A phase II study of aflibercept in patients with advanced epithelial ovarian cancer and symptomatic malignant ascites

A phase II study of aflibercept in patients with advanced epithelial ovarian cancer and symptomatic malignant ascites

Objective 
The recombinant fusion protein, aflibercept binds and neutralizes vascular endothelial growth factor (VEGF) A, B and placental growth factor (PlGF). Aflibercept inhibits ascites formation and reduces tumor burden in an ovarian cancer model. This open-label, single-arm, multicenter phase II study assessed the efficacy and safety of aflibercept in patients with advanced chemo-resistant epithelial ovarian cancer and symptomatic malignant ascites.

Methods 
Patients who required ≥3 previous paracenteses at 1-4 paracenteses per month received intravenous aflibercept 4mg/kg every 2weeks. The primary endpoint was repeat paracentesis response rate (RPRR), with response defined as at least a two-fold increase in time to repeat paracentesis compared with the baseline interval.

Results 
Ten out of 16 enrolled patients achieved a response; the RPRR was 62.5% (95% CI 35.4%–84.8%). Aflibercept was considered effective based on a hypothesis that the RPRR was ≥60%. Median time to repeat paracentesis was 76.0 (95% CI 64.0–178.0) days, which was 4.5 times longer than the baseline interval (16.8days). Median progression-free survival was 59.5 (95% CI 41.0–83.0) days. Twelve patients experienced adverse events considered related to aflibercept treatment including hypertension (7 patients), headache, anorexia, and dysphonia (3 patients each). Two patients experienced Grade 3/4 treatment-related adverse events (Grade 3 hypertension and weight loss in one patient, Grade 3 intestinal perforation in one patient).

Conclusion 
Aflibercept 4mg/kg every 2weeks was effective at controlling malignant ascites, reducing the interval between repeat paracenteses. The safety profile was consistent with that reported for anti-VEGF agents.

Humoral response to catumaxomab correlates with clinical outcome: Results of the pivotal phase II/III study in patients with malignant ascites. (compared to paracentesis)

Humoral response to catumaxomab correlates with clinical outcome: Results of the pivotal phase II/III study in patients with malignant ascites.

The trifunctional antibody catumaxomab is a targeted immunotherapy for the intraperitoneal treatment of malignant ascites.

In a Phase II/III trial in cancer patients (n = 258) with malignant ascites, catumaxomab showed a clear clinical benefit vs. paracentesis and had an acceptable safety profile. Human antimouse antibodies (HAMAs), which could be associated with beneficial humoral effects and prolonged survival, may develop against catumaxomab as it is a mouse/rat antibody. This post hoc analysis investigated whether there was a correlation between the detection of HAMAs 8 days after the fourth catumaxomab infusion and clinical outcome. HAMA-positive and HAMA-negative patients in the catumaxomab group and patients in the control group were analyzed separately for all three clinical outcome measures (puncture-free survival, time to next puncture and overall survival) and compared to each other. There was a strong correlation between humoral response and clinical outcome: patients who developed HAMAs after catumaxomab showed significant improvement in all three clinical outcome measures vs. HAMA-negative patients. In the overall population in HAMA-positive vs. HAMA-negative patients, median puncture-free survival was 64 vs. 27 days (p < 0.0001; HR 0.330), median time to next therapeutic puncture was 104 vs. 46 days (p = 0.0002; HR 0.307) and median overall survival was 129 vs. 64 days (p = 0.0003; HR 0.433).

Similar differences between HAMA-positive and HAMA-negative patients were seen in the ovarian, nonovarian and gastric cancer subgroups.

In conclusion, HAMA development may be a biomarker for catumaxomab response and patients who developed HAMAs sooner derived greater benefit from catumaxomab treatment.

short abstract: Gynecological cancer: True progress in ovarian cancer or just the tip of the iceberg?

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 Gynecological cancer: True progress in ovarian cancer or just the tip of the iceberg?

Lisa Hutchinson

"Abstract

Development of malignant ascites is common in patients with ovarian cancer, and few therapeutic options exist for women with ascites whose tumors become resistant to chemotherapy. Furthermore, in such patients symptom palliation options are limited, and the few available treatments are unpleasant and can result in the need for paracentesis."