Randomized phase II trial of farletuzumab plus chemotherapy versus placebo plus chemotherapy in low CA-125 platinum-sensitive ovarian cancer.

OBJECTIVE: The primary purpose of this study was to determine if farletuzumab, an antifolate receptor-α monoclonal antibody, improved progression-free survival (PFS) versus placebo when added to standard chemotherapy regimens in patients with platinum-sensitive recurrent ovarian cancer (OC) in first relapse (platinum-free interval: 6-36 months) with low cancer antigen 125 (CA-125) levels. METHODS: Eligibility included CA-125 ≤ 3 x upper limit of normal (ULN, 105 U/mL), high-grade serous, platinum-sensitive recurrent OC, previous treatment with debulking surgery, and first-line platinum-based chemotherapy with 1st recurrence between 6 and 36 months since frontline platinum-based treatment. Patients received investigator's choice of either carboplatin (CARBO)/paclitaxel (PTX) every 3 weeks or CARBO/pegylated liposomal doxorubicin (PLD) every 4 weeks x6 cycles in combination with either farletuzumab [5 mg/kg weekly] or placebo randomized in a 2:1 ratio. Maintenance treatment with farletuzumab (5 mg/kg weekly) or placebo was given until disease progression or intolerance. RESULTS: 214 patients were randomly assigned to farletuzumab+chemotherapy (142 patients) versus placebo+chemotherapy (72 patients). The primary efficacy endpoint, PFS, was not significantly different between treatment groups (1-sided α = 0.10; p-value = 0.25; hazard ratio [HR] = 0.89, 80% confidence interval [CI]: 0.71, 1.11), a median of 11.7 months (95% CI: 10.2, 13.6) versus 10.8 months (95% CI: 9.5, 13.2) for farletuzumab+chemotherapy and placebo+chemotherapy, respectively. No new safety concerns were identified with the combination of farletuzumab+chemotherapy. CONCLUSIONS: Adding farletuzumab to standard chemotherapy does not improve PFS in patients with OC who were platinum-sensitive in first relapse with low CA-125 levels. Folate receptor-α expression was not measured in this study. (Clinical Trial Registry NCT02289950).

Randomized Controlled Trial Testing the Efficacy of Platinum-Free Interval Prolongation in Advanced Ovarian Cancer: The MITO-8, MaNGO, BGOG-Ov1, AGO-Ovar2.16, ENGOT-Ov1, GCIG Study.

Purpose Platinum-based chemotherapy (PBC) for patients with progressing ovarian cancer (OC) is more effective with a longer time interval from previous platinum treatment (platinum-free interval [PFI]). In 1999, it was hypothesized that prolonging PFI with single-agent non-PBC (NPBC) may offer a strategy to improve overall outcome. MITO-8 aimed to verify this hypothesis commonly used in clinical practice although it has not been prospectively tested. Methods MITO-8 is an open-label, prospective, randomized, superiority trial. Patients with OC who experienced disease progression 6 to 12 months after their last platinum treatment were randomly assigned 1:1 to the experimental sequence of NPBC followed by PBC at subsequent relapse or the standard reverse treatment sequence. Overall survival (OS) was the primary end point. Results Two hundred fifteen patients were enrolled (standard arm [n = 108]; experimental arm [n = 107]). The trial ended before planned because of slow enrollment. PFI was prolonged in the experimental arm (median, 7.8 v 0.01 months). There was no OS benefit in the experimental arm (median, 21.8 v 24.5 months; hazard ratio, 1.38; 95% CI, 0.99 to 1.94; P = .06). Progression-free survival after the sequence was significantly shorter in the experimental arm (median, 12.8 v 16.4 months; hazard ratio, 1.41; 95% CI, 1.04 to 1.92; P = .025). Global quality-of-life change after three cycles was worse in the experimental arm. Slight differences were observed in the incidence of adverse effects. Conclusion MITO-8 supports the recommendation that PBC not be delayed in favor of an NPBC in patients with partially platinum-sensitive OC. PBC should be used as a control arm in future trials of new drugs in this setting.

