Formulation of Saxagliptin Oral Films: Optimization, Physicochemical Characterization, In-Vivo Assessment, and In-Vitro Real-Time Release Monitoring via a Novel Polyaniline Nanoparticles-Based Solid-Contact Screen Printed Ion-Selective Electrode.

Oral dispersible films have received broad interest due to fast drug absorption and no first-path metabolism, leading to high bioavailability and better patient compliance. Saxagliptin (SXG) is an antidiabetic drug that undergoes first-path metabolism, resulting in a less active metabolite, so the development of SXG oral dispersible films (SXG-ODFs) improves SXG bioavailability. The formula optimisation included a response surface experimental design and the impact of three formulation factors, the type and concentration of polymer and plasticiser concentration on in-vitro disintegration time and folding endurance. Two optimised SXG-ODFs prepared using either polyvinyl alcohol (PVA) or hydroxypropyl methylcellulose were investigated. SXG-ODFs prepared with PVA demonstrated a superior rapid disintegration time, ranging from 17 to 890 s, with the fastest disintegration time recorded at 17 s. These short durations can be attributed to the hydrophilic nature of PVA, facilitating rapid hydration and disintegration upon contact with saliva. Additionally, PVA-based films displayed remarkable folding endurance, surpassing 200 folds without rupture, indicating flexibility and stability. The high tensile strength of PVA-based films further underscores their robust mechanical properties, with tensile strength values reaching up to 4.53 MPa. SXG exhibits a UV absorption wavelength of around 212 nm, posing challenges for traditional quantitative spectrophotometric analysis, so a polyaniline nanoparticles-based solid-contact screen-printed ion-selective electrode (SP-ISE) was employed for the determination of SXG release profile effectively in comparison to HPLC. SP-ISE showed a better real-time release profile of SXG-ODFs, and the optimised formula showed lower blood glucose levels than commercial tablets.

Cost-Effectiveness of Dipeptidylpeptidase-4 Inhibitors Added to Metformin in Patients With Type 2 Diabetes in China.

Purpose: Dipeptidylpeptidase-4 (DPP-4) inhibitors, including linagliptin, alogliptin, saxagliptin, sitagliptin, and vildagliptin, are used for the treatment of type 2 diabetes mellitus (T2DM) patients in China. This study assessed the economic outcomes of different DPP-4 inhibitors in patients with T2DM inadequately controlled with metformin in the Chinese context. Materials and Methods: In this study, the validated Chinese Outcomes Model for T2DM (COMT) was conducted to project economic outcomes from the perspective of Chinese healthcare service providers. Efficacy and safety, medical expenditure, and utility data were derived from the literature, which were assigned to model variables. The primary outputs of the model included the lifetime costs, quality-adjusted life years (QALYs), and incremental cost-effectiveness ratio (ICER). One-way and probability sensitivity analysis was conducted to assess the potential uncertainties of parameters. Results: Of the five competing strategies, alogliptin 25 mg strategy yielded the most significant health outcome, which associated with improvements in discounted QALY of 0.007, 0.014, 0.011, and 0.022 versus linagliptin 5 mg, saxagliptin 5 mg, sitagliptin 100 mg and vildagliptin50 mg, respectively. The sitagliptin 100 mg strategy was the cheapest option. The ICER of alogliptin 25 mg against sitagliptin 100 mg strategy was $6,952 per additional QALY gained, and the rest of the strategies were dominated or extended dominated. The most influential parameters were the cost of DPP-4 inhibitors and their treatment efficacy. Conclusions: These results suggested that alogliptin was a preferred treatment option compared with other DPP-4 inhibitors for Chinese patients whose T2DM are inadequately controlled on metformin monotherapy.

Preclinical Assessment Addressing Intravenous Administration of a [68Ga]Ga-PSMA-617 Microemulsion: Acute In Vivo Toxicity, Tolerability, PET Imaging, and Biodistribution.

