a randomised, double-blind, phase 3 trial

BACKGROUND

Few treatments with a distinct mechanism of action are available for patients with platinum-refractory advanced or metastatic urothelial carcinoma. We assessed the efficacy and safety of treatment with docetaxel plus either ramucirumab-a human IgG1 VEGFR-2 antagonist-or placebo in this patient population.

METHODS

We did a randomised, double-blind, phase 3 trial in patients with advanced or metastatic urothelial carcinoma who progressed during or after platinum-based chemotherapy. Patients were enrolled from 124 sites in 23 countries. Previous treatment with one immune-checkpoint inhibitor was permitted. Patients were randomised (1:1) using an interactive web response system to receive intravenous docetaxel 75 mg/m2 plus either intravenous ramucirumab 10 mg/kg or matching placebo on day 1 of repeating 21-day cycles, until disease progression or other discontinuation criteria were met. The primary endpoint was investigator-assessed progression-free survival, analysed by intention-to-treat in the first 437 randomised patients. This study is registered with ClinicalTrials.gov, number NCT02426125.

FINDINGS

Between July, 2015, and April, 2017, 530 patients were randomly allocated either ramucirumab plus docetaxel (n=263) or placebo plus docetaxel (n=267). Progression-free survival was prolonged significantly in patients allocated ramucirumab plus docetaxel versus placebo plus docetaxel (median 4·07 months [95% CI 2·96-4·47] vs 2·76 months [2·60-2·96]; hazard ratio [HR] 0·757, 95% CI 0·607-0·943; p=0·0118). A blinded independent central analysis was consistent with these results. An objective response was achieved by 53 (24·5%, 95% CI 18·8-30·3) of 216 patients allocated ramucirumab and 31 (14·0%, 9·4-18·6) of 221 assigned placebo. The most frequently reported treatment-emergent adverse events, regardless of causality, in either treatment group (any grade) were fatigue, alopecia, diarrhoea, decreased appetite, and nausea. These events occurred predominantly at grade 1-2 severity. The frequency of grade 3 or worse adverse events was similar for patients allocated ramucirumab and placebo (156 [60%] of 258 vs 163 [62%] of 265 had an adverse event), with no unexpected toxic effects. 63 (24%) of 258 patients allocated ramucirumab and 54 (20%) of 265 assigned placebo had a serious adverse event that was judged by the investigator to be related to treatment. 38 (15%) of 258 patients allocated ramucirumab and 43 (16%) of 265 assigned placebo died on treatment or within 30 days of discontinuation, of which eight (3%) and five (2%) deaths were deemed related to treatment by the investigator. Sepsis was the most common adverse event leading to death on treatment (four [2%] vs none [0%]). One fatal event of neutropenic sepsis was reported in a patient allocated ramucirumab.

INTERPRETATION

To the best of our knowledge, ramucirumab plus docetaxel is the first regimen in a phase 3 study to show superior progression-free survival over chemotherapy in patients with platinum-refractory advanced urothelial carcinoma. These data validate inhibition of VEGFR-2 signalling as a potential new therapeutic treatment option for patients with urothelial carcinoma.

FUNDING

Eli Lilly and Company.

Rucaparib in relapsed, platinum-sensitive high-grade ovarian carcinoma (ARIEL2 Part 1): an international, multicentre, open-label, phase 2 trial

BACKGROUND

Poly(ADP-ribose) polymerase (PARP) inhibitors have activity in ovarian carcinomas with homologous recombination deficiency. Along with BRCA1 and BRCA2 (BRCA) mutations genomic loss of heterozygosity (LOH) might also represent homologous recombination deficiency. In ARIEL2, we assessed the ability of tumour genomic LOH, quantified with a next-generation sequencing assay, to predict response to rucaparib, an oral PARP inhibitor.

METHODS

ARIEL2 is an international, multicentre, two-part, phase 2, open-label study done at 49 hospitals and cancer centres in Australia, Canada, France, Spain, the UK, and the USA. In ARIEL2 Part 1, patients with recurrent, platinum-sensitive, high-grade ovarian carcinoma were classified into one of three predefined homologous recombination deficiency subgroups on the basis of tumour mutational analysis: BRCA mutant (deleterious germline or somatic), BRCA wild-type and LOH high (LOH high group), or BRCA wild-type and LOH low (LOH low group). We prespecified a cutoff of 14% or more genomic LOH for LOH high. Patients began treatment with oral rucaparib at 600 mg twice per day for continuous 28 day cycles until disease progression or any other reason for discontinuation. The primary endpoint was progression-free survival. All patients treated with at least one dose of rucaparib were included in the safety analyses and all treated patients who were classified were included in the primary endpoint analysis. This trial is registered with ClinicalTrials.gov, number NCT01891344. Enrolment into ARIEL2 Part 1 is complete, although an extension (Part 2) is ongoing.

