GM-1020: a novel, orally bioavailable NMDA receptor antagonist with rapid and robust antidepressant-like effects at well-tolerated doses in rodents.

The NMDA receptor (NMDAR) antagonist ketamine has shown great potential as a rapid-acting antidepressant; however, its use is limited by poor oral bioavailability and a side effect profile that necessitates in-clinic dosing. GM-1020 is a novel NMDAR antagonist that was developed to address these limitations of ketamine as a treatment for depression. Here, we present the preclinical characterization of GM-1020 alongside ketamine, for comparison. In vitro, we profiled GM-1020 for binding to NMDAR and functional inhibition using patch-clamp electrophysiology. In vivo, GM-1020 was assessed for antidepressant-like efficacy using the Forced Swim Test (FST) and Chronic Mild Stress (CMS), while motor side effects were assessed in spontaneous locomotor activity and on the rotarod. The pharmacokinetic properties of GM-1020 were profiled across multiple preclinical species. Electroencephalography (EEG) was performed to determine indirect target engagement and provide a potentially translational biomarker. These results demonstrate that GM-1020 is an orally bioavailable NMDAR antagonist with antidepressant-like efficacy at exposures that do not produce unwanted motor effects.

Rapid tolerance to behavioral effects of ethanol in rats: Prevention by R-(-)-ketamine.

R-(-)-ketamine has emerged as a potentially improved medication over that of the (S)-isomer (marketed as Spravato for depression). Recent data have suggested (R)-ketamine could have value in the treatment of substance use disorder. The present set of experiments was undertaken to examine whether (R)-ketamine might prevent tolerance development. Rapid ethanol (ETOH) tolerance was studied since racemic ketamine had previously been shown to block this tolerance development in rats. In the present study, male Sprague-Dawley rats were given two large doses of ETOH on Day 1 (2.3 + 1.7 g/kg) and 2.3 g/kg ETOH on Day 2. Animals were tested for effects of 2.3 g/kg ETOH on grip strength, inclined screen performance and rotarod performance on Day 1 with or without (R)-ketamine as a pretreatment. (R)-ketamine alone was tested at the highest dose studied (10 mg/kg) and did not significantly influence any dependent measure. (R)-ketamine (1-10 mg/kg) did not alter the acute effects of ETOH except for enhancing the effects of ETOH on the inclined screen test at 3 mg/kg. Between-subjects analysis documented that tolerance developed to the effects of ETOH only on the measure of grip strength. (R)-ketamine (3 mg/kg) given prior to ETOH on Day 1 exhibited a strong trend toward preventing tolerance development (p = 0.062). The present results extend prior findings on the potential value of (R)-ketamine in substance abuse disorder therapeutics and add to the literature on NMDA receptor blockade as a tolerance-regulating mechanism.

A phase 1b expansion study of TAS-102 with oxaliplatin for refractory metastatic colorectal cancer.

BACKGROUND: TAS-102, a novel antimetabolite, is approved for treatment of refractory metastatic colorectal cancer (CRC). This study sought to determine whether the addition of TAS-102 to oxaliplatin (TAS-OX) was safe and effective in metastatic CRC previously treated with oxaliplatin. METHODS: This investigator-initiated, open-label, single-arm phase 1b study enrolled patients with metastatic CRC previously treated with 5-fluorouracil, irinotecan, and oxaliplatin. In dose escalation, TAS-102 was given at 3 dose levels: 25, 30, and 35 mg/m2 twice daily on day 1 to day 5 with 85 mg/m2 oxaliplatin on day 1 in 14-day cycles. The primary endpoint of dose escalation was the recommended dose for expansion, and in dose expansion, the primary endpoint was overall response rate (ORR) according to the Response Evaluation Criteria in Solid Tumors (RECIST, version 1.1). RESULTS: Forty-one patients were treated with TAS-OX. No dose-limiting toxicities were observed in the 11 patients treated in escalation. The recommended dose for expansion was 35 mg/m2 TAS-102 twice daily on day 1 to day 5 in combination with 85 mg/m2 oxaliplatin on day 1 in 14-day cycles. In the intention-to-treat population, the ORR was 2.4% (95% CI, 0%-12.9%) with 1 of 41 patients having a partial response, although 12 (29%) had tumor shrinkage. The median progression-free survival was 2.7 months (95% CI, 2.4-4.8 months) and median overall survival was 6.8 months (95% CI, 5.7-10 months). CONCLUSIONS: TAS-OX is safe with no unexpected toxicities at standard doses of each agent. The combination did not result in a clinically meaningful ORR, although progression-free survival and overall survival were encouraging in this heavily pretreated population. LAY SUMMARY: For metastatic colorectal cancer, the treatment combination of TAS-102 and oxaliplatin was found to be well-tolerated and revealed no unexpected side effects. Twelve of 41 patients had reductions in the size of their tumor, and the study treatment delayed the time to tumor growth as opposed to what would be expected.

