A population pharmacokinetics model of balovaptan to support dose selection in adult and pediatric populations.

Balovaptan is a brain-penetrating vasopressin receptor 1a antagonist previously investigated for the core symptoms of autism spectrum disorder (ASD). A population pharmacokinetic (PK) model of balovaptan was developed, initially to assist clinical dosing for adult and pediatric ASD studies and subsequently for new clinical indications including malignant cerebral edema (MCE) and post-traumatic stress disorder. The final model incorporates one-compartment disposition and describes time- and dose-dependent non-linear PK through empirical drug binding and a gut extraction component with turnover. An age effect on clearance observed in children was modeled by an asymptotic function that predicts adult-equivalent exposures at 40% of the adult dose for children aged 2-4 years, 70% for 5-9 years, and at the full adult dose for ≥ 10 years. The model was adapted for intravenous (IV) balovaptan dosing and combined with in vitro and ex vivo pharmacodynamic data to simulate brain receptor occupancy as a guide for dosing in a phase II trial of MCE prophylaxis after acute ischemic stroke. A sequence of three stepped-dose daily infusions of 50, 25 and 15 mg over 30 or 60 min was predicted to achieve a target occupancy of ≥ 80% in ≥ 95% of patients over a 3-day period. This model predicts both oral and IV balovaptan exposure across a wide age range and will be a valuable tool to analyze and predict its PK in new indications and target populations, including pediatric patients.

Lorcaserin for Dravet Syndrome: A Potential Advance Over Fenfluramine?

Lorcaserin, a selective serotonin 5-HT2C receptor agonist, was developed as an appetite suppressant with the rationale of minimizing the risk of cardiovascular toxicity associated with non-selective serotoninergic agents such as fenfluramine. Eight years after FDA approval, however, it was withdrawn from the market, when a large safety study suggested a potential cancer risk. Following in the fenfluramine footsteps and utilizing the repurposing approach coupled with the regulatory orphan drug designation, lorcaserin is currently in clinical development for the treatment of epilepsy. This potential novel indication builds on the evidence that 5-HT2C receptor stimulation can protect against seizures, and accounts at least in part for fenfluramine's antiseizure effects in Dravet syndrome models. In animal models, lorcaserin shows a narrower range of antiseizure activity than fenfluramine. In particular, lorcaserin is inactive in classical acute seizure tests such as maximal electroshock and subcutaneous pentylenetetrazole in mice and rats, and the 6-Hz stimulation model in mice. However, it is active in the GAERS absence seizure model, and in mutant zebrafish models of Dravet syndrome. Preliminary uncontrolled studies in patients with Dravet syndrome have yielded promising results, and a phase III, double-blind, placebo-controlled, parallel group trial is currently ongoing to assess its efficacy and safety in children and adults with Dravet syndrome.

Phase 1 study of 2 high dose intensity schedules of the pan-Notch inhibitor crenigacestat (LY3039478) in combination with prednisone in patients with advanced or metastatic cancer.

Background Crenigacestat is a potent Notch inhibitor that decreases Notch signaling and its downstream biological effects. Here, we report the results from Part F of study 16F-MC-JJCA designed to evaluate the safety, pharmacokinetics (PK), and antitumor activity of crenigacestat with prednisone in advanced or metastatic cancer. The combination was planned to mitigate gastrointestinal toxicities. Methods Eligible patients (Study Part F) received crenigacestat loading dose (75 mg, escalating to 150 mg) administered thrice weekly (TIW) (F1) or twice weekly (BIW) (F2) for 2 weeks during Cycle 1, followed by 50 mg TIW from week 3 onwards. Prednisone was co-administered for 2 weeks in Cycle 1. Results Twenty-eight patients were enrolled; 11 in F1 (median age, 63 years), 17 in F2 (median age, 50 years). Dose-limiting toxicities were Grade 3 increased serum amylase and Grade 2 fatigue in F1, and Grade 4 hypophosphatemia and Grade 3 rash maculo-papular in F2. The maximum tolerated dose was 75 mg in F1 and 100 mg in F2. Best overall response was stable disease (F1, 6 [54.5%] patients; F2, 11 [64.7%] patients). Pharmacokinetic was dose proportional. Prednisone did not modify PK of crenigacestat, and both F1 and F2 achieved pharmacodynamics effects on evaluable tumor tissue samples. Conclusions This study demonstrated the potential use of prednisone to reduce gastrointestinal (GI) toxicities of a Notch inhibitor without affecting its PK. The safety profile observed was consistent with Notch pathway inhibitors, and the maximum tolerated dose was 75 mg TIW and 100 mg BIW in F1 and F2, respectively. ClinicalTrials.gov: NCT01695005.

