Therapeutic Dose Range Research Articles

A dose-escalating toxicology study of the candidate biologic ELP-VEGF

Vascular Endothelial Growth Factor (VEGF), a key mediator of angiogenesis and vascular repair, is reduced in chronic ischemic renal diseases, leading to microvascular rarefaction and deterioration of renal function. We developed a chimeric fusion of human VEGF-A121 with the carrier protein Elastin-like Polypeptide (ELP-VEGF) to induce therapeutic angiogenesis via targeted renal VEGF therapy. We previously showed that ELP-VEGF improves renal vascular density, renal fibrosis, and renal function in swine models of chronic renal diseases. However, VEGF is a potent cytokine that induces angiogenesis and increases vascular permeability, which could cause undesired off-target effects or be deleterious in a patient with a solid tumor. Therefore, the current study aims to define the toxicological profile of ELP-VEGF and assess its risk for exacerbating tumor progression and vascularity using rodent models. A dose escalating toxicology assessment of ELP-VEGF was performed by administering a bolus intravenous injection at doses ranging from 0.1 to 200 mg/kg in Sprague Dawley (SD) rats. Blood pressure, body weight, and glomerular filtration rate (GFR) were quantified longitudinally, and terminal blood sampling and renal vascular density measurements were made 14 days after treatment. Additionally, the effects of a single administration of ELP-VEGF (0.1–10 mg/kg) on tumor growth rate, mass, and vascular density were examined in a mouse model of breast cancer. At doses up to 200 mg/kg, ELP-VEGF had no effect on body weight, caused no changes in plasma or urinary markers of renal injury, and did not induce renal fibrosis or other histopathological findings in SD rats. At the highest doses (100–200 mg/kg), ELP-VEGF caused an acute, transient hypotension (30 min), increased GFR, and reduced renal microvascular density 14 days after injection. In a mouse tumor model, ELP-VEGF did not affect tumor growth rate or tumor mass, but analysis of tumor vascular density by micro-computed tomography (μCT) revealed significant, dose dependent increases in tumor vascularity after ELP-VEGF administration. ELP-VEGF did not induce toxicity in the therapeutic dosing range, and doses one hundred times higher than the expected maximum therapeutic dose were needed to observe any adverse signs in rats. In breast tumor—bearing mice, ELP-VEGF therapy induced a dose-dependent increase in tumor vascularity, demanding caution for potential use in a patient suffering from kidney disease but with known or suspected malignancy.

Acute administration of oxycodone, alcohol, and their combination on simulated driving-preliminary outcomes in healthy adults.

Epidemiological data indicate that drivers testing positive for an opioid drug are twice as likely to cause a fatal car crash; however, there are limited controlled data available. The primary aim of this study was to assess the effects of a therapeutic dose range of oxycodone alone and in combination with alcohol on simulated driving performance. Healthy participants (n = 10) completed this within-subject, double-blind, placebo-controlled, randomized outpatient study. Six 7-h sessions were completed during which oxycodone (0, 5, 10 mg, p.o.) was administered 30 min before alcohol (0, 0.8 g/kg (15% less for women), p.o.) for a total of 6 test conditions. Driving assessments and participant-, observer-rated, psychomotor and physiological measures were collected in regular intervals before and after drug administration. Oxycodone alone (5, 10 mg) did not produce any changes in driving outcomes or psychomotor task performance, relative to placebo (p > 0.05); however, 10 mg oxycodone produced increases in an array of subjective ratings, including sedation and impairment (p < 0.05). Alcohol alone produced driving impairment (e.g., decreased lateral control) (p < 0.05); however, oxycodone did not potentiate alcohol-related driving or subjective effects. These preliminary data suggest that acute doses of oxycodone (5, 10 mg) do not significantly impair acuity on laboratory-based simulated driving models; however, 10 mg oxycodone produced increases in self-reported outcomes that are not compatible with safe driving behavior (e.g., sedation, impairment). Additional controlled research is needed to determine how opioid misuse (higher doses; parenteral routes of administration) impacts driving risk.

Inhibition of Fibrotic Contraction by Sirolimus (Rapamycin) in an Ex Vivo Model of Thyroid Eye Disease.

