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).

Safety and activity of anti-mesothelin antibody-drug conjugate anetumab ravtansine in combination with pegylated-liposomal doxorubicin in platinum-resistant ovarian cancer: multicenter, phase Ib dose escalation and expansion study.

OBJECTIVES: Anetumab ravtansine is an antibody-drug conjugate consisting of a fully human anti-mesothelin monoclonal antibody conjugated to cytotoxic maytansinoid tubulin inhibitor DM4. Mesothelin is highly expressed in ovarian cancer. This phase Ib study determines the safety, pharmacokinetics, and anti-tumor activity of anetumab ravtansine and pegylated liposomal doxorubicin in mesothelin-expressing platinum-resistant ovarian cancer. METHODS: Anetumab ravtansine (5.5 or 6.5 mg/kg) and pegylated liposomal doxorubicin (30 mg/m2) were administered intravenously every 3 weeks to 65 patients with platinum-resistant epithelial ovarian cancer. Mesothelin expression was assessed by central immunohistochemistry. Adverse events, tumor response (RECIST 1.1), and progression-free survival were determined. Biomarker samples were assessed by ELISA and next-generation sequencing. RESULTS: In dose escalation, nine patients received anetumab ravtansine across two doses (5.5 or 6.5 mg/kg). The maximum tolerated dose of anetumab ravtansine was 6.5 mg/kg every 3 weeks and no dose-limiting toxicities were observed. In dose expansion, 56 patients were treated at the maximum tolerated dose. The most common treatment-emergent adverse events of any grade were nausea (47.7%), decreased appetite (43.1%), fatigue (38.5%), diarrhea (32.3%), and corneal disorder (29.2%). In all treated patients the objective response rate was 27.7% (95% CI 17.3% to 40.2%), including one complete (1.5%) and 17 partial responses (26.2%), with median duration of response of 7.6 (95% CI 3.3 to 10.2) months and median progression-free survival of 5.0 (95% CI 3.2 to 6.0) months. In an exploratory analysis of a sub-set of patients (n=19) with high mesothelin expression who received ≤3 prior lines of systemic therapy, the objective response rate was 42.1% (95% CI 20.3% to 66.5%) with a median duration of response of 8.3 (95% CI 4.1 to 12.0) months and median progression-free survival of 8.5 (95% CI 4.0 to 11.4) months. CONCLUSIONS: Anetumab ravtansine and pegylated liposomal doxorubicin showed tolerability and promising clinical activity. These results established the dose schedule and the mesothelin-positive target population of this combination for a phase III study in platinum-resistant ovarian cancer. TRIAL REGISTRATION NUMBER: NCT02751918.

Phase 1b study of AVB-500 in combination with paclitaxel or pegylated liposomal doxorubicin platinum-resistant recurrent ovarian cancer.

OBJECTIVE: GAS6 and AXL are expressed in high-grade serous ovarian cancer but not in normal ovarian tissue. AVB-500, a novel high affinity Fc-sAXL fusion protein, binds GAS6 preventing AXL signaling. This Phase 1b study (NCT03639246) evaluated safety, efficacy, and exploratory predictive markers of AVB-500 combined with paclitaxel (PAC) or pegylated liposomal doxorubicin (PLD) in patients with platinum-resistant ovarian cancer (PROC), and used a model informed drug development (MIDD) approach for identification of the recommended phase 2 dose (RP2D). METHODS: Eligible patients received AVB-500 at 10, 15, or 20 mg/kg IV q2wk combined with PAC (n = 23) or PLD (n = 30). Patients were treated until progression or unacceptable toxicity. All were followed for survival. RESULTS: No dose limiting toxicities were observed and serum GAS6 was completely suppressed across the three dose levels evaluated. AVB-500 + PAC yielded better clinical activity than AVB-500 + PLD with an ORR of 34.8% (8/23, 2 complete responses) and median DoR, PFS, and OS of 7.0, 3.1, and 10.3 months, respectively. Subgroup analyses showed AVB-500 + PAC patients who had no prior bevacizumab or whose AVB-500 trough levels were >13.8 mg/L exhibited the best clinical response. The ORR and median PFS and OS in patients with these characteristics were ≥50%, ≥7.5 months, and ≥19 months, respectively. Given AVB-500 nor the combination with chemotherapy was expected to cause DLTs, the RP2D of AVB-500 was 15 mg/kg identified using an MIDD approach. CONCLUSION: AVB-500 was well-tolerated in combination with PAC or PLD and contributed to the clinical activity of PAC in PROC patients. Subgroup analyses identified a population of PROC patients who may benefit the most from AVB-500 treatment, which will be further assessed in an ongoing Phase 3 PROC trial.