It has been herein presented that a microemulsion, known to be an effective and safe drug delivery system following intravenous administration, can be loaded with traces of [68Ga]Ga-PSMA-617 without losing its properties or causing toxicity. Following tolerated IV injections the capability of the microemulsion in altering [68Ga]Ga-PSMA-617 distribution was presented at 120 min post injection based on its ex vivo biodistribution results.

ENZA-p trial protocol: a randomized phase II trial using prostate-specific membrane antigen as a therapeutic target and prognostic indicator in men with metastatic castration-resistant prostate cancer treated with enzalutamide (ANZUP 1901).

OBJECTIVES: To determine the activity and safety of lutetium-177 (177 Lu)-prostate-specific membrane antigen (PSMA)-617 in men with metastatic castration-resistant prostate cancer (mCRPC) commencing enzalutamide, who are at high risk of early progression, and to identify potential prognostic and predictive biomarkers from imaging, blood and tissue. PARTICIPANTS AND METHODS: ENZA-p (ANZUP 1901) is an open-label, randomized, two-arm, multicentre, phase 2 trial. Participants are randomly assigned (1:1) to treatment with enzalutamide 160 mg daily alone or enzalutamide plus 177 Lu-PSMA-617 7.5 GBq on Days 15 and 57. Two additional 177 Lu-PSMA-617 doses are allowed, informed by Day-92 Gallium-68 (68 Ga)-PSMA positron emission tomography (PET; up to four doses in total). The primary endpoint is prostate-specific antigen (PSA) progression-free survival (PFS). Other major endpoints include radiological PFS, PSA response rate, overall survival, health-related quality of life, adverse events and cost-effectiveness. Key eligibility criteria include: biochemical and/or clinical progression; 68 Ga-PSMA PET-avid disease; no prior androgen signalling inhibitor, excepting abiraterone; no prior chemotherapy for mCRPC; and ≥2 high-risk features for early enzalutamide failure. Assessments are 4 weekly during study treatment, then 6 weekly until radiographic progression. Response Evaluation Criteria in Solid Tumours (RECIST) are used to assess imaging conducted every 12 weeks, 68 Ga-PSMA PET at baseline, Days 15 and 92, and at progression, and 18 F-fluorine deoxyglucose (18 F-FDG) PET at baseline and progression. Translational samples include blood (and optional biopsies) at baseline, Day 92, and first progression. Correlative studies include identification of prognostic and predictive biomarkers from 68 Ga-PSMA and 18 F-FDG PET/CT, circulating tumour cells and circulating tumour DNA. The trial will enrol 160 participants, providing 80% power with a two-sided type-1 error rate of 5% to detect a hazard ratio of 0.625 assuming a median PSA-PFS of 5 months with enzalutamide alone. RESULTS AND CONCLUSION: The combination of 177 Lu-PSMA-617 and enzalutamide may be synergistic. ENZA-p will determine the safety and efficacy of the combination in addition to developing predictive and prognostic biomarkers to better guide treatment decisions.

[Efficacy of Saxagliptin for Blood Glucose Control in Hemodialysis Patients with Diabetes].

Studies on the drug saxagliptin (marketed in Japan since 2013) suggest favorable efficacy in hemodialysis patients, but included small sample sizes. Noting that some hemodialysis patients at our medical institution had been switched to saxagliptin 2.5 mg from treatment with other dipeptidyl peptidase-4 inhibitors, we decided to evaluate the effects of switching to saxagliptin on blood glucose control in these patients. The study included 11 patients. Before switching drugs, six of the patients used teneligliptin 20 mg and five used linagliptin 5 mg. Mean glycated albumin (GA) from before to 4 months after switching tended to increase in the previous users of teneligliptin 20 mg (18.4±3.0% to 19.5±2.7%) and tended to decrease in the previous users of linagliptin 5 mg (18.8±3.3% to 17.7±1.4%). Lack of a substantial change in GA when the previous users of teneligliptin 20 mg and linagliptin 5 mg were switched to saxagliptin 2.5 mg indicates that these three agents might have comparable antihyperglycemic profiles when used in patients on hemodialysis. Future research following from this pilot study must evaluate the risk of cardiac failure and incidences of adverse events in a larger population, to investigate the long-term efficacy and safety of switching to saxagliptin.