Thyroid eye disease (TED) is characterized by orbital inflammation and complicated by extraocular muscle fibrosis. Treatment with rapamycin/sirolimus has been reported to improve ocular motility and disease manifestations in TED. Whether this resulted from a primary antifibrotic effect on fibroblasts or was secondary to immune-suppression is unclear. In vitro contractility studies of primary orbital fibroblasts. Cells from patients with TED and controls were treated with rapamycin [mechanistic target of rapamycin an (mTOR) inhibitor] and MHY1485 (an mTOR stimulator) as well as inhibitors upstream in the same signaling cascade (saracatinib and befatinib). At concentrations consistent with the therapeutic dosing range in humans, rapamycin/sirolimus significantly reduces fibrosis in orbital fibroblasts from TED patients and controls in vitro. This effect is separate from, and in addition to, its immune suppressive effect. mTOR-driven fibrotic activity is greater in TED-derived fibroblasts and can be blocked also upstream of mTOR by inhibition of src. There was no adverse effect on cell survival. The authors present evidence for a direct antifibrotic effect of rapamycin/sirolimus in primary orbital fibroblasts. Targeting mTOR signaling presents a further and adjunctive treatment of TED alongside other immune-suppressive agents. By acting downstream of IGF1-R, sirolimus may offer a cost-effective alternative to teprotumumab therapy. Clinical case reports, now supplemented by this in vitro evidence, support the initiation of a clinical trial to treat the fibrotic sequelae of TED with this already-approved agent. Such an "off-the-shelf" therapy is a welcome prospect for TED treatment, particularly one available at a low price.

Potential properties of L-Asparagine for ESR dosimetry applications

Radiation-induced free radicals in x-ray irradiated L-asparagine have been investigated by Electron Spin Resonance (ESR) spectroscopy, for dosimetric purposes. Optimal signal-to-noise (S/N) ratio and signal intensity for ESR spectra were found for a microwave power of 2 mW, and modulation amplitude of 1 mT. The dosimetric properties of L-asparagine are characterized by a linear dose-response in the therapeutic dose range, and lowest detectable dose was 0.1 Gy, including a small energy dependence (80 KV-6 MV), dose rate independence over a range of clinical relevance (100–600 cGy/min). The ESR signal stability was also investigated in the period of 6 months at room temperature. No changes in the signal intensity were observed over this period. Therefore, we propose L-asparagine as a potential candidate for electron spin resonance dosimetry of ionizing radiation.

Celastrol Efficacy by Oral Administration in the Adjuvant-Induced Arthritis Model.

Background: We previously demonstrated that celastrol has significant anti-inflammatory and bone protective effects when administered via the intraperitoneal route. For further preclinical evaluation, an effective oral administration of celastrol is crucial. Here we aimed to study the therapeutic dose range for its oral administration.Methods: Celastrol (1–25 μg/g/day, N = 5/group) was administrated orally to female adjuvant-induced arthritis (AIA) rats after 8 days of disease induction for a period of 14 days. A group of healthy (N = 8) and arthritic (N = 15) gender- and age-matched Wistar rats was used as controls. During the treatment period, the inflammatory score, ankle perimeter, and body weight were measured. At the end of the treatment, the animals were sacrificed, blood was collected for clinical pathology, necropsy was performed with collection of internal organs for histopathological analysis, and paw samples were used for disease scoring.Results: Doses higher than 2.5 μg/g/day of celastrol reduced the inflammatory score and ankle swelling, preserved joint structure, halted bone destruction, and diminished the number of synovial CD68+ macrophages. Bone resorption and turnover were also reduced at 5 and 7.5 μg/g/day doses. However, the dose of 7.5 μg/g/day was associated with thymic and liver lesions, and higher doses showed severe toxicity.Conclusion: Oral administration of celastrol above 2.5 μg/g/day ameliorates arthritis. This data supports and gives relevant information for the development of a preclinical test of celastrol in the setting of a chronic model of arthritis since rheumatoid arthritis is a long-term disease.

