Connexin 43: A Target for the Treatment of Inflammation in Secondary Complications of the Kidney and Eye in Diabetes

Of increasing prevalence, diabetes is characterised by elevated blood glucose and chronic inflammation that precedes the onset of multiple secondary complications, including those of the kidney and the eye. As the leading cause of end stage renal disease and blindness in the working population, more than ever is there a demand to develop clinical interventions which can both delay and prevent disease progression. Connexins are membrane bound proteins that can form pores (hemichannels) in the cell membrane. Gated by cellular stress and injury, they open under pathophysiological conditions and in doing so release 'danger signals' including adenosine triphosphate into the extracellular environment. Linked to sterile inflammation via activation of the nod-like receptor protein 3 inflammasome, targeting aberrant hemichannel activity and the release of these danger signals has met with favourable outcomes in multiple models of disease, including secondary complications of diabetes. In this review, we provide a comprehensive update on those studies which document a role for aberrant connexin hemichannel activity in the pathogenesis of both diabetic eye and kidney disease, ahead of evaluating the efficacy of blocking connexin-43 specific hemichannels in these target tissues on tissue health and function.

Danegaptide Prevents TGFβ1-Induced Damage in Human Proximal Tubule Epithelial Cells of the Kidney

Chronic kidney disease (CKD) is a global health problem associated with a number of comorbidities. Recent evidence implicates increased hemichannel-mediated release of adenosine triphosphate (ATP) in the progression of tubulointerstitial fibrosis, the main underlying pathology of CKD. Here, we evaluate the effect of danegaptide on blocking hemichannel-mediated changes in the expression and function of proteins associated with disease progression in tubular epithelial kidney cells. Primary human proximal tubule epithelial cells (hPTECs) were treated with the beta1 isoform of the pro-fibrotic cytokine transforming growth factor (TGFβ1) ± danegaptide. qRT-PCR and immunoblotting confirmed mRNA and protein expression, whilst a cytokine antibody array assessed the expression/secretion of proinflammatory and profibrotic cytokines. Carboxyfluorescein dye uptake and ATP biosensing measured hemichannel activity and ATP release, whilst transepithelial electrical resistance was used to assess paracellular permeability. Danegaptide negated carboxyfluorescein dye uptake and ATP release and protected against protein changes associated with tubular injury. Blocking Cx43-mediated ATP release was paralleled by partial restoration of the expression of cell cycle inhibitors, adherens and tight junction proteins and decreased paracellular permeability. Furthermore, danegaptide inhibited TGFβ1-induced changes in the expression and secretion of key adipokines, cytokines, chemokines, growth factors and interleukins. The data suggest that as a gap junction modulator and hemichannel blocker, danegaptide has potential in the future treatment of CKD.

Glepaglutide, a novel long-acting glucagon-like peptide-2 analogue, for patients with short bowel syndrome: a randomised phase 2 trial

BACKGROUND

Patients with short bowel syndrome might have impaired postprandial endogenous glucagon-like peptide-2 (GLP-2) secretion, which is required for optimal intestinal adaptation. We aimed to assess the therapeutic potential of glepaglutide, a novel long-acting GLP-2 analogue, for reducing faecal output and increasing intestinal absorption in patients with short bowel syndrome.

METHODS

In this single-centre, double-blind, crossover, randomised phase 2 trial, adults (aged ≥18 to ≤90 years) with short bowel syndrome and with a faecal wet weight output of 1500 g/day or more were randomly assigned to receive one of six dose sequences of glepaglutide (10 mg, 1 mg; 10 mg, 0·1 mg; 1 mg, 10 mg; 1 mg, 0·1 mg; 0·1 mg, 10 mg; or 0·1 mg, 1 mg). Patients received daily subcutaneous injections of the first assigned dose of glepaglutide for 3 weeks, followed by a washout period of 4-8 weeks, and then the second dose of glepaglutide for 3 weeks. An unmasked statistician generated the randomisation list, and the trial investigator enrolled patients and assigned them their patient numbers. Trial investigators, patients, and other care providers were masked throughout the trial. The primary endpoint was the absolute change from baseline in faecal wet weight output, measured separately over the two treatment periods. Metabolic balance studies were done before and after each treatment period to assess the primary endpoint. Per-protocol analysis was used to assess the efficacy. Safety analysis was by intention to treat. This trial is registered at ClinicalTrials.gov, number NCT02690025, and has completed.