Serious adverse events in African-American cancer patients with sickle cell trait and inherited haemoglobinopathies in a SEER-Medicare claims cohort.

African-American (AA) cancer patients have long-experienced worse outcomes compared to non-Hispanic whites (NHW). No studies to date have evaluated the prognostic impact of sickle cell trait (SCT) and other inherited haemoglobinopathies, of which several are disproportionately high in the AA population. In a cohort analysis of treated patients diagnosed with breast or prostate cancer in the linked SEER-Medicare database, the relative risk (RR) for ≥1 serious adverse events (AEs), defined as hospitalisations or emergency department visits, was estimated for 371 AA patients with a haemoglobinopathy (AA+) compared to patients without haemoglobinopathies (17,303 AA-; 144,863 NHW-). AA+ patients had significantly increased risk for ≥1 AEs compared to AA- (RR = 1.19; 95% CI 1.11-1.27) and NHW- (RR = 1.23; 95% CI 1.15-1.31) patients. The magnitude of effect was similar by cancer type, and in analyses of AA+ with SCT only. Our findings suggest a novel hypothesis for disparities in cancer outcomes.

Diagnostic Accuracy of MRI in Predicting Breast Tumor Size: Comparative Analysis of MRI vs Histopathological Assessed Breast Tumor Size.

BACKGROUND: Diagnostic accuracy of MRI in predicting breast tumor size: comparative analysis of breast tumor size byMRI vs histopathological assessment. PURPOSE: Tumor size is one of the most important factors in making a clinical and pathological assessment of breast cancer. The purpose of this study is to evaluate if MRI imaging is helpful for the surgeon in the preoperative accurate assessment of tumor size. METHODS: We retrospectively reviewed the charts of 124 patients who were diagnosed or managed at the Saint Francis /Mt. Sinai Regional Cancer Center. We then compared the preoperative MRI tumor size with the histopathological tumor size obtained at surgical resection. Tumors were divided into four histological groups: invasive ductal carcinoma (IDC), invasive lobular carcinoma (ILC), ductal carcinomain situ (DCIS), and mixed tumors (including mucinous, papillary, tubular, and apocrine breast carcinoma). MRI measurement of tumor size was compared against the reference size obtained from the microscopic measurement of the largest diameter of tumors. Concordance was defined as a difference ≤ 0.5 cm between MRI and pathology. RESULTS: A total of 124 patients with 147 breast tumors were included in our study. The mean age was 59.8 ± 12.72 years. Histologically, there were 81 IDC (55.10%), 35 DCIS (23.81%), 15 ILC (10.20%), and 16 mixed tumors (10.88%). Out of 147 tumors, 55.78% showed concordance of MRI and pathologic tumor size within 0.5 cm. MRI overestimated 31.97% and underestimated 12.24% of tumors. CONCLUSION: Breast MRI provides an additional tool for preoperative assessment of tumor size. In our study, we noted 56% concordance between MRI with pathological tumor size within 0.5 cm. Several factors, including grading of tumor, cancer type, and size, strongly affect the accuracy of MRI in the preoperative assessment of tumor size. High-grade tumor and DCIS are the two strongest negative factors resulting in overestimation of tumor size on MRI.