Venlafaxine poisoning-induced severe hypoglycemia in a non-diabetic patient: a case report

Abstract Introduction: Venlafaxine is a serotonin and norepinephrine reuptake inhibitor (SNRI) used to treat major depressive episodes and anxiety. The risk of hypoglycemia is mentioned in the Summary of Product Characteristics (SmPC) of venlafaxine in the “warnings and precautions” section in diabetic patients. This effect appears neither in the “adverse reactions” nor in the “overdose” section. We herein report a case of severe hypoglycemia with coma in relation to venlafaxine poisoning. Case Report: A 35-year-old non-diabetic obese woman (BMI, 29 kg/m2) was found unconscious a few hours after ingesting venlafaxine and bromazepam in a suicide attempt. Vital signs on day 1 were as follows: Glasgow Coma score of 7, blood pressure of 99/66 mmHg and heart rate of 100/min. Electrocardiogram showed no abnormality. She was admitted to the intensive care unit. Due to sustained hypoglycemia [0.5 g/L (day1); 0.41 g/L (day2); 0.8 to 1.20 (day3)], she received continuous intravenous 10% glucose infusion for 3 days to normalize blood glucose. Plasma venlafaxine concentration was 11.7 times the upper the limit of therapeutic dose range (UTDR) on day 2 and reached the therapeutic dose range (TDR) on day 6. Plasma bromazepam concentration was 6.7 times UTDR on day 3 and reached TDR on day 8. Alternative etiologies of hypoglycemia were excluded, i.e. hypoglycemic sulfonamide, insulin poisoning, insulinoma, and disease of the adrenal gland, liver and thyroid. She was transferred to a psychiatric unit after one week. Discussion: Impairment of blood glucose homeostasis is rarely described with venlafaxine. In our patient, hypoglycemia appeared to be correlated with plasma venlafaxine concentrations and may be explained by increased insulin sensitivity, considering her obesity. Conclusion: Healthcare professionals should be aware of hypoglycemia induced by venlafaxine or other SNRIs in non-diabetic patients.

Abstract 2273: Selection of first-in-human clinical dose range for the tumor-targeted 4-1BB agonist MP0310 (AMG 506) using a pharmacokinetic/pharmacodynamics modeling approach

Abstract Following the clinical success of checkpoint inhibitors, cancer immunotherapy is rapidly expanding into combination treatments to enhance response rates and duration. Engagement of co-stimulatory molecules from the tumor necrosis factor receptor (TNFR) superfamily, including 4-1BB, may be a promising approach to enhance the benefits of cancer immunotherapy. Agonistic antibodies against the costimulatory receptor 4-1BB (CD137) have been shown to effectively enhance the anti-tumor activity of checkpoint inhibitors and other agents in preclinical animal models. However, the clinical development of 4-1BB agonistic antibodies has met with limited success thus far. Anti-4-1BB monoclonal antibodies have either been reported to cause significant dose-limiting hepatotoxicity or demonstrated limited efficacy as single agent therapeutics. We generated a DARPin® therapeutic candidate, MP0310 (AMG 506), which comprises domains binding to 4-1BB and fibroblast activation protein (FAP). MP0310 triggers 4-1BB activation only if bound and clustered via FAP which is abundantly expressed by cancer associated fibroblasts present in many solid tumors. In vitro functional assays indicate that MP0310 is a potent T cell co-stimulator in the presence of FAP-expressing cells. In vivo activity of tumor-targeted 4-1BB agonism was assessed in the HT-29 colon carcinoma xenograft model in PBMC humanized mice in combination with a T cell engager. Consistent with tumor targeting, MP0310 enhanced intra-tumoral CD8 T cell expansion while showing only limited systemic activity. We used a translational pharmacokinetic-pharmacodynamic (PK-PD) modeling approach to integrate in vitro and in vivo data to support the estimation of a minimal anticipated biological effect level (MABEL) and the relevant dose range for first in human (FIH) studies. In addition to a PK model describing the MP0310 concentrations over time in mouse and monkey, direct and indirect response models were used to describe receptor occupancy (RO), intra-tumoral CD8 T cell infiltration and peripheral CD8 count kinetics. Predictions from the combined PK and PD models using average intra-tumoral and peripheral drug concentrations (Cav) provide a MABEL dose with minimal expected systemic PD effects at 20% RO as well as the anticipated therapeutic dose range in humans. In conclusion, our PK/PD-modeling approach provides support for the selection of a safe starting dose for MP0310 (AMG506) in patients. It provides a rationale for selecting the maximum tested dose, and may help reduce the number of cancer patients receiving sub-therapeutic doses. MP0310 (AMG 506) is currently being evaluated in a Ph1 clinical study. Citation Format: Alexander Link, Laurent Juglair, Heïdi Poulet, Guy Lemaillet, Christian Reichen, Patricia Schildknecht, Ivana Tosevski, Joanna Robinson, Niina Veitonmäki, Jörg Herbst, Keith Dawson, Christof Zitt, Camila de Almeida, Rik de Greef, Victor Levitsky, Michael T. Stumpp, Hong Ji, Elmar Vom Baur. Selection of first-in-human clinical dose range for the tumor-targeted 4-1BB agonist MP0310 (AMG 506) using a pharmacokinetic/pharmacodynamics modeling approach [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 2273.

