Saxagliptin and metformin XR combination therapy provides glycemic control over 24 hours in patients with T2DM inadequately controlled with metformin

OBJECTIVE

To assess 24-hour glycemic control with saxagliptin compared with placebo as add-on treatment to metformin in patients with type 2 diabetes mellitus (T2DM) and inadequate glycemic control.

RESEARCH DESIGN AND METHODS

This was a 4-week, multicenter, randomized, double-blind, placebo-controlled Phase IIIb trial comparing the antihyperglycemic activity of saxagliptin 5 mg once daily in combination with a stable dose of metformin extended release (XR) vs. placebo in combination with metformin XR in patients with T2DM inadequately controlled (screening glycated hemoglobin [HbA(1c)] 7-10%) with stable doses of metformin immediate release or metformin XR ≥ 1500 mg/day. Ninety-three adult patients were randomized and received treatment. The primary outcome measure was change from baseline to week 4 in 24-hour mean weighted glucose (MWG).

RESULTS

The reduction from baseline in 24-hour MWG was significantly greater for saxagliptin 5 mg + metformin XR (-13.8 mg/dL; -0.77 mmol/L) compared with placebo + metformin XR (3.0 mg/dL; 0.17 mmol/L) (p = 0.0001). At week 4, the mean decrease in plasma glucose was sustained through a 24-hour period in saxagliptin-treated patients. Treatment with saxagliptin 5 mg + metformin XR resulted in significant mean reductions from baseline in 4-hour mean weighted postprandial glucose (PPG), 2-hour PPG, 3-day average mean daily glucose, and fasting plasma glucose levels compared with placebo + metformin XR (p ≤ 0.001). The proportion of adverse events (AEs) was similar in the two treatment groups, with no reported hypoglycemic AEs in saxagliptin-treated patients. The 4-week evaluation period may have been insufficient to evaluate longer term effects on hyperglycemia or to identify additional AEs.

CONCLUSIONS

In patients with T2DM treated with metformin XR, saxagliptin 5 mg orally administered once daily in the evening for 4 weeks effectively lowered plasma glucose concentrations through the 24-hour dosing interval and was well tolerated.

Efficacy and safety of saxagliptin in combination with metformin compared with sitagliptin in combination with metformin in adult patients with type 2 diabetes mellitus

BACKGROUND

Dipeptidyl peptidase-4 inhibitors improve glycaemic control in patients with type 2 diabetes mellitus when used as monotherapy or in combination with other anti-diabetic drugs (metformin, sulphonylurea, or thiazolidinedione). This 18-week, phase 3b, multicentre, double-blind, noninferiority trial compared the efficacy and safety of two dipeptidyl peptidase-4 inhibitors, saxagliptin and sitagliptin, in patients whose glycaemia was inadequately controlled with metformin.

METHODS

Adult type 2 diabetes mellitus patients (N = 801) with glycated haemoglobin (HbA(1c)) 6.5-10% on stable metformin doses (1500-3000 mg/day) were randomized 1 : 1 to add-on 5 mg saxagliptin or 100 mg sitagliptin once daily for 18 weeks. The primary efficacy analysis was a comparison of the change from baseline HbA(1c) at week 18 in per-protocol patients. Noninferiority was concluded if the upper limit of the two-sided 95% confidence interval of the HbA(1c) difference between treatments was < 0.3%.

RESULTS

The adjusted mean changes in HbA(1c) following the addition of saxagliptin or sitagliptin to stable metformin therapy were - 0.52 and - 0.62%, respectively. The between-group difference was 0.09% (95% confidence interval, - 0.01 to 0.20%), demonstrating noninferiority. Both treatments were generally well tolerated; incidence and types of adverse events were comparable between groups. Hypoglycaemic events, mostly mild, were reported in approximately 3% of patients in each treatment group. Body weight declined by a mean of 0.4 kg in both groups.

CONCLUSIONS

Saxagliptin added to metformin therapy was effective in improving glycaemic control in patients with type 2 diabetes mellitus inadequately controlled by metformin alone; saxagliptin plus metformin was noninferior to sitagliptin plus metformin, and was generally well tolerated.