A Phase II and Pharmacodynamic Trial of RO4929097 for Patients With Recurrent/Progressive Glioblastoma.

BACKGROUND: Cancer stem-like cells are a major cause of resistance to therapy in patients with glioblastoma (GBM) as well as other cancers. Tumor cells are maintained in a stem-like proliferative state in large part through the Notch signaling pathway. The function of this pathway in turn depends on gamma secretase activity. Inhibition of this enzyme therefore inhibits the Notch pathway and tumor growth as measured by a reduction in the formation of brain tumor neurospheres in murine models. RO4929097 is an oral gamma secretase inhibitor. OBJECTIVE: To estimate the 6-mo progression-free survival rate (PFS6) in patients with progressive GBM and to inhibit by 50% the generation of neurospheres in fresh tissue resected from patients treated with RO4929097. METHODS: In this phase II and pharmacodynamic study, patients with recurrent GBM received RO4929097 in a study of 2 groups. Group A patients had unresectable disease and received drug in a standard phase II design. Group B patients had resectable disease and received drug before and after surgical resection. Endpoints included PFS6 and the inhibition of neurosphere formation in the resected tumor samples. RESULTS: A total of 47 patients received treatment, 7 of whom had tumor resection. The PFS6 was 4%, and the inhibition of neurosphere formation occurred in 1 of 7 patient samples. CONCLUSION: RO4929097 was inactive in recurrent GBM patients and demonstrated minimal inhibition of neurosphere formation in fresh tissue samples.

Phase 1 study to evaluate Crenigacestat (LY3039478) in combination with dexamethasone in patients with T-cell acute lymphoblastic leukemia and lymphoma.

BACKGROUND: Deregulated Notch signaling is implicated in T-cell acute lymphoblastic leukemia (T-ALL)/T-cell lymphoblastic lymphoma (T-LBL). Crenigacestat (LY3039478) prevents cleavage of Notch proteins and may benefit patients with relapsed/refractory T-ALL/T-LBL. METHODS: JJCB was a multicenter, nonrandomized, open-label, dose-escalation, phase 1 study in adult patients with relapsed/refractory T-ALL/T-LBL. Eligible patients received Crenigacestat orally 3 times per week plus dexamethasone at 24 mg twice daily on days 1 to 5 every other week in a 28-day cycle. The starting level of Crenigacestat was 50 mg, and dose escalation was performed with a modified 3+3 scheme for the estimation of dose-limiting toxicity (DLT) at the recommended dose level. RESULTS: In total, 36 patients with T-ALL (n = 31 [86.1%]) or T-LBL (n = 5 [13.9%]) were treated with Crenigacestat and dexamethasone. Six patients (16.7%) experienced DLTs: 2 of 12 (16.7%) in the 75-mg cohort (grade 4 gastrointestinal hemorrhage and grade 3 nausea, vomiting, and diarrhea), 1 of 15 (6.7%) in the 100-mg cohort (grade 3 diarrhea), and 3 of 3 (100%) in the 125-mg cohort (grade 3 diarrhea, nausea, and vomiting). The maximum tolerated dosewas 75 mg plus 24 mg of dexamethasone daily on days 1 to 5. Twenty-eight patients (77.8%) experienced 1 or more treatment-emergent adverse events related to the study treatment. The best overall response was a confirmed response, with 1 patient (2.8%) having a duration of response of 10.51 months. Six patients (16.7%) achieved stable disease, and 12 patients (33.3%) experienced progressive disease. The remaining 17 patients (47.2%) were not evaluable. The median event-free survival was 1.18 months (95% confidence interval, 0.76-2.14 months) among all groups. A pharmacodynamic analysis showed decreased plasma amyloid ß levels. CONCLUSIONS: Crenigacestat demonstrated limited clinical activity at the recommended dose in adult patients with relapsed/refractory T-ALL/T-LBL.

