A phase 2 randomized, double-blind, placebo-controlled study of the safety and efficacy of talactoferrin in patients with severe sepsis.

OBJECTIVES: Lactoferrin is a glycoprotein with anti-infective and anti-inflammatory properties found in secretions and immune cells. Talactoferrin alfa, a recombinant form of human lactoferrin, has similar properties and plays an important role in maintaining the gastrointestinal mucosal barrier integrity. In experimental animal models, administration of talactoferrin reduces translocation of bacteria from the gut into the systemic circulation and mortality from sepsis. Our objective was to determine if talactoferrin could reduce 28-day all-cause mortality in patients with severe sepsis and to assess its safety. DESIGN: Prospective, randomized, double-blind, placebo-controlled, multicenter phase 2 trial. SETTING: Adult ICUs and emergency departments in the United States. PATIENTS: One hundred ninety-four adults within 24 hrs of the onset of severe sepsis. INTERVENTIONS: Enterally administered talactoferrin 1.5g or placebo every 8 hrs for up to 28 days or until discharge from the ICU. MEASUREMENTS AND MAIN RESULTS: Modified intention-to-treat analysis was used to assess the primary (28-day all-cause mortality) and secondary endpoints. The all-cause mortality at 28 days was 26.9% in the placebo group and 14.4% in the talactoferrin group (two-sided p = 0.052), representing a 12.5% absolute and a 46.5% relative reduction in mortality, meeting the protocol-specified primary endpoint. Reduction in all cause mortality was sustained at 6 months (p = 0.039). These reductions in mortality were observed across a wide spectrum of subgroups. The drug was well tolerated with a safety profile similar to that of placebo. CONCLUSIONS: Enteral administration of talactoferrin reduced 28-day all-cause mortality in patients with severe sepsis. This reduction in mortality was sustained at 6 months. Talactoferrin was very well tolerated.

A novel LacZ reporter mouse reveals complex regulation of the progesterone receptor promoter during mammary gland development.

To further our understanding of progesterone (P) as an endocrine mammogen, a PR(lacz) knockin mouse was generated in which the endogenous progesterone receptor (PR) promoter directly regulated lacZ reporter expression. The PR(lacz) mouse revealed PR promoter activity was restricted to the epithelial compartment during the prenatal and postnatal stages of mammary gland development. At puberty, PR promoter activity was unexpectedly robust and restricted to the body cells within the terminal end buds and to the luminal epithelial cells in the subtending ducts. In the adult, the preferential localization of PR(lacz) positive cells to the distal regions of ductal side branches provided a cellular context to the recognized mandatory role of P in ductal side-branching, and segregation of these cells from cells that undergo proliferation supported an intraepithelial paracrine mode of action for P in branching morphogenesis. Toward the end of pregnancy, the PR(lacz) mouse disclosed a progressive attenuation in PR promoter activity, supporting the postulate that the preparturient removal of the proliferative signal of P is a prerequisite for the emergence of a functional lactating mammary gland. The data suggest that PR expression before pregnancy is to ensure the specification and spatial organization of ductal and alveolar progenitor cell lineages, whereas abrogation of PR expression before lactation is required to enable terminal differentiation of the mammary gland.

Progesterone involvement in breast development and tumorigenesis--as revealed by progesterone receptor "knockout" and "knockin" mouse models.

In light of recent clinical trials, the debate concerning the risks and benefits of progestin-based postmenopausal hormone replacement therapy (HRT) has reached a renewed level of urgency. Irrespective of the position taken, the consensus is that more basic research needs to be performed to address progesterone's fundamental role in mammary development and tumorigenesis. Towards this end, the progesterone receptor knockout (PRKO) mouse demonstrated that progesterone is essential for pregnancy-associated mammary gland ductal side-branching and alveologenesis and that these morphological changes are dependent on progesterone-induced mammary epithelial proliferation. Importantly, the PRKO mouse showed that the progesterone-proliferative signal significantly contributes to mammary tumor susceptibility in an established mammary tumor model. Insight into the cellular mechanism(s) by which progesterone affects mammary morphogenesis has been disclosed by a new PR-LacZ knockin mouse, which revealed that PR's spatial expression pattern undergoes precise choreographed distributional changes that precede key stages in postnatal mammary development. In the case of early pregnancy, the segregation of cells undergoing progesterone-induced proliferation from those that express PR implicates a paracrine mode of action for progesterone-induced mammary epithelial proliferation, whereas the preparturient decline of PR expression underscores the need to remove this signal for full functional differentiation of this tissue. Our findings support the proposal that the mammary gland's normal response to the progesterone-signal is dependent upon specific spatial organizational patterns of PR expression and that derailment in these cellular processes may contribute to abnormal mammary development, including cancer. This review concludes by emphasizing the need to identify the downstream molecular targets that mediate progesterone's effects in this tissue. Identification of such targets will not only enhance our mechanistic understanding of progesterone's role in mammary development and cancer, but may also facilitate the formulation of new design strategies in breast cancer diagnosis and/or treatment.

Randomized, double-blind, placebo-controlled phase II study of single-agent oral talactoferrin in patients with locally advanced or metastatic non-small-cell lung cancer that progressed after chemotherapy.

PURPOSE: To investigate the activity and safety of oral talactoferrin (TLF) in patients with stages IIIB to IV non-small-cell lung cancer (NSCLC) for whom one or two prior lines of systemic anticancer therapy had failed. PATIENTS AND METHODS: Patients (n = 100) were randomly assigned to receive either oral TLF (1.5 g in 15 mL phosphate-based buffer) or placebo (15 mL phosphate-based buffer) twice per day in addition to supportive care. Oral TLF or placebo was administered for a maximum of three 14-week cycles with dosing for 12 consecutive weeks followed by 2 weeks off. The primary objective was overall survival (OS) in the intent-to-treat (ITT) patient population. Secondary objectives included progression-free survival (PFS), disease control rate (DCR), and safety. RESULTS: TLF was associated with improvement in OS in the ITT patient population, meeting the protocol-specified level of significance of a one-tailed P = .05. Compared with the placebo group, median OS increased by 65% in the TLF group (3.7 to 6.1 months; hazard ratio, 0.68; 90% CI, 0.47 to 0.98; P = .04 with one-tailed log-rank test). Supportive trends were also observed for PFS and DCR. TLF was well tolerated and, generally, there were fewer adverse events (AEs) and grade ≥ 3 AEs reported in the TLF arm. AEs were consistent with those expected in late-stage NSCLC. CONCLUSION: TLF demonstrated an apparent improvement in OS in patients with stages IIIB to IV NSCLC for whom one or two prior lines of systemic anticancer therapy had failed and was well tolerated. These results should be confirmed in a global phase III trial.

Progesterone's role in mammary gland development and tumorigenesis as disclosed by experimental mouse genetics.

The progesterone receptor knockout mouse demonstrated progesterone's importance to parity-induced mammary tertiary branching and lobuloalveologenesis. Because early parity provides significant protection against breast cancer whereas prolonged exposure to premenopausal ovarian progesterone (or to postmenopausal supplementations thereof) has been linked to breast cancer risk, this steroid can be considered to exhibit contrasting roles in breast cancer etiology. This review describes the important mouse models that have contributed to our understanding of progesterone's role in mammary gland development and neoplasia. We conclude by emphasising the urgent need to identify the molecular targets of the progesterone receptor, and to determine whether these targets are modulated differently by the progesterone receptor isoforms (A and B) during mammary morphogenesis and tumorigenesis.