[Preclinical safety investigation of GB-115 dipeptide]

Preclinical safety investigations of newly synthesized dipeptide compound GB-115 (amide N-phenylhexanoyl-glycyl-L-tryptophan), an antagonist of cholecystokinin receptors, were performed. No animals were lost after GB-115 acute oral administration at a maximum dose of 6000 mg/kg in mice and at 3500 mg/kg in rats. GB-115 administered per os during 6 months in rabbits and rats (both males and females) at the doses of 0.1 and 10 mg/kg induced no irreversible pathological changes in organs and systems studied. The tested dipeptide exhibited no allergenic, immunotoxic and mutagenic activity, and did not affect generative function and the antenatal and postnatal development of progeny. GB-115 at a dose of 10 mg/kg produced suppression of the inflammatory reaction to concanavalin A.

Saxagliptin added to a thiazolidinedione improves glycemic control in patients with type 2 diabetes and inadequate control on thiazolidinedione alone

CONTEXT

Due to the natural progression of type 2 diabetes (T2D), most patients require combination therapy to maintain glycemic control.

OBJECTIVE

Our objective was to evaluate efficacy and safety of saxagliptin plus thiazolidinedione (TZD) in patients with T2D and inadequate glycemic control on TZD monotherapy.

DESIGN

The study was a multicenter, randomized, double-blind, placebo (PBO)-controlled phase 3 trial conducted from March 13, 2006, to October 15, 2007.

SETTING

Patients were recruited from 172 outpatient centers.

PATIENTS

Patients with inadequately controlled T2D [glycosylated hemoglobin (HbA(1c)) 7.0-10.5%], 18-77 yr, receiving stable TZD monotherapy (pioglitazone 30 or 45 mg or rosiglitazone 4 or 8 mg) for at least 12 wk before screening were eligible.

INTERVENTIONS

A total of 565 patients were randomized and treated with saxagliptin (2.5 or 5 mg) or PBO, once daily, plus stable TZD dose for 24 wk.

MAIN OUTCOME MEASURES

Primary outcome was change in HbA(1c) from baseline to wk 24. Secondary outcomes were change from baseline to wk 24 in fasting plasma glucose, proportion of patients achieving HbA(1c) less than 7.0%, and postprandial glucose area under the curve.

RESULTS

At 24 wk, saxagliptin (2.5 and 5 mg) plus TZD demonstrated statistically significant adjusted mean decreases vs. PBO in HbA(1c) [-0.66% (P = 0.0007) and -0.94% (P < 0.0001) vs. -0.30%] and fasting plasma glucose [-0.8 mmol/liter (P = 0.0053) and -1 mmol/liter (P = 0.0005) vs. -0.2 mmol/liter]. Proportion of patients achieving HbA(1c) less than 7.0% was greater for saxagliptin (2.5 and 5 mg) plus TZD vs. PBO [42.2% (P = 0.001) and 41.8% (P = 0.0013) vs. 25.6%]. Postprandial glucose area under the curve was significantly reduced [-436 mmol x min/liter (saxagliptin 2.5 mg plus TZD) and -514 mmol x min/liter (saxagliptin 5 mg plus TZD) vs. -149 mmol x min/liter (PBO)]. Saxagliptin was generally well tolerated; adverse event occurrence and reported hypoglycemic events were similar across all groups.

CONCLUSIONS

Saxagliptin added to TZD provided statistically significant improvements in key parameters of glycemic control vs. TZD monotherapy and was generally well tolerated.

Saxagliptin, a dipeptidyl peptidase IV inhibitor for the treatment of type 2 diabetes

Saxagliptin, a dipeptidyl peptidase-IV (DPP-IV) inhibitor, is currently under development by Bristol-Myers Squibb Co, AstraZeneca plc and Otsuka Pharmaceutical Co Ltd for the treatment of type 2 diabetes. The compound has high selectivity for DPP-IV compared with other dipeptidyl peptidases and a duration profile designed for once-daily dosing. DPP-IV inhibitors act by increasing levels of glucagon-like peptide-1, which stimulates insulin secretion. In animal studies, saxagliptin improved glucose clearance and raised insulin levels in rodents. Clinical trials have demonstrated a dose-dependent inhibition of DPP-IV by saxagliptin without serious side effects. Results have demonstrated that treatment with saxagliptin lowers blood glucose levels, with good tolerability and safety. The specific advantages of saxagliptin over other DPP-IV inhibitors may lie in its long-lived, effective and highly specific inhibition of DPP-IV, making once-daily treatment feasible, effective and safe.