A phase I study of an oral selective gamma secretase (GS) inhibitor RO4929097 in combination with neoadjuvant paclitaxel and carboplatin in triple negative breast cancer.

Upregulation of Notch pathway is associated with poor prognosis in breast cancer. We present the results of a phase I study of an oral selective gamma secretase (GS) inhibitor (critical to Notch signaling), RO4929097 in combination with neoadjuvant chemotherapy for operable triple negative breast cancer. The primary objective was to determine the maximum tolerated dose (MTD) of RO4929097. Secondary objectives were to determine real-time pharmacokinetics of RO4929097 and paclitaxel, safety and pathologic (pCR) complete response to study treatment. Eligible patients, initiated carboplatin at AUC 6 administered intravenously (IV) on day 1, weekly paclitaxel at 80 mg/m2 IV and RO4929097 10 mg daily given orally (PO) on days 1-3, 8-10 and 15-17 for six 21-day cycles. RO4929097 was escalated in 10 mg increments using the 3 + 3 dose escalation design. Two DLTs were observed in 14 patients - Grade (G) 4 thrombocytopenia in dose level 1 (10 mg) and G3 hypertension in dose level 2 (20 mg). Protocol-defined MTD was not determined due to discontinuation of RO4929097 development. However, 4 of 5 patients enrolled to 20 mg dose of RO4929097 required dose reduction to 10 mg due to toxicities (including neutropenia, thrombocytopenia and hypertension) occurring during and beyond the DLT observation period. Thus, 10 mg would have been the likely dose level for further development. G3 or higher hematologic toxicities included neutropenia (N = 8, 57%) and thrombocytopenia (N = 5, 36%) patients. Six (43%) patients had G2-3 neuropathy requiring paclitaxel dose reduction. No signs of drug-drug interaction between paclitaxel and RO4929097 were evident. Five patients (36%) had pCR.

Safety and clinical activity of the Notch inhibitor, crenigacestat (LY3039478), in an open-label phase I trial expansion cohort of advanced or metastatic adenoid cystic carcinoma.

Background Deregulated Notch signaling is implicated in multiple cancers. The phase I trial (I6F-MC-JJCA) investigated the safety and anti-tumor activity of crenigacestat (LY3039478), a selective oral Notch inhibitor, in an expansion cohort of patients with adenoid cystic carcinoma (ACC) who received the dose-escalation-recommended phase 2 dose (RP2D), established previously (Massard C, et al., Annals Oncol 2018, 29:1911-17). Methods Patients with advanced or metastatic cancer, measurable disease, ECOG-PS ≤1, and baseline tumor tissue were enrolled. Primary objectives were to identify a safe RP2D, confirm this dose in expansion cohorts, and document anti-tumor activity. Secondary objectives included safety and progression-free survival (PFS). The ACC expansion cohort received the RP2D regimen of 50 mg crenigacestat thrice per week in a 28-day cycle until disease progression or other discontinuation criteria were met. Results Twenty-two patients with ACC were enrolled in the expansion cohort (median age of 60 years). Median treatment duration was 3 cycles with 6 patients remaining on treatment. There were no objective responses; 1 (5%) patient had an unconfirmed partial response. Disease control rate was 73% and 4 patients had stable disease ≥6 months. Median PFS was 5.3 months (95%CI: 2.4-NE)) for the 22 patients; and 7.7 months (95%CI: 4.0-NR) and 2.4 months (95%CI: 1.1-NE) in the subgroup of patients in second-line (n = 7) or ≥ third-line (n = 9), respectively. Frequent treatment-related-adverse events (all grades) included diarrhea, fatigue, vomiting, decreased appetite, dry mouth, and dry skin. There were no new safety signals. Conclusion The crenigacestat RP2D regimen induced manageable toxicity and limited clinical activity, without confirmed responses, in heavily pretreated patients with ACC.

