Safety and dose-dependency of eptacog beta (activated) in a dose escalation study of non-bleeding congenital haemophilia A or B patients, with or without inhibitors

INTRODUCTION

Varying initial doses of activated eptacog beta (recombinant human FVIIa, rhFVIIa) may provide therapeutic options when treating bleeding in patients with congenital haemophilia who have developed inhibitory antibodies to factor VIII (FVIII) or factor IX (FIX). This study evaluated escalated doses of a new rhFVIIa product as a prelude to selecting the doses for clinical efficacy evaluation in haemophilia patients.

AIM

To assess the safety, pharmacokinetics, and laboratory pharmacodynamics of 3 doses of rhFVIIa in non-bleeding patients with congenital haemophilia A or B with or without inhibitors.

METHODS

Adult male patients (18-75 years old) with congenital haemophilia A or B (with or without inhibitors) received infusions of rhFVIIa at doses of 25, 75 or 225 μg/kg body weight. Ten patients were treated at each dose level, and each patient received 2 different dose levels. Descriptive methods were used to analyse the data.

RESULTS

Administration of rhFVIIa at all doses was well tolerated. Pharmacokinetic analyses showed that peak FVIIa plasma levels (C_max ) were approximately proportional to dose and correlated well with peak thrombin generation. Total AUC_0-inf also was approximately dose proportional. Clot formation and duration correlated with FVIIa activity. Repeat doses did not produce an immunological response.

CONCLUSION

In the first dose-escalation study of rhFVIIa to support product registration, eptacog beta at doses of 25, 75, and 225 μg/kg was pharmacodynamically active and well tolerated in non-bleeding patients with congenital haemophilia A or B.

Topical ionic contra-viral therapy comprised of digoxin and furosemide as a potential novel treatment approach for common warts

Background

DNA viruses such as HPV rely on K⁺ influx for replication. Both digoxin and furosemide inhibit the K⁺ influx by interacting with cell membrane ion co‐transporters (Na⁺/K⁺‐ATPase and Na⁺‐K⁺‐2Cl⁻ co‐transporter‐1, respectively). We therefore hypothesized that these two compounds in a topical formulation may be valuable in the treatment of HPV‐induced warts. This new approach is called Ionic Contra‐Viral Therapy (ICVT).

Objective

To evaluate systemic exposure, safety and tolerability of ICVT with a combination of furosemide and digoxin after repeated topical application in subjects with common warts. Furthermore, we aimed to evaluate pharmacodynamics effects of ICVT.

Methods

Twelve healthy subjects with at least four common warts on their hands were included in the study and treated with a fixed dose of 980 mg topical gel containing 0.125% (w/w) digoxin and 0.125% (w/w) furosemide for 7 consecutive days on their lower back to assess safety and systemic exposure. Two warts were treated with 10 mg each and two served as negative controls to obtain preliminary evidence of treatment effect.

Results

ICVT was well tolerated topically, and there was no evidence of systemic exposure of digoxin or furosemide. There were no clinical relevant safety findings and no serious adverse events (SAEs). A rapid and statistically significant reduction in diameter, height and volume of the warts was already observed at day 14.

Conclusion

ICVT was found to be safe for administration to humans and 7 days of active treatment showed a statistical significant wart reduction compared to untreated control lesions, clearly indicating pharmacological activity.

Correlation Between Preoperative Serum Carcinoembryonic Antigen Levels and Expression on Pancreatic and Rectal Cancer Tissue

Carcinoembryonic antigen (CEA)-targeted imaging and therapeutic agents are being tested in clinical trials. If CEA overexpression in malignant tissue corresponds with elevated serum CEA, serum CEA could assist in selecting patients who may benefit from CEA-targeted agents. This study aims to assess the relationship between serum CEA and CEA expression in pancreatic (n = 20) and rectal cancer tissues (n = 35) using histopathology. According to local laboratory standards, a serum CEA >3 ng/mL was considered elevated. In pancreatic cancer patients a significant correlation between serum CEA and percentage of CEA-expressing tumor cells was observed (P = .04, ρ = .47). All 6 patients with homogeneous CEA expression in the tumor had a serum CEA >3 ng/mL. Most rectal cancer tissues (32/35) showed homogeneous CEA expression, independent of serum CEA levels. This study suggests that selection of pancreatic cancer patients for CEA-targeted agents via serum CEA appears adequate. For selection of rectal cancer patients, serum CEA levels are not informative.