FINDINGS

256 patients were screened and 206 were enrolled between Oct 30, 2013, and Dec 19, 2014. At the data cutoff date (Jan 18, 2016), 204 patients had received rucaparib, with 28 patients remaining in the study. 192 patients could be classified into one of the three predefined homologous recombination deficiency subgroups: BRCA mutant (n=40), LOH high (n=82), or LOH low (n=70). Tumours from 12 patients were established as BRCA wild-type, but could not be classified for LOH, because of insufficient neoplastic nuclei in the sample. The median duration of treatment for the 204 patients was 5·7 months (IQR 2·8-10·1). 24 patients in the BRCA mutant subgroup, 56 patients in the LOH high subgroup, and 59 patients in the LOH low subgroup had disease progression or died. Median progression-free survival after rucaparib treatment was 12·8 months (95% CI 9·0-14·7) in the BRCA mutant subgroup, 5·7 months (5·3-7·6) in the LOH high subgroup, and 5·2 months (3·6-5·5) in the LOH low subgroup. Progression-free survival was significantly longer in the BRCA mutant (hazard ratio 0·27, 95% CI 0·16-0·44, p<0·0001) and LOH high (0·62, 0·42-0·90, p=0·011) subgroups compared with the LOH low subgroup. The most common grade 3 or worse treatment-emergent adverse events were anaemia or decreased haemoglobin (45 [22%] patients), and elevations in alanine aminotransferase or aspartate aminotransferase (25 [12%]). Common serious adverse events included small intestinal obstruction (10 [5%] of 204 patients), malignant neoplasm progression (10 [5%]), and anaemia (nine [4%]). Three patients died during the study (two because of disease progression and one because of sepsis and disease progression). No treatment-related deaths occurred.

INTERPRETATION

In patients with BRCA mutant or BRCA wild-type and LOH high platinum-sensitive ovarian carcinomas treated with rucaparib, progression-free survival was longer than in patients with BRCA wild-type LOH low carcinomas. Our results suggest that assessment of tumour LOH can be used to identify patients with BRCA wild-type platinum-sensitive ovarian cancers who might benefit from rucaparib. These results extend the potential usefulness of PARP inhibitors in the treatment setting beyond BRCA mutant tumours.

FUNDING

Clovis Oncology, US Department of Defense Ovarian Cancer Research Program, Stand Up To Cancer-Ovarian Cancer Research Fund Alliance-National Ovarian Cancer Coalition Dream Team Translational Research Grant, and V Foundation Translational Award.

Integrative Development of a TLR8 Agonist for Ovarian Cancer Chemoimmunotherapy

Purpose: Immunotherapy is an emerging paradigm for the treatment of cancer, but the potential efficacy of many drugs cannot be sufficiently tested in the mouse. We sought to develop a rational combination of motolimod-a novel Toll-like receptor 8 (TLR8) agonist that stimulates robust innate immune responses in humans but diminished responses in mice-with pegylated liposomal doxorubicin (PLD), a chemotherapeutic that induces immunogenic cell death.Experimental Design: We followed an integrative pharmacologic approach including healthy human volunteers, non-human primates, NSG-HIS ("humanized immune system") mice reconstituted with human CD34⁺ cells, and patients with cancer to test the effects of motolimod and to assess the combination of motolimod with PLD for the treatment of ovarian cancer.Results: The pharmacodynamic effects of motolimod monotherapy in NSG-HIS mice closely mimicked those in non-human primates and healthy human subjects, whereas the effects of the motolimod/PLD combination in tumor-bearing NSG-HIS mice closely mimicked those in patients with ovarian cancer treated in a phase Ib trial (NCT01294293). The NSG-HIS mouse helped elucidate the mechanism of action of the combination and revealed a positive interaction between the two drugs in vivo The combination produced no dose-limiting toxicities in patients with ovarian cancer. Two subjects (15%) had complete responses and 7 subjects (53%) had disease stabilization. A phase II study was consequently initiated.Conclusions: These results are the first to demonstrate the value of pharmacologic approaches integrating the NSG-HIS mouse, non-human primates, and patients with cancer for the development of novel immunomodulatory anticancer agents with human specificity. Clin Cancer Res; 23(8); 1955-66. ©2016 AACR.

