Pharmacodynamic effects and mechanisms of resistance to vemurafenib in patients with metastatic melanoma.

PURPOSE To assess pharmacodynamic effects and intrinsic and acquired resistance mechanisms of the BRAF inhibitor vemurafenib in BRAF(V600)-mutant melanoma, leading to an understanding of the mechanism of action of vemurafenib and ultimately to optimization of metastatic melanoma therapy. METHODS In the phase II clinical study NP22657 (BRIM-2), patients received oral doses of vemurafenib (960 mg twice per day). Serial biopsies were collected to study changes in mitogen-activated protein kinase (MAPK) signaling, cell-cycle progression, and factors causing intrinsic or acquired resistance by immunohistochemistry, DNA sequencing, or somatic mutation profiling.

Two-stage designs for phase II cancer trials with ordinal responses.

A common approach to the design of phase II clinical trials in oncology is to conduct a two-stage trial so as to control type I and type II error rates. A number of researchers have proposed methods for the design of such trials when the response can take one of a number of ordered values such as tumor response, stable disease or progressive disease. In this case, the problem may be formulated as that of testing a complex null hypothesis.

Open-label phase II study evaluating the efficacy and safety of two doses of pertuzumab in castrate chemotherapy-naive patients with hormone-refractory prostate cancer.

Purpose: To determine the prostate-specific antigen (PSA) 50% decline rate within 24 weeks of starting treatment with single-agent pertuzumab in castrate patients with hormone-refractory prostate cancer (HRPC).

Patients And Methods: Two independent Simon's two-stage designs were used to evaluate two doses of pertuzumab administered intravenously once every 3 weeks. An interim analysis of the first 23 assessable patients in the first cohort treated at 420 mg (loading dose of 840 mg) allowed termination of additional enrollment if three patients had a 50% decline in PSA after all patients had completed at least three cycles of therapy or withdrew due to insufficient therapeutic response, death, or study-related toxicity before completing three cycles.

Daclizumab to prevent rejection after cardiac transplantation.

Background: Daclizumab, a humanized monoclonal antibody against the interleukin-2 receptor, reduced the risk of rejection without increasing the risk of infection among renal-transplant recipients and, in a single-center trial, among cardiac-transplant recipients. We conducted a multicenter, placebo-controlled, double-blind study to confirm these results in cardiac-transplant patients.

Methods: We randomly assigned 434 recipients of a first cardiac transplant treated with standard immunosuppression (cyclosporine, mycophenolate mofetil, and corticosteroids) to receive five doses of daclizumab or placebo.

Orlistat maintains biliary lipid composition and hepatobiliary function in obese subjects undergoing moderate weight loss.

Objectives: Orlistat, an intestinal lipase inhibitor, has recently been approved by the US Food and Drug Administration for treatment of obesity. The effects of orlistat on hepatobiliary function have not been previously defined. A 4 wk study was performed involving modest weight loss in obese subjects to observe any short-term hepatobiliary responses that occur after initiating treatment with orlistat and a hypocaloric diet.

Ceftriaxone compared with doxycycline for the treatment of acute disseminated Lyme disease.

Background: Localized Lyme disease, manifested by erythema migrans, is usually treated with oral doxycycline or amoxicillin. Whether acute disseminated Borrelia burgdorferi infection should be treated differently from localized infection is unknown.

Methods: We conducted a prospective, open-label, randomized, multicenter study comparing parenteral ceftriaxone (2 g once daily for 14 days) with oral doxycycline (100 mg twice daily for 21 days) in patients with acute disseminated B.