FINDINGS

Of the 22 patients screened between Feb 5, 2016, and Jan 25, 2017, 18 patients were randomly assigned and treated with glepaglutide; 16 patients completed the trial. Treatment with 1 mg and 10 mg glepaglutide changed the adjusted mean faecal output by -592 g/day (95% CI -913 to -272; p=0·002) and -833 g/day (-1152 to -515; p=0·0002) from baseline, respectively. No changes were observed with 0·1 mg glepaglutide. Of the 18 patients who were randomly assigned to treatment, common treatment-related adverse events were stoma complications (13 [72%] patients), injection site reactions (11 [61%]), peripheral oedema (ten [56%]), nausea and abdominal pain (eight [44%] each), polyuria and fatigue (six [33%] each), abdominal distention, vomiting, and dizziness (five [28%] each); and cough and decreased appetite (four [22%] each). Related or possibly related serious adverse events were reported in two patients in the 0·1 mg dose group and two patients in the 10 mg dose group. These events included abdominal pain, stoma obstruction, catheter-related sepsis, and infection of unknown origin. No patients died during the trial.

INTERPRETATION

Glepaglutide was well tolerated, and was associated with improved intestinal absorption in patients with short bowel syndrome with 1 mg and 10 mg glepaglutide, but not with 0·1 mg glepaglutide. Larger phase 3 clinical trials of longer durations have been initiated to fully assess the safety and efficacy of glepaglutide.

FUNDING

Zealand Pharma.

Low doses of dasiglucagon consistently increase plasma glucose levels from hypoglycaemia and euglycaemia in people with type 1 diabetes mellitus

AIM

To characterize the pharmacokinetic and pharmacodynamic properties of dasiglucagon, a novel, stable and liquid formulated glucagon analogue, during hypoglycaemic and euglycaemic conditions in adult patients with type 1 diabetes mellitus.

RESEARCH DESIGN AND METHODS

In this randomized double-blind trial, 17 patients received four single subcutaneous doses (0.03, 0.08, 0.2 and 0.6 mg) of dasiglucagon (4 mg/mL formulation) under euglycaemic (plasma glucose [PG] 5.6 mmol/L [100 mg/dL]) or hypoglycaemic (PG 3.1-3.7 mmol/L [56-66 mg/dL]) conditions. For comparison, three doses (0.03, 0.08 and 0.2 mg) of a commercial glucagon formulation (Eli Lilly) were investigated at euglycaemia.

RESULTS

Dasiglucagon led to a dose-dependent and rapid increase in PG levels across all doses tested (mean increases 30 minutes post-dosing of 2.2 to 4.4 mmol/L [39-80 mg/dL] from euglycaemia and 1.3 to 5.2 mmol/L [24-94 mg/dL] from hypoglycaemia), which was higher than the rises elicited by similar doses of commercial glucagon (1.7-3.9 mmol/L [30-71 mg/dL]). The median time (range) to an increase in PG of >1.1 mmol/L (20 mg/dL) was <20 (18-19.5) minutes with 0.03 mg dasiglucagon and, with higher doses, the median times ranged from 9 to 15 minutes (commercial glucagon 13-14 minutes). In hypoglycaemia, 0.03 and 0.08 mg dasiglucagon re-established normoglycaemia (PG ≥3.9 mmol/L [70 mg/dL]) within median times of 14 and 10 minutes, respectively. Nausea and vomiting occurred more frequently with dasiglucagon than with commercial glucagon at identical doses which might be attributable to dasiglucagon's higher potency.

CONCLUSION

Dasiglucagon rapidly increased PG at doses of 0.03 to 0.6 mg in a dose-dependent manner and, therefore, is a good candidate for use in dual-hormone artificial pancreas systems.

Danegaptide for primary percutaneous coronary intervention in acute myocardial infarction patients: a phase 2 randomised clinical trial

OBJECTIVES

Reperfusion immediately after reopening of the infarct-related artery in ST-segment elevation myocardial infarction (STEMI) may cause myocardial damage in addition to the ischaemic insult (reperfusion injury). The gap junction modulating peptide danegaptide has in animal models reduced this injury. We evaluated the effect of danegaptide on myocardial salvage in patients with STEMI.

METHODS

In addition to primary percutaneous coronary intervention in STEMI patients with thrombolysis in myocardial infarction flow 0-1, single vessel disease and ischaemia time less than 6 hours, we tested, in a clinical proof-of-concept study, the therapeutic potential of danegaptide at two-dose levels. Primary outcome was myocardial salvage evaluated by cardiac MRI after 3 months.