First-in-Human Study of PF-05212384 (PKI-587), a Small-Molecule, Intravenous, Dual Inhibitor of PI3K and mTOR in Patients with Advanced Cancer

PURPOSE

To evaluate safety (primary endpoint), tolerability, pharmacokinetics, pharmacodynamic profile, and preliminary activity of the intravenous, pan-class I isoform PI3K/mTOR inhibitor PF-05212384 in patients with advanced solid tumors.

EXPERIMENTAL DESIGN

Part 1 of this open-label phase I study was designed to estimate the maximum-tolerated dose (MTD) in patients with nonselected solid tumors, using a modified continual reassessment method to guide dose escalation. Objectives of part 2 were MTD confirmation and assessment of preliminary activity in patients with selected tumor types and PI3K pathway dysregulation.

RESULTS

Seventy-seven of the 78 enrolled patients received treatment. The MTD for PF-05212384, administered intravenously once weekly, was estimated to be 154 mg. The most common treatment-related adverse events (AE) were mucosal inflammation/stomatitis (58.4%), nausea (42.9%), hyperglycemia (26%), decreased appetite (24.7%), fatigue (24.7%), and vomiting (24.7%). The majority of patients treated at the MTD experienced only grade 1 treatment-related AEs. Grade 3 treatment-related AEs occurred in 23.8% of patients at the MTD. No treatment-related grade 4-5 AEs were reported at any dose level. Antitumor activity was noted in this heavily pretreated patient population, with two partial responses (PR) and an unconfirmed PR. Eight patients had long-lasting stable disease (>6 months). Pharmacokinetic analyses showed a biphasic concentration-time profile for PF-05212384 (half-life, 30-37 hours after multiple dosing). PF-05212384 inhibited downstream effectors of the PI3K pathway in paired tumor biopsies.

CONCLUSIONS

These findings demonstrate the manageable safety profile and antitumor activity of the PI3K/mTOR inhibitor PF-05212384, supporting further clinical development for patients with advanced solid malignancies.

VTX-2337, a TLR8 agonist, plus chemotherapy in recurrent ovarian cancer: Preclinical and phase I data by the Gynecologic Oncology Group

3077

Background: Given the absence of clear molecular drivers in high-grade serous ovarian cancer, targeting the tumor micro-environment with immunotherapy is an emerging approach. VTX-2337 is a potent, small molecule agonist of TLR8 which stimulates the innate immune response, and was previously evaluated as a single agent in cancer patients. We report data combining VTX-2337 with chemotherapy in recurrent ovarian cancer. Methods: VTX-2337 was tested in an ovarian cancer mouse model with an intact human immune system. Additionally, an open-label phase I study of VTX-2337 + pegylated liposomal doxorubicin (PLD) in recurrent ovarian cancer (NCT01294293, N=13) was performed. PLD (40 mg/m2) was given on day 1 of a 28-day cycle. Three dose levels of VTX-2337 (2.5, 3.0, 3.5 mg/m2, N=13) were serially tested and given by SC injection on days 3, 10, and 17. VTX-2337 (3.0 mg/m2) was also tested with paclitaxel (80 mg/m2; N=7) given on days 1, 8, and 15 of a 28 day cycle. Responses were evaluated using RECIST1.1. PK and serum immune cytokines were measured. Patients remained on therapy until toxicity or progression. Results: In the mouse model, clinical responses to PLD were increased. Innate immunity along with CD8+ T cell responses were also induced. In humans, treatment with PLD + VTX-2337 increased various cytokines and chemokines (G-CSF, MCP-1, MIP-1β, TNF-α). The PK of PLD was not affected by VTXE2337. The combination was well tolerated with no DLTs. AEs consisted of those seen with single-agent PLD (Gr 3/4 toxicities, N=6) or VTXE2337 (Gr 1/2 injection site reaction, transient fever, flu-like symptoms). There was 1 partial response (13%) and 63% had stable disease. Paclitaxel + VTX-2337 was also well tolerated. Conclusions: VTX-2337 enhances the effect of PLD in a preclinical model of ovarian cancer, and the combination is well-tolerated in patients. Clinical data and biomarkers consistent with immunostimulation, provide rationale for the on-going randomized, placebo-controlled, phase II trial comparing PLD vs PLD + VTX-2337 (GOG-3003, NCT01666444). Clinical trial information: NCT01666444.