Glucose-lowering activity of the dipeptidyl peptidase-4 inhibitor saxagliptin in drug-naive patients with type 2 diabetes

AIM

Enhancing the physiologic actions of the endogenous incretin hormones, glucagon-like peptide-1 and glucose-dependent insulinotropic polypeptide, by inhibiting dipeptidyl peptidase-4 (DPP-4), the enzyme responsible for their degradation, is an emerging treatment for type 2 diabetes mellitus (T2DM). The aim of this study was to evaluate the safety and efficacy of dose ranges of the DPP-4 inhibitor saxagliptin (BMS-477118) in patients with T2DM.

METHODS

In a 12-week, multicentre, randomized, parallel-group, double-blind, placebo-controlled trial conducted at 152 out-patient US study centres, 338 (low-dose cohort) and 85 (high-dose cohort) drug-naive patients with T2DM and inadequate glycaemic control (baseline HbA1c > or =6.8 and < or =9.7%) were randomized. Following a 2-week washout, patients received saxagliptin 2.5, 5, 10, 20 or 40 mg once daily, or placebo, for 12 weeks (low-dose cohort). In a second cohort, patients received saxagliptin 100 mg once daily, or placebo, for 6 weeks (high-dose cohort). The main outcome measure was saxagliptin dose response assessed as change from baseline in HbA1c following double-blind treatment.

RESULTS

In all treatment arms, saxagliptin significantly reduced HbA1c by 0.7-0.9% from an average baseline of 7.9% vs. placebo (0.3% reduction) in the low-dose cohort. Placebo-subtracted HbA1c reductions were 0.45-0.63% (low-dose cohort). Saxagliptin had significant placebo-subtracted reductions in fasting serum glucose (14-25 mg/dl). Postprandial glucose levels at 60 min following a standard liquid meal test were reduced by 24-41 mg/dl vs. placebo. Saxagliptin was weight neutral. Adverse events were similar across treatment groups, including placebo, with a very low incidence of confirmed hypoglycaemia in saxagliptin treatment arms.

CONCLUSIONS

Saxagliptin effectively improved glycaemic control in drug-naive patients with T2DM and was generally safe, with a tolerability profile similar to placebo.

DPP-4 inhibitors and their potential role in the management of type 2 diabetes

The dipeptidyl peptidase 4 (DPP-4) inhibitors enhance the body's own ability to control blood glucose by increasing the active levels of incretin hormones in the body. Their mechanism of action is distinct from any existing class of oral glucose-lowering agents. They control elevated blood glucose by triggering pancreatic insulin secretion, suppressing pancreatic glucagon secretion, and signalling the liver to reduce glucose production. The leading DPP-4 inhibitors have shown clinically significant HbA1c reductions up to 1 year of treatment and offer many potential advantages over existing diabetes therapies including a low risk of hypoglycaemia, no effect on body weight, and the potential, based on animal and in vitro studies, for the regeneration and differentiation of pancreatic beta-cells. They are efficacious as monotherapy and also in combination with commonly prescribed antidiabetic agents and are suitable for once-daily oral dosing. Consequently, many DPP-4 inhibitors such as vildagliptin (Galvus; LAF-237), sitagliptin (Januvia; MK-0431), and saxagliptin (BMS-477118) have advanced into late-stage human clinical trials. Search strategy and selection criteria This review was built on a systematic MEDLINE search for publications on the subject with the key words: DPP-4 inhibitor; vildagliptin (LAF-237); sitagliptin (MK-0431); saxagliptin (BMS-477118); and type 2 diabetes; up to August 2006. Meeting abstracts were also searched, as much of the data currently only exists in abstract form. Take home message for clinician The DPP-4 inhibitors appear to have great potential for the treatment of type 2 diabetes, but time will tell if this will be realized. While they do not lower glucose to a greater extent than existing therapies, they offer many potential advantages, including the ability to achieve sustainable reductions in HbA1c with a well-tolerated agent that has a low risk of hypoglycaemia and no weight gain, and which can be administered as a once-daily oral dose.

