Phase Ib Study of Unesbulin (PTC596) Plus Dacarbazine for the Treatment of Locally Recurrent, Unresectable or Metastatic, Relapsed or Refractory Leiomyosarcoma.

PURPOSE: This multicenter, single-arm, open-label, phase Ib study was designed to determine the recommended phase II dose (RP2D) and to evaluate the safety and preliminary efficacy of unesbulin plus dacarbazine (DTIC) in patients with advanced leiomyosarcoma (LMS). PATIENTS AND METHODS: Adult subjects with locally advanced, unresectable or metastatic, relapsed or refractory LMS were treated with escalating doses of unesbulin orally twice per week in combination with DTIC 1,000 mg/m2 intravenously (IV) once every 21 days. The time-to-event continual reassessment method was used to determine the RP2D on the basis of dose-limiting toxicities (DLTs) assessed during the first two 21-day treatment cycles. All explored doses of unesbulin (200 mg up to 400 mg) were in combination with DTIC. An expansion cohort was enrolled to evaluate the safety and efficacy of unesbulin at the RP2D. RESULTS: Unesbulin 300 mg administered orally twice per week in combination with DTIC 1,000 mg/m2 IV once every 21 days was identified as the RP2D. On the basis of data from 27 subjects who were deemed DLT-evaluable, toxicity was higher in the unesbulin 400 mg group, with three of four subjects (75%) experiencing DLTs versus one of four subjects (25%) in the 200 mg group and three of 19 subjects (15.8%) in the 300 mg group. The most commonly reported DLTs and treatment-related grade 3 and 4 adverse events were thrombocytopenia and neutropenia. At the RP2D, seven subjects who were efficacy evaluable achieved partial response for an objective response rate of 24.1%. CONCLUSION: Unesbulin 300 mg twice per week plus DTIC 1,000 mg/m2 once every 21 days was identified as the RP2D, demonstrating a favorable benefit-risk profile in a heavily pretreated population of adults with advanced LMS.

Efficacy and safety of oral conivaptan: a V1A/V2 vasopressin receptor antagonist, assessed in a randomized, placebo-controlled trial in patients with euvolemic or hypervolemic hyponatremia.

CONTEXT: Hyponatremia [serum sodium concentration ([Na(+)]), <135 mEq/liter] is the most common fluid and electrolyte abnormality among hospitalized patients. It is frequently caused by the inappropriate release of arginine vasopressin. OBJECTIVE: The objective of this study was to evaluate the efficacy and safety of oral conivaptan, a vasopressin V(1A)/V(2) receptor antagonist, in patients with euvolemic or hypervolemic hyponatremia. DESIGN: The study design was a 5-d placebo-controlled, randomized, double-blind study. SETTING: The study was performed at a hospital. INTERVENTION: Oral conivaptan (40 or 80 mg/d) or placebo was given in two divided doses. PATIENTS: Seventy-four patients (average baseline serum [Na(+)], 115 to <130 mEq/liter) were studied. MAIN OUTCOME MEASURE: The main outcome measure was the change from baseline in serum [Na(+)] area under the curve. RESULTS: The least-squares mean change from baseline in the serum [Na(+)] area under the curve with conivaptan (40 and 80 mg/d) was 2.0-fold (P = 0.03) and 2.5-fold (P < 0.001) greater, respectively, than that with placebo. The median time to achieve a confirmed increase in serum [Na(+)] of 4 mEq/liter or more from baseline was 71.7 h for placebo, 27.5 h for 40 mg/d conivaptan (P = 0.044), and 12.1 h for 80 mg/d conivaptan (P = 0.002). The mean total times during which patients had a serum [Na(+)] level of 4 mEq/liter or more above baseline were 46.5, 69.8, and 88.8 h (P = 0.001), respectively. The least-squares mean change in serum [Na(+)] from baseline to end of treatment was 3.4 mEq/liter for placebo, 6.4 mEq/liter for 40 mg/d conivaptan, and 8.2 mEq/liter for 80 mg/d conivaptan (P = 0.002). A confirmed normal serum [Na(+)] (>/=135 mEq/liter) or increase of 6 mEq/liter or more was observed in 48% of patients given placebo, 71% given 40 mg/d conivaptan, and 82% given 80 mg/d conivaptan (P = 0.014). Headache, hypotension, nausea, constipation, and postural hypotension were the most common adverse events. CONCLUSION: Oral conivaptan (40 and 80 mg/d) was well tolerated and efficacious in correcting serum [Na(+)] in hyponatremia.