Phase I study of ABT-888 in combination with carboplatin and gemcitabine in subjects with advanced solid tumors

2584^

Background: Veliparib (V) is an oral inhibitor of poly(ADP-ribose) polymerases (PARP)-1 and -2, which are essential for base excision repair of ssDNA breaks. BRCA deficient tumors are more sensitive to PARP inhibitors when used as monotherapy or in combination with DNA-damaging agents. The objectives of this study were to determine the maximum tolerated dose (MTD), pharmacokinetic interactions, and safety/tolerability profile of V in combination with carboplatin (C) and gemcitabine (G). Methods: Eligibility criteria included patients (pts) with metastatic or unresectable solid tumors for which C/G was a treatment option. During the study, eligibility was amended to limit prior chemotherapy regimens to ≤ 2. C AUC 4 /G 800 mg/m2was given intravenously on Day 1 and G given on Day 8 of 21 day cycles. To assess tolerability of C/G prior to V, V was started in Cycle 2. When C/G was stopped, pts could stay on monotherapy V until progression. Dose-escalation used a Bayesian continual reassessment method. Results: 59 pts (51 female, median age 52) were enrolled. The most common tumor types were ovarian (n=39) and breast (n=10). Germline BRCA mutations were known in 24 ovarian pts. 58 pts had prior chemotherapy (1-6 regimens, median 2), and 51 had prior platinum. Grade 3/4 AEs in >10% of pts were neutropenia, thrombocytopenia, anemia, and leukopenia. Dose limiting toxicities were thrombocytopenia (n=3) and neutropenia at V 310 mg twice daily (BID) and thrombocytopenia at 250 mg BID. Other frequent AEs were nausea, constipation, and fatigue. Preliminary results showed co-administration of V did not affect C or G pharmacokinetics. Treatment cycles (range, median) were 1-28, 5 for V; 2-10, 5 for C; and 2-10, 4 for G. Day 8 G was stopped in some pts to improve tolerability. 28 pts stayed on monotherapy V (1-23 cycles). Partial and complete responses were seen in 11 and 2 pts. Response rates were 47% (8/17) in known BCRA deficient ovarian, 25% (3/12) in other ovarian, and 13% (2/15) in other evaluable pts. Conclusions: V combined with C and G was tolerated with a safety profile similar to C and G alone. The MTD was V 250 mg BID, C AUC 4.0, G 800 mg/m2. Promising anti-tumor activity was observed in BRCA deficient ovarian pts. Clinical trial information: NCT01063816.

Progression-free and overall survival of a modified outpatient regimen of primary intravenous/intraperitoneal paclitaxel and intraperitoneal cisplatin in ovarian, fallopian tube, and primary peritoneal cancer

OBJECTIVE

GOG study 172 demonstrated improved progression-free (PFS) and overall (OS) survival for patients with stage III optimally debulked ovarian and peritoneal carcinoma treated with IV/IP paclitaxel and IP cisplatin compared to standard IV therapy. The inpatient administration, toxicity profile, and limited completion rate have been blamed for the lack of acceptance and widespread use of this regimen. We sought to evaluate the PFS, OS, toxicity, and completion rate of a modified outpatient IP regimen.

METHODS

Using a prospectively maintained database, we evaluated the outcomes of patients who underwent primary optimal cytoreduction for stage III ovarian, tubal, or peritoneal carcinoma followed by IV/IP chemotherapy from 1/05-3/09. Our modified regimen was as follows: IV paclitaxel (135 mg/m(2)) over 3h on day 1, IP cisplatin (75 mg/m(2)) on day 2, and IP paclitaxel (60 mg/m(2)) on day 8, given every 21 days for 6 cycles.