RESULTS

From November 2013 to August 2015, a total of 585 patients were randomly enrolled in the trial. Imaging criteria were fulfilled for 79 (high dose), 80 (low dose) and 84 (placebo) patients eligible for the per-protocol analysis. Danegaptide did not affect the myocardial salvage index (danegaptide high (63.9±14.9), danegaptide low (65.6±15.6) and control (66.7±11.7), P=0.40), final infarct size (danegaptide high (19.6±11.4 g), danegaptide low (18.6±9.6 g) and control (21.4±15.0 g), P=0.88) or left ventricular ejection fraction (danegaptide high (53.9%±9.5%), danegaptide low (52.7%±10.3%) and control (52.1%±10.9%), P=0.64). There was no difference between groups with regard to clinical outcome.

CONCLUSIONS

Administration of danegaptide to patients with STEMI did not improve myocardial salvage.

TRIAL REGISTRATION NUMBER

NCT01977755; Pre-results.

Pharmacokinetic and Pharmacodynamic Characteristics of Dasiglucagon, a Novel Soluble and Stable Glucagon Analog

OBJECTIVE

Treatment of severe hypoglycemia outside of the hospital setting is limited to glucagon formulations requiring reconstitution before use, which may lead to erroneous or delayed glucagon administration. We compared the pharmacokinetic (PK) and pharmacodynamic (PD) characteristics and safety and tolerability of different doses of dasiglucagon, a novel soluble glucagon analog, with approved pediatric and full doses of GlucaGen in insulin-induced hypoglycemia in patients with type 1 diabetes.

RESEARCH DESIGN AND METHODS

In this single-center, randomized, double-blind trial, 58 patients with type 1 diabetes received single subcutaneous injections of 0.1, 0.3, 0.6, or 1.0 mg dasiglucagon or 0.5 or 1.0 mg GlucaGen in a state of hypoglycemia (blood glucose target 55 mg/dL) induced by an intravenous insulin infusion.

RESULTS

Dasiglucagon demonstrated a dose-dependent and rapid increase in plasma concentrations, reaching a maximum at ∼35 min with a half-life of ∼0.5 h. Dasiglucagon rapidly increased plasma glucose (PG) by ≥20 mg/dL (9-14 min) to PG ≥70 mg/dL (within 6-10 min), similar to GlucaGen, but with a longer-lasting and greater effect on PG. All patients on both treatments reached these end points within 30 min (predefined success criteria). Both treatments were well tolerated. Nausea was the most frequent adverse event, occurring at a similar rate (44-56%).

CONCLUSIONS

Dasiglucagon was well tolerated and showed an early PD response similar to that of GlucaGen at corresponding doses, suggesting comparable clinical effects of the two glucagon formulations. Dasiglucagon has the potential to become an effective and reliable rescue treatment for severe hypoglycemia in a ready-to-use pen.

A phase I study of recombinant human interleukin-21 (rIL-21) in combination with sunitinib in patients with metastatic renal cell carcinoma (RCC)

BACKGROUND

sunitinib induces partial responses in 47% of patients with metastatic renal cell carcinoma (mRCC). However, the achievement of complete responses remains scarce and all patients will eventually develop progressive disease. Recombinant interleukin-21 (rIL-21) is a novel cytokine, which is believed to deliver sustained cellular anti-tumor response and the combination of both agents may work synergistically.

MATERIAL AND METHOD

from July 2007 to July 2008 in this phase I trial nine therapy-naive patients with metastatic RCC in five European centers were enrolled. Patients with either good or intermediate risk according to Memorial Sloan-Kettering Cancer Center (MSKCC) were eligible without restrictions to histology subtype nor measurable disease. Patients were treated with increasing doses of rIL-21 administered subcutaneously (s.c.) in combination with sunitinib 50 mg once daily (OD) orally at the '4 weeks on/2 weeks off' schedule. Dose-escalation was applied by a conventional '3+3 design'. Planned dose levels (DL) for rIL-21 were 3, 10, 30 and 100 microg/kg s.c. The primary endpoint was to determine the maximum tolerated dose (MTD) and recommended dose (rd). secondary objectives included pharmacokinetics of sunitinib and ril-21, and the induction of ril-21 antibodies.

RESULTS

at 10 microg/kg two dose-limiting toxicities (DLT) occurred in four patients, consisting of grade 4 neutropenia and grade 3 thrombocytopenia. The MTD was 3 microg/kg rIL-21 combined with sunitinib 50 mg OD at the '4 weeks on/2 weeks off' schedule. Frequent occurring adverse events were injection site reaction, stomatitis, fatigue and dysgeusia.