Concordance with prescribing information dosage recommendations for dipeptidyl-peptidase-4 inhibitors among type 2 diabetes mellitus patients with moderate to severe chronic kidney disease.

OBJECTIVE: To estimate the proportion of patients with moderate to severe chronic kidney disease (CKD) whose initial dipeptidyl-peptidase-4 inhibitor (DPP4-i) dosage was concordant with prescribing information (label) recommendations in the United States. METHODS: Adult patients with type 2 diabetes mellitus (T2DM) who initiated a DPP4-i (linagliptin, sitagliptin, saxagliptin) between 1 January 2011 and 30 June 2014 were identified using electronic medical records and administrative claims, with index date being the date of first observed DPP4-i treatment. Patients were required to have chronic kidney disease (CKD) stage 3b, 4 or 5 (estimated Glomerular Filtration Rate [eGFR] value <45 ml/min/1.73 m2) during the 12 month pre-index period. Patients were classified as concordant or not concordant based on whether the first prescribed dose was consistent with label recommendations. Demographics, clinical characteristics, resource use and costs during pre-index were evaluated by DPP4-i concordance status. RESULTS: Of the 492 patients (323 sitagliptin, 57 saxagliptin, 112 linagliptin), 36.2% were prescribed doses that were not concordant with label recommendations (44.9% for sitagliptin, 57.9% for saxagliptin and 0% for linagliptin [which does not require dosage adjustment]). Concordant patients were slightly older (mean age 71 years vs. 68, p = .01) but had similar gender distribution (55% vs. 60% female, p = .31) compared to those who were not concordant. They had lower general health status (Charlson Comorbidity Score 2.6 vs. 2.2, p = .03), and had similar pre-index all-cause total costs ($25,245 vs. $21,972, p = .68) and lower pre-index T2DM-related costs ($1618 vs. $1922, p = .05). CONCLUSIONS: More than a third of DPP4-i patients with CKD stage 3b or higher were prescribed doses not concordant with DPP4-i label dosage recommendations.

Assessment of the Risk of Hospitalization for Heart Failure With Dipeptidyl Peptidase-4 Inhibitors, Saxagliptin, Alogliptin, and Sitagliptin in Patients With Type 2 Diabetes, Using an Alternative Measure to the Hazard Ratio.

BACKGROUND: Saxagliptin statistically significantly increased the risk of hospitalization for heart failure compared with placebo in the clinical trial of SAVOR-TIMI 53. Neither the reason why only saxagliptin among several dipeptidyl peptidase-4 (DPP-4) inhibitors increased the risk, nor the clinical implication of the result has been explained. OBJECTIVE: To evaluate the risk of hospitalization for heart failure associated with DPP-4 inhibitors by using an alternative measure to the hazard ratio. METHODS: We used the difference in restricted mean survival time (RMST) between DPP-4 inhibitors and placebo to evaluate the risk of cardiovascular events, including hospitalization for heart failure associated with DPP-4 inhibitors. Three randomized clinical trials with cardiovascular events as a primary end point-EXAMINE (alogliptin), SAVOR-TIMI 53 (saxagliptin), and TECOS (sitagliptin)-were reevaluated by estimating the RMSTs for the DPP-4 inhibitors and placebo based on the reconstructed individual patient data for each time-to-event outcome from publicly available information. RESULTS: The differences of RMSTs (DPP-4 inhibitors minus placebo) for hospitalization for heart failure were -4 days [-6, -2] in the SAVOR-TIMI 53 (720 days follow-up), -3 days [-9, 3] in the EXAMINE (900 days follow-up), and 1 day [-5, 7] in the TECOS (1440 days follow-up). There were no substantial differences in the risk of other cardiovascular outcomes between DPP-4 inhibitors and placebo. CONCLUSIONS: There are no substantial clinically relevant differences in the risk of cardiovascular events, including hospitalization for heart failure, between 3 of the DPP-4 inhibitors and placebo.