Evaluation of Long-Time Decoction-Detoxicated Hei-Shun-Pian (Processed Aconitum carmichaeli Debeaux Lateral Root With Peel) for Its Acute Toxicity and Therapeutic Effect on Mono-Iodoacetate Induced Osteoarthritis.

BackgroundAs a degenerative joint disease with severe cartilage destruction and pain, osteoarthritis (OA) has no satisfactory therapy to date. In traditional Chinese medicine (TCM), Aconitum carmichaeli Debeaux derived Hei-shun-pian (Hsp) has been developed for joint pain treatment. However, it causes adverse events in OA patients. Long-time decoction has been traditionally applied to reduce the aconite toxicity of Hsp and other aconite herbs, but its detoxifying effect is uncertain.Methods Hsp was extracted with dilute decoction times (30, 60, and 120 min) and evaluated by toxicological, chemical, pharmacological assays. Acute toxicity assay and chemical analysis were employed to determine the toxicity and chemoprofile of Hsp extracts, respectively. Since the detoxified Hsp (dHsp) was defined, its therapeutic effect was evaluated by using an OA rat model induced by monosodium iodoacetate. dHsp at 14 g/kg was orally administered for 28 days, and the pain assessments (mechanical withdrawal threshold and thermal withdrawal latency) and histopathological analyses (HE and safranin-O staining) were performed. Real-time PCR (qPCR) was applied to determine the molecular actions of dHsp on cartilage tissue and on chondrocytes. MTT assay was conducted to evaluate the effect of dHsp on the cell viability of chondrocytes. The cellular and molecular assays were also conducted to analyze the functions of chemical components in dHsp.ResultsThe chemoprofile result showed that the contents of toxic alkaloids (aconitine, mesaconitine, and hypaconitine) were decreased but that of non-toxic alkaloids (benzoylaconitine, benzoylmesaconitine, and benzoylhypaconitine) were increased with increasing decoction time. Acute toxicity assay showed that only Hsp extract with 120 min decoction was non-toxic within the therapeutic dose range. Thus, it was defined as dHsp for further experiment. In OA experiment, dHsp significantly attenuated joint pain and prevented articular degeneration from MIA attack. qPCR data showed that dHsp restored the abnormal expressions of Col10, Mmp2, Sox5, Adamts4/5/9, and up-regulated Col2 expression in rat cartilage. In vitro, dHsp-containing serum significantly proliferated rat chondrocytes and regulated the gene expressions of Col2, Mmp1, Adamts9, and Aggrecan in a similar way as the in vivo data. Moreover, aconitine, mesaconitine, and hypaconitine exerted cytotoxic effects on chondrocytes, while benzoylaconitine and benzoylhypaconitine except benzoylmesaconitine exhibited similar molecular actions to dHsp, indicating contributions of benzoylaconitine and benzoylhypaconitine to dHsp.ConclusionsThis study defined dHsp and demonstrated dHsp as a potential analgesic and disease modifying agent against OA with molecular actions on the suppression of chondrocyte hypertrophy and extracellular matrix degradation, providing a promising TCM candidate for OA therapy.

Opioid receptors and butorphanol dependence

Butorphanol, a mixed opioid agonist/antagonist, is considered to be a relatively safe drug when used within the therapeutic dose range. However, diversional uses of butorphanol involving high dose have been documented. In the present review, the relative involvement of μ, δ, and κ-opioid receptors in butorphanol physical dependence in rats is discussed. Physical dependence was produced by continuous intracerebroventricular (icv) infusion of butorphanol (26 nmol/h) for 72 h in male Sprague-Dawley rats. Multiple icv injections of β-funaltrexamine (β-FNA, a μ-antagonist, 12, 24, or 48 nmol/5 μl), naltrindole (NTI, a δ-antagonist, 0.1, 1, or 10 nmol/5 μl), or nor-binaltorphimine (nor-BNI, a κ-antagonist, 12, 24, or 48 nmol/5 μl) significantly attenuated the development of butorphanol dependence. Furthermore, icv administration of both NTI (24, 48, or 100 nmol/5 μl) and nor-BNI (3, 10, 20, 48 or 100 nmol/5 μl) precipitated withdrawal behaviors, whereas, β-FNA (12, 24, 48, or 100 nmol/5 μl) was unable to elicit withdrawal signs in butorphanol-dependent rats. The results indicate that the development of butorphanol dependence is due to effects of butorphanol on central μ-, δ-, and κ-opioid receptors.

