Obesity does not influence the unique pharmacological properties of different biphasic insulin aspart preparations in patients with type 2 diabetes

AIM

To investigate the influence of obesity in type 2 diabetic patients upon pharmacological properties of different biphasic preparations of insulin aspart.

METHODS

A total of 75 type 2 diabetic patients were stratified according to their body mass index (BMI) into 40 non-obese (BMI 23-28 kg/m(2)) and 35 obese (BMI 30-35 kg/m(2)) subjects. The trial was a double-blinded crossover study. In two periods of 4 weeks each the patients received subcutaneous injections of biphasic insulin aspart 50 (BIAsp 50) or biphasic insulin aspart 70 (BIAsp 70) thrice daily in random order. Insulin doses were titrated individually. At the end of each period 24-h serum profiles of insulin aspart, C-peptide and glucose were recorded. The primary endpoint was the area under the curve of serum glucose concentration during 24 h (AUC(Glu)(0-24 h)).

RESULTS

The insulin concentration profiles of BIAsp 50 and 70 were as expected according to the content of protamine-bound insulin aspart (50 and 30% respectively). AUC(Glu(0-24 h)) BIAsp 50/BIAsp 70 ratios were 0.97 (95% CI: 0.90-1.05, p = 0.49) for non-obese and 0.98 (95% CI: 0.92-1.05, p = 0.55) for obese. Fasting serum glucose (FSG) BIAsp 50/BIAsp 70 ratios were 0.90 (95% CI: 0.84-0.96, p = 0.002) for non-obese and 0.90 (95% CI: 0.84-0.97, p = 0.006) for obese. During both treatment regimens the frequency of minor hypoglycaemic episodes was highest for the non-obese group.

CONCLUSIONS

The pharmacokinetic and pharmacodynamic characteristics of the two preparations of biphasic insulin aspart were different; however, they were not influenced by the degree of obesity in type 2 diabetic patients.

Anti-tumor activity of recombinant human Interleukin-21 (rIL-21): Preliminary data from a phase 2a study in patients with stage IV malignant melanoma (MM) without prior treatment

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Background: rIL-21 is a pleiotropic class I cytokine that activates CD8+ T cells and NK cells. The safety and pharmacologic profile of rIL-21 was characterized in two phase 1 dose escalation studies including patients with MM, performed in Australia and the US, respectively. Two dosing schedules were tested: “5+9” (5 days of dosing followed by 9 days of rest) and “3/wk” (dosing 3 times per week for 6 weeks). The maximum tolerated dose (MTD) was determined to be 30 μg/kg for both dosing regimens and two complete remissions (at the 30 μg/kg dose level) were observed in the MM patients. A phase 2a study was initiated to estimate the preliminary efficacy of rIL-21 in patients with advanced MM. Methods: The phase 2a study design is an open-label, two-stage trial. Primary objective: antitumor efficacy as determined by response rate. Secondary objectives: safety, effects on blood biomarkers, and measurement of anti-rIL-21 antibodies. Eligible patients had unresectable MM with measurable disease, no prior systemic therapy (adjuvant interferon was permitted), adequate major organ function, good performance status, no brain metastases, and no evidence of significant autoimmune disease. rIL-21 was administered by i.v. bolus injection using the “5+9” regimen for 6 weeks (= three cycles) at 30 μg/kg dose level. Results: At the time of writing (January 2007), all 14 patients have entered the first stage of the phase 2a study and currently seven patients are evaluable for response after completion of 3 treatment cycles (6 weeks). One patient had a complete remission, five patients had stable disease, and one patient had progressive disease. So far, six patients have gone on to receive further treatment with rIL-21. Similar to the phase 1 experience, treatment with rIL-21demonstrated an acceptable safety profile. Updated interim study results, including response data, will be presented. Conclusions: rIL-21 administered at 30 μg/kg/day using the “5+9” regimen is well tolerated by patients with MM. Preliminary evidence of clinical response has been observed and the second stage of the two-stage phase 2a study has opened for accrual.

