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Audencel is a dendritic cell (DC)-based cellular cancer immunotherapy against glioblastoma multiforme (GBM). It is characterized by loading of DCs with autologous whole tumor lysate and in vitro maturation via “danger signals”. The recent phase II “GBM-Vax” trial showed no clinical efficacy for Audencel as assessed with progression-free and overall survival in all patients. Here we present immunological research accompanying the trial with a focus on immune system factors related to outcome and Audencel’s effect on the immune system. Methodologically, peripheral blood samples (from apheresis before Audencel or venipuncture during Audencel) were subjected to functional characterization via enzyme-linked immunospot (ELISPOT) assays connected with cytokine bead assays (CBAs) as well as phenotypical characterization via flow cytometry and mRNA quantification. GBM tissue samples (from surgery) were subjected to T cell receptor sequencing and immunohistochemistry. As results we found: Patients with favorable pre-existing anti-tumor characteristics lived longer under Audencel than Audencel patients without them. Pre-vaccination blood CD8+ T cell count and ELISPOT Granzyme B production capacity in vitro upon tumor antigen exposure were significantly correlated with overall survival. Despite Audencel’s general failure to induce a significant clinical response, it nevertheless seemed to have an effect on the immune system. For instance, Audencel led to a significant up-regulation of the Th1-related immunovariables ELISPOT IFNγ, the transcription factor T-bet in the blood and ELISPOT IL-2 in a dose-dependent manner upon vaccination. Post-vaccination levels of ELISPOT IFNγ and CD8+ cells in the blood were indicative of a significantly better survival. In summary, Audencel failed to reach an improvement of survival in the recent phase II clinical trial. No clinical efficacy was registered. Our concomitant immunological work presented here indicates that outcome under Audencel was influenced by the state of the immune system. On the other hand, Audencel also seemed to have stimulated the immune system. Overall, these immunological considerations suggest that DC immunotherapy against glioblastoma should be studied further – with the goal of translating an apparent immunological response into a clinical response. Future research should concentrate on investigating augmentation of immune reactions through combination therapies or on developing meaningful biomarkers. Electronic supplementary material The online version of this article (10.1186/s40478-018-0621-2) contains supplementary material, which is available to authorized users.

Dendritic cells (DCs) are antigen-presenting cells that are capable of priming anti-tumor immune responses, thus serving as attractive tools to generate tumor vaccines. In this multicentric randomized open-label phase II study, we investigated the efficacy of vaccination with tumor lysate-charged autologous DCs (Audencel) in newly diagnosed glioblastoma multiforme (GBM). Patients aged 18 to 70 years with histologically proven primary GBM and resection of at least 70% were randomized 1:1 to standard of care (SOC) or SOC plus vaccination (weekly intranodal application in weeks seven to 10, followed by monthly intervals). The primary endpoint was progression-free survival at 12 months. Secondary endpoints were overall survival, safety, and toxicity. Seventy-six adult patients were analyzed in this study. Vaccinations were given for seven (3&ndash, 20) months on average. No severe toxicity was attributable to vaccination. Seven patients showed flu-like symptoms, and six patients developed local skin reactions. Progression-free survival at 12 months did not differ significantly between the control and vaccine groups (28.4% versus 24.5%, p = 0.9975). Median overall survival was similar with 18.3 months (vaccine: 564 days, 95% CI: 436&ndash, 671 versus control: 568 days, 95% CI: 349&ndash, 680, p = 0.89, harzard ratio (HR) 0.99). Hence, in this trial, the clinical outcomes of patients with primary GBM could not be improved by the addition of Audencel to SOC.