A phase 3 randomized, open-label, multicenter trial for safety and efficacy of combined trabectedin and pegylated liposomal doxorubicin therapy for recurrent ovarian cancer.

OBJECTIVE: This phase 3 study aimed to compare overall survival (OS) of women with platinum-sensitive, recurrent ovarian cancer (ROC) treated with third-line trabectedin (T) + pegylated liposomal doxorubicin (PLD) vs. PLD monotherapy. METHODS: Women with advanced-relapsed epithelial ovarian cancer were randomly assigned 1: 1 to intravenous infusions of either T + PLD (trabectedin 1.1 mg/m2 for 3 h; PLD 30 mg/m2 for 1.5 h, every 3 weeks) or PLD (50 mg/m2 for 1.5 h, every 4 weeks). Primary endpoint was OS. Secondary endpoints included investigator-assessed progression free survival (PFS) and objective response rates (ORR). At randomization, patients were stratified by time from last dose of first-line platinum therapy to disease progression, ECOG grade 0 or 1, BRCA1/2 germline mutational status, and prior PLD therapy. Exploratory endpoints included OS, PFS, and ORR in the stratified subgroups (PFI, ECOG, BRCA1/2 status, and prior PLD therapy). This trial is registered with ClinicalTrials.gov, number NCT01846611. RESULTS: 576 patients were randomized (T + PLD, n = 289; PLD, n = 287). Median OS was 23.8 months with T + PLD vs. 22.2 months with PLD (HR:0.92, 95%CI:0.73-1.18; p = 0.52). Median PFS was 7.52 vs. 7.26 months (HR:0.93, 95%CI:0.76-1.15; p = 0.52); ORR was 46% vs. 35.9% (OR:1.52, 95%CI:1.07-2.16; p = 0.01). Patients with BRCA1/2 mutations had median OS of 34.2 months with T + PLD vs. 20.9 months with PLD (HR:0.54, 95%CI:0.33-0.90; p = 0.016). Patients with BRCA1/2 mutations had median PFS of 10.1 months with T + PLD vs. 7.6 months with PLD (HR:0.72, 95%CI:0.48-1.08; p = 0.039). Patients with BRCA1/2 mutations and a 6-12 months platinum-free interval (PFI), median OS was 31.5 vs. 14.9 months, respectively (HR:0.37, 95%CI:0.17-0.82; p = 0.011). Grade 3-4 AEs were higher in T + PLD (79%) vs. PLD (54%). CONCLUSION: Combination of T and PLD did not show favorable OS benefit nor safety; however, patients with germline BRCA1/2 mutations and/or a PFI of 6-12 months appear to have clinically relevant survival benefit with T + PLD. No new safety signals were identified.

Equivalency challenge: Evaluation of Lipodox® as the generic equivalent for Doxil® in a human ovarian cancer orthotropic mouse model.

BACKGROUND: The objective of this study was to evaluate the in vivo growth inhibition activity and tumor distribution of Doxil® compared to Lipodox® as its generic (GLD) in human ovarian cancer orthotopic mouse model. METHODS: In the efficacy study 50 mice were randomized to: vehicle, Doxil® 5mg/kg or 10mg/kg, or GLD 5mg/kg or 10mg/kg for a total of three cycles with monitoring for response and toxicity with 10 mice in each arm. In the microdialysis(MD) study, 60 mice were randomized to: Doxil® 5mg/kg or 10mg/kg, or GLD 5mg/kg or 10mg/kg single dose (n=15 mice/arm). MD sample time points included total of 29 samples from baseline through 100h and were evaluated with a validated PaperSpray LC/MS assay. RESULTS: There was 15.7% decrease (p<0.0001) in efficacy of GLD the 5mg/kg and 21.3% decrease (p<0.0001) in efficacy of the 10mg/kg dose of GLD when compared to equivalent doses of Doxil®. The intratumoral concentration for the GLD ranged from 1.0 to 25.5ng/mL (5mg/kg) and 2.9-35.6ng/mL (10mg/kg) compared to 2.7-42.2ng/mL (p<0.04, 5mg/kg) and 2.0-76ng/mL (p<0.02, 10mg/kg) for the Doxil®, respectively. CONCLUSION: Significant differences in preclinical efficacy were observed between Doxil® and GLD. These may be due to significant pharmacodynamic effects of drug distribution and decrease uptake of GLD in tumor tissue. A prospective clinical comparison of these two products is warranted to determine equivalency.

