Purpose: Bevacizumab, a recombinant humanized monoclonal antibody against vascular endothelial growth factor-A (VEGF-A), has clinical activity in multiple tumor types. We conducted a phase II trial to assess the activity and tolerability of single-agent bevacizumab in recurrent or persistent endometrial cancer (EMC). Patients and Methods: Eligible patients had persistent or recurrent EMC after receiving one to two prior cytotoxic regimens, measurable disease, and Gynecologic Oncology Group performance status of ≤ 2. Treatment consisted of bevacizumab 15 mg/kg intravenously every 3 weeks until disease progression or prohibitive toxicity. VEGF-A was assessed by immunohistochemistry in archival tumor and by enzyme-linked immunosorbent assay in pretreatment plasma. Primary end points were progression-free survival (PFS) at 6 months and overall response rate. Results: Fifty-six patients were enrolled. Fifty-two patients were eligible and evaluable. Median age was 62 years, and prior treatment consisted of one or two regimens in 33 (63.5%) and 19 (36.5%) patients, respectively. Twenty-nine patients (55.8%) received prior radiation. Adverse events were consistent with those expected with bevacizumab treatment. No GI perforations or fistulae were seen. Seven patients (13.5%) experienced clinical responses (one complete response and six partial responses; median response duration, 6.0 months), and 21 patients (40.4%) survived progression free for at least 6 months. Median PFS and overall survival times were 4.2 and 10.5 months, respectively. Suggested associations were observed between high VEGF-A and adjusted hazard of death or tumor response when evaluated in tumor/plasma or plasma, respectively. Conclusion: Bevacizumab is well tolerated and active based on PFS at 6 months in recurrent or persistent EMC and warrants further investigation.

Preeclampsia, a cardiovascular disorder of late pregnancy, is characterized as a low-renin hypertensive state relative to normotensive pregnancy. Because other nonpregnant low-renin hypertensive disorders often exhibit and are occasionally dependent on elevated arginine vasopressin (AVP) secretion, we hypothesized a possible use for plasma AVP measurements in the prediction of preeclampsia. Copeptin is an inert prosegment of AVP that is secreted in a 1:1 molar ratio and exhibits a substantially longer biological half-life compared with AVP, rendering it a clinically useful biomarker of AVP secretion. Copeptin was measured throughout pregnancy in maternal plasma from preeclamptic and control women. Maternal plasma copeptin was significantly higher throughout preeclamptic pregnancies versus control pregnancies. While controlling for clinically significant confounders (age, body mass index, chronic essential hypertension, twin gestation, diabetes mellitus, and history of preeclampsia) using multivariate regression, the association of higher copeptin concentration and the development of preeclampsia remained significant. Receiver operating characteristic analyses reveal that as early as the sixth week of gestation, elevated maternal plasma copeptin concentration is a highly significant predictor of preeclampsia throughout pregnancy. Finally, chronic infusion of AVP during pregnancy (24 ng per hour) is sufficient to phenocopy preeclampsia in C57BL/6J mice, causing pregnancy-specific hypertension, renal glomerular endotheliosis, proteinuria, and intrauterine growth restriction. These data implicate AVP release as a novel predictive biomarker for preeclampsia very early in pregnancy, identify chronic AVP infusion as a novel and clinically relevant model of preeclampsia in mice, and are consistent with a potential causative role for AVP in preeclampsia in humans.