Safety, Tolerability, and Pharmacokinetics of High-Volume Subcutaneous Crenezumab, With and Without Recombinant Human Hyaluronidase in Healthy Volunteers

Compared with intravenous formulations, subcutaneous (s.c.) formulations of therapeutic monoclonal antibodies may provide increased patient access and more convenient administration options, although historically high-volume s.c. administration (> 10-15 mL) has been challenging. We report results from two phase I studies in healthy participants (GP29523 and GP40201) that evaluated s.c. crenezumab, an anti-Aβ monoclonal antibody in development for individuals at risk for autosomal-dominant Alzheimer's disease. GP29523 assessed safety, tolerability, and pharmacokinetics (PK) in 68 participants (aged 50-80 years) who received single ascending doses (600-7,200 mg) of crenezumab or placebo (4-40 mL). GP40201 assessed safety, tolerability, and PK in 72 participants (aged 18-80 years) who received different combinations of dose (1,700-6,800 mg), infusion volume (10-40 mL), and flow rate (2-4 mL/minute), with/without recombinant human hyaluronidase (rHuPH20). There were no serious or dose-limiting adverse events in either study. There were no meaningful differences in pain scores among reference placebo (4 mL), test placebo (4-40 mL), or crenezumab (600-7,200 mg) in GP29523, or across treatments with varying infusion volume, flow rate, dose, or rHuPH20 co-administration or concentration in GP40201. Transient erythema was the most common infusion site reaction in both studies. In GP40201 at volumes of ≥ 20 mL, rHuPH20 co-administration appeared to reduce infusion site swelling incidence, but, in some cases, was associated with larger areas of infusion site erythema. Crenezumab exhibited approximately dose-proportional PK, and s.c. bioavailability was 66% and independent of dose or rHuPH20 co-administration. High-dose, high-concentration, high-volume s.c. crenezumab formulated with/without rHuPH20 was well-tolerated in healthy participants, with an acceptable safety profile.

Impaired cardiac autonomic function in women with prior gestational diabetes mellitus

BACKGROUND

Cardiac autonomic neuropathy is a common dysfunction in manifest diabetes mellitus and is associated with duration of diabetes and/or an inadequate glycaemic control. Heart rate variability (HRV) reflects autonomic heart function. The aim of the present study was to investigate whether in women with prior gestational diabetes (GD; pre-type 2 diabetes) alterations of cardiac autonomic function can be observed after delivery in relation to insulin sensitivity and glycaemic control.

MATERIALS AND METHODS

Forty-eight healthy women with prior GD were consecutively admitted to the study. HRV was analysed by both time, as well as frequency, domain methods using 24-h Holter monitoring. In addition, 20 women with normal glucose tolerance during and after pregnancy were investigated as control subjects. All women underwent a frequently sampled intravenous glucose tolerance test (FSIGT) for measurement of insulin sensitivity.

RESULTS

Time domain analysis (standard deviation of normal RR intervals; SDNN) showed a reduced HRV in 25 out of the 48 (52%) women with prior GD. Frequency domain analysis revealed that in these 25 subjects both low and high frequency components of power spectral density (reflecting mainly sympathetic respectively parasympathetic activity) were reduced, indicating that sympathetic as well as parasympathetic functional impairment may be assumed. However, a relative predominance of the sympathetic over parasympathetic cardiac function was observed. The impairment of cardiac autonomic function (reduced SDNN) was correlated with HbA1c values and the 2-h blood glucose concentration (oral glucose tolerance test) but not with insulin sensitivity.

CONCLUSION

The present results demonstrate that in 52% of the women examined who had prior GD, an impairment of cardiac sympathetic as well as parasympathetic function was present, which related to glycaemic control, but not to insulin sensitivity. This infers that functional autonomic changes could be an early prognostic indicator in pre-type 2 diabetes.

Prévention de la carence en vitamine D chez l’enfant et l’adolescent. II. Validation d’un abaque décisionnel non invasif prenant en compte l’exposition solaire et les apports exogènes de vitamine D

OBJECTIVES

Rickets can still be observed among children and adolescents living in Europe, and a significant proportion of healthy children and adolescents presents serum 25-hydroxyvitamin D (25-(OH)D) values below the threshold indicating an insufficient vitamin D status. We have previously proposed detecting at risk individuals with a decision-making abacus based on questionnaires assessing calcium and vitamin D intakes and vitamin D production via sun exposure.