Is it equivalent? Evaluation of the clinical activity of single agent Lipodox® compared to single agent Doxil® in ovarian cancer treatment.

BACKGROUND: In response to the critical shortage of liposomal doxorubicin (Doxil®) in the United States, the Food and Drug Administration (FDA) approved temporary importation of doxorubicin hydrochloride liposome (Lipodox®). The objective was to compare toxicity and clinical activity of Lipodox® with Doxil®. METHODS: Recurrent ovarian cancer patients who received Lipodox® were compared 3:1 to matched control Doxil® patients who had received Doxil®. Patients were matched based on age, stage, dose, platinum sensitivity, and prior treatments from an existing de-identified database. Patients receiving combination regimens were excluded. RESULTS: The data from 40 Lipodox® patients was compared to 120 matched control Doxil® patients. In this study, 17 (42.5%) of the Lipodox® patients were switched to Doxil®. The overall response rate Lipodox® was 4.3% (1/23) compared to 18% (20/111) in matched control Doxil® patients. In the platinum-sensitive patients, 100% progressed in the Lipodox® group compared to 78.4% in matched control Doxil® patients. The mean time to progression was 4.1 ± 2.8 months for Lipodox® and 6.2 ± 7.2 months in control Doxil®s (p = 0·25). Toxicity was similar in the Lipodox® group and control Doxil® group. CONCLUSION: Lipodox® for treatment of recurrent ovarian cancer did not appear to have equivalent efficacy compared to Doxil®. A prospective clinical study is warranted before Lipodox® can be deemed equivalent substitution for Doxil®.

Evaluation of pegylated liposomal doxorubicin dose on the adverse drug event profile and outcomes in treatment of recurrent endometrial cancer.

OBJECTIVE: This study aims to determine factors that may increase the likelihood of adverse drug events (ADEs) in patients with recurrent endometrial cancer treated with pegylated liposomal doxorubicin (PLD) as well as this agent's impact on clinical outcomes. METHODS: The treatment records of patients with endometrial cancer who received PLD at The University of Texas, MD Anderson Cancer Center, from 1996 to 2006 were reviewed. Patient demographics, PLD dose, ADEs, use of supportive care interventions, disease progression, and survival were extracted. Logistical regression analysis was used to identify factors that were associated with higher incidence of ADEs and that influenced survival. RESULTS: A total of 60 patients with recurrent endometrial cancer were identified who experienced 122 ADEs. The most commonly reported ADEs were nausea (18.9%), palmar-plantar erythrodysesthesia (PPE; 16.4%), muscle weakness (12.3%), mucositis (10.7%), and peripheral neuropathy (9.8%). Seventeen patients (28%) required a dose reduction because of ADEs. However, only 5 (8.3%) patients discontinued therapy because of toxicity. Cooling mechanisms were used in 19 patients to prevent PPE, although 9 of these patients still experienced PPE. Treatment with 6 or more cycles of PLD was associated with increased incidence of neutropenia (P = 0.045), peripheral neuropathy (P = 0.004), and PPE (P < 0.001). No differences in progression-free survival or time to progression were found between the doses of PLD; however, there was an assessable trend toward increased survival with doses of 40 mg/m(2). CONCLUSIONS: Although there was no association with dose level and ADEs, more cycles received increased the incidence of toxicities, including PPE and neuropathy. There was no association between different doses of PLD and progression-free survival or time to progression.

Cardiac safety of trabectedin monotherapy or in combination with pegylated liposomal doxorubicin in patients with sarcomas and ovarian cancer.

