Extended Evaluation of Virological, Immunological and Pharmacokinetic Endpoints of CELADEN: A Randomized, Placebo-Controlled Trial of Celgosivir in Dengue Fever Patients.

UNLABELLED: CELADEN was a randomized placebo-controlled trial of 50 patients with confirmed dengue fever to evaluate the efficacy and safety of celgosivir (A study registered at ClinicalTrials.gov, number NCT01619969). Celgosivir was given as a 400 mg loading dose and 200 mg bid (twice a day) over 5 days. Replication competent virus was measured by plaque assay and compared to reverse transcription quantitative PCR (qPCR) of viral RNA. Pharmacokinetics (PK) correlations with viremia, immunological profiling, next generation sequence (NGS) analysis and hematological data were evaluated as exploratory endpoints here to identify possible signals of pharmacological activity. Viremia by plaque assay strongly correlated with qPCR during the first four days. Immunological profiling demonstrated a qualitative shift in T helper cell profile during the course of infection. NGS analysis did not reveal any prominent signature that could be associated with drug treatment; however the phylogenetic spread of patients' isolates underlines the importance of strain variability that may potentially confound interpretation of dengue drug trials conducted during different outbreaks and in different countries. Celgosivir rapidly converted to castanospermine (Cast) with mean peak and trough concentrations of 5727 ng/mL (30.2 µM) and 430 ng/mL (2.3 µM), respectively and cleared with a half-life of 2.5 (± 0.6) hr. Mean viral log reduction between day 2 and 4 (VLR2-4) was significantly greater in secondary dengue than primary dengue (p = 0.002). VLR2-4 did not correlate with drug AUC but showed a trend of greater response with increasing Cmin. PK modeling identified dosing regimens predicted to achieve 2.4 to 4.5 times higher Cmin. than in the CELADEN trial for only 13% to 33% increase in overall dose. A small, non-statistical trend towards better outcome on platelet nadir and difference between maximum and minimum hematocrit was observed in celgosivir-treated patients with secondary dengue infection. Optimization of the dosing regimen and patient stratification may enhance the ability of a clinical trial to demonstrate celgosivir activity in treating dengue fever based on hematological endpoints. A new clinical trial with a revised dosing regimen is slated to start in 2016 (NCT02569827). Furthermore celgosivir's potential value for treatment of other flaviruses such as Zika virus should be investigated urgently. TRIAL REGISTRATION: ClinicalTrials.gov NCT01619969.

Efficacy and safety of celgosivir in patients with dengue fever (CELADEN): a phase 1b, randomised, double-blind, placebo-controlled, proof-of-concept trial.

BACKGROUND: Dengue infection is the most common mosquito-borne viral disease worldwide, but no suitable antiviral drugs are available. We tested the α-glucosidase inhibitor celgosivir as a treatment for acute dengue fever. METHODS: To establish eligibility for inclusion in a phase 1b, randomised, double-blind, placebo-controlled, proof-of-concept trial, individuals aged 21-65 years who had had a fever (≥38°C) for less than 48 h, met at least two criteria indicating probable dengue infection, and had a positive result on a dengue point-of-care test kit or PCR assay were referred for screening at a centre in Singapore between July 30, 2012, and March 4, 2013. Using a web-based system, we randomly assigned patients who met full inclusion criteria after screening (1:1; random permuted block length four) to celgosivir (initial 400 mg loading dose within 6 h of randomisation, followed by 200 mg every 12 h for a total of nine doses) or matched placebo. Patients and the entire study team were masked to group assignment. The primary endpoints were mean virological log reduction (VLR) from baseline for days 2, 3, and 4, and area under the fever curve (AUC) for a temperature above 37°C from 0 h to 96 h. Efficacy analyses were by intention to treat. This study is registered with ClinicalTrials.gov, number NCT01619969. FINDINGS: We screened 69 patients and randomly assigned 50 (24 to celgosivir, 26 to placebo). Mean VLR was greater in the celgosivir group (-1·86, SD 1·07) than in the placebo group (-1·64, 0·75), but the difference was non-significant (-0·22, 90% CI -0·65 to 0·22; one-sided p=0·203). The mean AUC was also higher in the celgosivir group (54·92, SD 31·04) than in the placebo group (40·72, 18·69), but again the difference was non-significant (14·20, 90% CI 2·16-26·25; one-sided p=0·973). We noted similar incidences of adverse events between groups. INTERPRETATION: Although generally safe and well tolerated, celgosivir does not seem to reduce viral load or fever burden in patients with dengue. FUNDING: STOP Dengue Translational Clinical Research.