Effects of desvenlafaxine on blood pressure in patients treated for major depressive disorder: a pooled analysis.

OBJECTIVE: To evaluate the effect of the serotonin-norepinephrine re-uptake inhibitor desvenlafaxine on blood pressure and incidence of new onset hypertension in pooled short-term studies and in two longer-term, randomized withdrawal studies. RESEARCH DESIGN AND METHODS: Data from patients randomly assigned to desvenlafaxine 10 mg to 400 mg/day or placebo in 11 short-term (8-12 weeks), fixed-dose, double-blind, placebo-controlled studies of major depressive disorder (MDD) were pooled for analysis; two desvenlafaxine randomized withdrawal studies (36 and 46 weeks) were analyzed separately. CLINICAL TRIAL REGISTRATION: www.clinicaltrials.gov , NCT00072774, NCT00073762, NCT00277823, NCT00300378, NCT00384033, NCT00798707, NCT00863798, NCT01121484, NCT00824291, NCT01432457, NCT00075257, NCT00887224. MAIN OUTCOME MEASURES: Outcomes included change from baseline in supine systolic blood pressure (SSBP) and supine diastolic blood pressure (SDBP), assessed using a mixed model repeated measures (MMRM) analysis, and incidence of hypertension (defined as three consecutive second SDBP measures ≥90 mm Hg AND increase of ≥10 mm Hg from baseline and/or SSBP ≥140 mm Hg AND increase of ≥10 mm Hg), analyzed using Cochran Mantel Hanzael tests. Potential predictors of change in SSBP and SDBP at LOCF were examined by including predictor variables in a regression model. RESULTS: In the pooled, short-term studies, mean changes from baseline over time in SSBP and SDBP were statistically significant compared with placebo for the desvenlafaxine doses of 10 mg/day or greater for SSBP (p ≤ 0.0004; MMRM) and 25 mg/day or greater for SDBP (p ≤ 0.0449; MMRM). The proportion of patients with new onset hypertension differed significantly from placebo for the 50, 200, and 400 mg/day doses (1.9%, 2.4%, 4.8%, respectively, vs 0.8%; all p ≤ 0.0244). Predictors of change in BP included baseline SDBP, baseline SSBP, dose, body mass index, gender, age, race, and history of hypertension. LIMITATIONS: Data were pooled from studies which differed somewhat in study design and patient demographics. None of the studies were originally designed to examine treatment effects on BP. Study entry criteria limit generalization of these results to medically stable patients with a primary diagnosis of MDD. CONCLUSIONS: Short-term desvenlafaxine treatment was associated with small but statistically significant increases in SSBP and SDBP.

Pregabalin for the treatment of postoperative pain: results from three controlled trials using different surgical models.

PURPOSE: To evaluate the efficacy and safety of pregabalin (150 or 300 mg/d) as an adjunctive therapy for the treatment of postoperative pain. PATIENTS AND METHODS: This study reports findings from three separate, multicenter, randomized, double-blind, placebo-controlled trials of adjunctive pregabalin for the treatment of postoperative pain. Patients underwent one of three categories of surgical procedures (one procedure per study): elective inguinal hernia repair (post-IHR); elective total knee arthroplasty (post-TKA); or total abdominal hysterectomy (posthysterectomy). The primary endpoint in each trial, mean worst pain over the past 24 hours, was assessed 24 hours post-IHR and posthysterectomy, and 48 hours post-TKA. Patients rated their pain on a scale from 0 to 10, with higher scores indicating greater pain severity. RESULTS: In total, 425 (post-IHR), 307 (post-TKA), and 501 (posthysterectomy) patients were randomized to treatment. There were no statistically significant differences between the pregabalin and placebo groups with respect to the primary endpoint in any of the three trials. The least squares mean difference in worst pain, between 300 mg/d pregabalin and placebo, was -0.7 (95% confidence interval [CI] =-1.4, -0.1; Hochberg adjusted P=0.067) post-IHR; -0.34 (95% CI =-1.07, 0.39; P=0.362) post-TKA; and -0.2 (95% CI =-0.66, 0.31; P=0.471) posthysterectomy. CONCLUSION: There were no significant differences between pregabalin and placebo with respect to the primary pain intensity measure in each of the three clinical trials. These studies encompass a large dataset (1,233 patients in total), and their results should be considered when assessing pregabalin's effectiveness in postoperative pain. Further studies are required to determine the potential pain-reducing benefit of pregabalin in the postoperative setting.