BACKGROUND: As with other alkylating agents, cardiac dysfunction can occur with trabectedin therapy for advanced soft tissue sarcomas (STS) or recurrent ovarian cancer (ROC) where treatment options for advanced disease are still limited. Cardiac safety for trabectedin monotherapy (T) for STS or in combination with pegylated liposomal doxorubicin (T+PLD) for ROC was evaluated in this retrospective postmarketing regulatory commitment. METHODS: Patient data for multiple cardiac-related treatment-emergent adverse events (cTEAEs) were evaluated in pooled analyses of ten phase 2 trials, one phase 3 trial in STS (n = 982), and two phase 3 trials in ROC (n = 1231). RESULTS: Multivariate analyses on pooled trabectedin data revealed that cardiovascular medical history (risk ratio [RR (95% CI)]: 1.90 [1.24-2.91]; p = 0.003) and age ≥65 years (RR [95% CI]: 1.78 [1.12-2.83]; p = 0.014) were associated with increased risk for cTEAEs. Multivariate analyses showed increased risk of experiencing cTEAEs with T+PLD compared to PLD monotherapy (RR [95% CI]: 2.70 [1.75-4.17]; p < 0.0001) and with history of prior cardiac medication (RR [95% CI]: 1.88 [1.16-3.05]; p = 0.010). CONCLUSIONS: For patients with STS or ROC who still have limited treatment options, trabectedin may be initiated after carefully considering benefit versus risk. Trial Registration (ClinicalTrials.gov): NCT01343277; NCT00113607; NCT01846611.

MILO/ENGOT-ov11: Binimetinib Versus Physician's Choice Chemotherapy in Recurrent or Persistent Low-Grade Serous Carcinomas of the Ovary, Fallopian Tube, or Primary Peritoneum.

PURPOSE: Low-grade serous ovarian carcinomas (LGSOCs) have historically low chemotherapy responses. Alterations affecting the MAPK pathway, most commonly KRAS/BRAF, are present in 30%-60% of LGSOCs. The purpose of this study was to evaluate binimetinib, a potent MEK1/2 inhibitor with demonstrated activity across multiple cancers, in LGSOC. METHODS: This was a 2:1 randomized study of binimetinib (45 mg twice daily) versus physician's choice chemotherapy (PCC). Eligible patients had recurrent measurable LGSOC after ≥ 1 prior platinum-based chemotherapy but ≤ 3 prior chemotherapy lines. The primary end point was progression-free survival (PFS) by blinded independent central review (BICR); additional assessments included overall survival (OS), overall response rate (ORR), duration of response (DOR), clinical-benefit rate, biomarkers, and safety. RESULTS: A total of 303 patients were randomly assigned to an arm of the study at the time of interim analysis (January 20, 2016). Median PFS by BICR was 9.1 months (95% CI, 7.3 to 11.3) for binimetinib and 10.6 months (95% CI, 9.2 to 14.5) for PCC (hazard ratio,1.21; 95%CI, 0.79 to 1.86), resulting in early study closure according to a prespecified futility boundary after 341 patients had enrolled. Secondary efficacy end points were similar in the two groups: ORR 16% (complete response [CR]/partial responses[PRs], 32) versus 13% (CR/PRs, 13); median DOR, 8.1 months (range, 0.03 to ≥ 12.0 months) versus 6.7 months (0.03 to ≥ 9.7 months); and median OS, 25.3 versus 20.8 months for binimetinib and PCC, respectively. Safety results were consistent with the known safety profile of binimetinib; the most common grade ≥ 3 event was increased blood creatine kinase level (26%). Post hoc analysis suggests a possible association between KRAS mutation and response to binimetinib. Results from an updated analysis (n = 341; January 2019) were consistent. CONCLUSION: Although the MEK Inhibitor in Low-Grade Serous Ovarian Cancer Study did not meet its primary end point, binimetinib showed activity in LGSOC across the efficacy end points evaluated. A higher response to chemotherapy than expected was observed and KRAS mutation might predict response to binimetinib.

Focal adhesion kinase targeting using in vivo short interfering RNA delivery in neutral liposomes for ovarian carcinoma therapy.