RESULTS

We identified 102 patients who initiated the modified IV/IP regimen and completed chemotherapy. The median follow-up was 43 months. The median age at diagnosis was 57 years (range, 23-76). Primary disease site was: ovary, 77 (75%); fallopian tube, 13 (13%); peritoneum, 12 (12%). FIGO stage was: IIIA, 8 (8%); IIIB, 4 (4%); IIIC, 90 (88%). Residual disease after cytoreduction was: none, 58 (57%); ≤ 1 cm, 44 (43%). The most frequent grade 3/4 toxicities were: neutropenia, 12 (12%); gastrointestinal, 8 (8%); neurologic, 6 (6%). Eighty-two (80%) of 102 patients completed 4 or more cycles of IV/IP therapy; 56 (55%) completed all 6 cycles. The median PFS and OS were 29 and 67 months, respectively.

CONCLUSIONS

By modifying the GOG 172 treatment regimen, convenience, toxicity, and tolerability appear improved, with survival outcomes similar to those of GOG 172. This modified IV/IP regimen warrants further study.

Macrophages and cathepsin proteases blunt chemotherapeutic response in breast cancer

The microenvironment is known to critically modulate tumor progression, yet its role in regulating treatment response is poorly understood. Here we found increased macrophage infiltration and cathepsin protease levels in mammary tumors following paclitaxel (Taxol) chemotherapy. Cathepsin-expressing macrophages protected against Taxol-induced tumor cell death in coculture, an effect fully reversed by cathepsin inhibition and mediated partially by cathepsins B and S. Macrophages were also found to protect against tumor cell death induced by additional chemotherapeutics, specifically etoposide and doxorubicin. Combining Taxol with cathepsin inhibition in vivo significantly enhanced efficacy against primary and metastatic tumors, supporting the therapeutic relevance of this effect. Additionally incorporating continuous low-dose cyclophosphamide dramatically impaired tumor growth and metastasis and improved survival. This study highlights the importance of integrated targeting of the tumor and its microenvironment and implicates macrophages and cathepsins in blunting chemotherapeutic response.

Phase II, open-label, randomized, multicenter study comparing the efficacy and safety of olaparib, a poly (ADP-ribose) polymerase inhibitor, and pegylated liposomal doxorubicin in patients with BRCA1 or BRCA2 mutations and recurrent ovarian cancer

PURPOSE

Olaparib (AZD2281), an orally active poly (ADP-ribose) polymerase inhibitor that induces synthetic lethality in BRCA1- or BRCA2-deficient cells, has shown promising clinical efficacy in nonrandomized phase II trials in patients with ovarian cancer with BRCA1 or BRCA2 deficiency. We assessed the comparative efficacy and safety of olaparib and pegylated liposomal doxorubicin (PLD) in this patient population.

PATIENTS AND METHODS

In this multicenter, open-label, randomized, phase II study, patients with ovarian cancer that recurred within 12 months of prior platinum therapy and with confirmed germline BRCA1 or BRCA2 mutations were enrolled. Patients were assigned in a 1:1:1 ratio to olaparib 200 mg twice per day or 400 mg twice per day continuously or PLD 50 mg/m(2) intravenously every 28 days. The primary efficacy end point was Response Evaluation Criteria in Solid Tumors (RECIST) -assessed progression-free survival (PFS). Secondary end points included objective response rate (ORR) and safety.

RESULTS

Ninety-seven patients were randomly assigned. Median PFS was 6.5 months (95% CI, 5.5 to 10.1 months), 8.8 months (95% CI, 5.4 to 9.2 months), and 7.1 months (95% CI, 3.7 to 10.7 months) for the olaparib 200 mg, olaparib 400 mg, and PLD groups, respectively. There was no statistically significant difference in PFS (hazard ratio, 0.88; 95% CI, 0.51 to 1.56; P = .66) for combined olaparib doses versus PLD. RECIST-assessed ORRs were 25%, 31%, and 18% for olaparib 200 mg, olaparib 400 mg, and PLD, respectively; differences were not statistically significant. Tolerability of both treatments was as expected based on previous trials.

CONCLUSION

The efficacy of olaparib was consistent with previous studies. However, the efficacy of PLD was greater than expected. Olaparib 400 mg twice per day is a suitable dose to explore in further studies in this patient population.

Phase II study of intraperitoneal paclitaxel plus cisplatin and intravenous paclitaxel plus bevacizumab as adjuvant treatment of optimal stage II/III epithelial ovarian cancer

PURPOSE

Intraperitoneal (IP) cisplatin and intravenous (IV) or IP paclitaxel constitute a standard therapy for optimally debulked ovarian cancer. Bevacizumab prolongs progression-free survival (PFS) when included in first-line IV chemotherapy. In this study, the safety and feasibility of adding bevacizumab to a first-line IP regimen were assessed.