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Biphasic insulin aspart given thrice daily is as efficacious as a basal-bolus insulin regimen with four daily injections: a randomised open-label parallel group four months comparison in patients with type 2 diabetes

AIMS

To show that a thrice daily meal-time biphasic insulin aspart (BIAsp) treatment regimen is as efficacious as a 4 times daily basal-bolus regimen with human isophane insulin (NPH) and insulin aspart (IAsp).

METHODS

A multinational, randomised, open-label parallel-group trial in 394 patients with type 2 diabetes on a once or twice daily insulin regimen. Patients were randomised 1:1 to BIAsp or IAsp+NPH for 16 weeks. The BIAsp group was treated according to individual needs using BMI as a surrogate index of insulin resistance. Subjects administered BIAsp 70 (BMI< or =30 kg/m (2)) or BIAsp 50 (BMI>30 kg/m (2)) with breakfast and lunch and BIAsp 30 with dinner. The IAsp+NPH group injected IAsp at meals and NPH at bedtime as basal insulin. HbAlc levels after 16 weeks were compared between treatments using a predefined non-inferiority criterion of 0.4%. The incidence of hypoglycaemic episodes and adverse events was evaluated.

RESULTS

Mean HbAlc (+/-SD) decreased from 9.1+/-0.7% to 7.8+/-1.0% with both treatments. Glycaemic control provided by BIAsp was non-inferior to that obtained by the IAsp+NPH (intention to treat ITT) population: diff, HbAlc -0.05%; 95% CI (-0.24; 0.14); per protocol (PP) population: diff, HbAlc -0.03%; 95% CI (-0.23; 0.16). Similar improvements in glycaemic control in both groups were confirmed by self-measured 8-point plasma glucose (PG) profiles, average and fasting PG concentrations, and average prandial PG increments. The incidence of adverse events and hypoglycaemic episodes was similar in the two treatment groups.

CONCLUSIONS

A thrice daily meal-time BIAsp regimen is a suitable alternative to an intensified insulin regimen in people with inadequately controlled type 2 diabetes mellitus, and requires fewer daily injections than a basal-bolus therapy without compromising efficacy and safety.

Oral ibandronate: changes in markers of bone turnover during adequately dosed continuous and weekly therapy and during different suboptimally dosed treatment regimens

The aims of the present study were to investigate how changes in the cumulative dose and the frequency of dosing influence the short-term antiresorptive efficacy of oral ibandronate treatment and whether serial measurements of bone markers could provide a useful diagnostic tool for the revelation of noncompliance to established treatments with antiresorptive drugs. Study participants were 200 healthy women 50-70 years old (mean 63.1 years) with a lumbar spine BMD t-score of -1 to -5. Women were randomly allocated to receive treatment with oral ibandronate according to one of the following eight dosing regimes: (1) 2.5 mg daily for 84 days; (2) 20 mg weekly for 84 days; (3) 2.5 mg daily for 28 days + no treatment for 56 days; (4) 2.5 mg daily for 28 days + 2.5 mg weekly for 56 days; (5) 2.5 mg daily for 28 days + 2.5 mg three times weekly for 56 days; (6) 2.5 mg daily for 14 days + 2.5 mg three times weekly for 56 days; (7) 2.5 mg three times weekly for 84 days; (8) no treatment for 168 days. Study parameters were the serum concentration of the C-terminal telopeptide of collagen type I (s-CTX, resorption marker) and N-MID osteocalcin (formation marker) measured by enzyme-linked immunosorbent assay. Oral treatment with ibandronate 20 mg weekly (cumulative dose 240 mg) resulted in greater final inhibition in s-CTX and area under the curve (AUC) compared to the 2.5 mg daily treatment (cumulative dose 210 mg), indicating that as long as optimal doses are administered the frequency of dosing has secondary importance for overall efficacy. When the cumulative dose was 130 mg or less, the final degree of inhibition was still the function of the cumulative dose, but the overall efficacy estimated by the AUC was also under the influence of the frequency of dosing. These observations suggest that serial measurements of s-CTX may provide a useful diagnostic tool for the early revelation of suboptimal dosing or noncompliance to already optimized therapies with antiresorptive agents.