A phase 2 randomised discontinuation trial of cabozantinib in patients with ovarian carcinoma.

BACKGROUND: Cabozantinib (XL184), an orally bioavailable inhibitor of vascular endothelial growth factor receptor 2 and MET, was assessed in a cohort of ovarian carcinoma patients as part of a phase 2 randomised discontinuation trial (RDT) with cohorts from nine different tumour types. PATIENTS AND METHODS: Patients received 100-mg cabozantinib daily. Those with stable disease (SD) per Response Evaluation Criteria in Solid Tumors at week 12 were randomised to cabozantinib or placebo. Primary end-points were objective response rate (ORR) at week 12 and progression-free survival (PFS) after random assignment. RESULTS: Seventy patients with ovarian carcinoma, 50% of whom were platinum refractory/resistant, were enrolled in this RDT. Median PFS from day 1 was 5.5 months for all patients. The ORR at week 12 was 21%; one patient achieved a complete response (CR), and 14 patients (20%) achieved a confirmed partial response (PR). The overall disease control rate (CR + PR + SD) at week 12 was 50%. Throughout the study, 70% of the patients with ≥1 postbaseline scan had tumour regression, and randomisation was discontinued early. For patients with SD randomised to cabozantinib, PFS was 5.9 months after randomisation. The most common grade 3/4 adverse events were diarrhoea (14%), palmar-plantar erythrodysesthesia syndrome (6%), asthenia (6%), hypertension (6%) and neutropenia (6%). Dose reductions were required in 37% of the patients during the first 12 weeks. CONCLUSION: Cabozantinib demonstrates clinical activity, with acceptable toxicities, in patients with ovarian carcinoma based on ORR and regression of tumour target lesions. REGISTRATION: This trial is registered at ClinicalTrial.gov (NCT00940225).

Role of the folate receptor in ovarian cancer treatment: evidence, mechanism, and clinical implications.

Folate can be transported into the cell by the reduced folate carrier (RFC), the proton-coupled folate transporter (PCFT), or the folate receptor (FR), of which various isoforms exist. While the RFC and PCFT are expressed by many normal cells, the FR is present only in a small proportion of normal tissues. In these tissues, the FR expression level is often low and restricted to the apical surface of polarized epithelial cells. In contrast, FR is expressed on the blood-accessible basal and lateral membranes of many types of epithelial cancer. Considering that FR is expressed in few nonmalignant cell types on luminal membranes generally not accessible for molecules transported in the blood, FR is considered a promising antitumor target. As FR expression seems associated with tumor progression and prognosis, anticancer therapies targeting FR are currently being developed, such as farletuzumab (Morphotek, Exton, PA, USA), IMGN853 (ImmunoGen, Waltham, MA, USA), vintafolide, and EC1456 (both Endocyte Inc., West Lafayette, IN, USA). FR expression could be used as a response-predictive biomarker for these treatments. The ability to identify patients and treat them with an effective therapy based on the known expression of the tumor marker would, indeed, be the next step in predictive medicine for these patients. This review summarizes the role of FR in ovarian cancer and the value of FR as a prognostic biomarker for ovarian cancer and a response-predictive biomarker for folate-targeted therapeutics.

Randomized phase III study of erlotinib versus observation in patients with no evidence of disease progression after first-line platin-based chemotherapy for ovarian carcinoma: a European Organisation for Research and Treatment of Cancer-Gynaecological Cancer Group, and Gynecologic Cancer Intergroup study.