PATIENTS AND METHODS

Treatment was as follows: paclitaxel 135 mg/m(2) IV over 3 hours day 1, cisplatin 75 mg/m(2) IP day 2, and paclitaxel 60 mg/m(2) IP day 8. Bevacizumab 15 mg/kg IV was given after paclitaxel on day 1 beginning in cycle 2. After six cycles of chemotherapy, bevacizumab was given every 3 weeks for 17 additional treatments. The primary end point was safety and tolerability determined by whether 60% of patients completed six cycles of IV/IP chemotherapy.

RESULTS

Of 41 treated patients, 30 (73%) received six cycles of IV/IP chemotherapy and 35 (85%) received at least four cycles. Three (27%) of those who discontinued chemotherapy did so because of complications related to bevacizumab (hypertension, n = 2; perforation, n = 1). Grades 3 to 4 toxicities included neutropenia (34%), vasovagal syncope (10%), hypertension (7%), nausea/vomiting (7%), hypomagnesemia (7%), and abdominal pain (7%). There were three grade 3 small bowel obstructions (7%) during cycles 3, 9, and 15. One patient died following rectosigmoid anastomotic dehiscence during cycle 4. Estimated median PFS is 28.6 months (95% CI, 19.1 to 38.9 months). Three patients (7%) had IP port malfunction.

CONCLUSION

The addition of bevacizumab to this IP regimen is feasible; however, bevacizumab may increase the risk of bowel obstruction/perforation. The observed median PFS is similar to that seen with IP/IV chemotherapy alone.

Abstract 549: Sensitization to chemotherapy by inhibition of cathepsin proteases in a mouse model of metastatic breast cancer

A growing body of evidence supports the role of the tumor microenvironment in promoting malignant progression and modulating the response to anti-cancer therapy. Tumor associated macrophages (TAMs) have been established as an important component of the tumor microenvironment, contributing to angiogenesis, matrix remodeling, invasion and metastasis. We and others have identified cysteine cathepsin proteases as key effectors of these pro-tumorigenic functions of TAMs. These same processes, which are integral to tumor progression, may also aid tumors in recovering from cytotoxic insults, thereby blunting our therapeutic efforts. There is thus a strong rationale for combinatorial targeting of both the tumor and the supporting stroma. We have uncovered such a phenomenon in a mouse model of metastatic mammary carcinogenesis (MMTV-PyMT). Following maximum tolerated dose paclitaxel treatment (TaxMTD), we observed an elevation in levels of circulating cathepsin-activity+ myeloid cells and a subsequent increase in macrophages and cathepsin activity levels in the tumor. In co-cultures, cathepsin-activity+ macrophages reduced paclitaxel-induced tumor cell death. Furthermore, the use of primary macrophages from various cathepsin null genetic backgrounds identified cathepsins B and S as mediators of this effect.

To determine whether cathepsin inhibition could therefore enhance the effects of chemotherapy, we treated MMTV-PyMT mice with both TaxMTD and a pan-cathepsin inhibitor, JPM. While JPM alone had no effect on mammary tumor burden, it significantly impaired tumor growth when combined with TaxMTD, demonstrating that the TaxMTD-induced elevation in tumor cathepsin activity is functionally relevant. To further our goal of simultaneous targeting of tumor and stroma, we added a low-dose cyclophosphamide regimen, which has been shown to have both anti-angiogenic and immune-stimulatory properties. This triple combination treatment was substantially more effective than any double or single drug combination. Importantly, metastatic burden was also significantly reduced in triple-treated mice as compared to controls, and long-term survival was improved. These studies suggest cathepsin+ macrophages are recruited to the tumor after TaxMTD treatment to promote tumor survival and recovery. The efficacy of combining cathepsin inhibition with paclitaxel highlights both the importance of integrated therapeutic targeting of tumor and stroma, as well as the role of TAMs in modulating resistance to chemotherapy. The addition of cysteine cathepsin inhibition to chemotherapeutic regimens thus holds considerable promise for clinical translation.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 549. doi:10.1158/1538-7445.AM2011-549

Survival in epithelial ovarian cancer: a multivariate analysis incorporating BRCA mutation status and platinum sensitivity

BACKGROUND

Patients with BRCA-associated ovarian cancer (OC) have a survival advantage over those with sporadic OC. To further explore this, we examined the impact of prognostic factors on disease-free survival (DFS) and overall survival (OS) in patients with known BRCA mutation status.