METHODS

We tested the validity of this detection by receiver operating characteristic (ROC) analysis, using, as the main outcome measure, the serum 25-(OH)D values measured at the time of questionnaires presentation. In addition, the original questionnaires have been simplified by limiting the items to those significantly associated with 25-(OH)D values. The study group included 116 children and adolescents aged 6 to 17 years, seen at the end of the winter, and randomized in 2 groups: "test", for the development of the tool (n =75), and "validation" (n =41).

RESULTS

The present analysis shows that the proposed decision-making abacus has a sufficient ability to detect children at risk of vitamin D deficiency (with 25-(OH)D values below 10 ng/ml): area under the curve 0.748/0.895, sensibility 0.71/0.83, and specificity 0.62/0.80, in the test and validation groups, respectively.

CONCLUSION

These questionnaire and abacus may offer a substantial help to detect children and adolescents at risk of vitamin D deficiency in both a private office or hospital environment.

Relative hypoleptinemia in patients with type 1 and type 2 diabetes mellitus

OBJECTIVE

To determine the relation between plasma leptin concentrations and metabolic control in human diabetes mellitus.

DESIGN AND SUBJECTS

Cross sectional study consisting of 156 patients with diabetes mellitus type 1 (n=42), type 2 (n=114), and non-diabetic subjects (n=74).

RESULTS

Plasma leptin concentrations were lower (P<0.05) in type 1 (8.3+/-1.7 ng/ml) and type 2 diabetic (14.9+/-1.8 ng/ml) than in non-diabetic humans (18.3+/-1.9 ng/ml). Only female type 1 and type 2 diabetic subjects also had decreased leptin/BMI ratios (P<0.05 vs non-diabetic females). The log rank test identified age-adjusted correlation of plasma leptin concentration with sex (P<0.0004) and body mass index (P<0.0218), but not with glycosylated haemoglobin A1c (P>0.5) in all groups. Plasma leptin was correlated with age (P<0.0058) and serum triglycerides (P<0.0199) in type 1 diabetic patients, and with serum cholesterol (P<0.0059) and LDL (P<0.0013) in type 2 diabetic patients.

CONCLUSIONS

Defective leptin production and/or secretion might be present independently of metabolic control in female patients with type 1 or type 2 diabetes mellitus.

Elevation of plasma leptin concentrations in obese hyperinsulinaemic hypothyroidism before and after treatment

BACKGROUND

Plasma leptin is considered to play a role in maintenance of energy balance and body weight by neuroendocrine mechanisms. Thyroid hormones are permissive for adrenergic activation, which in turn has been shown to decrease leptin expression. This study was therefore designed to test the hypothesis that hyperthyroidism results in lower leptin concentrations, whereas hypothyroidism leads to higher plasma leptin concentrations. In addition, the effects of normalization of thyroid function on plasma leptin were investigated.

MATERIALS AND METHODS

Fasting plasma leptin concentrations and body fat mass (total body electrical conductivity) were measured in patients with overt hypothyroidism and hyperthyroidism before and after successful treatment. Plasma leptin, glucose, insulin and free fatty acid concentrations were monitored during an oral glucose tolerance test (OGTT 75 g).

RESULTS

Fasting plasma leptin concentrations were similar in lean patients, independently of their thyroid function (hyperthyroid 12.5 +/- 2 ng mL-1, hypothyroid 10.2 +/- ng mL-1, euthyroid 12.7 +/- 3 ng mL-1). In obese hypothyroid patients, plasma leptin was threefold higher (P < 0.0005) than in lean hypothyroid patients, twofold higher (P < 0.005) than in obese hyperthyroid patients matched for fat mass and 30% increased (P < 0.01) compared with obese euthyroid subjects. There were no differences between fasting and post-prandial (OGTT) leptin concentrations in any group. Normalization of thyroid function did not affect plasma leptin, which remained elevated (P < 0.005) in formerly obese hypothyroid patients. Plasma leptin was not associated with serum thyroid hormones but highly correlated with body mass index and body fat mass in all patients (r = 0.85, P < 0.001). Plasma leptin correlated with plasma insulin concentration only in hyperthyroid patients (P < 0.01, r = 0.64), who presented with blunted stimulation of insulin release and higher plasma glucose (P < 0.05) than hypothyroid subjects.

CONCLUSION

The results indicate that (a) the correlation of leptin with body fat mass is preserved in thyroid dysfunction, (b) plasma leptin is markedly increased in obese hypothyroid hyperinsulinaemic patients and (c) plasma leptin is not affected by oral glucose loading.

Pre-school assessment of gifted children

The following paper is an analysis of 27 consecutive referrals of children, thirteen boys and fourteen girls, in one health district, for assessment on the grounds of possible giftedness, with a view to early placement in a state-maintained school or nursery school. The assessments were made using the Ruth Griffiths scales of mental development.