PURPOSE: Focal adhesion kinase (FAK) plays a critical role in ovarian cancer cell survival and in various steps in the metastatic cascade. Based on encouraging in vitro results with FAK silencing, we examined the in vivo therapeutic potential of this approach using short interfering RNA (siRNA) in the neutral liposome 1,2-dioleoyl-sn-glycero-3-phosphatidylcholine (DOPC). EXPERIMENTAL DESIGN: Therapy experiments of FAK siRNA with or without docetaxel were done using human ovarian cancer cell lines SKOV3ip1, HeyA8, and HeyA8MDR in nude mice. Additional experiments with a cisplatin-resistant cell line (A2780-CP20) were also done. Assessments of angiogenesis (CD31), cell proliferation (proliferating cell nuclear antigen), and apoptosis (terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling) were done using immunohistochemical analysis. RESULTS: A single dose of FAK siRNA-DOPC was highly effective in reducing in vivo FAK expression for up to 4 days as assayed by Western blot and immunohistochemical analysis. Therapy experiments were started 1 week after injection of the ovarian cancer cells. Treatment with FAK siRNA-DOPC (150 mug/kg twice weekly) reduced mean tumor weight by 44% to 72% in the three cell lines compared with the control group (Ps < 0.05 for HeyA8, A2780-CP20, and SKOV3ip1). When FAK siRNA-DOPC was combined with docetaxel, there was even greater reduction in mean tumor weight in all models (all Ps < 0.05). Similar results were observed in combination with cisplatin. Treatment with FAK siRNA-DOPC plus docetaxel resulted in decreased microvessel density, decreased expression of vascular endothelial growth factor and matrix metalloproteinase-9, and increased apoptosis of tumor-associated endothelial cells and tumor cells. CONCLUSIONS: Taken together, these findings suggest that FAK siRNA-DOPC plus docetaxel or platinum might be a novel therapeutic approach against ovarian cancer.

Preclinical Mammalian Safety Studies of EPHARNA (DOPC Nanoliposomal EphA2-Targeted siRNA).

To address the need for efficient and biocompatible delivery systems for systemic siRNA delivery, we developed 1,2-Dioleoyl-sn-Glycero-3-Phosphatidylcholine (DOPC) nanoliposomal EphA2-targeted therapeutic (EPHARNA). Here, we performed safety studies of EPHARNA in murine and primate models. Single dosing of EPHARNA was tested at 5 concentrations in mice (N = 15 per group) and groups were sacrificed on days 1, 14, and 28 for evaluation of clinical pathology and organ toxicity. Multiple dosing of EPHARNA was tested in mice and Rhesus macaques twice weekly at two dose levels in each model. Possible effects on hematologic parameters, serum chemistry, coagulation, and organ toxicity were assessed. Following single-dose EPHARNA administration to mice, no gross pathologic or dose-related microscopic findings were observed in either the acute (24 hours) or recovery (14 and 28 days) phases. The no-observed-adverse-effect level (NOAEL) for EPHARNA is considered >225 µg/kg when administered as a single injection intravenously in CD-1 mice. With twice weekly injection, EPHARNA appeared to stimulate a mild to moderate inflammatory response in a dose-related fashion. There appeared to be a mild hemolytic reaction in the female mice. In Rhesus macaques, minimal to moderate infiltration of mononuclear cells was found in some organs including the gastrointestinal tract, heart, and kidney. No differences attributed to EPHARNA were observed. These results demonstrate that EPHARNA is well tolerated at all doses tested. These data, combined with previously published in vivo validation studies, have led to an ongoing first-in-human phase I clinical trial (NCT01591356). Mol Cancer Ther; 16(6); 1114-23. ©2017 AACR.

Intraperitoneal delivery of liposomal siRNA for therapy of advanced ovarian cancer.