Phase I and pharmacokinetic study of Bay 38-3441, a camptothecin glycoconjugate, administered as a 30-minute infusion daily for five days every 3 weeks in patients with advanced solid malignancies

Bay 38-3441 is a camptothecin glycoconjugate which stabilizes the active lactone form of camptothecin and allows selective uptake into tumor cells. We conducted a phase I study of Bay 38-3441 administered as a 30-minute infusion daily for five consecutive days every 21 days. Thirty-one patients were enrolled at 8 dose levels. Most common nonhematologic side effects were diarrhea (29%), vomiting (19%), nausea (19%), lethargy (13%), and abdominal pain (10%). The main hematologic toxicity was prolonged neutropenia. Nine patients had a best response of stable disease with a median duration of 2.7 months (range: 2.3-20.6 months). The study was closed without reaching the maximum tolerated dose (MTD) due to excessive toxicity in a companion trial resulting in termination of development of this agent. Bay 38-3441 was well tolerated in this study with granulocytopenia as the main hematologic toxicity. This study showed that glycoconjugation is a feasible delivery technique for camptothecin.

A phase I clinical and pharmacokinetic study of the camptothecin glycoconjugate, BAY 38-3441, as a daily infusion in patients with advanced solid tumors

BACKGROUND

The aim of this study was to define the maximum tolerated dose (MTD), dose-limiting toxicity (DLT) and pharmacokinetics of the camptothecin glycoconjugate BAY 38-3441, administered as an infusion for 30 min on two separate schedules every 3 weeks.

PATIENTS AND METHODS

A total of 81 patients with advanced solid tumors were treated with BAY 38-3441 either at doses of 20, 40, 67, 100, 140, 210, 315, 470 and 600 mg/m2/day for 1 day every 3 weeks (single-dose schedule), or at doses of 126, 189, 246, 320 and 416 mg/m2/day once daily for three consecutive days every 3 weeks (3-day schedule). Plasma sampling was performed to characterize the pharmacokinetics of BAY 38-3441 and camptothecin with these schedules.

RESULTS

DLTs included renal toxicity, granulocytopenia and thrombocytopenia on the single-day schedule at doses > or = 470 mg/m2/day, and diarrhea and thrombocytopenia on the 3-day schedule at doses > or = 320 mg/m2/day. Other non-DLTs were gastrointestinal, dermatological and hematological. Pharmacokinetics of BAY 38-3441 and camptothecin appear to be dose-dependent, but not linear.

CONCLUSIONS

Renal toxicity was dose-limiting for BAY 38-3441 using 30-min infusions on the single-dose schedule. Dose escalation to 470 mg/m2/day is feasible using a 2-h infusion. However, because of the superior safety profile, we recommend the 3-day schedule for BAY 38-3441 at a dose of 320 mg/m2/day as 30-min infusions for further phase II studies.

Oral administration of the growth hormone secretagogue NN703 in adult patients with growth hormone deficiency

OBJECTIVE

Little is known of the usefulness of GH secretagogues (GHSs) in GH-deficient (GHD) adults. The objective of this study was to determine the number of responders to treatment with NN703 in GHD adults.

DESIGN

A multicentre, randomized, double-blind, and placebo-controlled study.

PATIENTS

Ninety-seven GHD adults were included.

MEASUREMENTS

The GH response before and after 1 week of oral treatment with NN703 (n = 83) or placebo (n = 14) was determined. The first and last dose of NN703 was 3 mg/kg, whereas the dose of NN703 was 1.5 mg/kg/day during the 6 days between the first and last doses. Furthermore, all 97 patients received 1 micro g/kg GH-releasing hormone (GHRH) 3 weeks after the last dose of NN703.

RESULTS

Serum GH peak and area under curve (AUC) values after the first NN703 administration were greater than those after placebo administration (P < 0.05). However, after correction for the lower body mass index (BMI) in the NN703 group, this difference lost statistical significance. After 1 week of therapy, GH peak and AUC values were similar following the final doses of NN703 and placebo. Serum peak and AUC values of other anterior pituitary hormones were similar between the NN703 and placebo groups both after the first and last administration of study drug. Nine of the 83 patients (11%) responded with a serum peak GH concentration >or= 5 micro g/l after the first and/or last NN703 administration, whereas no patient responded after placebo administration. Serum IGF-I was unaffected by 1-week NN703 treatment, whereas serum IGFBP-3 was increased (P < 0.05 vs. placebo) also after correction for BMI. Mean serum peak GH concentration after GHRH administration was 2.1 micro g/l (+/-0.3, SEM), which was higher than that after the first NN703 administration (1.32 +/- 0.3, P < 0.05).