Lorcaserin: A review of its preclinical and clinical pharmacology and therapeutic potential.

The selective 5-HT2C receptor agonist lorcaserin, in conjunction with lifestyle modification, was approved by the FDA in 2012 for weight management. It has been marketed in the US as Belviq® since 2013. This article provides a review of the preclinical and clinical pharmacology of lorcaserin, including its pharmacokinetic and safety profiles. Preclinical studies with lorcaserin initially focused on simple measures of food intake and body weight gain, but have now expanded to include studies on its effects on appetitive aspects of feeding behaviour and models of binge-eating. A significant number of studies have also shown that lorcaserin alters behaviours related to drug use and addiction, in rodents and non-human primates. Potential clinically-relevant effects of lorcaserin have also been reported in models of pain and seizure-like activity. Not surprisingly, the majority of clinical work with lorcaserin has focused on its effects on weight gain, and on physiological processes related to energy intake. However, results of clinical trials and experimental laboratory studies involving lorcaserin are now appearing which describe effects on a range of other behaviours and physiological functions. These include smoking cessation, cocaine self-administration, and behavioural and brain responses to food cues. All of this work suggests that lorcaserin may have therapeutic potential for a variety of disorders and conditions beyond obesity. Based on clinical experience, including the outcomes from several, large, well-powered clinical obesity trials at the approved 10mg BID dose both pre and post approval, a priori concerns about cardiac valvulopathy have largely been allayed. However, as with any recently approved first-in-class pharmacotherapy, there may be yet-unknown risks, as well as benefits, associated with use of lorcaserin. Nonetheless, the current safety profile and an expanding post approval safety data base should encourage further experimental laboratory-based and clinical trial-based research with lorcaserin in targeted populations to investigate its full therapeutic potential.

Discovery of Ziresovir as a Potent, Selective, and Orally Bioavailable Respiratory Syncytial Virus Fusion Protein Inhibitor.

Ziresovir (RO-0529, AK0529) is reported here for the first time as a promising respiratory syncytial virus (RSV) fusion (F) protein inhibitor that currently is in phase 2 clinical trials. This article describes the process of RO-0529 as a potent, selective, and orally bioavailable RSV F protein inhibitor and highlights the in vitro and in vivo anti-RSV activities and pharmacokinetics in animal species. RO-0529 demonstrates single-digit nM EC50 potency against laboratory strains, as well as clinical isolates of RSV in cellular assays, and more than one log viral load reduction in BALB/c mouse model of RSV viral infection. RO-0529 was proven to be a specific RSV F protein inhibitor by identification of drug resistant mutations of D486N, D489V, and D489Y in RSV F protein and the inhibition of RSV F protein-induced cell-cell fusion in cellular assays.

Discovery of a potent tyrosine kinase AXL inhibitor bearing the 3-((2,3,4,5-tetrahydro-1H-benzo[d]azepin-7-yl)amino)pyrazine core.

Starting from the recently launched FLT3/AXL multi-targeted inhibitor Gilteritinib (5), we conducted a side-chain ring closure medicinal chemistry approach leading to the identification of compound 15c as a highly potent AXL inhibitor in the biochemical and cellular anti-proliferative assays, with IC50 values of 1.2 and 0.3 nM, respectively. Compared with the reference compound 5, our new discovered AXL inhibitor 15c is more potent in both assays.

UPLC/MS-MS assay development for estimation of mozavaptan in plasma and its pharmacokinetic study in rats.