[Fosfomycin, an old antibiotic with new possibilities]

- Fosfomycin is a broad-spectrum antibiotic agent used orally for uncomplicated cystitis. The intravenous form of administration has recently been authorised in the Netherlands.- Thanks to its broad spectrum and extensive tissue penetration, fosfomycin offers possibilities for the treatment of infections in different organs.- Infections with multidrug-resistant bacteria pose a significant threat to public health. Many of these multidrug-resistant bacteria are sensitive to fosfomycin, which means fosfomycin may be an option for the treatment of infections with multidrug-resistant bacteria. - There is a lack of knowledge about the pharmacological properties of fosfomycin to establish a good dosing schedule. Knowledge is also lacking about the safety of fosfomycin and the extent of its tolerability in the treatment of different infections. - More research is needed before fosfomycin can be used in the battle against multidrug-resistant bacteria.

Impact of (chemo)radiotherapy on immune cell composition and function in cervical cancer patients

New treatments based on combinations of standard therapeutic modalities and immunotherapy are of potential use, but require a profound understanding of immune modulatory properties of standard therapies. Here, the impact of standard (chemo)radiotherapy on the immune system of cervical cancer patients was evaluated. Thirty patients with cervical cancer were treated with external beam radiation therapy (EBRT), using conventional three-dimensional or intensity modulated radiation therapy without constraints for bone marrow sparing. Serial blood sampling for immunomonitoring was performed before, midway and at 3, 6 and 9 weeks after EBRT to analyze the composition of lymphocyte and myeloid-cell populations, the expression of co-stimulatory molecules, T-cell reactivity and antigen presenting cell (APC) function. Therapy significantly decreased the absolute numbers of circulating leukocytes and lymphocytes. Furthermore, the capacity of the remaining T cells to respond to antigenic or mitogenic stimulation was impaired. During treatment the frequency of both CD4⁺ and CD8⁺ T cells dropped and CD4⁺ T cells displayed an increased expression of programmed cell death-1 (PD-1). In vitro blocking of PD-1 successfully increased T-cell reactivity in all five samples isolated before radiotherapy but was less successful in restoring reactivity in samples isolated at later time points. Moreover, (chemo)radiotherapy was associated with an increase in both circulating monocytes and myeloid-derived suppressor cells (MDSCs) and an impaired capacity of APCs to stimulate allogeneic T cells. T-cell reactivity was slowly restored at 6–9 weeks after cessation of therapy. We conclude that conventional (chemo)radiotherapy profoundly suppresses the immune system in cervical cancer patients, and may restrict its combination with immunotherapy.

Evidence of NI-0101 pharmacological activity, an anti-TLR4 antibody, in a randomized phase I dose escalation study in healthy volunteers receiving LPS

Toll-like receptor-4 (TLR4) pathways are major contributors to pathological inflammatory responses induced by tissue damage. NI-0101 is the first monoclonal antibody (mAb) blocking TLR4 signaling. This activity is independent of the ligand type and concentration, therefore, potentially blocking any TLR4 ligands. A phase I single ascending dose study was conducted in 73 healthy volunteers to evaluate NI-0101 tolerability, preliminary safety, pharmacokinetics (PKs), and pharmacodynamics (PDs), in absence and in presence of a systemic challenge with lipopolysaccharide (LPS), a TLR4 ligand. NI-0101 was well tolerated without safety concern. The PK profile was characterized by a half-life of ∼10 days at high concentrations and by a rapid elimination at low concentrations due to expected target-mediated drug disposition. NI-0101 prevented cytokine release following ex vivo and in vivo LPS administration and prevented the C-reactive protein (CRP) increase and the occurrence of flu-like symptoms expected following the in vivo administration of LPS.

Use of population approach non-linear mixed effects models in the evaluation of biosimilarity of monoclonal antibodies

PURPOSE

Population pharmacokinetic analyses (PPK) have been used to establish bioequivalence for small molecules and some biologicals. We investigated whether PPK could also be useful in biosimilarity testing for monoclonal antibodies (MAbs).

METHODS

Data from a biosimilarity trial with two trastuzumab products were used to build population pharmacokinetic models. First, a combined model was developed and similarity between test and reference product was evaluated by performing a covariate analysis with trastuzumab drug product (test or reference) on all model parameters. Next, two separate models were developed, one for each drug product. The model structure and parameters were compared and evaluated for differences.

RESULTS

Drug product could not be identified as statistically significant covariate on any parameter in the combined model, and the addition of drug product as covariate did not improve the model fit. A similar structural model described both the test and reference data best. Only minor differences were found between the estimated parameters from these separate models.

CONCLUSIONS

PPK can also be used to support a biosimilarity claim for a MAb. However, in contrast to the standard non-compartmental analysis, there is less experience with a PPK approach. Here, we describe two methods of how PPK can be incorporated in biosimilarity testing for complex therapeutics.