CONCLUSIONS

the combination of sunitinib 50 mg at the '4 weeks on/2 weeks off' schedule and 10 microg/kg IL-21 was not tolerated due to hematological DLTs. The dose level of 3 microg/kg rIL-21 was considered too low to be therapeutically relevant for further evaluation and therefore the study was discontinued.

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.

Clinical and biological efficacy of recombinant human interleukin-21 in patients with stage IV malignant melanoma without prior treatment: a phase IIa trial

PURPOSE

Human interleukin-21 (IL-21) is a class I cytokine that mediates activation of CD8(+) T cells, natural killer (NK) cells, and other cell types. We report final clinical and biological results of a phase II study of recombinant human IL-21 (rIL-21) in patients with metastatic melanoma.

EXPERIMENTAL DESIGN

Open-label, single-arm, two-stage trial.

ELIGIBILITY CRITERIA

unresectable metastatic melanoma, measurable disease by Response Evaluation Criteria in Solid Tumors, no prior systemic therapy (adjuvant IFN permitted), adequate major organ function, good performance status, no significant autoimmune disease, and life expectancy at least 4 months.

PRIMARY OBJECTIVE

antitumor efficacy (response rate).

SECONDARY OBJECTIVES

safety, blood biomarkers, and generation of anti-rIL-21 antibodies. rIL-21 (30 microg/kg/dose) was administered by intravenous bolus injection in 8-week cycles (5 dosing days followed by 9 days of rest for 6 weeks and then 2 weeks off treatment).

RESULTS

Stage I of the study comprised 14 patients. One confirmed complete response (CR) was observed, and as per protocol, 10 more patients were accrued to stage II (total n = 24: 10 female and 14 male). Best tumor response included one confirmed CR and one confirmed partial response, both with lung metastases. Treatment was overall well tolerated. Biomarker analyses showed increases in serum soluble CD25, frequencies of CD25(+) NK and CD8(+) T cells, and mRNA for IFN-gamma, perforin, and granzyme B in CD8(+) T and NK cells.

CONCLUSIONS

rIL-21 administered at 30 microg/kg/d in 5-day cycles every second week is biologically active and well tolerated in patients with metastatic melanoma. Confirmed responses, including one CR, were observed.

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

3055

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.

[Table: see text]

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.

Suppression of elevated cartilage turnover in postmenopausal women and in ovariectomized rats by estrogen and a selective estrogen-receptor modulator (SERM)

OBJECTIVE

Several observational studies indicate that estrogen deficiency increases the incidence of osteoarthritis in postmenopausal women. To validate this observation, we investigated the effects of ovariectomy (OVX) on cartilage erosion in rats using histology and an established bio-assay of cartilage-specific collagen type II degradation products (CTX-II). Furthermore, we investigated whether estrogen and levormeloxifene, a selective estrogen-receptor modulator (SERM), can prevent the OVX-induced changes in cartilage degradation. The clinical relevance was assessed in postmenopausal women by measuring the changes in CTX-II during 12-month treatment with levormeloxifene versus placebo.

DESIGN

Sixty 6-month-old rats were divided in five groups. One group was subjected to sham and the others to OVX, followed by treatment with vehicle alone, estradiol or 0.2 mg/kg/day or 5 mg/kg/day of levormeloxifene. The rats were treated for 9 weeks with biweekly blood and urine sampling for measurement of bone resorption and cartilage turnover. After study termination, hind knees were removed for histological analysis of erosions. The effect of levormeloxifene in post-menopausal women was assessed by measuring CTX-II in samples from 301 women who were participating in a phase II study of this SERM.

RESULTS

OVX rats showed significant increases in the urinary excretion of CTX-II. After 9 weeks this was manifested as increased surface erosion of knee articular cartilage compared with sham-operated rats. Treatment with estrogen or levormeloxifene prevented the OVX-induced changes. There was a significant correlation between the 4-week changes in CTX-II and cartilage erosion at week 9 (r = 0.64, P < 0.001). In postmenopausal women treated with levormeloxifene, the urinary excretion of CTX-II was decreased by approximately 50% and restored CTX-II levels to the premenopausal range.

CONCLUSIONS

This study is the first to demonstrate that a SERM suppresses cartilage degradation in both rodents and humans, suggesting potential therapeutical benefits in the prevention of destructive joint diseases such as osteoarthritis.