AIM: Mozavaptan is a nonpeptide vasopressin receptor antagonist approved for the treatment of ectopic antidiuretic hormone secretion syndrome. METHODS & RESULTS: A simple, rapid and fully validated UPLC/MS-MS method was developed for the quantitation of mozavaptan in rat plasma. The chromatographic separation was conducted on an Acquity UPLC BEH™ C18 column with an optimum mobile phase of 10 mM ammonium acetate buffer and 0.1% formic acid in acetonitrile (30:70 v/v) at a flow rate of 0.3 ml/min. The multiple reaction monitoring transitions were performed at m/z 428.16→119.03 for mozavaptan and m/z 237.06→179.10 for carbamazepine (internal standard). CONCLUSION: The method was effectively applied for the determination of mozavaptan pharmacokinetic parameters after the oral administration of 3 mg/kg mozavaptan in rats.

Effects of a Fixed-Dose Co-Formulation of Daclatasvir, Asunaprevir, and Beclabuvir on the Pharmacokinetics of a Cocktail of Cytochrome P450 and Drug Transporter Substrates in Healthy Subjects.

BACKGROUND: A fixed-dose combination of daclatasvir (DCV; hepatitis C virus NS5A inhibitor), asunaprevir (ASV; non-structural protein 3 inhibitor), and beclabuvir (BCV; non-structural protein 5B inhibitor) is approved in Japan for hepatitis C virus genotype 1. OBJECTIVE: The objective of this study was to assess the combination's drug-drug interaction potential in vivo using a validated cocktail of eight cytochrome P450 (CYP) and transporter probes. METHODS: We conducted an open-label single-sequence study in healthy adults (n = 20) given single-dose caffeine (CYP1A2 substrate), metoprolol (CYP2D6), flurbiprofen (CYP2C9), montelukast (CYP2C8), omeprazole (CYP2C19), midazolam (CYP3A4), digoxin (P-glycoprotein), and pravastatin (organic anion-transporting polypeptide), alone or with steady-state twice-daily DCV/ASV/BCV 30/200/75 mg (with or without additional BCV 75 mg to adjust for higher exposure in hepatitis C virus infection). RESULTS: Daclatasvir/asunaprevir/beclabuvir did not affect CYP1A2, CYP2C8, or CYP2C9; the probe maximum observed concentration and area under the concentration-time curve extrapolated to infinite time geometric mean ratios and 90% confidence intervals were all within the 0.8-1.25 bioequivalence range. Beclabuvir showed moderate dose-dependent CYP2C19 induction; omeprazole maximum observed concentration and area under the concentration-time curve from 0 to the last quantifiable concentration were lower with additional BCV [geometric mean ratio 0.36 (90% confidence interval 0.23-0.55) and 0.34 (0.25-0.46), respectively] than without [0.57 (0.42-0.78), 0.48 (0.39-0.59)]. Weak-to-moderate CYP3A4 induction was observed, plus weak CYP2D6, P-glycoprotein, and organic anion-transporting polypeptide inhibition [maximum observed concentration and area under the concentration-time curve extrapolated to infinite time without additional BCV: midazolam 0.57 (0.50-0.65), 0.53 (0.47-0.60); metoprolol 1.40 (1.20-1.64), 1.71 (1.49-1.97); digoxin 1.23 (1.12-1.35), 1.23 (1.17-1.29); pravastatin 2.01 (1.63-2.47), 1.68 (1.43-1.97)]. CONCLUSIONS: No dose adjustments with DCV/ASV/BCV are indicated for CYP1A2, CYP2C8, CYP2C9, or P-glycoprotein substrates. CYP3A4, CYP2D6, and OATP substrates should be co-administered with caution. Co-administration with agents solely metabolized by CYP2C19 is not recommended.

Low-dose tolvaptan PK/PD: comparison of patients with hyponatremia due to syndrome of inappropriate antidiuretic hormone secretion to healthy adults.