Synthesis of indolizine derivatives with selective antibacterial activity against Mycobacterium tuberculosis.

1-substituted indolizines with activity against Mycobacterium tuberculosis have been synthesized. The most active compounds carry an hydroxyphenylmethyl- or hydroxyalkyl substituent in the indolizine 1-position. The alkyl chain should be moderately long (C-5 or C-6). Aryl groups in the 2- and 3-position of the indolizine are also required. Removal of the 3-substituent resulted in significant loss of activity. A nitrile substituent in the 7-position is beneficial for both chemical stability and bioactivity. The compounds studied display a narrow antibacterial spectrum and appear to be quite selective antimycobacterial compounds. Moderate activity against certain pathogenic protozoa was also observed.

Abrogation of skin disease in LUPUS-prone MRL/FASlpr mice by means of a novel tylophorine analog.

OBJECTIVE: To test the therapeutic effect of DCB-3503, a synthetic compound derived from a natural product that inhibits NF-kappaB, on end-organ disease in the MRL-Fas(lpr) murine model of systemic lupus erythematosus (SLE). METHODS: Eight-week-old female MRL/Fas(lpr) mice were treated intraperitoneally with a low (2 mg/kg) or high (6 mg/kg) dose of DCB-3503 for 10 weeks. Control groups were administered vehicle treatment alone (negative control) or 25 mg/kg cyclophosphamide (positive control). Mice were bled before (8 weeks) and during (13 weeks) treatment, and when they were killed (20 weeks), and serum samples were analyzed for total IgM and IgG levels and autoantibody titers. When the mice were killed, spleen and lymph nodes (axillary, brachial, and cervical) were examined by flow cytometric analysis. The presence of skin and renal disease was determined by histopathologic analysis. RESULTS: DCB-3503 reduced anti-double-stranded DNA and antichromatin autoantibodies and nearly abrogated inflammatory skin disease in MRL/Fas(lpr) mice; however, it had little effect on histologic kidney disease. Treated mice did not have hematologic or hepatic toxicity. These data indicate that end-organ disease in MRL/Fas(lpr) mice responds differentially to NF-kappaB inhibitor. CONCLUSION: DCB-3503 causes significant abrogation of skin disease in MRL/Fas(lpr) mice and may potentially be beneficial in the treatment of inflammatory skin disease in SLE.

Safety and efficacy of monotherapy with fantofarone, a novel calcium channel antagonist, in patients with chronic stable angina pectoris. Fantofarone Study Group.

Fantofarone is a calcium channel antagonist of a class (sulfone indolizine) that is structurally different from the existing classes. The primary cardiac action of fantofarone is on the sinus node, although it is also a potent peripheral and coronary vasodilator. This is a multicenter, double-blind, randomized, placebo-controlled, dose-ranging study evaluating the efficacy and safety of fantofarone. Three hundred and thirty patients were included as intent-to-treat, and 299 patients completed the entire protocol. Doses of fantofarone studied were 50, 100, 150, and 200 mg twice daily. The 100- and 150-mg groups demonstrated antianginal activity, prolonging exercise time walking on a treadmill by 38 and 45 seconds to the endpoint of moderate angina, compared with the placebo group. Sinus bradycardia occurred in 23 patients and was somewhat dose-related. Systolic blood pressure at rest and while exercising was not altered by therapy. No deaths occurred in the treated group. Of the 20 patients in the treatment group who did not complete the protocol (compared with 23 in the placebo group) 6 were dropped because of symptomatic bradycardia, 5 because of increased angina, and 9 for miscellaneous reasons. In doses of 100 mg to 150 mg twice daily, monotherapy fantofarone was effective and safe in the treatment of patients with chronic, stable angina pectoris.

BUCAST: another new antiviral.

AIDS: BUCAST is a butanoyl derivative of castanospermine, a naturally occurring plant alkaloid. BUCAST has been shown to make HIV less infectious and pathogenic by changing the sugar molecules of gp160. Test-tube experiments show BUCAST to have activity against both laboratory and clinical isolates of HIV and to be synergistic with AZT, ddC, and ddI. Maximum tolerated doses appear to be 400 mg per day, above which severe toxicities occur. BUCAST is rapidly absorbed when taken orally and is eliminated from the body in about 72 hours without appearing to accumulate. Several efficacy studies involving BUCAST are enrolling at sites in Kansas City, Fort Lauderdale, and San Francisco.^ieng