PURPOSE: This trial evaluated the efficacy of maintenance erlotinib, an epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor, after first-line chemotherapy. PATIENTS AND METHODS: Eligible patients had high-risk International Federation of Gynecology and Obstetrics stage I or stage II to IV epithelial ovarian, primary peritoneal, or fallopian tube cancer and were not selected for EGFR expression. All patients underwent first-line platinum-based chemotherapy (CT) and showed no signs of progression at the end of CT. Patients were randomly assigned to maintenance erlotinib 150 mg orally daily for 2 years or to observation. EGFR immunohistochemistry (IHC), fluorescent in situ hybridization (FISH), and mutation analyses were performed in 318 patients. RESULTS: Between October 2005 and February 2008, 835 patients were randomly assigned (median follow-up, 51 months). Twenty-six percent of the patients stopped erlotinib as a result of adverse effects (of these, 67% were due to rash). For erlotinib and observation, respectively, the median progression-free survival was 12.7 and 12.4 months (hazard ratio [HR], 1.05; 95% CI, 0.90 to 1.23), and the median overall survival was 50.8 and 59.1 months (HR, 0.99; 95% CI, 0.81 to 1.20 months), respectively. No subgroup could be identified with improved effect of erlotinib, based on IHC or FISH for EGFR, or mutations in genes related to the EGFR pathway, or on rash during erlotinib therapy. However, patients with a positive FISH EGFR score had a worse overall survival (46.1 months) than those with a negative score (67.0 months; HR, 1.56; 95% CI, 1.01 to 2.40; P = .044). Global health/quality-of-life scores showed a significant difference during the first year (P = .0102) in favor of the observation arm. CONCLUSION: Maintenance erlotinib after first-line treatment in ovarian cancer did not improve progression-free or overall survival.

Randomized multicenter phase II trial comparing two schedules of etirinotecan pegol (NKTR-102) in women with recurrent platinum-resistant/refractory epithelial ovarian cancer.

PURPOSE: Etirinotecan pegol (NKTR-102) is a unique, long-acting topoisomerase-I inhibitor with prolonged systemic exposure to SN38 (7-ethyl-10-hydroxycamptothecin), the active metabolite of irinotecan. This randomized phase II trial investigated two dosing schedules of etirinotecan pegol in patients with platinum-resistant/refractory ovarian carcinoma. PATIENTS AND METHODS: A total of 71 eligible patients were randomly assigned to receive etirinotecan pegol 145 mg/m(2) every 14 or 21 days until progression or unacceptable adverse events (AEs). The primary end point was objective response rate (ORR) by RECIST (version 1.0). Secondary end points included response by Gynecologic Cancer Intergroup criteria, duration of ORR, progression-free survival (PFS), and overall survival (OS). RESULTS: The overall confirmed ORR was 20% (95% CI, 10% to 30%): 20% for once every 14 days, and 19% for once every 21 days. Median response duration was 4.1 months for once every 14 days and 4.0 months for once every 21 days. Median PFS for every 14 and every 21 days was 4.1 and 5.3 months, respectively, and median OS was 10.0 and 11.7 months, respectively. Etirinotecan pegol was well tolerated, with the most common grade 3 to 4 AEs being dehydration (24%) and diarrhea (23%). Diarrhea, dehydration, nausea, and neutropenia were less frequent with the schedule of once every 21 days than with that of once every 14 days. CONCLUSION: Both schedules of etirinotecan pegol showed activity in patients with heavily pretreated ovarian cancer, with encouraging ORR and PFS rates. The schedule of once every 21 days was better tolerated and had slightly longer PFS and OS rates. The treatment schedule of etirinotecan pegol 145 mg/m(2) once every 21 days was selected for the expanded phase II study and is preferred for future phase III studies. These findings provide support to directly compare etirinotecan pegol versus one of the approved drugs (eg, pegylated liposomal doxorubicin or topotecan) in platinum-resistant ovarian cancer.

Randomized, phase II, placebo-controlled, double-blind study with and without enzastaurin in combination with paclitaxel and carboplatin as first-line treatment followed by maintenance treatment in advanced ovarian cancer.