PURPOSE: Tolvaptan (TLV) is indicated to treat hyponatremia due to syndrome of inappropriate diuretic hormone (SIADH) in Europe. Treatment is to be initiated at 15 mg QD but post-approval reporting indicates increasing use of 7.5 mg as the starting dose. Physicians believe 7.5 mg is effective and has a lower incidence of overly rapid correction of serum sodium. METHODS: Single TLV doses of 3.75, 7.5, and 15 mg were administered to 14 healthy adults in a crossover design and to 29 subjects ≥18 years with SIADH and serum sodium between 120 and 133 mmol/L in a parallel-group design. Pharmacodynamics and TLV plasma concentrations were assessed for 24 h post-dose. RESULTS: In SIADH subjects, corrections of serum sodium (Δ of ≥8 mmol/L in the first 8 h or ≥12 mmol/L in the first 24 h) were observed in one, one, and two subjects in the 3.75-, 7.5-, and 15-mg dose groups. Fluid balance (FB) for 0-6 h post-dose was correlated (r 2 = 0.37) with maximum increases in serum sodium; subjects with large corrections had large (~1 L) negative FB. Compared to healthy adults, subjects with SIADH did not drink in response to their negative FB and had larger increases in serum sodium at 24 h. Median time of maximum increase in healthy adults was 6 h, with no rapid corrections, and FB was near 0 mL by 24 h. CONCLUSION: Starting titration with 7.5 mg TLV will not eliminate the risk of rapid corrections in serum sodium. Monitoring FB may indicate that a subject is at risk for over correction.

Integrative Development of a TLR8 Agonist for Ovarian Cancer Chemoimmunotherapy.

Purpose: Immunotherapy is an emerging paradigm for the treatment of cancer, but the potential efficacy of many drugs cannot be sufficiently tested in the mouse. We sought to develop a rational combination of motolimod-a novel Toll-like receptor 8 (TLR8) agonist that stimulates robust innate immune responses in humans but diminished responses in mice-with pegylated liposomal doxorubicin (PLD), a chemotherapeutic that induces immunogenic cell death.Experimental Design: We followed an integrative pharmacologic approach including healthy human volunteers, non-human primates, NSG-HIS ("humanized immune system") mice reconstituted with human CD34+ cells, and patients with cancer to test the effects of motolimod and to assess the combination of motolimod with PLD for the treatment of ovarian cancer.Results: The pharmacodynamic effects of motolimod monotherapy in NSG-HIS mice closely mimicked those in non-human primates and healthy human subjects, whereas the effects of the motolimod/PLD combination in tumor-bearing NSG-HIS mice closely mimicked those in patients with ovarian cancer treated in a phase Ib trial (NCT01294293). The NSG-HIS mouse helped elucidate the mechanism of action of the combination and revealed a positive interaction between the two drugs in vivo The combination produced no dose-limiting toxicities in patients with ovarian cancer. Two subjects (15%) had complete responses and 7 subjects (53%) had disease stabilization. A phase II study was consequently initiated.Conclusions: These results are the first to demonstrate the value of pharmacologic approaches integrating the NSG-HIS mouse, non-human primates, and patients with cancer for the development of novel immunomodulatory anticancer agents with human specificity. Clin Cancer Res; 23(8); 1955-66. ©2016 AACR.

Synthesis and evaluation of novel 2,4-diaminopyrimidines bearing bicyclic aminobenzazepines for anaplastic lymphoma kinase (ALK) inhibitor.

A series of novel 2,4-diaminopyrimidine compounds bearing bicyclic aminobenzazepine were synthesized and evaluated for their anti-ALK activities. The activities of these compounds were confirmed in both enzyme- and cell-based ALK assays. Amongst compounds synthesized, KRCA-0445 showed very promising results in pharmacokinetic study and in vivo efficacy study with H3122 xenograft mouse model.

Can serum albumin level affect the pharmacological action of tolvaptan in patients with liver cirrhosis? A post hoc analysis of previous clinical trials in Japan.