Effects of Simvastatin on the Metabolism of Fatty Acids in Combined Secondary Prevention of Coronary Heart Disease: Dosage and Gender Differences between the Effects

Statins are currently used for secondary prevention of Coronary Heart Disease (CHD), as the lipid-lowering therapy with them is proven safe and effective. The purpose of this research is to investigate the dose-dependent effect of statins used for secondary prevention of coronary heart disease, as well as mechanisms of quantitative and qualitative changes in lipoproteins, fatty acids and cholesterol in the blood and tissues of people of both sexes. In a clinical trial (n=125, of which 89 patients belong to group 1 and 36 to group 2) and an experiment on laboratory animals (n = 100), simvastatin reduced the total level of fatty acids in blood plasma, when given in the amount that was within the therapeutic dose range. This effect was achieved through a drug-induced improvement in the capacity of hepatic cells to absorb Low-density (LDL) and Very-low-density (VLDL) lipoproteins. Considering the formation of saturated fatty acids, statin performed better in males. With Omega-3 polyunsaturated fatty acids involved, changes in lipoproteins, cholesterol and fatty acids (liver and myocardium) were similar to those caused by small doses of a statin drug. Effects of the combination of bisoprolol and acetylsalicylic acid were completely different from those caused by the use of statin.

Comparative efficacy of 20 graft-versus-host disease prophylaxis therapies for patients after hematopoietic stem-cell transplantation: A multiple-treatments network meta-analysis.

Graft-versus-host disease (GVHD) is a leading cause of death in patients after hematopoietic stem-cell transplantation (HSCT). Previous studies have shown different efficacy of GVHD prophylaxis therapies. We reviewed 46 randomized controlled trials (including 8050 participants) systematically from Jun 20, 2004 to Aug 20, 2019. These investigations compared the following drugs or their combination at therapeutic dose range for GVHD after HSCT. The main results were based on the proportion of patients who respond to these therapies. Cyclosporine + methotrexate + Anti-T cell globulin (ATG), tacrolimus + methotrexate + ATG, tacrolimus + bortezomib + sirolimus and cyclosporine + marrow mesenchymal stem cells (MMSCs) were significantly more efficacious than corticosteroids alone (OR: 12.15, 6.71, 6.25, 3.73). corticosteroids alone were less efficacious than all the other GVHD prophylaxis therapies tested. Cyclosporine + methotrexate + ATG may be the best choice when starting treatment for GVHD.

Pharmacokinetics and Dose Proportionality of Betahistine in Healthy Individuals

Betahistine dihydrochloride is widely used to reduce the severity and frequency of vertigo attacks associated with Ménière’s disease. Betahistine is an analogue of histamine, and is a weak histamine H1 receptor agonist and potent histamine H3 receptor antagonist. The recommended therapeutic dose for adults ranges from 24 to 48 mg given in doses divided throughout the day. Betahistine undergoes extensive first-pass metabolism to the major inactive metabolite 2-pyridyl acetic acid (2PAA), which can be considered a surrogate index for quantitation of the parent drug due to extremely low plasma levels of betahistine. The aim of the present investigation was to assess the pharmacokinetics and dose proportionality of betahistine in Arabic healthy adult male subjects under fasting conditions. A single dose of betahistine in the form of a 8, 16, or 24 mg tablet was administered to 36 subjects in randomized, cross-over, three-period, three-sequence design separated by a one week washout period between dosing. The pharmacokinetic parameters Cmax, AUC0–t, AUC0–∞, Tmax, and Thalf were calculated for each subject from concentrations of 2-PAA in plasma, applying non-compartmental analysis. The current study demonstrated that betahistine showed linear pharmacokinetics (dose proportionality) in an Arabic population over the investigated therapeutic dose range of 8–24 mg.