Determinants of plasma leptin concentration in postmenopausal women.

This investigation examined the influence of hormone replacement therapy on plasma leptin concentrations in postmenopausal women and sought to determine if a relationship existed between plasma leptin, the thermoregulatory cytokine interleukin-1 (IL-1), and basal body temperature. Twenty-two women (54-71 years of age) were studied: eight were not taking hormone replacement, seven took oral estrogen only, and seven took oral estrogen plus progestin. Morning oral temperature, plasma leptin concentration, and mononuclear cell secretion of IL-1beta, IL-1 receptor antagonist (IL-1Ra), and soluble IL-1 receptor type II (sIL-1RII) were measured. Plasma leptin concentrations were not affected by hormone replacement therapy, but were inversely related to years since menopause (R = -0.48, P = 0.02) and were proportional to IL-1 activity (the balance of IL-1beta/IL-1Ra secretion, R = 0.69, P = 0.001). Moreover, morning oral temperature was positively related to plasma leptin (P = 0.03), after stratifying by progestin intake. These results support the concept that basal body temperature is regulated by a network of endocrine and immune mediators that are significantly influenced by age.

Hormonal modulation of interleukin-6, tumor necrosis factor and associated receptor secretion in postmenopausal women.

Hormone replacement therapy (HRT) reduces the risk for osteoporosis but transiently increases cardiovascular risk for some postmenopausal women. This study investigated the hypothesis that these risks are associated with HRT-induced changes in mononuclear cell secretion of interleukin-6 (IL-6), tumor necrosis factor alpha (TNF-alpha), and associated soluble receptors. Compared to the untreated condition (n=8), estrogen therapy (n=7) and estrogen+progestin therapy (n=7) both caused 2-fold elevations in TNF-alpha secretion. IL-6 secretion was increased (48%, P=0.04) only by estrogen+progestin therapy. Although soluble receptor secretion was not different among groups, soluble TNF receptor type I and IL-6 receptor secretion were inversely related to plasma follicle stimulating hormone (P<0.05). Both therapies reduced plasma osteocalcin (a marker for osteoporosis) by approximately 50% (P<0.002). Plasma C-reactive protein (CRP, a marker for cardiovascular risk) was 3-fold higher in women receiving only estrogen, compared to untreated women (P=0.01), and twice as high as those receiving estrogen+ progestin (P=0.045). Simple linear relationships were not observed between cytokine secretion and these markers, but a significant HRT/TNF-alpha interaction with osteocalcin (P=0.022) and an HRT/IL-6 interaction with CRP (P =0.016) indicated more complex relationships between hormone replacement, cytokine activity, and health risks associated with menopause.

Estrogen has opposing effects on vascular reactivity in obese, insulin-resistant male Zucker rats.

We hypothesized that estradiol treatment would improve vascular dysfunction commonly associated with obesity, hyperlipidemia, and insulin resistance. A sham operation or 17beta-estradiol pellet implantation was performed in male lean and obese Zucker rats. Maximal vasoconstriction (VC) to phenylephrine (PE) and potassium chloride was exaggerated in control obese rats compared with lean rats, but estradiol significantly attenuated VC in the obese rats. Estradiol reduced the PE EC50 in all groups. This effect was cyclooxygenase independent, because preincubation with indomethacin reduced VC response to PE similarly in a subset of control and estrogen-treated lean rats. Endothelium-independent vasodilation (VD) to sodium nitroprusside was similar among groups, but endothelium-dependent VD to ACh was significantly impaired in obese compared with lean rats. Estradiol improved VD in lean and obese rats by decreasing EC50 but impaired function by decreasing maximal VD. The shift in EC50 corresponded to an upregulation in nitric oxide synthase III protein expression in the aorta of the estrogen-treated obese rats. In summary, estrogen treatment improves vascular function in male insulin-resistant, obese rats, partially via an upregulation of nitric oxide synthase III protein expression. These effects are counteracted by adverse factors, such as hyperlipidemia and, potentially, a release of an endothelium-derived contractile agent.