Predictors of placebo response in three large clinical trials of the V1a receptor antagonist balovaptan in autism spectrum disorder.

High rates of placebo response are increasingly implicated in failed autism spectrum disorder (ASD) clinical trials. Despite this, there are limited investigations of placebo response in ASD. We sought to identify baseline predictors of placebo response and quantify their influence on clinical scales of interest for three harmonized randomized clinical trials of balovaptan, a V1a receptor antagonist. We employed a two-step approach to identify predictors of placebo response on the Vineland-II two-domain composite (2DC) (primary outcome and a caregiver measure) and Clinical Global Impression (CGI) scale (secondary outcome and a clinician measure). The initial candidate predictor set of variables pertained to participant-level, site-specific, and protocol-related factors. Step 1 aimed to identify influential predictors of placebo response using Least Absolute Shrinkage and Selection Operator (LASSO) regression, while Step 2 quantified the influence of predictors via linear regression. Results were validated through statistical bootstrapping approaches with 500 replications of the analysis dataset. The pooled participant-level dataset included individuals with ASD aged 5 to 62 years (mean age 21 [SD 10]), among which 263 and 172 participants received placebo at Weeks 12 and 24, respectively. Although no influential predictors were identified for CGI, findings for Vineland-II 2DC are robust and informative. Decreased placebo response was predicted by higher baseline Vineland-II 2DC (i.e., more advanced adaptive function), longer trial duration, and European (vs United States) sites, while increased placebo response was predicted by commercial (vs academic) sites, attention deficit hyperactivity disorder and depression. Identification of these factors may be useful in anticipating and mitigating placebo response in drug development efforts in ASD and across developmental and psychiatric conditions.

Vanucizumab mode of action: Serial biomarkers in plasma, tumor, and skin-wound-healing biopsies.

Vanucizumab is a novel bispecific antibody inhibiting vascular endothelial growth factor (VEGF-A) and angiopoietin-2 (Ang-2) that demonstrated safety and anti-tumor activity in part I of a phase I study of 42 patients with advanced solid tumors. Part II evaluated the pharmacodynamic effects of vanucizumab 30 or 15 mg/kg every 2 weeks in 32 patients. Serial plasma samples, paired tumor, and skin-wound-healing biopsies were taken over 29 days to evaluate angiogenic markers. Vanucizumab was associated with marked post-infusion reductions in circulating unbound VEGF-A and Ang-2. By day 29, tumor samples revealed mean reductions in density of microvessels (-32.2%), proliferating vessels (-47.9%) and Ang-2 positive vessels (-62.5%). Skin biopsies showed a mean reduction in density of microvessels (-49.0%) and proliferating vessels (-25.7%). Gene expression profiling of tumor samples implied recruitment and potential activation of lymphocytes. Biopsies were safely conducted. Vanucizumab demonstrated a consistent biological effect on vascular-related biomarkers, confirming proof of concept. Skin-wound-healing biopsies were a valuable surrogate for studying angiogenesis-related mechanisms.

The McCAVE Trial: Vanucizumab plus mFOLFOX-6 Versus Bevacizumab plus mFOLFOX-6 in Patients with Previously Untreated Metastatic Colorectal Carcinoma (mCRC).