Levofloxacin-Induced QTc Prolongation Depends on the Time of Drug Administration

Understanding the factors influencing a drug's potential to prolong the QTc interval on an electrocardiogram is essential for the correct evaluation of its safety profile. To explore the effect of dosing time on drug‐induced QTc prolongation, a randomized, crossover, clinical trial was conducted in which 12 healthy male subjects received levofloxacin at 02:00, 06:00, 10:00, 14:00, 18:00, and 22:00. Using a pharmacokinetic‐pharmacodynamic (PK‐PD) modeling approach to account for variations in PKs, heart rate, and daily variation in baseline QT, we find that the concentration‐QT relationship shows a 24‐hour sinusoidal rhythm. Simulations show that the extent of levofloxacin‐induced QT prolongation depends on dosing time, with the largest effect at 14:00 (1.73 (95% prediction interval: 1.56–1.90) ms per mg/L) and the smallest effect at 06:00 (−0.04 (−0.19 to 0.12) ms per mg/L). These results suggest that a 24‐hour variation in the concentration‐QT relationship could be a potentially confounding factor in the assessment of drug‐induced QTc prolongation.

A single infusion of MDCO-216 (ApoA-1 Milano/POPC) increases ABCA1-mediated cholesterol efflux and pre-beta 1 HDL in healthy volunteers and patients with stable coronary artery disease

AIMS

Apolipoprotein A-1 (ApoA-1), based on epidemiology, is inversely associated with cardiovascular (CV) events. Human carriers of the ApoA-1 Milano variant have a reduced incidence of CV disease. Regression of atherosclerotic plaque burden was previously observed on intravascular ultrasound (IVUS) with ETC-216, a predecessor of MDCO-216. MDCO-216, a complex of dimeric ApoA-1 Milano and 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine, is being developed to reduce atherosclerotic plaque burden and CV events. We investigated the efficacy and safety of a single infusion of MDCO-216 in healthy volunteers and in patients with coronary artery disease (CAD).

METHODS AND RESULTS

Twenty-four healthy volunteers and 24 patients with documented CAD received a 2-h infusion of MDCO-216 in a randomized, placebo controlled, single ascending dose study. Five cohorts of healthy volunteers and four cohorts of CAD patients received ApoA-1 Milano doses ranging from 5 to 40 mg/kg. Subjects were followed for 30 days. Dose-dependent increases in ApoA-1, phospholipid, and pre-beta 1 HDL and decreases in ApoE were observed. Prominent and sustained increases in triglyceride, and decreases in HDL-C, endogenous ApoA-1 and ApoA-II occurred at doses >20 mg/kg and profound increases in ABCA1-mediated cholesterol efflux were observed. Other lipid and lipoprotein parameters were generally unchanged. MDCO-216 was well tolerated.

CONCLUSIONS

MDCO-216-modulated lipid parameters profoundly increased ABCA1-mediated cholesterol efflux and was well tolerated. These single-dose data support further development of this agent for reducing atherosclerotic disease and subsequent CV events.

Population Pharmacokinetic Model Characterizing 24-Hour Variation in the Pharmacokinetics of Oral and Intravenous Midazolam in Healthy Volunteers

Daily rhythms in physiology may affect the pharmacokinetics of a drug. The aim of this study was to evaluate 24-hour variation in the pharmacokinetics of the CYP3A substrate midazolam. Oral (2 mg) and intravenous (1 mg) midazolam was administered at six timepoints throughout the 24-hour period in 12 healthy volunteers. Oral bioavailability (population mean value [RSE%] of 0.28 (7.1%)) showed 24-hour variation that was best parameterized as a cosine function with an amplitude of 0.04 (17.3%) and a peak at 12:14 in the afternoon. The absorption rate constant was 1.41 (4.7%) times increased after drug administration at 14:00. Clearance (0.38 L/min (4.8%)) showed a minor 24-hour variation with an amplitude of 0.03 (14.8%) L/min and a peak at 18:50. Simulations show that dosing time minimally affects the concentration time profiles after intravenous administration, while concentrations are higher during the day compared to the night after oral dosing, reflecting considerable variation in intestinal processes.