BACKGROUND: Patients with hypoalbuminemia often fail to respond to increased doses of loop diuretics. We therefore performed a post hoc analysis to investigate the pharmacological action of tolvaptan and whether it is dependent on the serum albumin level. METHODS: This analysis was based on four previous clinical trials of tolvaptan in patients with liver cirrhosis who exhibited insufficient response to conventional diuretics. We analyzed the correlation between the change in the initial 24-h cumulative urine volume from baseline and the serum albumin level at baseline, and assessed potential predictive factors of response to tolvaptan. RESULTS: The correlation coefficient was 0.029 in the placebo group and -0.112 in the 7.5 mg tolvaptan group of patients with liver cirrhosis. Administration of tolvaptan provoked a stable response regardless of the serum albumin level. Tolvaptan use was identified as a significant predictor of pharmacological action, and was shown to change the initial urine volume by 885 mL (P < 0.0001) in liver cirrhosis patients. CONCLUSIONS: In this post hoc analysis, tolvaptan increased the initial urine volume from baseline regardless of serum albumin levels. Use of tolvaptan as an add-on therapy to loop diuretics can be considered an optimal therapeutic option in patients with insufficient response to loop diuretics.

Pharmacokinetic-pharmacodynamic modeling of the effect of varenicline on nicotine craving in adult smokers.

INTRODUCTION: Varenicline has been shown to significantly reduce craving and several aspects of smoking reinforcement in clinical trials, compared with placebo. This is the first report describing the concentration-effect relationship of varenicline on relief of craving. METHODS: The pharmacokinetics (PK) and pharmacodynamics (PD) of a single 2mg dose of varenicline were investigated in 40 smokers in a randomized, crossover study comparing the effect of varenicline with placebo on ameliorating abstinence-and cue-induced craving and withdrawal symptoms. Subjects were asked to complete self-reported questionnaires (Smoking Urges Scale and Minnesota Nicotine Withdrawal Scale [MNWS]) and blood samples were simultaneously collected for measurement of varenicline concentrations. Only the data from the 4-hr postdose abstinence period (just prior to the cue session) were analyzed. Data were described by a 2-compartment PK model and a linear PD model with first-order onset/offset rate constants describing the placebo response "kinetics." Response was described as the net effect of the baseline, placebo, and drug responses. RESULTS: Varenicline significantly decreased mean craving score when compared with placebo and the magnitude of this response was related to varenicline concentration. The time-course and magnitude of both placebo and varenicline craving response were characterized by a large degree of unexplained variability. Simulations were used to illustrate the expected craving response over time and its associated random variability after chronic dosing. CONCLUSIONS: Craving reduction is associated with increased varenicline concentrations. The relatively rapid onset of this effect within 4 hr postdose suggests that, smokers may experience some craving relief after acute administration of varenicline.

A multicenter phase 1 study of γ -secretase inhibitor RO4929097 in combination with capecitabine in refractory solid tumors.

BACKGROUND: RO4929097 is an oral inhibitor of γ -secretase that results in Notch signaling inhibition. Prior work has demonstrated that Notch signaling inhibition enhances chemotherapy sensitivity of cancer cells. This phase I study was conducted to determine maximum tolerated dose (MTD), toxicities and efficacy of RO4929097 and capecitabine in advanced solid tumors. METHODS: Patients with refractory solid tumors received capecitabine at a fixed dose of 1,000 mg/m(2) twice daily with escalating doses of RO4929097 on a 21-day cycle in a 3 + 3 design. Capecitabine was administered for 14 days and the RO49029097 once daily, 3 days per week, both for a 21 day cycle. RESULTS: Thirty patients were treated on six dose levels (20 to 150 mg). The maximally tolerated dose was not reached. One dose limiting toxicity was observed at each level 3 through 6 (hypophosphatemia, fatigue, and nausea/vomiting). Three confirmed partial responses were observed: two patients with fluoropyrimide-refractory colon cancer and one patient with cervical cancer. Autoinduction of RO4929097 was demonstrated with increasing dose levels and duration. CONCLUSIONS: The recommended phase 2 dose is capecitabine 1,000 mg/m(2) orally twice daily on days 1 through 14 with RO4929097 20 mg orally once daily on days 1-3, 8-10 and 15-17 with a 21 day cycle. Clinical benefit was observed in cervical and colon cancer. Autoinduction of RO4929097 was seen both with increasing cycle number and increasing dose. Plasma concentrations of RO4929097 were above those needed for Notch inhibition.