A10 TR1 CELL-BASED THERAPY FOR INFLAMMATORY ILEITIS IN SHIP-/- MICE

Abstract Background Crohn’s disease (CD), a form of inflammatory bowel disease (IBD), is characterized by chronic inflammation that can occur anywhere along the gastrointestinal (GI) tract, but commonly involves the distal portion of the ileum. Src homology 2 (SH2) domain-containing inositol polyphosphate 5-phosphatase 1 (SHIP) is a hematopoietic-specific regulator of secondary signals generated by the PI3K pathway and regulates immune activation. SHIP-/- mice, at 6–8 weeks of age, spontaneously develop inflammatory ileitis due to myeloid proliferation, a lack of T cells, and an increase in IL-1β. Aims Here we investigated the efficacy of type 1 regulatory T (Tr1) cells, which are characterized by high IL-10 production, a broadly acting anti-inflammatory cytokine that promotes gut homeostasis, to treat ileitis in SHIP-/- mice. Methods Using IL-10GFPFOXP3RFP B6 reporter mice, we sorted FOXP3-CD44High Tr1 cells, FOXP3+ Tregs, and FOXP3-CD44Low naive T cells from total CD4+ T cells, and cultured them with immobilized α-CD3, soluble α-CD28 and recombinant IL-2 for 3 days. Naive T cells were grown in undifferentiated conditions or polarized to Th1 or Th17 cells. Cell phenotypes were characterized by ELISA and flow cytometry. For the adoptive Tr1 cell transfer, CD44High cells were sorted from FOXP3GFP Thy1.1 reporter mice and cultured as above with an additional 2 days’ rest in the presence of IL-2 alone. SHIP-/- mice and wild type (WT) littermates were sublethally irradiated at 5 weeks of age, followed 24h later by IP injection with 0.7 – 1.0 x 106 Tr1 cells or PBS vehicle. At 7 weeks of age, mice were euthanized and blood, mesenteric lymph nodes (MLNs), and ileal tissue were processed. Results After 3 days of stimulation, FOXP3-CD44High Tr1 cells produced more IL-10 than Tregs and less IFN-γ than Th1 cells. Additionally, CD44High cells had higher co-expression of CD49b and Lag3, biomarkers for Tr1 cells, in comparison to nT cells, Tregs, Th1, and Th17 cells, a higher percentages of IL-10 producing cells than FOXP3+ Tregs and produced less IFN-γ, IL-17, and TNF-α in comparison to Th1, Th17 and naive T cells, respectively. We found that Tr1 cells successfully engrafted irradiated SHIP-/- mice. Furthermore, engrafted Tr1 cells had high co-expression of CD49b and Lag3, with the majority of these cells located in the MLNs and spleen. SHIP KO mice that received Tr1 cells had comparable ileal length and appearance to SHIP WT, and significantly longer ilea versus SHIP PBS controls — indicating decreased inflammation as a result of successful engraftment. Conclusions In conclusion, ex-vivo expansion and adoptive transfer of Tr1 cells to SHIP-/- mice led to cellular engraftment and improvement in spontaneous ileitis. Hence, Tr1 cellular therapy shows promise as a therapeutic approach in CD. Future experiments will be needed to determine the therapeutic dose range of Tr1 cells and the mechanisms of protection. Funding Agencies CCC

Safety and tolerability of adjunctive brivaracetam in epilepsy: In-depth pooled analysis

ObjectiveThe objective of this analysis was to provide a comprehensive analysis of safety data for adjunctive brivaracetam (BRV), an antiepileptic drug (AED) of the racetam class, for treatment of focal seizures in patients with epilepsy. MethodsData were pooled from two phase II, placebo-controlled, double-blind, dose-ranging trials (N01114 [ClinicalTrials.gov: NCT00175929], N01193 [NCT00175825]) and three phase III, placebo-controlled, double-blind, 12-week trials (N01252 [NCT00490035], N01253 [NCT00464269], and N01358 [NCT01261325]) in patients aged ≥16 years with focal seizures, as well as a phase III, placebo-controlled, double-blind, 16-week trial in patients aged ≥16 years with focal or generalized epilepsy (N01254 [NCT00504881]). Data are presented for the approved therapeutic dose range of 50–200 mg/day. Data for BRV administered intravenously (25–150 mg doses) were pooled separately from one phase III trial (N01258 NCT01405508]) and two clinical pharmacology trials (N01256 [Part B] [UCB Pharma, data on file]; EP0007 [NCT01796899]). Adverse events (AEs) of interest were summarized in relevant categories. ResultsThe safety pool comprised 1957 patients: 1271 receiving adjunctive BRV and 686 receiving placebo. Overall, the incidence of treatment-emergent adverse events (TEAEs) was 66.9% with BRV versus 62.8% with placebo. The most frequently reported TEAEs with BRV (≥5% of patients) versus placebo were somnolence (13.3% vs. 7.9%), headache (10.5% vs. 11.5%), dizziness (10.0% vs. 7.0%), and fatigue (8.2% vs. 4.2%). Incidence of psychiatric disorder-related TEAEs was 11.3% with BRV versus 8.2% with placebo. Behavioral disorder-related TEAE incidence was low (4.0% with BRV vs. 2.5% with placebo). Irritability was reported in 2.7% of BRV-treated patients vs. 1.5% of patients receiving placebo; anger, aggression, and agitation were each reported by ≤1% of patients receiving BRV. Treatment-emergent adverse events potentially associated with psychosis were psychotic disorder (three patients on BRV vs. two patients on placebo), auditory hallucination, illusion, visual hallucination (one patient each on BRV), epileptic psychosis, and hallucination (one patient each on placebo). No additional safety concerns were identified in patients with intravenous (IV) BRV administration (n = 104). ConclusionsThese safety data for adjunctive BRV support its acceptable safety and tolerability profile.