CONCLUSION

NN703 administration was generally well tolerated. Eleven per cent of the GHD adult patients responded with a peak GH response >or= 5 micro g/l after the first and/or last administration of oral NN703. Although a majority of GHD adults will not respond to NN703, the present results suggest that oral NN703 treatment could be useful in some adult patients with moderately severe GHD. These patients may be identified by a test dose of GHS.

Multiple-dose pharmacokinetics of intranasally administered IS-159 in healthy subjects

This study was designed to investigate the multiple-dose pharmacokinetics of a range of intransal doses of IS-159, a serotonin 1B/1D receptor agonist. Intranasal doses of 1, 2, 4 and 6 mg of IS-159 were administered twice at an interval of 4 hours to 17 healthy male and female subjects in a two-way crossover study. Plasma concentrations of IS-159 were determined from blood samples taken at regular intervals up to 24 hours after the first administration during both treatment periods. IS-159 was rapidly absorbed and eliminated with a t(max) of approximately 15 min and a t(1/2) of approximately 1.6 hours. With increasing dose, the exposure increased dose-proportionally, and IS-159 pharmacokinetics appear not to be influenced by gender and food intake. The results showed dose-proportional pharmacokinetics of IS-159 in the dose range tested and a low propensity for drug accumulation.

A clinical study investigating the pharmacokinetic interaction between NN703 (tabimorelin), a potential inhibitor of CYP3A4 activity, and midazolam, a CYP3A4 substrate

OBJECTIVE

NN703 (tabimorelin) is an orally active growth hormone (GH) secretagogue intended for use as an alternative to daily injections of GH. In vitro studies in human liver microsomes have indicated that NN703 is a mechanism-based inhibitor of CYP3A4. The aim of the present study was to investigate in man the effects of NN703 on the pharmacokinetics of midazolam, a substrate of CYP3A4.

METHODS

Seventeen adult male subjects were enrolled in the study, and each received an oral dose of midazolam (7.5 mg) on four occasions: at baseline (day 1), after one dose of NN703 (day 3), after 7 days once daily NN703 treatment (day 9) and after a 7-day washout period (day 16). The pharmacokinetics of midazolam and its main metabolite, alpha-hydroxymidazolam, were investigated.

RESULTS

Following a single dose of NN703 (day 3), the AUC of both midazolam and alpha-hydroxymidazolam increased by 64% and 34%, respectively (P=0.0001 for both). After repeated NN703 dosing (day 9), NN703 levels reached steady state, and midazolam AUC further increased to 93% relative to baseline (P=0.0001), whereas alpha-hydroxymidazolam AUC decreased slightly and was 11% higher than baseline (n.s.). Following the washout period (day 16), midazolam AUC decreased to values lower than those on day 3 and day 9, but still significantly (45%) higher than baseline levels (P=0.0001). The C(max) values of midazolam and alpha-hydroxymidazolam demonstrated a pattern similar to the AUC, but the effect following repeated NN703 dosing was more pronounced. The t(1/2) of midazolam increased from day 1 to day 3 (P=0.0483) but was essentially unchanged at steady state on day 9.

CONCLUSION

This study shows that administration of NN703 and midazolam, a CYP3A4 substrate, leads to a significant increase in exposure of midazolam. This is consistent with NN703 inhibition of CYP3A4 activity.

The local vascular tolerance to an intravenous infusion of a concentrated glutamine solution in ICU patients

BACKGROUND AND AIMS

The beneficial effects of glutamine is well-documented in ICU patients. However, the documentation and control of enteral administration of glutamine is still insufficient. As an adjunct to enteral nutrition, a concentrated dipeptide solution may be given in a central venous line, but administration via a peripheral vein would be preferable. Therefore, we systematically evaluated local vascular tolerance following a concentrated dipeptide infusion in ICU-patients.