Microdosing of a Carbon-14 Labeled Protein in Healthy Volunteers Accurately Predicts Its Pharmacokinetics at Therapeutic Dosages

Preclinical development of new biological entities (NBEs), such as human protein therapeutics, requires considerable expenditure of time and costs. Poor prediction of pharmacokinetics in humans further reduces net efficiency. In this study, we show for the first time that pharmacokinetic data of NBEs in humans can be successfully obtained early in the drug development process by the use of microdosing in a small group of healthy subjects combined with ultrasensitive accelerator mass spectrometry (AMS). After only minimal preclinical testing, we performed a first-in-human phase 0/phase 1 trial with a human recombinant therapeutic protein (RESCuing Alkaline Phosphatase, human recombinant placental alkaline phosphatase [hRESCAP]) to assess its safety and kinetics. Pharmacokinetic analysis showed dose linearity from microdose (53 μg) [(14) C]-hRESCAP to therapeutic doses (up to 5.3 mg) of the protein in healthy volunteers. This study demonstrates the value of a microdosing approach in a very small cohort for accelerating the clinical development of NBEs.

Changes in bone mineral density in newly diagnosed testicular cancer patients after anticancer treatment

CONTEXT

Patients with germ cell tumors (GCTs) have an excellent prognosis but are at risk for silent fractures. Data on bone mineral density (BMD) after anticancer treatment are scarce.

OBJECTIVE

The objective of the study was BMD monitoring in GCT patients treated with or without chemotherapy.

DESIGN

We prospectively studied 63 newly diagnosed GCT patients with a median age of 33 years (range 16-70 y) within 3 months of unilateral orchidectomy. Twenty-seven patients (42.9%) had no metastases. Thirty-six patients (57.1%) with metastatic disease received combination chemotherapy.

SETTING

This study was conducted at the outpatient clinic of a single academic institution.

INTERVENTIONS

We performed dual-energy X-ray absorptiometry scans and collected blood samples on a yearly basis, before and up to 5 years after anticancer treatment.

MAIN OUTCOME MEASURES

Changes in total hip and lumbar spine BMD, serum concentrations of gonadal hormones, and bone turnover markers were measured.

RESULTS

BMD remained normal in stage I patients. In patients with metastatic disease, a significant decrease in lumbar spine BMD (-1.52%; P = .004) and total hip BMD (-2.05%; P < .0001) was observed 1 year after chemotherapy and remained stable thereafter for up to 5 years. There was no significant relationship between the observed decrease in BMD and gonadal status, vitamin D status, or cumulative dose of cisplatin or (antiemetic) corticosteroids.

CONCLUSIONS

Metastatic GCT survivors demonstrate significant bone loss within the first year after curative combination chemotherapy, with no recovery up to 5 years after anticancer treatment. Whether this bone loss is associated with increased fracture risk and whether this could be prevented by bone modifying treatment remains to be established.

The use of biomarkers in human pharmacology (Phase I) studies

The development of a new medicine is a risky and costly undertaking that requires careful planning. This planning is largely applied to the operational aspects of the development and less so to the scientific objectives and methodology. The drugs that will be developed in the future will increasingly affect pathophysiological pathways that have been largely unexplored. Such drug prototypes cannot be immediately introduced in large clinical trials. The effects of the drug on normal physiology, pathophysiology, and eventually the desired clinical effects will need to be evaluated in a structured approach, based on the definition of drug development as providing answers to important questions by appropriate clinical studies. This review describes the selection process for biomarkers that are fit-for-purpose for the stage of drug development in which they are used. This structured and practical approach is widely applicable and particularly useful for the early stages of innovative drug development.

Characterization of a standardized glucagon challenge test as a pharmacodynamic tool in pharmacological research

The aim of this study was to characterize a glucagon challenge test as a tool in diabetes research by assessing the inter- and intra-individual variability, and investigating the activity of the autonomic nervous system (ANS) during the challenge, as this might have an indirect impact on glucose homeostasis. The study was performed in 24 healthy volunteers separated in 2 groups. The first group of 12 volunteers underwent a 5-h glucagon challenge during a pancreatic clamp procedure with infusion of [6,6-2H2]-glucose infusion in combination with heart rate variability measurements. In the second group, 12 other healthy volunteers underwent two 6-h glucagon challenges separated by 6 weeks, and fat biopsies were taken for analysis of glucagon receptor expression. Serum glucose rose rapidly after glucagon infusion, and reached a plateau at 90 min. The time profiles suggested rapid development of tolerance for glucagon-induced hyperglycemia. During the glucagon challenge intra- and inter-individual variabilities for hepatic glucose production, the rate of disappearance of glucose, and plasma glucose were approximately 10-15% for all variables. Hyperglucagonemia did not affect heart rate variability. Human adipose tissue had a low, but variable, expression of glucagon receptor mRNA. This standardized glucagon challenge test has a good reproducibility with only limited variability over 6 weeks. It is a robust tool to explore in detail the contribution of glucagon in normal and altered glucose homeostasis and can also be used to evaluate the effects of drugs antagonizing glucagon action in humans without confounding changes in ANS tone.