A randomized, double-blind, placebo-controlled trial and open-label extension study to evaluate the efficacy and safety of pregabalin in the treatment of neuropathic pain associated with human immunodeficiency virus neuropathy.

The objective of these studies was to assess the efficacy and safety of pregabalin in the treatment of human immunodeficiency virus (HIV)-associated neuropathic pain. Patients with HIV-associated distal sensory polyneuropathy (DSP) were randomized to treatment with flexible-dose pregabalin (150-600 mg/day) or placebo for 17 weeks in a single-blind, placebo lead-in, randomized, double-blind, parallel-group, placebo-controlled multinational trial. The primary efficacy outcome was the change in mean pain score on an 11-point numeric rating scale (NRS) from baseline to study endpoint. Participants who completed this trial were invited to participate in a 6-month open-label extension study with pregabalin. Of the 377 patients enrolled in the randomized controlled trial (pregabalin, n=183; placebo, n=194), 68.4% completed treatment. In the open-label extension, 217 patients were treated and 59.4% completed treatment. Both studies were terminated by the sponsor after a preplanned interim analysis indicated trial futility. At endpoint, the change from baseline in least-squares mean NRS pain scores in the intent-to-treat population was -2.04 for pregabalin versus -2.11 for placebo (P=.709). There were no significant differences between the pregabalin and placebo groups in the secondary efficacy measures. Incidence of adverse events was lower than seen in previous pregabalin studies. Overall, this trial did not show pregabalin to be more efficacious than placebo in treating HIV-associated DSP. Studies such as these, which fail to support their primary hypotheses, may be important in informing the methodology of future trials, especially when novel approaches to limit variability in the control group are included. ClinicalTrials.gov identifiers: NCT01049217 and NCT01145417.

A randomized trial of pregabalin in patients with neuropathic pain due to spinal cord injury.

OBJECTIVE: To assess the efficacy and tolerability of pregabalin for the treatment of central neuropathic pain after spinal cord injury (SCI). METHODS: Patients with chronic, below-level, neuropathic pain due to SCI were randomized to receive 150 to 600 mg/d pregabalin (n = 108) or matching placebo (n = 112) for 17 weeks. Pain was classified in relation to the neurologic level of injury, defined as the most caudal spinal cord segment with normal sensory and motor function, as above, at, or below level. The primary outcome measure was duration-adjusted average change in pain. Key secondary outcome measures included the change in mean pain score from baseline to end point, the percentage of patients with ≥30% reduction in mean pain score at end point, patient global impression of change scores at end point, and the change in mean pain-related sleep interference score from baseline to end point. Additional outcome measures included the medical outcomes study-sleep scale and the Hospital anxiety and depression scale. RESULTS: Pregabalin treatment resulted in statistically significant improvements over placebo for all primary and key secondary outcome measures. Significant pain improvement was evident as early as week 1 and was sustained throughout the treatment period. Adverse events were consistent with the known safety profile of pregabalin and were mostly mild to moderate in severity. Somnolence and dizziness were most frequently reported. CONCLUSIONS: This study demonstrates that pregabalin is effective and well tolerated in patients with neuropathic pain due to SCI. CLASSIFICATION OF EVIDENCE: This study provides class I evidence that pregabalin, 150 to 600 mg/d, is effective in reducing duration-adjusted average change in pain compared with baseline in patients with SCI over a 16-week period (p = 0.003, 95% confidence interval = -0.98, -0.20).