PURPOSE: Enzastaurin is an oral serine/threonine kinase inhibitor antitumor agent. Our phase II trial tested the efficacy and safety of enzastaurin added to a standard carboplatin/paclitaxel chemotherapy regimen in patients with newly diagnosed advanced ovarian cancer. PATIENTS AND METHODS: This was a randomized, placebo-controlled study in patients with International Federation of Gynecology and Obstetrics stage IIB to IV ovarian, fallopian tube, or peritoneal epithelial carcinoma. Patients were randomly assigned to six cycles of chemotherapy (paclitaxel/carboplatin ± enzastaurin [PCE/PC]) followed by maintenance therapy (enzastaurin/placebo). Primary end point was progression-free survival (PFS). Secondary measures included response rate, safety assessment, and translational research. RESULTS: A total of 142 patients were randomly assigned to PCE (n = 69) or PC (n = 73). Patients in the PCE group had a 3.7-month longer median PFS compared with patients in the PC group; this was not statistically significant (hazard ratio [HR], 0.80; 95% CI, 0.50 to 1.29; P = .37). Safety profiles of the treatment arms were comparable. Frequency of discontinuation because of adverse events was similar (PCE, 11.9%; PC, 9.7%). Multivariate analyses confirmed the importance of optimal debulking with regard to PFS (debulking optimal v suboptimal: HR, 0.51; 95% CI, 0.30 to 0.85; P = .009). HR for covariate stage (stage IIB to IIIB v IIIC to IV) was not statistically significant (0.75; 95% CI, 0.38 to 1.47; P = .40). Translational research of immunohistochemistry protein assays did not identify any markers significantly associated with treatment difference regarding PFS. CONCLUSION: The PCE combination increased PFS, but it was not significantly superior to PC in this phase II study.

Exposure-response relationship of AMG 386 in combination with weekly paclitaxel in recurrent ovarian cancer and its implication for dose selection.

PURPOSE: To characterize exposure-response relationships of AMG 386 in a phase 2 study in advanced ovarian cancer for the facilitation of dose selection in future studies. METHODS: A population pharmacokinetic model of AMG 386 (N = 141) was developed and applied in an exposure-response analysis using data from patients (N = 160) with recurrent ovarian cancer who received paclitaxel plus AMG 386 (3 or 10 mg/kg once weekly) or placebo. Reduction in the risk of progression or death with increasing exposure (steady-state area under the concentration-versus-time curve [AUC(ss)]) was assessed using Cox regression analyses. Confounding factors were tested in multivariate analysis. Alternative AMG 386 doses were explored with Monte Carlo simulations using population pharmacokinetic and parametric survival models. RESULTS: There was a trend toward increased PFS with increased AUC(ss) (hazard ratio [HR] for each one-unit increment in AUC(ss), 0.97; P = 0.097), suggesting that the maximum effect on prolonging PFS was not achieved at the highest dose tested (10 mg/kg). Among patients with AUC(ss) ≥ 9.6 mg h/mL, PFS was 8.1 months versus 5.7 months for AUC(ss) < 9.6 mg h/mL and 4.6 months for placebo. No relationship between AUC(ss) and grade ≥ 3 adverse events was observed. Simulations predicted that AMG 386 15 mg/kg once weekly would result in an AUC(ss) ≥ 9.6 mg h/mL in > 90% of patients with median PFS of 8.2 months versus 5.0 months for placebo (HR [15 mg/kg vs. placebo], 0.56). CONCLUSIONS: Increased exposure to AMG 386 was associated with improved clinical outcomes in recurrent ovarian cancer, supporting the evaluation of a higher dose in future studies.

Randomized, double-blind, placebo-controlled phase II study of AMG 386 combined with weekly paclitaxel in patients with recurrent ovarian cancer.