PURPOSE: Intravenous (IV) delivery of siRNA incorporated into neutral liposomes allows efficient delivery to tumor tissue, and has therapeutic efficacy in preclinical proof-of-concept studies using EphA2-targeting siRNA. We sought to determine whether intraperitoneal (IP) delivery of these siRNA complexes was as effective at delivery and therapy as IV delivery. EXPERIMENTAL DESIGN: SiRNA was incorporated into the neutral liposome 1,2-dioleoyl-sn-glycero-3-phosphatidylcholine (DOPC). Alexa555-siRNA-DOPC was injected IP into nude mice bearing established ovarian tumors, and organs were collected for microscopic fluorescent examination. Subsequently, therapeutic efficacy of the IP versus IV routes was directly compared. RESULTS: Alexa555-siRNA in DOPC liposomes injected IP was diffusely distributed into intraperitoneal ovarian tumors. Delivery was also seen deeply into the liver and kidney parenchyma, suggesting that the predominant means of distribution was through the vasculature, rather than direct diffusion from the peritoneal cavity. In mice with orthotopic ovarian tumors, treatment with combined paclitaxel and IP EphA2-targeting siRNA-DOPC reduced tumor growth by 48-81% compared to paclitaxel/control siRNA-DOPC IP (HeyA8: 0.34 g v 0.66 g; SKOV3ip1: 0.04 v 0.21, p<0.01). This reduction was comparable to concurrently-treated mice with paclitaxel and EphA2 siRNA-DOPC injected IV, which showed a reduction in growth by 45-69% compared to paclitaxel/control siRNA-DOPC injected IV (HeyA8: 0.23g v. 0.42g; SKOV3ip1: 0.04 v. 0.13 g). CONCLUSIONS: IP injection of siRNA incorporated in DOPC allows intra-tumoral delivery and has therapeutic efficacy in orthotopic ovarian tumors. These findings may have therapeutic implications for siRNA-based strategies.

PRECEDENT: a randomized phase II trial comparing vintafolide (EC145) and pegylated liposomal doxorubicin (PLD) in combination versus PLD alone in patients with platinum-resistant ovarian cancer.

PURPOSE: Vintafolide (EC145) is a folic acid-desacetylvinblastine conjugate that binds to the folate receptor (FR), which is expressed on the majority of epithelial ovarian cancers. This randomized phase II trial evaluated vintafolide combined with pegylated liposomal doxorubicin (PLD) compared with PLD alone. The utility of an FR-targeted imaging agent, (99m)Tc-etarfolatide (EC20), in selecting patients likely to benefit from vintafolide was also examined. PATIENTS AND METHODS: Women with recurrent platinum-resistant ovarian cancer who had undergone ≤ two prior cytotoxic regimens were randomly assigned at a 2:1 ratio to PLD (50 mg/m(2) intravenously [IV] once every 28 days) with or without vintafolide (2.5 mg IV three times per week during weeks 1 and 3). Etarfolatide scanning was optional. The primary objective was to compare progression-free survival (PFS) between the groups. RESULTS: The intent-to-treat population comprised 149 patients. Median PFS was 5.0 and 2.7 months for the vintafolide plus PLD and PLD-alone arms, respectively (hazard ratio [HR], 0.63; 95% CI, 0.41 to 0.96; P = .031). The greatest benefit was observed in patients with 100% of lesions positive for FR, with median PFS of 5.5 compared with 1.5 months for PLD alone (HR, 0.38; 95% CI, 0.17 to 0.85; P = .013). The group of patients with FR-positive disease (10% to 90%) experienced some PFS improvement (HR, 0.873), whereas patients with disease that did not express FR experienced no PFS benefit (HR, 1.806). CONCLUSION: Vintafolide plus PLD is the first combination to demonstrate an improvement over standard therapy in a randomized trial of patients with platinum-resistant ovarian cancer. Etarfolatide can identify patients likely to benefit from vintafolide.

Determination of the optimal combination chemotherapy regimen for treatment of platinum-resistant ovarian cancer in nude mouse model.