PATIENTS AND METHODS

We reviewed stage III-IV OC patients treated at our institution between 1 December 1996 and 30 September 2006 and also tested on protocol for BRCA mutations. Impact on DFS and OS was determined by Kaplan-Meier analysis and a Cox proportional hazards model.

RESULTS

Of the 110 patients, 36 had deleterious BRCA mutations [BRCA (+)] and 74 were BRCA wild type [BRCA(-)]. Thirty-one of 36 (86%) BRCA (+) and 60 of 74 (81%) BRCA (-) patients were platinum sensitive (P = 0.60). Median OS was longer for BRCA (+) patients (not reached versus 67.8 months; P = 0.02), but DFS was similar (26.9 versus 24.0, P = 0.3). On multivariate analysis, OS correlated with primary platinum sensitivity [HR = 0.15; 95% CI (confidence interval) 0.06-0.34] and BRCA (+) mutation status (HR = 0.33; 95% CI 0.12-0.86).

CONCLUSIONS

BRCA mutation status predicted OS independent of primary platinum sensitivity, suggesting that underlying tumor biology contributes to disease outcome and may be worthy of consideration in future clinical trial design.

Farletuzumab, a humanized monoclonal antibody against folate receptor alpha, in epithelial ovarian cancer: a phase I study

PURPOSE

Folate receptor α expression is highly restricted in normal adult tissues but upregulated in a wide range of human cancer types, including epithelial ovarian cancer. Farletuzumab, a humanized monoclonal antibody against folate receptor α, has shown antitumor activity and favorable toxicity in preclinical evaluation. This phase I, dose-escalation study was conducted to determine the safety of weekly i.v. farletuzumab and establish the maximum tolerated dose (MTD).

EXPERIMENTAL DESIGN

Patients with platinum-refractory or platinum-resistant epithelial ovarian cancer received farletuzumab (12.5-400 mg/m(2)) on days 1, 8, 15, and 22 of a 5-week cycle. Intrapatient dose escalation was not permitted. Dose-limiting toxicity (DLT) was defined by treatment-related adverse event of grade 3 or higher, and the MTD was the highest dose at which one or none of six patients experienced a DLT. Disease progression was recorded using Response Evaluation Criteria in Solid Tumors criteria and serum CA-125.

RESULTS

Twenty-five heavily pretreated patients were included in the safety, efficacy, and pharmacokinetic analyses. No DLTs or MTDs were encountered, and dose escalation was continued to farletuzumab 400 mg/m(2). C(max) and AUC(0-24) (area under the serum concentration-time curve) increased in an approximately dose-proportional manner, and a nuclear imaging substudy confirmed tumor targeting. There were no objective responses. Stable disease by Response Evaluation Criteria in Solid Tumors was observed in nine (36%) patients and CA-125 reduction in four. Three patients received continued therapy and completed a total of up to three cycles.

CONCLUSIONS

In this phase I study, farletuzumab administered as an i.v. infusion at doses of 12.5 to 400 mg/m(2) was generally safe and well tolerated in the management of heavily pretreated patients with epithelial ovarian cancer.

Oral poly(ADP-ribose) polymerase inhibitor olaparib in patients with BRCA1 or BRCA2 mutations and recurrent ovarian cancer: a proof-of-concept trial

BACKGROUND

Olaparib is a novel, orally active poly(ADP-ribose) polymerase (PARP) inhibitor that induces synthetic lethality in homozygous BRCA-deficient cells. We aimed to assess the efficacy and safety of olaparib for treatment of advanced ovarian cancer in patients with BRCA1 or BRCA2 mutations.

METHODS

In this international, multicentre, phase 2 study, we enrolled two sequential cohorts of women (aged >or=18 years) with confirmed genetic BRCA1 or BRCA2 mutations, and recurrent, measurable disease. The study was undertaken in 12 centres in Australia, Germany, Spain, Sweden, and the USA. The first cohort (n=33) was given continuous oral olaparib at the maximum tolerated dose of 400 mg twice daily, and the second cohort (n=24) was given continuous oral olaparib at 100 mg twice daily. The primary efficacy endpoint was objective response rate (ORR). This study is registered with ClinicalTrials.gov, number NCT00494442.