BACKGROUND: Bevacizumab, a VEGF-A inhibitor, in combination with chemotherapy, has proven to increase progression-free survival (PFS) and overall survival in multiple lines of therapy of metastatic colorectal cancer (mCRC). The angiogenic factor angiopoetin-2 (Ang-2) is associated with poor prognosis in many cancers, including mCRC. Preclinical models demonstrate improved activity when inhibiting both VEGF-A and Ang-2, suggesting that the dual VEGF-A and Ang-2 blocker vanucizumab (RO5520985 or RG-7221) may improve clinical outcomes. This phase II trial evaluated the efficacy of vanucizumab plus modified (m)FOLFOX-6 (folinic acid (leucovorin), fluorouracil (5-FU) and oxaliplatin) versus bevacizumab/mFOLFOX-6 for first-line mCRC. PATIENTS AND METHODS: All patients received mFOLFOX-6 and were randomized 1:1 to also receive vanucizumab 2,000 mg or bevacizumab 5 mg/kg every other week. Oxaliplatin was given for eight cycles; other agents were continued until disease progression or unacceptable toxicity for a maximum of 24 months. The primary endpoint was investigator-assessed PFS. RESULTS: One hundred eighty-nine patients were randomized (vanucizumab, n = 94; bevacizumab, n = 95). The number of PFS events was comparable (vanucizumab, n = 39; bevacizumab, n = 43). The hazard ratio was 1.00 (95% confidence interval, 0.64-1.58; p = .98) in a stratified analysis based on number of metastatic sites and region. Objective response rate was 52.1% and 57.9% in the vanucizumab and bevacizumab arm, respectively. Baseline plasma Ang-2 levels were prognostic in both arms but not predictive for treatment effects on PFS of vanucizumab. The incidence of adverse events of grade ≥3 was similar between treatment arms (83.9% vs. 82.1%); gastrointestinal perforations (10.8% vs. 8.4%) exceeded previously reported rates in this setting. Hypertension and peripheral edema were more frequent in the vanucizumab arm. CONCLUSION: Vanucizumab/mFOLFOX-6 did not improve PFS and was associated with increased rates of antiangiogenic toxicity compared with bevacizumab/mFOLFOX-6. Our results suggest that Ang-2 is not a relevant therapeutic target in first-line mCRC. IMPLICATIONS FOR PRACTICE: This randomized phase II study demonstrates that additional angiopoietin-2 (Ang-2) inhibition does not result in superior benefit over anti-VEGF-A blockade alone when each added to standard chemotherapy. Moreover, the performed pharmacokinetic and pharmacodynamic analysis revealed that vanucizumab was bioavailable and affected its intended target, thereby strongly suggesting that Ang-2 is not a relevant therapeutic target in the clinical setting of treatment-naïve metastatic colorectal cancer. As a result, the further clinical development of the dual VEGF-A and Ang-2 inhibitor vanucizumab was discontinued.

First-in-Human Phase I Study of Single-agent Vanucizumab, A First-in-Class Bispecific Anti-Angiopoietin-2/Anti-VEGF-A Antibody, in Adult Patients with Advanced Solid Tumors.

Purpose: Vanucizumab is an investigational antiangiogenic, first-in-class, bispecific mAb targeting VEGF-A and angiopoietin-2 (Ang-2). This first-in-human study evaluated the safety, pharmacokinetics, pharmacodynamics, and antitumor activity of vanucizumab in adults with advanced solid tumors refractory to standard therapies.Experimental Design: Patients received escalating biweekly (3-30 mg/kg) or weekly (10-30 mg/kg) intravenous doses guided by a Bayesian logistic regression model with overdose control.Results: Forty-two patients were treated. One dose-limiting toxicity, a fatal pulmonary hemorrhage from a large centrally located mediastinal mass judged possibly related to vanucizumab, occurred with the 19 mg/kg biweekly dose. Arterial hypertension (59.5%), asthenia (42.9%), and headache (31%) were the most common toxicities. Seventeen (41%) patients experienced treatment-related grade ≥3 toxicities. Toxicity was generally higher with weekly than biweekly dosing. A MTD of vanucizumab was not reached in either schedule. Pharmacokinetics were dose-linear with an elimination half-life of 6-9 days. All patients had reduced plasma levels of free VEGF-A and Ang-2; most had reductions in KTRANS (measured by dynamic contrast-enhanced MRI). Two patients (renal cell and colon cancer) treated with 30 mg/kg achieved confirmed partial responses. Ten patients were without disease progression for ≥6 months. A flat-fixed 2,000 mg biweekly dose (phamacokinetically equivalent to 30 mg/kg biweekly) was recommended for further investigation.Conclusions: Biweekly vanucizumab had an acceptable safety and tolerability profile consistent with single-agent use of selective inhibitors of the VEGF-A and Ang/Tie2 pathway. Vanucizumab modulated its angiogenic targets, impacted tumor vascularity, and demonstrated encouraging antitumor activity in this heterogeneous population. Clin Cancer Res; 24(7); 1536-45. ©2017 AACR.

Differential effects of fenofibrate and extended-release niacin on high-density lipoprotein particle size distribution and cholesterol efflux capacity in dyslipidemic patients.