Effects of Immunosuppressive Medications on Mitochondrial Function

BackgroundImmunosuppressive medications are widely used for the prevention of allograft rejection in transplantation and graft-versus-host disease after allogeneic hematopoietic stem cell transplantation. Despite their clinical utility, these medications are accompanied by multiple off-target effects, some of which may be mediated by their effects on mitochondria. MethodsWe examined the effect of commonly used immunosuppressive reagents, mycophenolate mofetil (MMF), cyclosporine A (CsA), rapamycin, and tacrolimus on mitochondrial function in human T-cells. T-cells were cultured in the presence of immunosuppressive medications in a range of therapeutic doses. After incubation, mitochondrial membrane potential, reactive oxygen species (ROS) production, and apoptotic cell death were measured by flow cytometry after staining with DiOC6, MitoSOX Red, and Annexin V and 7-AAD, respectively. Increases in cytosolic cytochrome c were demonstrated by Western blot. T-cell basal oxygen consumption rates were measured using a Seahorse bioanalyzer. ResultsT-cells demonstrated significant levels of mitochondrial depolarization after treatment with therapeutic levels of MMF but not after treatment with CsA, tacrolimus, or rapamycin. Only MMF induced T-cell ROS production and induced significant levels of apoptotic cell death that were associated with increased levels of cytosolic cytochrome c. MMF decreased T-cell basal oxygen consumption within its therapeutic range, and CsA demonstrated a trend toward this result. ConclusionsThe impairment of mitochondrial function by commonly used immunosuppressive reagents may impair T-cell differentiation and function by decreasing energy production, producing toxic ROS, and inducing apoptotic cell death.

Colchicine-induced pancreatitis in an elderly patient with renal impairment: A case report

Colchicine is widely used in the treatment of acute gout. It has a narrow therapeutic window and can be extremely toxic in vulnerable older patients especially those with renal impairment. The most common side effects are gastrointestinal related, such as nausea, vomiting, diarrhea and abdominal pain. Colchicine-induced acute pancreatitis is very rare especially within therapeutic dose range. We report an atypical presentation of acute pancreatitis caused by a therapeutic dose of colchicine in an elderly patient with preexisting chronic renal disease.

Efficacy of Gemcitabine on Intracranial Erlich Tumor and its Determinants

Gemcitabine is quite effective in the treatment of brain tumors, although this drug has a limited ability to overcome the blood-brain barrier (BBB). Aim of study is to assess the therapeutic efficacy of gemcitabine and other drugs with different permeability of BBB in the model of intracranial tumor. The therapeutic activity of gemcitabine, carmustine, cyclophosphamide and cisplatin was studied in mice with intracranially implanted Ehrlich tumor, and also gemcitabine in various doses - with intramuscularly implanted tumor. On intracranial tumor model gemcitabine (25 mg/kg) increased the life span (ILS) by 60-89% (p<0.001), despite the fact that its permeability of the BBB is about 10%. Therapeutic activity of carmustine, cyclophosphamide and cisplatin (ILS were 44, 22 and 11%, respectively) corresponds with the BBB permeability for these drugs (90, 20 and 8%, respectively). On intramuscular tumor model, gemcitabine showed significant antitumor effect at both 25 and 2.5 mg/kg, indicating a wide range of therapeutic doses of this drug. Pronounced therapeutic effect of gemcitabine on intracranial tumor most likely is due to the small but sufficient concentration of the drug that overcomes the BBB.