Pharmacokinetics and pharmacodynamics of orally administered clonidine: a model-based approach

BACKGROUND/AIMS

The oral clonidine test is a diagnostic procedure performed in children with suspected growth hormone (GH) deficiency. It is associated with untoward effects, including bradycardia, hypotension and sedation. Serum clonidine levels have not previously been assessed during this test.

METHODS

In 40 children referred for an oral clonidine test, blood samples were drawn for clonidine and GH. Vital statistics and sedation scores were recorded until 210 min post-dose. We explored the relationship between clonidine concentrations and effects such as GH peak and blood pressure.

RESULTS

Of 40 participants, 5 children were GH deficient. Peak clonidine concentrations of 0.846 ± 0.288 ng/ml were reached after 1 h. Serum levels declined slowly, with concentrations of 0.701 ± 0.189 ng/ml 210 min post-dose. A large interindividual variation of serum levels was observed. During the procedure, systolic blood pressure dropped by 12.8%, diastolic blood pressure by 19.7% and heart rate by 8.4%. Moderate sedation levels were observed. Concentration-effect modeling showed that the amount of GH available for secretion as determined by previous bursts was an important factor influencing GH response.

CONCLUSION

Clonidine concentrations during the test were higher than necessary according to model-based predictions. A lower clonidine dose may be sufficient and may produce fewer side effects.

Obesity is associated with an altered autonomic nervous system response to nutrient restriction

OBJECTIVE

Heart rate variability (HRV) reflects the balance of activities of sympathetic and parasympathetic components of the autonomic nervous system. We compared HRV parameters in response to a prolonged fast in obese versus normal weight humans. In addition, the effect of weight-loss was evaluated in obese individuals.

DESIGN

Intervention study.

PATIENTS

The study subjects included 14 nondiabetic obese (12 females/2 males, aged 30 ± 3 years, Body Mass Index (BMI) 35·2 ± 1·2 kg/m(2) ) and 12 lean subjects (10 females/2 males, aged 27 ± 3 years, BMI 23·3 ± 0·5 kg/m(2) ).

MEASUREMENTS

HRV was examined 75 min after standardized breakfast and after a 48-h fast in 14 nondiabetic obese and 12 lean subjects. The postprandial measurement was repeated in 12 obese subjects after weight-loss.

RESULTS

In lean subjects, fasting decreased high-frequency (HF) power by 43% (P < 0·05) and decreased low-frequency (LF) power by 37% (P = 0·1), leaving the LF/HF ratio unchanged (P = 0·7). In the obese group, autonomic nervous system tone shifted to sympathetic dominance as the LF/HF increased from 0·61 to 1·14 (P = 0·03). After an average weight-loss of 13·8 kg in obese subjects, a trend for sympathetic dominance was found; the LF/HF ratio increased by 56% (P = 0·06).

CONCLUSION

Our data show that a 48-h fast leaves autonomic nervous system balance unaltered in lean subjects. In contrast, a 48-h fast, as well as weight-loss, induces sympathetic dominance in obese humans.

Chemotherapy for testicular cancer induces acute alterations in diastolic heart function

BACKGROUND

After treatment with cisplatin-based chemotherapy for testicular cancer (TC), patients have higher prevalence of cardiovascular complications after long-term follow up. Little is known about acute cardiovascular effects of cisplatin-based chemotherapy. The aim of this study was to explore acute effects of chemotherapy on cardiac function in patients treated for TC.

METHODS

Fourteen TC patients (age 34.6 ± 12.3 years) were studied before and 3 months after start with cisplatin-based chemotherapy. Cardiac function was assessed with magnetic resonance imaging. Fasting glucose and insulin levels were measured and insulin sensitivity, reflected by the quantitative insulin sensitivity index (Quicki index), was calculated.

RESULTS

Left ventricular (LV) end-diastolic volume and LV stroke volume (SV) significantly decreased from 192 ± 27 to 175 ± 26 ml (P<0.05) and 109 ± 18 to 95 ± 16 ml (P<0.05), respectively. The ratio of early and atrial filling velocities across the mitral valve, a parameter of diastolic heart function, decreased after chemotherapy from 1.87 ± 0.43 to 1.64 ± 0.45 (P<0.01). Metabolic parameters were unfavourably changed, reflected by a decreased Quicki index, which reduced from 0.39 ± 0.05 to 0.36 ± 0.05 (P<0.05).

CONCLUSION

Chemotherapy for TC induces acute alterations in diastolic heart function, paralleled by unfavourable metabolic changes. Therefore, early after chemotherapy, metabolic treatment may be indicated to possibly reduce long-term cardiovascular complications.