METHODS

ICU-patients (n=20) were randomized to receive a 20% alanyl-glutamine infusion of 0.5 g/kg or placebo during 4 h in a peripheral vein on 3 consecutive days. Local tolerance was evaluated clinically, by Maddox score, and ultrasonically before the infusion and on days 1, 4 and 8 after the infusion.

RESULTS

In the study, 56 out of 60 (93%) planned infusions were administered and 157 out of 168 (93%) clinical evaluations were successfully performed. The ultrasonic evaluation revealed that the utilized veins had a diameter of 2.15+/-0.8 mm (range, 1.0--4.4 mm). There were no signs of thrombophlebitis in any single vein.

CONCLUSION

Administration of a glutamine-containing dipeptide concentrate (20%) by peripheral veins is safe in terms of local tolerance, if a strict protocol is adapted for this purpose is used.

Pronounced effect of caprylocaproyl macrogolglycerides on nasal absorption of IS-159, a peptide serotonin 1B/1D-receptor agonist

OBJECTIVES

This double-blind, randomized, two-way crossover study in 12 healthy male subjects investigated the influence of caprylocaproyl macrogolglycerides on the pharmacokinetics of IS-159 (serotonin-carboxylmethyleneoxy-L-tyrosylglycinamide), a peptide serotonin 1B/1D-receptor agonist, after intranasal administration.

METHODS

A dose of 4 mg IS-159 was administered in a volume of 200 microL, once in the presence and once in the absence of 2% caprylocaproyl macrogolglycerides. Plasma concentrations of IS-159 were measured over a period of 12 hours for determination of pharmacokinetic parameters. Systemic and local tolerability were assessed at regular time points, the latter by rhinoscopy and visual analog scales.

RESULTS

Caprylocaproyl macrogolglycerides significantly increased the maximum plasma concentration (from 4.7 +/- 1.7 to 48 +/- 17 ng/mL) and the area under the plasma concentration-time curve (from 12 +/- 4.7 to 56 +/- 22 ng x h/mL) of IS-159. The time to maximum concentration (15 to 20 minutes) and the elimination half-life (2.0 to 2.3 hours) were not different between the two treatments. Rhinoscopic examination revealed no differences between treatments, but in the presence of caprylocaproyl macrogolglycerides subjects reported more local and systemic adverse events and on the visual analog scales greater nasal obstruction and rhinorrhea.

CONCLUSION

2% caprylocaproyl macrogolglyceride markedly increased the absorption of IS-159 through the nasal mucosa and elicited only mild irritant effects.

Results of a randomized study of IM862 nasal solution in the treatment of AIDS-related Kaposi's sarcoma

PURPOSE

Although advances have been made in the treatment of AIDS-related Kaposi's sarcoma (AIDS-KS) with systemic chemotherapy, less toxic therapies are needed. IM862 is a naturally occurring peptide with antiangiogenic properties and was thus studied in patients with AIDS-KS.

PATIENTS AND METHODS

IM862 was given as intranasal drops at a dose of 5 mg. Patients were randomized to two dosing schedules given in repeated cycles until disease progression or unacceptable toxicity: 5 days of therapy followed by 5 days off (n = 18) and every other day dosing (n = 26).

RESULTS

Forty-two male patients and two female patients with a median age of 38 years (range, 22 to 53 years) were accrued. Twenty-one patients (47%) had more than 50 mucocutaneous lesions, 14 (32%) had lymphedema, and none had visceral involvement. Thirty-three patients (75%) had received prior systemic chemotherapy. Twenty-four patients (55%) had CD4(+) lymphocyte count </= 200/mm(3). All but five patients were being treated with concurrent protease inhibitor(s), for a median of 10 months (range, 0 to 24 months). Major responses were documented in 36%, with five complete and 11 partial remissions, occurring after a median of 6 weeks (range, 3 to 26 weeks) and lasting a median of 33+ weeks (range, 12+ to 95+ weeks). Twenty-one patients had stable disease for periods of 7 to 72+ weeks. Adverse effects to IM862 were limited to mild and transient headache, fatigue, tingling, and nausea. No hematologic adverse effects attributed to treatment were reported.

CONCLUSION

IM862 given as intranasal drops is well tolerated and has antitumor activity in patients with AIDS-KS. A randomized double-blinded study to define the activity of IM862 in patients with AIDS-KS is in progress.