BACKGROUND: The effectiveness of therapies that raise high-density lipoprotein cholesterol (HDL-C) to lower cardiovascular disease risk is currently under debate, and further research into the relationship between HDL-C and function is required. OBJECTIVE: o investigate whether 2 established HDL-C-raising therapies had differential effects on parameters of high-density lipoprotein (HDL) quality and function, such as HDL particle profile and cholesterol efflux capacity (CEC), in patients with dyslipidemia. METHODS AND RESULTS: Sixty-six patients with dyslipidemia, 24 with low HDL-C levels (<40 mg/dL) and 42 with normal HDL-C levels (40-59 mg/dL), were treated for 6 weeks with fenofibrate (160 mg/d) or extended-release (ER) niacin (0.5 g/d for 3 weeks, then 1 g/d) with 4 weeks of washout between treatments. Lipoprotein particle size distribution was determined using nuclear magnetic resonance, and pathway-specific serum CECs were assessed in J774 macrophages, hepatoma, and Chinese hamster ovary-human adenosine triphosphate-binding cassette transporter G1 cells. Comparable increases in HDL-C and apolipoprotein A-I levels were seen with fenofibrate and ER niacin. There was a shift toward larger HDL, predominantly to medium-size HDL particles for fenofibrate (+209%) and to large HDL particles for ER niacin (+221%). Minor changes in serum CECs were observed with fenofibrate and ER niacin for all the efflux pathways measured. Small increases in plasma cholesteryl ester transfer protein and lecithin: cholesterol acyltransferase concentrations, and decreases in cholesteryl ester transfer protein activity were seen with both drugs. CONCLUSIONS: Fenofibrate and ER niacin increased plasma HDL-C level similarly, but modulated HDL particle size distribution differently; however, these changes did not result in differential effects on serum CECs.

Xanthophylls, phytosterols and pre-ß1-HDL are differentially affected by fenofibrate and niacin HDL-raising in a cross-over study.

Fenofibrate and extended-release (ER) niacin similarly raise high-density lipoprotein cholesterol (HDL-C) concentration but their effects on levels of potent plasma antioxidant xanthophylls (lutein and zeaxanthin) and phytosterols obtained from dietary sources, and any relationship with plasma lipoproteins and pre-ß1-HDL levels, have not been investigated. We studied these parameters in 66 dyslipidemic patients treated for 6 week with fenofibrate (160 mg/day) or ER-niacin (0.5 g/day for 3 week, then 1 g/day) in a cross-over study. Both treatments increased HDL-C (16 %) and apolipoprotein (apo) A-I (7 %) but only fenofibrate increased apoA-II (28 %). Lutein and zeaxanthin levels were unaffected by fenofibrate but inversely correlated with percentage change in apoB and low-density lipoprotein cholesterol and positively correlated with end of treatment apoA-II. ApoA-II in isolated HDL in vitro bound more lutein than apoA-I. Xanthophylls were increased by ER-niacin (each ~30 %) without any correlation to lipoprotein or apo levels. Only fenofibrate markedly decreased plasma markers of cholesterol absorption; pre-ß1-HDL was significantly decreased by fenofibrate (-19 %, p < 0.0001), with little change (3.4 %) for ER-niacin. Although fenofibrate and ER-niacin similarly increased plasma HDL-C and apoA-I, effects on plasma xanthophylls, phytosterols and pre-ß1-HDL differed markedly, suggesting differences in intestinal lipidation of HDL. In addition, the in vitro investigations suggest an important role of plasma apoA-II in xanthophyll metabolism.

Co-deposition of salmeterol and fluticasone propionate by a combination inhaler.

The combination of the long-acting beta2-agonist, salmeterol xinafoate (salmeterol) and inhaled corticosteroid, fluticasone propionate (FP) (Seretide/Advair) has shown enhanced efficacy compared with concurrent administration of the two drugs from individual inhalers at the same dose. A possible explanation for this increased effect is a higher degree of co-deposition of the two drugs from the combination (Seretide) inhaler compared with the component drugs administered separately. Raman laser spectroscopy, a technique capable of identifying individual drug particles, has been used with novel statistical methodology that we have developed, to determine whether there is any co-association between drug particles and whether this occurs in the Seretide formulation rather than by chance. Samples from a combined Seretide metered dose inhaler (MDI, 25/50 mcg) and salmeterol (25 mcg) with FP (50 mcg) from separate MDI's taken from Plate 4 of an Anderson Cascade Impactor were analysed. Using a statistical test based on the bootstrap technique, it was found that the co-deposition of FP and salmeterol particles from the combination MDI was significantly greater than from the separate inhalers group (p < 0.001). A higher degree of co-deposition on the same cells of the airways may possibly account for the increased efficacy observed in patients prescribed Seretide MDI.