Sertraline treatment of children and adolescents with posttraumatic stress disorder: a double-blind, placebo-controlled trial.

OBJECTIVE: The aim of this study was to evaluate the safety and efficacy of sertraline in children and adolescents who met Diagnostic and Statistical Manual of Mental Disorders, 4th edition (DSM-IV) criteria for posttraumatic stress disorder (PTSD). METHOD: Children and adolescents (6-17 years old) meeting DSM-IV criteria for PTSD were randomized to 10 weeks of double-blind treatment with sertraline (50-200 mg/day) or placebo. The primary efficacy measure was the University of California, Los Angeles Post-Traumatic Stress Disorder Index for DSM-IV (UCLA PTSD-I). RESULTS: A total of 131 patients met entry criteria and were randomized to sertraline (n = 67; female, 59.7%; mean age, 10.8; mean UCLA PTSD-I score, 43.8 ± 8.5) or placebo (n = 62; female, 61.3%; mean age, 11.2; mean UCLA PTSD-I score, 42.1 ± 8.8). There was no difference between sertraline and placebo in least squares (LS) mean change in the UCLA PTSD-I score, either on a completer analysis (-20.4 ± 2.1 vs. -22.8 ± 2.1; p = 0.373) or on an last observation carried forward (LOCF) end point analysis (-17.7 ± 1.9 vs. -20.8 ± 2.1; p = 0.201). Attrition was higher on sertraline (29.9%) compared to placebo (17.7%). Discontinuation due to adverse events occurred in a 7.5% treated with sertraline and 3.2% treated with placebo. CONCLUSIONS: Sertraline was a generally safe treatment in children and adolescents with PTSD, but did not demonstrate efficacy when compared to placebo during 10 weeks of treatment. ClinicalTrials.gov Identifier: NCT00150306.

An open-label trial of riluzole in patients with treatment-resistant major depression.

OBJECTIVE: This study was conducted to determine the efficacy and safety of riluzole, a glutamate-modulating agent, in patients with recurrent major depression. METHOD: After a 1-week drug-free period, subjects 18 years or older with a diagnosis of recurrent major depression and a Montgomery-Asberg Depression Rating Scale score > or = 20 received riluzole monotherapy (100-200 mg/day) openly for 6 weeks. RESULTS: Nineteen treatment-resistant depressed patients, 53% of whom were classified as having stage 2 treatment resistance or greater, received riluzole at a mean dose of 169 mg/day. Significant improvement occurred during weeks 3 through 6 for all patients and weeks 2 through 6 for completers. CONCLUSIONS: Although preliminary, these results indicate that riluzole may have antidepressant properties in some patients.

Recognition of PSA-derived peptide antigens by T cells from prostate cancer patients without any prior stimulation.