Combining biorelevant in vitro and in silico tools to simulate and better understand the in vivo performance of a nano-sized formulation of aprepitant in the fasted and fed states

IntroductionWhen developing bio-enabling formulations, innovative tools are required to understand and predict in vivo performance and may facilitate approval by regulatory authorities. EMEND® is an example of such a formulation, in which the active pharmaceutical ingredient, aprepitant, is nano-sized. The aims of this study were 1) to characterize the 80 mg and 125 mg EMEND® capsules in vitro using biorelevant tools, 2) to develop and parameterize a physiologically based pharmacokinetic (PBPK) model to simulate and better understand the in vivo performance of EMEND® capsules and 3) to assess which parameters primarily influence the in vivo performance of this formulation across the therapeutic dose range. MethodsSolubility, dissolution and transfer experiments were performed in various biorelevant media simulating the fasted and fed state environment in the gastrointestinal tract. An in silico PBPK model for healthy volunteers was developed in the Simcyp Simulator, informed by the in vitro results and data available from the literature. ResultsIn vitro experiments indicated a large effect of native surfactants on the solubility of aprepitant. Coupling the in vitro results with the PBPK model led to an appropriate simulation of aprepitant plasma concentrations after administration of 80 mg and 125 mg EMEND® capsules in both the fasted and fed states. Parameter Sensitivity Analysis (PSA) was conducted to investigate the effect of several parameters on the in vivo performance of EMEND®. While nano-sizing aprepitant improves its in vivo performance, intestinal solubility remains a barrier to its bioavailability and thus aprepitant should be classified as DCS IIb. ConclusionsThe present study underlines the importance of combining in vitro and in silico biopharmaceutical tools to understand and predict the absorption of this poorly soluble compound from an enabling formulation. The approach can be applied to other poorly soluble compounds to support rational formulation design and to facilitate regulatory assessment of the bio-performance of enabling formulations.

Fingernail dosimetry using electron spin resonance for radiation disaster response

This study investigates the use of electron spin resonance (ESR) signals from human fingernails for retrospective dosimetry as part of radiation disaster response, focusing on the variabilities of individual responses to radiation. Samples of fingernails were collected from 7 adult donors (Asian type) and irradiated to 35 Gy and 70 Gy of gamma-rays from a Cs-137 source at a dose rate of 0.857 Gy/min. All irradiated fingernails were measured for 39 days with an X-band ESR spectrometer and stored in darkness inside the vacuum desiccator (30% humidity, 20°C) in between measurements at all times. All samples were harvested using one specific nail cutter and given no other special treatments. It was observed that the measured radiation-induced signals faded on about 10-12% after 1 day of exposure. Though the signal intensities showed a significant difference among the donors, stronger linearities in the dose responses were observed in the samples of younger donors. From the results obtained in this study, it is expected that fingernails would be a useful tool for retrospective dosimetry in case of an unexpected radiological accident or medical treatment error associated with exposure in therapeutic dose range, as far as the individual-based calibration curves were available. Further investigations will be made to clarify the reason for the different responses by using the fingernail samples taken from a greater number of donors of different ages and lifestyles.

Investigation of the applicability of the ESR nail dosimetry for assessment of accidental exposure in medical facilities

The study of human fingernails as a possible dosimeter has continued to be of interest in the field of accident dosimetry because of its potential advantages. The present study aims to investigate the suitability of fingernails for the assessment of accidental exposure in medical facilities that use radiation for diagnosis or radiation therapy through the electron spin resonance (ESR) dosimetry technique. Relevant drying conditions, sample characteristics, and setup modifications were tested and compared among the samples of three different individuals. Results indicated that 1 h of sample drying inside a heat dryer sterilizer at 100 °C temperature showed good thermal stability of the ESR signals up to 30 days of postmeasurement. Another finding of this study was the effective approach in the signal stability for samples kept under vacuum storage condition with limited exposure to ambient light. While the samples from three different individuals showed unique dose–response curves after the X-ray irradiation, those were quite linear in the therapeutic dose range (up to 70 Gy). These results indicate that fingernails could be useful for the detection of unexpected significant exposure of patients and medical staff handling radiation or radiopharmaceuticals. Further investigations are desirable for standardization of the fingernail dosimetry in medical applications.