PURPOSE: To estimate the efficacy and toxicity of AMG 386, an investigational peptide-Fc fusion protein that neutralizes the interaction between the Tie2 receptor and angiopoietin-1/2, plus weekly paclitaxel in patients with recurrent ovarian cancer. PATIENTS AND METHODS: Patients with recurrent epithelial ovarian, fallopian tube, or primary peritoneal cancer were randomly assigned 1:1:1 to receive paclitaxel (80 mg/m(2) once weekly [QW], 3 weeks on/1 week off) plus intravenous AMG 386 10 mg/kg QW (arm A), AMG 386 3 mg/kg QW (arm B), or placebo QW (arm C). The primary end point was progression-free survival (PFS). Secondary end points included overall survival, objective response, CA-125 response, safety, and pharmacokinetics. RESULTS: One hundred sixty-one patients were randomly assigned. Median PFS was 7.2 months (95% CI, 5.3 to 8.1 months) in arm A, 5.7 months (95% CI, 4.6 to 8.0 months) in arm B, and 4.6 months (95% CI, 1.9 to 6.7 months) in arm C. The hazard ratio for arms A and B combined versus arm C was 0.76 (95% CI, 0.52 to 1.12; P = .165). Further analyses suggested an exploratory dose-response effect for PFS across arms (Tarone's test, P = .037). Objective response rates for arms A, B, and C were 37%, 19%, and 27%, respectively. The incidence of grade ≥ 3 adverse events (AEs) in arms A, B, and C was 65%, 55%, and 64%, respectively. Frequent AEs included hypertension (8%, 6%, and 5% in arms A, B, and C, respectively), peripheral edema (71%, 51%, and 22% in arms A, B, and C, respectively), and hypokalemia (21%, 15%, and 5% in arms A, B, and C, respectively). AMG 386 exhibited linear pharmacokinetic properties at the tested doses. CONCLUSION: AMG 386 combined with weekly paclitaxel was tolerable, with a manageable and distinct toxicity profile. The data suggest evidence of antitumor activity and a dose-response effect, warranting further studies in ovarian cancer.

Trabectedin plus pegylated liposomal Doxorubicin in recurrent ovarian cancer.

PURPOSE: The objective of this study was to compare the efficacy and safety of trabectedin plus pegylated liposomal doxorubicin (PLD) with that of PLD alone in women with recurrent ovarian cancer after failure of first-line, platinum-based chemotherapy. PATIENTS AND METHODS: Women > or = 18 years, stratified by performance status (0 to 1 v 2) and platinum sensitivity, were randomly assigned to receive an intravenous infusion of PLD 30 mg/m(2) followed by a 3-hour infusion of trabectedin 1.1 mg/m(2) every 3 weeks or PLD 50 mg/m(2) every 4 weeks. The primary end point was progression-free survival (PFS) by independent radiology assessment. RESULTS: Patients (N = 672) were randomly assigned to trabectedin/PLD (n = 337) or PLD (n = 335). Median PFS was 7.3 months with trabectedin/PLD v 5.8 months with PLD (hazard ratio, 0.79; 95% CI, 0.65 to 0.96; P = .0190). For platinum-sensitive patients, median PFS was 9.2 months v 7.5 months, respectively (hazard ratio, 0.73; 95% CI, 0.56 to 0.95; P = .0170). Overall response rate (ORR) was 27.6% for trabectedin/PLD v 18.8% for PLD (P = .0080); for platinum-sensitive patients, it was 35.3% v 22.6% (P = .0042), respectively. ORR, PFS, and overall survival among platinum-resistant patients were not statistically different. Neutropenia was more common with trabectedin/PLD. Grade 3 to 4 transaminase elevations were also more common with the combination but were transient and noncumulative. Hand-foot syndrome and mucositis were less frequent with trabectedin/PLD than with PLD alone. CONCLUSION: When combined with PLD, trabectedin improves PFS and ORR over PLD alone with acceptable tolerance in the second-line treatment of recurrent ovarian cancer.