Saxagliptin versus glipizide as add-on therapy to metformin: assessment of hypoglycemia.

OBJECTIVE: To compare characteristics of hypoglycemic episodes in patients with type 2 diabetes receiving saxagliptin or glipizide add-on therapy to metformin. PATIENTS AND METHODS: This was a post hoc analysis of an international, randomized, parallel-group, double-blind, active-controlled, phase 3 trial. The 52-week trial and 52-week extension were conducted from December 2007 to August 2010. Patients aged ≥18 years with glycated hemoglobin (HbA1c) >6.5% to 10.0% receiving stable metformin doses (≥1500 mg/d) were randomized 1:1 to add-on therapy with saxagliptin 5 mg/d or glipizide 5 to 20 mg/d (titrated to optimal effect or highest tolerable dose during the initial 18 weeks). Hypoglycemic episodes were recorded in patient diaries. Confirmed hypoglycemic events were defined as fingerstick glucose ≤50 mg/dL (≤2.8 mmol/L) with associated symptoms. RESULTS: Of 858 patients randomized, 428 received saxagliptin + metformin, and 430 received glipizide + metformin. Saxagliptin was noninferior to glipizide in lowering HbA1c. Hypoglycemia with saxagliptin + metformin and glipizide + metformin was reported by 15 (24 events) and 165 (896 events) patients, respectively, through week 104. The mean (SD) number of hypoglycemic events per patient reporting hypoglycemia was lower with saxagliptin + metformin versus glipizide + metformin through weeks 52 (1.5 [SD 0.88] vs 4.8 [SD 4.9], respectively) and 104 (1.6 [SD 0.99] vs 5.4 [SD 5.8]). Most patients receiving glipizide + metformin with hypoglycemia had multiple events (124/165 patients [75%]). Confirmed hypoglycemia, major events, and severe events occurred only with glipizide + metformin. Time to first hypoglycemic event was shorter with glipizide versus saxagliptin. Limitations of this analysis include its post hoc nature, a high rate of study discontinuation, and exclusion of patients with serious comorbidities and complications. CONCLUSION: Saxagliptin + metformin was associated with fewer patients reporting hypoglycemia and fewer and less severe hypoglycemic events in those experiencing hypoglycemia compared with glipizide + metformin. ClinicalTrials.gov registration number: NCT00575588.

Cost-effectiveness and budget impact of saxagliptine as additional therapy to metformin for the treatment of diabetes mellitus type 2 in the Brazilian private health system.

OBJECTIVES: To compare costs and clinical benefits of three additional therapies to metformin (MF) for patients with diabetes mellitus type 2 (DM2). METHODS: A discrete event simulation model was built to estimate the cost-utility ratio (cost per quality-adjusted life years [QALY]) of saxagliptine as an additional therapy to MF when compared to rosiglitazone or pioglitazone. A budget impact model (BIM) was built to simulate the economic impact of saxagliptine use in the context of the Brazilian private health system. RESULTS: The acquiring medication costs for the hypothetical patient group analyzed in a time frame of three years, were R$ 10,850,185, R$ 14,836,265 and R$ 14,679,099 for saxagliptine, pioglitazone and rosiglitazone, respectively. Saxagliptine showed lower costs and greater effectiveness in both comparisons, with projected savings for the first three years of R$ 3,874 and R$ 3,996, respectively. The BIM estimated cumulative savings of R$ 417,958 with the repayment of saxagliptine in three years from the perspective of a health plan with 1,000,000 covered individuals. CONCLUSION: From the perspective of private paying source, the projection is that adding saxagliptine with MF save costs when compared with the addition of rosiglitazone or pioglitazone in patients with DM2 that have not reached the HbA1c goal with metformin monotherapy. The BIM of including saxagliptine in the reimbursement lists of health plans indicated significant savings on the three-year horizon.