Anagrelide hydrochloride is an anti-thrombotic agent indicated for the treatment of essential thrombocythemia (ET). In various previously published clinical trials of 2 branded formulations of anagrelide in patients with ET at high risk for thrombohemorrhagic events, the rates of adverse events and discontinuation were strikingly divergent between brands. Because the formulations and manufacturers differed, the differences in tolerability, as well as platelet counts, might have been related to differences in pharmacokinetic properties between the 2 formulations.The present series of investigations (1) determined the pharmacokinetic profile of anagrelide and its metabolites; (2) compared the pharmacokinetic profiles of the test and reference formulations of anagrelide; (3) investigated the in vitro release of anagrelide as a marker of intragastric anagrelide release of the test and reference formulations; and (4) compared the platelet-reducing effects of the test and reference formulations in patients with thrombocythemia in 2 longitudinal studies over 4 weeks.A series of 4 in vivo studies and 1 in vitro study were conducted. In a pilot, prospective, singledose study in healthy volunteers, the pharmacokinetic properties (C(max), T(max), and AUC(0-infinity)) of a test formulation of anagrelide were assessed using high-performance liquid chromatography analysis of plasma samples. Based on the results from that study, a single-dose, randomized, double-blind, 2-period crossover study in healthy volunteers was conducted to determine bioequivalence of 2 formulations of anagrelide 2 mg/d (taken as 4 capsules). In vitro dissolution properties of the test or reference formulation containing 0.5 mg anagrelide as the active ingredient were studied in an assay mimicking gastrointestinal release. To test for effects on platelet counts of switching from the reference formulation (previous treatment on stable dose for 3 months) to the test formulation, two 4-week longitudinal trials were conducted: one in patients with ET (in Germany), and one in patients with thrombocythemia associated with chronic myeloproliferative disorders (CMPDs) (in Austria).The pilot pharmacokinetic study of the test formulation in 16 volunteers (10 women, 6 men; mean [SD] age, 20.5 [1.5] years; weight, 69.0 [10.0 kg) suggested that anagrelide was metabolized to 3-hydroxyanagrelide (AUC(0-infinity) 50% compared with anagrelide) and the inactive metabolite 2-amino-5,6-dichloro-,4-dihydroquinazolone. The subsequent bioequivalence study in 24 volunteers (14 women, 10 men; mean [SD] age, 23 [4] years; white, 100%; weight, 67.5 [10.2] kg) found that the test formulation was associated with a significantly lower C(max) (point estimation [PE], 66%; 90% CI, 58%-76%; P0.001) and AUC(0-infinity) (PE, 77%; 90% CI, 68%-86%; P = 0.001). T(max) values for anagrelide and 3-hydroxyanagrelide were 1 hour longer with the test formulation compared with the reference formulation. The total number of adverse events with the reference formulation was 46; the test formulation, 29 (P = 0.05). In vitro, anagrelide from the reference formulation was immediately released (89.1% at 5 minutes), whereas there was a delayed release (93.6% at 30 minutes) from the test formulation (P0.05). In the last 2 studies, 2 cohorts of white patients (cohort 1, 15 patients with ET; 10 women, 5 men; mean [SD] age, 49.0 [10.7] years [range, 31-66 years]; weight, 73.2 [12.6] kg; cohort 2, 19 patients with thrombocythemia associated with CMPD; 12 women, 7 men; age, 62.6 [12.4] years [range, 38-80 years]; weight, 66.1 [13.3] kg) who had received treatment foror =3 months with the reference formulation were switched to the same dose of the test formulation and maintained on this dose for 4 weeks. Platelet counts did not change significantly from baseline over 4 weeks and stayed within a predefined margin of 150 x 10(3) cells/microL.The pharmacokinetic properties, adverse event rates, and in vitro dissolution profile differed between the test and reference anagrelide formulations in these healthy volunteers. In patients with ET or thrombocythemia associated with CMPD, platelet counts did not differ significantly from baseline at 4 weeks when subjects were switched from the reference to the test anagrelide formulation.

Alcoholism is a chronic and potentially fatal disease. One of the therapeutic options is pharmacotherapy with the opioid antagonist naltrexone in combination with psychotherapy.The objective of this review was to compare the clinical effectiveness of naltrexone (50 mg/day) versus that of a placebo in alcohol-dependent patients receiving psychotherapy.The clinical effectiveness of the treatment was assessed in accordance with the principles of systematic review, as outlined in the Cochrane Collaboration guidelines (Cochrane Reviewer's Handbook) and the guidelines of the Polish Agency for Health Technology Assessment (AHTAPol).Statistical significances in favor of the treatment modality were found in both the percentage of patients maintaining total abstinence and the percentage of relapsed patients.The analysis herein demonstrates that for short (12-16 weeks) period of treatment, a combination of naltrexone administration and psychotherapy results in high clinical efficacy with a safety profile comparable to that of the placebo in the treatment of alcohol-dependent patients. The side effects of naltrexone treatment are usually mild and transient.