Prostate-specific antigen (PSA) is a valuable marker antigen for prostate cancer. Lately considerable interest has been generated in the prospect of developing a vaccine for prostate cancer with PSA-derived peptide epitopes to induce cytotoxic T-cell (CTL) response. We report here that T cells capable of exhibiting PSA epitope-specific effector function-in their native state, i.e, without having to be further stimulated, in vitro-are detectable in more than half of the prostate cancer patients we studied. Ex vivo cultured autologous dendritic cells (DC) were used to present four HLA-A2-binding PSA peptide epitopes to freshly isolated peripheral blood lymphocytes (PBL) from patients and healthy volunteers. Ten out of 14 patients' PBL recognized at least one of the four peptides and 6 out of 10 patients' PBL recognized more than one peptide antigen as measured by IFN-gamma secretion upon stimulation of the PBL with the peptide antigen. Intracytoplasmic cytokine analysis for IFN-gamma in purified CD8(+) cells after stimulation with peptide antigens was tested in 6 patients and this technique demonstrated a similar response. Freshly isolated and purified CD8(+) cells when tested, also recognized the epitopes, as measured by IFN assay, when presented by transporter associated with antigen-processing (TAP) deficient T2 cells in an MHC-I restricted fashion. PBL from 9 normal donors when tested in identical fashion did not show any IFN-gamma production in recognition to the peptide antigens. Interestingly, neither of these CD8(+) T cells having IFN-gamma-producing ability did show any cytolytic activity in their native state against peptide loaded target cells or tumor cells when tested in cytotoxicity assay. In long term cocultures stimulation of purified CD8(+) T cells with matured DC pulsed with PSA peptides generated a PSA-specific CTL response in 4 of 6 patients studied and in 2 of 9 normal donors. While our observations of CTL generation are consistent with the prior reports that have demonstrated that specific CD8(+) CTL could be generated which recognize PSA-derived epitopes by in vitro stimulation by one means or another, this observation that IFN-gamma-producing CD8(+) T cells are present in patients which are antigen experienced, and do not require in vitro stimulation, is novel and has major implications for prostate cancer vaccine preparation.

Enhancing neuronal plasticity and cellular resilience to develop novel, improved therapeutics for difficult-to-treat depression.

There is growing evidence from neuroimaging and ostmortem studies that severe mood disorders, which have traditionally been conceptualized as neurochemical disorders, are associated with impairments of structural plasticity and cellular resilience. It is thus noteworthy that recent preclinical studies have shown that critical molecules in neurotrophic signaling cascades (most notably cyclic adenosine monophosphate [cAMP] response element binding protein, brain-derived neurotrophic factor, bcl-2, and mitogen activated protein [MAP] kinases) are long-term targets for antidepressant agents and antidepressant potentiating modalities. This suggests that effective treatments provide both trophic and neurochemical support, which serves to enhance and maintainnormal synaptic connectivity, thereby allowing the chemical signal to reinstate the optimal functioning of critical circuits necessary for normal affective functioning. For many refractory patients, drugs mimicking "traditional" strategies, which directly or indirectly alter monoaminergic levels, may be of limited benefit. Newer "plasticity enhancing" strategies that may have utility in the treatment of refractory depression include N-methyl-D-aspartate antagonists, alpha-amino-3-hydroxy-5-methylisoxazole propionate (AMPA) potentiators, cAMP phosphodiesterase inhibitors, and glucocorticoid receptor antagonists. Small-molecule agents that regulate the activity f growth factors, MAP kinases cascades, and the bcl-2 family of proteins are also promising future avenues. The development of novel, nonaminergic-based therapeutics holds much promise for improved treatment of severe, refractory mood disorders.

Monoamine and neuropeptide-related function: prospects for novel therapeutics of depression.

Treatment of depression has been dominated by monoamine hypotheses for nearly half a century. Although the ultimate downstream targets of manipulation of biogenic amine transport and metabolism are signal transduction cascades, neurotrophic factors and ultimately genomic fine-tuning, much of drug development has remained focused on strategies to facilitate a rapid initial augmentation of synaptic neurotransmitter levels. Both monoaminergic agents that are highly specific in their target receptor stimulation and agents that modify multiple monoamine systems will move through the stages of drug development in coming years. Furthermore, recent landmark successes and initial pilot data indicates that small molecule peptide receptor antagonists for substance P, corticotrophin releasing factor and eventually others will be of increasing importance, since they may more subtlety modulate neurotransmission and only act on already deranged neural circuits. Eventually treatment strategies may begin to target intracellular kinase and phosphatase activity and other signal systems responsible for transporter and receptor trafficking patterns, as well as via more direct pathways toward mobilization of neurotrophic factor activity. In the near future however, refinement of monoamine strategies to treat depression will continue to guide thinking and development of novel drugs for depression. This review focuses primarily on developments relevant for the evolution of monaminergic and neuropeptide-based drugs for depression.