Safety assessment of gamma-glutamylcysteine sodium salt.

γ-Glutamylcysteine (GGC) is a relatively unexplored option for the treatment of chronic glutathione depletion related disorders that involve down regulation of GGC synthetase. High purity GGC (sodium salt) has only recently become available and, given its reactive capacity, required an investigation of its safety profile. In this report, GGC sodium salt was demonstrated to be safe according to Organisation for Economic Cooperation and Development (OECD) toxicology protocols for acute and repeated doses. No mortalities or adverse effects were observed in Wistar rats following the acute oral (gavage) administration of 2000mg sodium GGC /kg body weight. No animal deaths occurred with daily administration (1000mg/kg sodium GGC) over 90days, with a post trial 28day observation period. GGC had no significant effect on feed consumption, body weights, physical appearance, neurological behaviour and urine chemistry. No consistent significant differences between treatment groups were observed in haematological and clinical chemistry parameters. Similarly, no post-mortem necroscopically identified abnormalities could be attributed to GGC. Based on these observations, sodium GGC can be classed as not acutely toxic at 2000mg/kg, with a no-observed-adverse-effect level (NOAEL) of at least 1000mg/kg/day for systemic toxicology from repeated dose oral gavage administration.

Custo-efetividade e impacto orçamentário da saxagliptina como terapia adicional à metformina para o tratamento do diabetes mellitus tipo 2 no sistema de saúde suplementar do Brasil / Cost-effectiveness and budget impact of saxagliptine as additional therapy to metformin for the treatment of diabetes mellitus type 2 in the brazilian private health system

OBJETIVOS: Comparar custos e benefícios clínicos de três terapias adicionais à metformina (MF) para pacientes com diabetes mellitus tipo 2 (DMT2). MÉTODOS: Um modelo de simulação de eventos discretos foi construído para estimar a relação custo-utilidade (custo por QALY) da saxagliptina como uma terapia adicional à MF comparada à rosiglitazona ou pioglitazona. Um modelo de impacto orçamentário (BIM - Budget Impact Model) foi construído para simular o impacto econômico da adoção de saxagliptina no contexto do Sistema Suplementar de Saúde brasileiro. RESULTADOS: O custo de aquisição da medicação para o grupo de pacientes hipotéticos analisados, para o horizonte temporal de três anos, foi de R$ 10.850.185,00, R$ 14.836.265,00 e R$ 14.679.099,00 para saxagliptina, pioglitazona e rosiglitazona, respectivamente. Saxagliptina exibiu menores custos e maior efetividade em ambas as comparações, com economias projetadas para os três primeiros anos de -R$ 3.874,00 e -R$ 3.996,00, respectivamente. O BIM estimou uma economia cumulativa de R$ 417.958,00 com o reembolso da saxagliptina em três anos a partir da perspectiva de uma operadora de plano de saúde com 1 milhão de vidas cobertas. CONCLUSÃO: Da perspectiva da fonte pagadora privada, a projeção é de que o acréscimo de saxagliptina à MF poupe custos quando comparado ao acréscimo de rosiglitazona ou pioglitazona em pacientes com DMT2 que não atingiram a meta de hemoglobina glicada (HbA1c) com metformina em monoterapia. O BIM, para a inclusão de saxagliptina nas listas de reembolso das operadoras de planos de saúde, indicou uma economia significativa para o horizonte de 3 anos.