Cartilage turnover assessed with a newly developed assay measuring collagen type II degradation products: influence of age, sex, menopause, hormone replacement therapy, and body mass index

BACKGROUND

Cartilage normally has a slow turnover but in arthritis increased metabolism results in degradation of the tissue.

OBJECTIVE

To assess cartilage turnover in a sample of the general population by an assay measuring cartilage derived urinary collagen type II (CTX-II) C-telopeptide degradation products.

METHODS

CTX-II concentrations were measured in urine samples from 615 healthy men and women aged 20-87 years, and the influence of age, sex, menopause, hormone replacement therapy (HRT), and body mass index (BMI) was assessed.

RESULTS

CTX-II concentrations showed age dependent variations, with notable differences between men and women. Mean (SD) CTX-II concentration in postmenopausal women (220 (118) ng/mmol, n=25) was significantly higher than in an age matched group of premenopausal women (112 (79) ng/mmol, n=26, p<0.001). CTX-II concentration in women using HRT (118 (57) ng/mmol, n=50) was significantly lower than in an age and BMI matched group of women not receiving HRT (215 (99) ng/mmol, n=50, p<0.001). In subjects with a BMI >or=25 kg/m(2), CTX-II concentrations were significantly higher than in those with a BMI <25 kg/m(2) (185 (114) v 148 (91) ng/mmol, p<0.001).

CONCLUSIONS

Cartilage turnover, as assessed by measuring urinary degradation products of CTX-II varies considerably with age, and significant differences between CTX-II levels in men and women as well as in pre- and postmenopausal women are found. Further studies are required to validate the marker for assessing cartilage degradation in arthritis.

Effect of bisphosphonates on cartilage turnover assessed with a newly developed assay for collagen type II degradation products

BACKGROUND

Animal studies of arthritis have suggested that bisphosphonates may have chondroprotective abilities.

OBJECTIVE

To evaluate the effect of bisphosphonate treatment on cartilage degradation.

METHODS

Type II collagen is almost exclusively localised in cartilage, where it is the major structural component of the tissue. Hence fragments derived from this protein should represent a specific index for cartilage degradation. The urinary concentration of collagen type II C-telopeptide degradation products (CTX-II) was measured by a new immunoassay (enzyme linked immunosorbent assay (ELISA)). The serum concentration of collagen type I C-telopeptide degradation products (CTX-I), a marker of bone degradation, was also measured by ELISA.

PARTICIPANTS

Two groups were studied. The alendronate group included 63 healthy postmenopausal women aged 45-54 randomly allocated to receive three years' treatment with 1 mg, 5 mg, 10 mg, or 20 mg alendronate daily or placebo. In the third year the women receiving 20 mg were switched to placebo. The ibandronate group included 119 women at least 10 years after the menopause aged <75 randomly allocated to receive 12 months' treatment with 0.25 mg, 0.5 mg, 1.0 mg, 2.5 mg, or 5 mg ibandronate daily or placebo followed by 12 months without treatment.

RESULTS

20 mg of alendronate and 2.5 and 5 mg of ibandronate treatment produced significant decreases in urinary CTX-II to about 50% of baseline. The level reached after three months of treatment remained practically constant during the following 12-36 treatment months. When treatment was withdrawn CTX-II values returned towards baseline. Serum CTX-I also decreased rapidly within three months, but to a level of about 30% of baseline.

CONCLUSIONS

The urinary excretion of CTX-II, a new marker of cartilage degradation, decreases significantly in response to bisphosphonate. This suggests that bisphosphonates may have chondroprotective effects in humans. By measurement of CTX-II it should be possible to monitor the effects of drugs that potentially inhibit cartilage destruction.