OBJECTIVE: The primary objective of this study was to evaluate the potential to increase the in vivo activity of liposomal doxorubicin when administered in combination with other chemotherapeutic agents such as topotecan, docetaxel, gemcitabine, capecitabine, or celecoxib in an ovarian cancer xenograft mouse model to identify new treatment options for recurrent platinum-sensitive/resistant ovarian cancer. METHODS: This was a five-arm study in two xenograft ovarian cancer mouse models, ES-2 (platinum-sensitive), and OVCAR3 (platinumresistant), to evaluate the combination of liposomal doxorubicin with the common chemotherapeutic agents. Each cell line had five mice for each treatment arm, five vehicle control mice, and five liposomal doxorubicin alone control mice. Experiments were done in duplicate. RESULTS: The percentage tumor reduction ranged from 52% to 74.1% for the single-agent treatment arms. Tumor growth inhibition and regression (response) was improved on the combination treatment arms ranging from 76.1% to 100%. We observed increased activity in the liposomal doxorubicin plus topotecan arm, with a 27.3% improvement in response, compared with either agent alone. CONCLUSIONS: The addition of liposomal doxorubicin demonstrated increased antitumor activity compared with either agent used alone. The most active combination treatment arm was liposomal doxorubicin with topotecan which is consistent with recent clinical study reports of enhanced activity with the combination of topoisomerase I and topoisomerase II agents. Additional studies are warranted to evaluate the efficacy and safety to optimize the combination of liposomal doxorubicin and topotecan for the treatment of recurrent or refractory ovarian cancer.

Early changes in CA125 after treatment with pegylated liposomal doxorubicin or topotecan do not always reflect best response in recurrent ovarian cancer patients.

PURPOSE: To examine early changes in CA125 relative to objective response in patients with recurrent ovarian cancer treated with pegylated liposomal doxorubicin (PLD) or topotecan and to compare the CA125 trends between the two chemotherapeutics. PATIENTS AND METHODS: Patients with recurrent ovarian cancer, all of whom had measurable or evaluable disease, were randomized to receive 50 mg/m2 PLD every 28 days (n = 239) or 1.5 mg/m2 topotecan for 5 days every 21 days (n = 235) as part of a previously reported multicenter study. CA125 measurements were obtained prior to therapy and with each cycle of administration. Assessable patients underwent radiographic evaluation for response after two cycles of therapy. Objective responses were compared to trends in CA125 values at the end of cycles 1 and 2. CA125 changes were categorized as baseline (+/-10%), +/- 10%-25% variance, and > 25% variance. RESULTS: Among patients treated with PLD, 50% of complete responders (CR) and 41% of partial responders (PR) had increases in CA125 from baseline to cycle 1. Increases in CA125 were also seen in topotecan-treated patients; however, fewer patients had increases (20% and 8%, respectively). Overall, 15% of responding patients (CR + PR) receiving PLD and 6% receiving topotecan had elevated CA125 after two cycles of therapy. For those patients achieving a partial response, 19% of PLD-treated patients and 8% of topotecan-treated patients had CA125 levels above baseline at cycle 2. CONCLUSIONS: Considerable intrapatient variation in CA125 values is present among responding patients. Early increases in CA125 may not predict ultimate outcome, especially in PLD-treated patients.

CA-125 response in patients with recurrent ovarian or primary peritoneal cancer treated with pegylated liposomal doxorubicin or topotecan.

OBJECTIVE: Recent additions of novel chemotherapeutics, such as pegylated liposomal doxorubicin (PLD) and topotecan (TPT), have provided clinicians with multiple options for treating recurrent ovarian cancer. Evaluating treatment response in patients without radiographic or physically measurable disease is problematic, thereby CA-125 values may be the only available objective criteria. It has been advocated that several cycles of novel agents are required prior to an observed CA-125 response. In this study, we sought to gain insight into response patterns regarding CA-125 in responders vs. non-responders and to determine whether specific "cut-off" values could help predict ultimate clinical response. METHODS: Patients with recurrent ovarian cancer who received either single agent PLD, TPT, or both were included. CA-125 levels were evaluated prior to initiation of chemotherapy and thereafter for each additional cycle. The Rustin criteria were utilized to evaluate CA-125 response. RESULTS: Fifty-four of 120 patients were judged to be responders. When comparing responders to non-responders, as expected, the majority of responders demonstrated a decrease after each of the first 4 cycles. However, nearly 50% of responders who received PLD demonstrated an increase in CA-125 after cycle 1. There were no responders who demonstrated two successive rises in CA-125. CONCLUSION: The majority of patients with recurrent ovarian cancer who will ultimately manifest a CA-125 response to novel agents, such as TPT or PLD, will demonstrate a decrease following each cycle. An initial increase in CA-125 should not mandate discontinuation of current therapy, but a successive rise over two or more cycles reliably predicts that a treatment response ultimately is unlikely.