OBJECTIVES: To compare costs and clinical benefits of three additional therapies to metformin (MF) for patients with diabetes mellitus type 2 (DM2). METHODS: A discrete event simulation model was built to estimate the cost-utility ratio (cost per quality-adjusted life years [QALY]) of saxagliptine as an additional therapy to MF when compared to rosiglitazone or pioglitazone. A budget impact model (BIM) was built to simulate the economic impact of saxagliptine use in the context of the Brazilian private health system. RESULTS: The acquiring medication costs for the hypothetical patient group analyzed in a time frame of three years, were R$ 10,850,185, R$ 14,836,265 and R$ 14,679,099 for saxagliptine, pioglitazone and rosiglitazone, respectively. Saxagliptine showed lower costs and greater effectiveness in both comparisons, with projected savings for the first three years of R$ 3,874 and R$ 3,996, respectively. The BIM estimated cumulative savings of R$ 417,958 with the repayment of saxagliptine in three years from the perspective of a health plan with 1,000,000 covered individuals. CONCLUSION: From the perspective of private paying source, the projection is that adding saxagliptine with MF save costs when compared with the addition of rosiglitazone or pioglitazone in patients with DM2 that have not reached the HbA1c goal with metformin monotherapy. The BIM of including saxagliptine in the reimbursement lists of health plans indicated significant savings on the three-year horizon.

Cost effectiveness of saxagliptin and metformin versus sulfonylurea and metformin in the treatment of type 2 diabetes mellitus in Germany: a Cardiff diabetes model analysis.

BACKGROUND: The lack of adequate glycaemic control for patients with type 2 diabetes mellitus (T2DM), especially with existing second-line therapies, represents an unmet medical need. Of the newer therapies, the incretin-based medicines, such as saxagliptin, look promising to consolidate second-line pharmacotherapy. OBJECTIVE: This study evaluates the long-term economic consequences of saxagliptin versus sulfonylurea (glipizide) as second-line therapy when used in combination with metformin after failure of monotherapy treatment with metformin, in patients with T2DM in Germany. METHODS: A published discrete event simulation model with a fixed-time increment was used to model the effects of different treatment scenarios over a 40-year (life-) time horizon. Disease progression was modelled using evidence from the United Kingdom Prospective Diabetes Study (UKPDS) 68. The treatment sequence matched that of published German guidelines, and efficacy and safety data were derived from published sources. The model assumes that quality-adjusted life-years (QALYs) are affected by complications, hypoglycaemic events and weight change over a lifetime. Costs were specific to the German setting, where sulfonylureas are generic. Costs and effects were discounted annually at 3%. The extended perspective of the national sick funds was adopted, and recommendations from the Institute for Quality and Efficiency in Health Care (IQWiG) were considered. RESULTS: In the base-case analysis, treatment with saxagliptin plus metformin was associated with a lower incidence of both symptomatic and severe hypoglycaemic events, resulting in an incremental benefit of 0.12 QALYs and an incremental cost-effectiveness ratio (ICER) of €13,931 per QALY gained compared with sulfonylurea plus metformin (year of costing 2009). Modest reductions in all macro- and microvascular complications were seen in those receiving saxagliptin plus metformin compared with sulfonylurea plus metformin. Sensitivity analysis showed that treatment-related weight changes, as a risk factor for complications, represent the most influential driver of cost effectiveness. CONCLUSION: The study demonstrated improved outcomes with saxagliptin at a cost that would likely be considered acceptable in the German setting. Furthermore, the findings of the sensitivity analysis suggest that the results are robust to various assumptions concerning input variables and modelling assumptions.

The design and rationale of the saxagliptin assessment of vascular outcomes recorded in patients with diabetes mellitus-thrombolysis in myocardial infarction (SAVOR-TIMI) 53 study.