Suppression of spermatogenesis in man induced by Nal-Glu gonadotropin releasing hormone antagonist and testosterone enanthate (TE) is maintained by TE alone

GnRH antagonists plus testosterone (T) suppress LH and FSH levels and inhibit spermatogenesis to azoospermia or severe oligozoospermia. High-dose T treatment alone has been shown to be an effective male contraceptive (contraceptive efficacy rate of 1.4 per 100 person yr). Combined GnRH antagonist and T induces azoospermia more rapidly and at a higher incidence than T alone; this combination has therefore been proposed as a prototype male contraceptive. However, because GnRH antagonists are expensive to synthesize and difficult to deliver, it would be desirable to rapidly suppress sperm counts to low levels with GnRH antagonist plus T and maintain azoospermia or severe oligozoospermia with T alone. In this study, 15 healthy men (age 21-41 yr) with normal semen analyses were treated with T enanthate (TE) 100 mg im/week plus 10 mg Nal-Glu GnRH antagonist sc daily for 12 weeks to induce azoospermia or severe oligozoospermia. At 12-16 weeks, 10 of 15 subjects had zero sperm counts, and 14 of 15 had sperm counts less than 3 x 10(6)/mL. The 14 who were suppressed on combined treatment were maintained on TE alone (100 mg/week im) for an additional 20 weeks. Thirteen of 14 subjects in the TE alone phase had sperm counts maintained at less than 3 x 10(6)/mL for 20 weeks. Ten remained persistently azoospermic or had sperm concentration of 0.1 x 10(6)/mL once during maintenance. Mean LH and FSH levels in the subjects were suppressed to 0.4+/-0.2 IU/L and 0.5+/-0.2 IU/L in the induction phase, which was maintained in the maintenance phase. The 1 subject who failed to suppress sperm counts during induction had serum LH and FSH reduced to 0.3 and 0.5 IU/L, respectively. The subject who failed to maintenance had LH and FSH suppressed to 1.0 and 0.2 IU/L, respectively, during the induction phase but these rose to 1.6 and 2.1 IU/L, respectively, during maintenance. Failure to suppress or maintain low sperm counts may be related to incomplete suppression of serum LH and FSH levels. We conclude that sperm counts suppressed with GnRH antagonist plus T can be maintained with relatively low dose TE treatment alone. This concept should be explored further in the development of effective, safe, and affordable hormonal male contraceptives.

Treatment of common ocular allergic disorders; a comparison of lodoxamide and NAAGA

BACKGROUND/AIMS

Lodoxamide tromethamine and N-acetyl-aspartyl glutamic acid (NAAGA) are mast cell stabilisers, both of which have been shown to be effective in the treatment of allergic conjunctivitis. The aim of this study was to compare the two compounds in patients with common ocular allergic disorders.

METHODS

73 patients participated in a double masked, randomised multicentre study. Diagnoses were chronic allergic conjunctivitis, vernal conjunctivitis, seasonal and atopic conjunctivitis. 36 patients were treated with lodoxamide 0.1% and 37 with NAAGA 4.9%, the drops being instilled four times daily for up to 56 days.

RESULTS

The overall opinion of the physicians and the patients was in favour of lodoxamide at day 10 of the study. At this time, 86% of lodoxamide treated and 49% of NAAGA treated patients considered they had improved. The patients' opinion favoured lodoxamide at day 28 and both physicians' and patients' evaluations were in favour of lodoxamide at day 42. Evaluation of signs and symptoms indicated superiority of lodoxamide at days 42 and 56. Both treatments were well tolerated.

CONCLUSION

While both lodoxamide and NAAGA treatments are associated with clinical improvements in patients with allergic conjunctivitis, lodoxamide may have an earlier onset of action.

Acute calcification in alkali-injured rabbit cornea treated with synthetic inhibitor of metalloproteinases (SIMP)

PURPOSE

The aim of this study was to evaluate the ultrastructure of acute calcification observed in alkali-injured rabbit corneas treated with synthetic inhibitor of metalloproteinases (SIMP).