Addition of biphasic insulin aspart 30 to rosiglitazone in type 2 diabetes mellitus that is poorly controlled with glibenclamide monotherapy

BACKGROUND

The incidence of type 2 diabetes mellitus (DM) is rapidly increasing worldwide. Results from large-scale studies show that tight blood glucose (BG) control improves the outcome of patients with type 2 DM.

OBJECTIVE

This trial assessed the short-term efficacy and tolerability of adding a thiazolidinedione (rosiglitazone [ROS]) to existing sulfonylurea (SU) therapy (glibenclamide) compared with switching to combination treatment with a premixed insulin (biphasic insulin aspart 30 [BIAsp 30], a rapid-acting insulin analog) and the thiazolidinedione in a select group of patients with type 2 DM whose metabolic control was inadequate with SU monotherapy.

METHODS

In this 6-week, multicenter, open-label, parallel-group trial, patients with type 2 DM whose BG level was not adequately controlled with glibenclamide monotherapy (glycosylated hemoglobin [HbA1c] 8%-13%) were randomized either to replace glibenclamide with BIAsp 30 (individually titrated dosages starting with 6-8 U BID) plus rosiglitazone (4 mg once daily) (BIAsp 30 + ROS group) or to add rosiglitazone (4 mg once daily) to their pretrial doses of glibenclamide (GLIB + ROS group). Patients measured their BG levels immediately before each of the 3 main meals, 90 minutes after the start of each meal, and at bedtime, and mean BG levels were calculated at weeks 0 (baseline), 1, 2, 4, 6, and at 2-week follow-up (week 8). The primary end point was change in mean daily BG level during treatment. Secondary end points included preprandial, postprandial, and bedtime BG levels, serum fructosamine level HbA, and fasting BG level, which were measured at each study visit. Tolerability was assessed using hematologic and biochemical parameters, vital signs, and physical examination.

RESULTS

Forty-nine patients (32 men, 17 women; mean [SD] age, 59.1 [8.9] years; mean [SD] body mass index, 27.7 [3.7] kg/m2) participated in the study. A significant difference was found between treatments in the change in mean daily BG level from baseline to week 6 (P=0.01). After the 6-week treatment period, change in mean serum fructosamine level was significantly greater for BIAsp 30 + ROS compared with GLIB + ROS (P=0.02). HbA1c decreased in both treatment groups from baseline to study end, but the difference between groups was nonsignificant. The changes in fasting BG from baseline to study end also were nonsignificant between groups. Both combinations were well tolerated.

CONCLUSIONS

This short-term study in patients with type 2 DM whose BG level was poorly controlled with glibenclamide monotherapy suggests that switching to a combination of BIAsp 30 + ROS was efficacious and well tolerated and provided an alternative to adding rosiglitazone to existing glibenclamide treatment. The study also suggests that BIAsp 30 may be associated with greater improvements in short-term metabolic control.

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.

Appendicular lean tissue mass and the prevalence of sarcopenia among healthy women

Studies indicate that deficient skeletal muscle mass or sarcopenia is a major cause of disability and morbidity among the elderly. In part, due to the lack of generally applicable normal values, there is still insufficient epidemiologic data available on the frequency and severity of sarcopenia in health and under various disease-related conditions. The objectives of the present study were to (1) characterize the age- and menopause-related variations in appendicular lean tissue mass (LTM(A)), (2) provide young-normal means and estimate the age-specific prevalence of sarcopenia among healthy women. A total of 754 healthy women were included in the study of cross-sectional design. LTM(A) was estimated by dual-energy x-ray absorptiometry (DEXA). Physical characteristics and menopausal status were also registered. LTM(A) as well as height showed significant negative correlation with age with Pearson's r values of -0.43 and -0.06, respectively (P <.05). Trend of finding lower mean values with advancing age remained even when LTM(A) was adjusted for height(2) (ht(2)). Menopause did not seem to have any influence on LTM(A). Young-normal means were obtained from 216 premenopausal women aged 18 to 39 years. Prevalence rates of sarcopenia in healthy women were determined with reference to a cut-off line corresponding to LTM(A) or LTM(A)/ht(2) less than young-normal mean 2 SD and were found to be 40.2% and 12.3%, respectively, among the healthy elderly (>70 years of age). Results of the present study provide further evidence that sarcopenia exists even among otherwise healthy women with increasing age-specific prevalence. Further studies are needed (1) to estimate the prevalence of sarcopenia under various health and disease-related conditions with reference to the hereby given cut-off values and (2) to find therapeutic strategies with beneficial effects in conserving skeletal muscle mass.