OBJECTIVES: Saxagliptin, a dipeptidyl peptidase 4 inhibitor, improves glycemic control in patients with type 2 diabetes mellitus (T2DM) by increasing endogenous active, intact glucagon-like peptide 1 and glucose-dependent insulinotropic polypeptide in response to food, which augments insulin secretion and decreases glucagon release. RESEARCH DESIGN AND METHODS: SAVOR-TIMI 53 is a phase 4, randomized, double-blind, placebo-controlled trial conducted in 25 countries that is designed to evaluate the safety and efficacy of saxagliptin during long-term treatment of approximately 16,500 patients with T2DM. Eligible patients who are either treatment naive or on any background antidiabetic treatment (except incretin therapy) with history of established cardiovascular (CV) disease or multiple risk factors are randomized 1:1 to saxagliptin 5 mg QD (2.5 mg in subjects with moderate/severe renal impairment) or matching placebo, stratified by qualifying disease state. The primary end point is the composite of CV death, nonfatal myocardial infarction, or nonfatal ischemic stroke. The trial will continue until approximately 1,040 primary end points accrue, providing 85% power to identify a 17% relative reduction of the primary end point with saxagliptin versus placebo and 98% power to test for noninferiority of saxagliptin versus placebo (reject the upper limit of 95% CI for a hazard ratio <1.3 at a 1-sided α of .025). CONCLUSION: SAVOR-TIMI 53 is testing the hypothesis that treatment with saxagliptin is safe and reduces CV events in high-risk patients with T2DM.

Phase II assessment of talabostat and cisplatin in second-line stage IV melanoma.

BACKGROUND: Metastatic melanoma is an incurable disease with an average survival of less than one year. Talabostat is a novel dipeptidyl peptidase inhibitor with immunostimulatory properties. METHODS: This phase II, open label, single arm study was conducted to evaluate the safety and efficacy of 75-100 mg/m2 cisplatin combined with 300-400 mcg talabostat bid for 6, 21-day cycles. The primary endpoint was overall response. The rate of complete responses, duration of overall objective response, progression-free survival (PFS), and overall survival were the secondary endpoints. RESULTS: Six objective partial responses were recorded in the 74 patients (8.1%) in the intention-to-treat population. Five of these responses involved the 40 evaluable patients (12.5%). Thirty-one percent of patients reported SAEs to the combination of talabostat and cisplatin. CONCLUSION: Acceptable tolerability was observed in the intention-to-treat population and antitumor activity was observed in 12.5% of evaluable patients, which is not greater than historical expectation with cisplatin alone.

Pilot Study: effects of parenteral glutamine dipeptide supplementation on neutrophil functions and prevention of chemotherapy-induced side-effects in acute myeloid leukaemia patients.

The effect of parenteral glutamine dipeptide (Gln) supplementation on neutrophil phagocytosis, superoxide anion generation (SAG), prevention of chemotherapy-induced side-effects and cost-effectiveness was examined in a pilot study of acute myeloid leukaemia (AML) patients receiving chemotherapy. Sixteen AML patients were randomized to receive intravenous supplementation with Gln (30 g/day) or an equivalent quantity (25 g/day) of a standard amino acid mixture (control) on days 1 - 5 of chemotherapy. Complete blood count was evaluated twice a week until hospital discharge, and neutrophil phagocytosis and SAG were measured when absolute neutrophil count reached > 500 /microl. Patients were observed for development of infection, mucositis and diarrhoea. In Gln-treated patients, the percentage of neutrophil phagocytosis and the SAG levels were significantly higher than in control patients (20.5 +/- 6.0% and 18.9 +/- 2.9 nmol/10(6) neutrophils per 10 min, respectively). The Gln-treated patients lost significantly less weight, tended to have shorter in-patient duration and had less severe oral mucositis than controls. This pilot study provides preliminary indication that parenteral Gln supplementation enhances neutrophil phagocytic function, maintains nutritional status and is cost effective. Parenteral Gln may also prevent oral mucositis, although further studies involving more patients need to be undertaken to confirm this and the other results.

Reduction of Abeta levels in the Sprague Dawley rat after oral administration of the functional gamma-secretase inhibitor, DAPT: a novel non-transgenic model for Abeta production inhibitors.