Efficacy of tolvaptan added to furosemide in heart failure patients with advanced kidney dysfunction: a pharmacokinetic and pharmacodynamic study.

BACKGROUND AND OBJECTIVES: The pharmacokinetics and pharmacodynamics of tolvaptan (7.5 or 15 mg/day) in combination with furosemide have been investigated in heart failure (HF) patients with normal kidney function but not in HF patients with advanced kidney dysfunction. This study evaluated the efficacy of tolvaptan in HF patients with advanced kidney dysfunction (estimated glomerular filtration rate <45 mL/min/1.73 m(2)) by conducting a pharmacokinetic and pharmacodynamic study in these patients. METHODS: Tolvaptan (15 mg once daily) was administered orally for 7 days in combination with furosemide (40-200 mg). RESULTS: The peak plasma tolvaptan concentration and area under the plasma concentration-time curve were 379.41 ± 149.69 ng/mL and 4,657.38 ± 2,741.79 ng·h/mL, respectively, in HF patients with advanced kidney dysfunction. These values were greater in HF patients with advanced kidney dysfunction than values reported in the literature for healthy subjects and HF patients with normal kidney function. Urine volume increased and body weight decreased significantly compared with those before tolvaptan administration in HF patients with advanced kidney dysfunction. CONCLUSION: This study showed that adding tolvaptan to furosemide was effective in HF patients with advanced kidney dysfunction. This study also suggests that in these patients 15 mg/day of tolvaptan should be sufficient, and increasing the dose or the frequency of dosing to overcome diuretic resistance should not be necessary, and consideration should be given to using a lower dose and/or prolonging the dosing interval.

A phase I dose-finding study of the novel Toll-like receptor 8 agonist VTX-2337 in adult subjects with advanced solid tumors or lymphoma.

PURPOSE: This phase I, open-label, uncontrolled, ascending-dose study explored the safety, maximum tolerated dose (MTD), pharmacokinetics, and pharmacology of the TLR8 agonist VTX-2337 in subjects with advanced solid tumors or lymphoma. EXPERIMENTAL DESIGN: VTX-2337 doses (0.1-3.9 mg/m(2)) were administered subcutaneously on days 1, 8, and 15 of each 28-day cycle. Safety/tolerability assessments included adverse events (AE); physical, ophthalmologic, and laboratory evaluations; and electrocardiograms. Dose-limiting toxicities (DLT) were evaluated during the first cycle. Pharmacokinetics were evaluated after the first dose. Plasma samples were quantitatively assessed for chemokines, cytokines, and other inflammatory mediators. Antitumor activity was assessed. RESULTS: Thirty-three subjects were enrolled in 8 cohorts and received an average of 2 treatment cycles (range, 1-8 cycles). Most AEs were grades 1 to 2; the most common drug-related AEs were injection site reactions, chills, pyrexia, and influenza-like illness. One DLT was reported: grade 3 hypotension (3.9 mg/m(2)). The MTD was considered the highest dose administered. Peak drug plasma levels and total systemic exposure were generally dose proportional. At doses ≥0.4 mg/m(2), increases above baseline levels were observed for plasma levels of G-CSF, monocyte chemoattractant protein-1, macrophage inflammatory protein-1ß, and TNFα. Eight subjects (24.2%) had a best response of stable disease (median duration, 54.5 days). CONCLUSIONS: VTX-2337 is clinically well tolerated and biologically active with a predictable pharmacokinetic profile. Suitable doses for testing in combination studies were identified. Phase II placebo-controlled studies of VTX-2337 in combination with doxorubicin in ovarian cancer, and in combination with platinum chemotherapy, 5 FU, and cetuximab in head and neck cancer have been initiated (NCT #01666444 and NCT#01836029).