FINDINGS

Patients had been given a median of three (range 1-16) previous chemotherapy regimens. ORR was 11 (33%) of 33 patients (95% CI 20-51) in the cohort assigned to olaparib 400 mg twice daily, and three (13%) of 24 (4-31) in the cohort assigned to 100 mg twice daily. In patients given olaparib 400 mg twice daily, the most frequent causally related adverse events were nausea (grade 1 or 2, 14 [42%]; grade 3 or 4, two [6%]), fatigue (grade 1 or 2, ten [30%]; grade 3 or 4, one [3%]), and anaemia (grade 1 or two, five [15%]; grade 3 or 4, one [3%]). The most frequent causally related adverse events in the cohort given 100 mg twice daily were nausea (grade 1 or 2, seven [29%]; grade 3 or 4, two [8%]) and fatigue (grade 1 or 2, nine [38%]; none grade 3 or 4).

INTERPRETATION

Findings from this phase 2 study provide positive proof of concept of the efficacy and tolerability of genetically targeted treatment with olaparib in BRCA-mutated advanced ovarian cancer.

FUNDING

AstraZeneca.

Exploratory analysis of serum CA-125 response to surgery and the risk of relapse in patients with FIGO stage IIIC ovarian cancer

OBJECTIVE

To analyze whether serum CA-125 response to cytoreductive surgery before initiation of postoperative chemotherapy is associated with progression-free survival (PFS) in patients with stage IIIC ovarian carcinoma.

METHODS

We included consecutive patients with paired pre- and postoperative CA-125 measurements who underwent primary cytoreductive surgery followed by platinum-based chemotherapy between 1989 and 2006. The association of perioperative CA-125 changes with PFS was investigated using a time-to-event analysis. A Cox proportional hazards model was fit using clinical, surgical, and postoperative treatment characteristics.

RESULTS

The study included 307 evaluable patients. Overall, perioperative serum CA-125 changes were associated with PFS. The risk of disease progression increased incrementally as the magnitude of the serum CA-125 response to surgery decreased (trend test; P=0.003). This association was pronounced in optimally but not observed in suboptimally debulked patients. After optimal cytoreduction, a perioperative increase of serum CA-125 levels was strongly associated with an increased risk of relapse compared to patients who experienced a decline of 80% or more (adjusted HR=4.2; 95% CI: 2.04-8.66; P=0.0001).

CONCLUSION

Perioperative serum CA-125 changes are strongly associated with the risk of relapse in patients with optimally resected stage IIIC disease. The results of this study provide meaningful support for additional translational research correlating perioperative serum CA-125 responses of patients with molecular tumor characteristics. This may be useful for patient counseling and risk stratification during subsequent clinical trials as well as for the development of novel prognostic models.

Inhibition of cysteine cathepsin protease activity enhances chemotherapy regimens by decreasing tumor growth and invasiveness in a mouse model of multistage cancer

Increases in protease expression and activity are associated with malignant progression and poor patient prognosis in a number of human cancers. Members of the papain family of cysteine cathepsins are among the protease classes that have been functionally implicated in cancer. Inhibition of the cysteine cathepsin family using a pan-cathepsin inhibitor, JPM-OEt, led to tumor regression in the RIP1-Tag2 (RT2) mouse model of pancreatic islet cell tumorigenesis. The present study was designed to determine whether this cathepsin inhibitor, when used in combination with chemotherapy, would increase antitumor efficacy. RT2 mice were treated in a late-stage regression trial with three different chemotherapy regimens, alone or in combination with the cathepsin inhibitor, JPM-OEt. Cyclophosphamide was administered in either a maximum tolerated dose (MTD) regimen, a "metronomic" continuous low-dose regimen, or a "chemo-switch" regimen consisting of MTD followed by metronomic dosing. Mice were sacrificed at a defined end point and tumor burden was assessed followed by a detailed analysis of cell proliferation, apoptosis, vascularization, and invasiveness in the treated and control lesions. An additional cohort of mice was followed for survival analysis. The cathepsin inhibitor plus the chemo-switch regimen of cyclophosphamide led to the most pronounced reduction in tumor burden and greatest increase in overall survival. Cysteine cathepsin inhibition resulted in a significant decrease in tumor invasiveness, which was further augmented in combination with each of the chemotherapy dosing regimens. These results encourage the development and continuing evaluation of cysteine cathepsin inhibitors as cancer therapeutics.