Considerable effort has been made to develop drugs that delay or prevent neurodegeneration. These include inhibitors of Abeta-generating proteases for the treatment of Alzheimer's disease. Testing the amyloid hypothesis in vivo requires molecules that are capable of entering the CNS and that produce a substantial reduction in brain Abeta levels. Plaque-developing APP transgenic mice are currently widely used as an in vivo model of choice as these animals produce readily measurable amounts of human Abeta. They are very useful in the testing of a variety of amyloid-lowering approaches but their use for compound screening is often limited by their cost. Transgenic animals also require extensive, time-consuming breeding programs and can show high inter-animal differences in the expression level of the transgene. Hence, we considered it important to develop and characterize a new and simple non-transgenic animal model for testing Abeta modulation. For this purpose, Wild-type adult Sprague Dawley rats were treated with DAPT, a functional gamma-secretase inhibitor, and the Abeta40 and Abeta42 levels in brain-tissue and body fluids were assessed. We showed that DAPT, given orally, significantly lowered Abeta40 and Abeta42 peptide levels in brain extract, CSF, and the plasma dose- and time-dependently. We can conclude that our data establish the usefulness of the wild-type rat model for testing small-molecule inhibitors of Abeta production.

Cost containment through L-alanyl-L-glutamine supplemented total parenteral nutrition after major abdominal surgery: a prospective randomized double-blind controlled study.

BACKGROUND & AIMS: Glutamine is recognized as a conditionally essential amino acid. Recent studies indicate that glutamine-containing total parenteral nutrition improves nitrogen economy, enhances gastrointestinal and immune functions and shortens hospital stay. METHODS: Thirty-seven patients (19 w and 18 m; age 61. 4+/-10.4 years; BMI 23.7+/-2.8 kg/m(2)) following major abdominal surgery receiving an isonitrogenous isoenergetic TPN with or without alanyl-glutamine supplementation (0.5 g/kg BW/day), were evaluated in a double-blind, randomized, controlled trial over a five-day period by measuring nitrogen balance, selected biochemical parameters and length of hospital stay. RESULTS: Supplemental alanyl-glutamine improved the overall mean (-3.5+/-1.6 vs. -5.5+/-1. 4 g N;P<0.05) and cumulative nitrogen balance (-14.1+/-9.1 vs. -21.7+/-11.4 g N;P<0.05) compared with the isonitrogenous, isoenergetic standard regimen. Alanyl-glutamine normalized plasma glutamine concentration and reduced the length of hospital stay (12.8+/-2.6 vs. 17.5+/-6.4 days;P<0.05). CONCLUSIONS: The results of the study confirm that supplementation with synthetic alanyl-glutamine dipeptide is associated with cost containment due to shortened hospitalization and improved nitrogen economy.

Glutamine dipeptides in clinical nutrition.

Glutamine is a conditional indispensable amino acid during stress. However, limited solubility and instability of glutamine prevent its addition to presently available nutritional preparations. To overcome these drawbacks, we propose the dipeptide concept by which stable and highly soluble synthetic glutamine containing dipeptides are used. The synthetic dipeptides fulfill all chemical/physical properties to be considered as parenteral substrates. Numerous experimental studies show rapid clearance of parenteral supplied glutamine containing dipeptides without accumulation in tissues; the loss via the urine being inconsequential. Differences related to the dipeptide structure are not observed. There is overwhelming evidence existent that a nutritional support with supplemental glutamine dipeptide positively influences nitrogen excretion, immune status, gut integrity, morbidity, rehabilitation and outcome. Consequently, omission of glutamine from conventional TPN and its subsequent administration should be considered as a replacement of a deficiency rather than a supplementation. It might thus be conceivable that the beneficial effects observed with glutamine nutrition are simply a correction of disadvantages produced by an inadequacy of conventional amino acid solutions. The availability of stable glutamine containing preparations will certainly facilitate an adequate amino acid nutrition in routine clinical setting during episodes of stress and malnutrition.