METHODS

A 12-mm alkali burn was made on the right corneas of 16 rabbits. Eight eyes were treated with topical phosphate-buffered SIMP, and eight control eyes were given the buffer only. Six corneas (five in the SIMP group and one in the control group) developed chalky white opacification in the central area of the cornea within 6-30 days. The corneas were excised for the following examinations: (a) light microscopy, (b) energy-dispersive x-ray analysis, (c) electron microscopy, and (d) high-angle x-ray diffraction.

RESULTS

The results confirmed that there was stromal calcification in these corneas, as shown by positive van Kossa staining, needle-shaped calcium crystal aggregates, and increased calcium in the opaque areas of the corneas. Proteoglycans in the corneal stroma of both the SIMP group and the control group significantly decreased after alkali burns. Very few proteoglycan filaments could be identified in the calcified areas of the stroma. X-ray diffraction reflections with a Bragg spacing of 3.44 +/- 0.04 A were observed from all the calcified corneas treated with SIMP. The intermolecular spacings of collagen fibrils in the calcified stroma (1.24 +/- 0.34 nm) were significantly lower than those in the noncalcified stroma (1.64 +/- 0.04 nm) and the control corneas (1.64 +/- 0.02 nm). The results indicate that the collagen molecules within the fibrils of the calcified stroma are packed more closely than normal.

CONCLUSION

The comparison of the x-ray diffraction patterns from the calcified corneas and chicken bone suggests that the calcium deposits in these corneas are in a form similar to those found in bone. The higher rate and more extensive calcification in the SIMP-treated corneas may result from the inhibitory action of SIMP on debris processing, but the mechanism is unknown.

Therapeutic efficacy of L-ornithine-L-aspartate infusions in patients with cirrhosis and hepatic encephalopathy: results of a placebo-controlled, double-blind study

One hundred twenty-six patients with cirrhosis, hyperammonemia (>50 micromol/L), and chronic (persistent) hepatic encephalopathy (HE), which developed spontaneously without the existence of known precipitating factors, were enrolled in a randomized, double-blind, placebo-controlled clinical trial of intravenously administered L-ornithine-L-aspartate (OA). Patients with subclinical (grade 0, West-Haven criteria) hepatic encephalopathy (SHE), characterized by a prolonged number connection test A (NCT-A) time, and manifest HE (grades I and II, West-Haven criteria) were included in the investigation. The trial was planned as a confirmatory clinical trial OA administered in a dose of 20 g/d, as well as placebo, were dissolved in 250 mL of 5% fructose and infused intravenously for a period of 4 hours during 7 consecutive days with a superimposed protein load at the end of the daily treatment period. Primary variables were postprandial venous ammonia and NCT-A performance time measured following OA or placebo infusions to evaluate the net effect of the treatment on the prevention of the protein-induced hyperammonemia, and on parameters such as NCT-A influenced by hyperammonemia. Mental state gradation, portal systemic encephalopathy index (PSEI), and fasting ammonia levels were estimated as additional efficacy parameters. The data presented are based on the total study sample (intent-to-treat analysis), which included 63 patients in the placebo group and 63 patients in the OA group. Of the 126 patients, 114 met all the criteria for inclusion and completed the trial and treatment as outlined in the protocol (treated-per-protocol analysis). During baseline, the placebo and treatment groups were homogeneous with regard to mental states, NCT-A performance time, fasting venous blood ammonia levels, and Child-Pugh criteria. Although a slight improvement occurred in the placebo group, NCT-A performance times (P < .001) and postprandial venous ammonia concentrations in the OA-treated group showed improvements in comparison with placebo. In addition, venous fasting blood ammonia concentration (P < .01), mental state gradation (P < .001), and PSEI (P < .01), which includes the mental state gradation, NCT-A time, and postprandial venous ammonia in this trial, improved to a much higher degree in the OA group than in the placebo group. In subgroups retrospectively classified according to their initial mental state gradation, OA showed differential but uniformly significant efficacies in patients with manifest HE with respect to ammonia-lowering, improvement in NCT times, and mental state gradation. In patients with initial SHE, OA revealed differences between the medications in the psychometric test used. Adverse events consisting of mild gastrointestinal disturbances were observed in 3 of the OA-treated patients (5%). OA infusion appears to be a safe, effective treatment of chronic (persistent) manifest HE in cirrhotic patients. Additional investigations are required to assess the efficacy of OA in patients with SHE, as well as in patients with more severe grades of HE.