Simulated evaluation of a non-Luer safety connector system for use in neuraxial procedures.

BACKGROUND: Spinal syringes, needles, and other devices with connectors that will not also connect with Luer devices could substantially reduce wrong-route drug administration errors. This study aimed to evaluate a newly designed non-Luer safety connector system for neuraxial procedures in terms of clinical acceptability and cross-connectivity with conventional Luer devices. METHODS: A non-Luer safety connector system (BD UniVia-6 Safety Connector system), which included non-Luer spinal needles, syringes, and blunt fill filter needles, was evaluated in a prospective, simulated use, randomized study. Clinicians evaluated the acceptability and performance characteristics using a normal saline injectate on an artificial back model. RESULTS: Forty-nine clinicians participated in the study. For 93 of 98 spinal injection procedures, clinicians agreed that overall, the safety system was clinically acceptable (94.9%; 95% lower bound 89.6%). Forty-eight clinicians (98%; 95% lower bound: 90.7%) agreed that the safety system prevented or reduced the risk of misconnection between a conventional syringe and a safety spinal needle. A lower proportion (63.3%; 95% lower bound: 50.5%) agreed that the safety system would prevent or reduce the risk of misconnections between a safety syringe filled with medication intended for spinal injection and an i.v. Luer device. CONCLUSIONS: Our study demonstrated that study clinicians found the safety system to be acceptable with minimal impact on technique in a simulated-use setting. The non-Luer system also appeared to decrease the risk of administration of i.v. medications into the intrathecal space. Further modifications will be required to completely eliminate the risk of administering intrathecal medication i.v. and evaluation in a clinical setting will help determine the true impact of this non-Luer system on patient safety.

Long-term safety and antihypertensive efficacy of irbesartan: pooled results of five open-label studies.

An analysis of 5 multicenter, open-label studies was conducted to evaluate the long-term safety and efficacy of irbesartan in 1,006 patients with seated diastolic blood pressure (SeDBP) 95-110 mm Hg. Irbesartan monotherapy was started at 75 mg and titrated to 300 mg at 2- to 4-week intervals to achieve normalized blood pressure (SeDBP <90 mm Hg). If normalized BP was not attained with irbesartan 300 mg alone, adjunctive medications could be added. At 12 months of therapy, the mean reduction in seated systolic blood pressure/SeDBP was 21.0/15.8 mm Hg, and 83% (684/821) of patients were normalized. Of those normalized, 64% were receiving irbesartan monotherapy and 86% were receiving irbesartan or irbesartan/hydrochlorothiazide only. No evidence of tachyphylaxis to the antihypertensive effect of irbesartan was noted. Thus, long-term irbesartan therapy, with or without other antihypertensives, achieved and maintained normalized BP in the majority of patients and was well tolerated.

The antihypertensive efficacy of the combination of irbesartan and hydrochlorothiazide assessed by 24-hour ambulatory blood pressure monitoring. Irbesartan Multicenter Study Group.

In a multicenter, double-blind, randomized trial, 178 patients with ambulatory diastolic blood pressure (BP) > or =85 mm Hg and seated diastolic BP (SeDBP) 95-110 mm Hg received either once-daily irbesartan 75 mg/hydrochlorothiazide (HCTZ) 12.5 mg, irbesartan 150 mg/HCTZ 12.5 mg, or placebo for 8 weeks to assess reductions in 24-hour ambulatory BP and office BP. Safety and tolerability of all treatment regimens were also evaluated. BP results and therapeutic response (trough SeDBP normalized to <90 mm Hg) were expressed as change from baseline to Week 8. Mean reductions in 24-hour ambulatory BP and office seated BP for irbesartan/HCTZ combinations were significantly greater compared with placebo (all, p<0.01). More patients were normalized with irbesartan/HCTZ (65%-69%) than placebo (24%, p<0.01). The frequency of adverse events was similar in all groups. Irbesartan/HCTZ given once-daily appears to be a well-tolerated, safe, and effective antihypertensive treatment.

Matrix study of irbesartan with hydrochlorothiazide in mild-to-moderate hypertension.

The purpose of this study was to assess the safety and antihypertensive dose-response effects of irbesartan and hydrochlorothiazide (HCTZ) in patients with mild-to-moderate hypertension. After a 4- to 5-week single-blind placebo lead-in period, 683 patients with seated diastolic blood pressure (SeDBP) between 95 and 110 mm Hg were randomized to receive once-daily dosing with one of 16 different double-blind, fixed combinations of irbesartan (0, 37.5, 100, and 300 mg irbesartan) and HCTZ (0, 6.25, 12.5, and 25 mg HCTZ) for 8 weeks. The primary efficacy variable was the change from baseline in trough SeDBP after 8 weeks of therapy. Data were analyzed by response surface modeling. At Week 8, mean changes from baseline in trough SeDBP (mm Hg) ranged from -3.5 for placebo, -7.1 to -10.2 for the irbesartan monotherapy groups, -5.1 to -8.3 for the HCTZ monotherapy groups, and -8.1 to -15.0 for the combination groups. Irbesartan plus HCTZ produced additive reductions in both SeDBP and seated systolic BP, with at least one combination producing greater BP reduction than either drug alone (P < .001). All treatments were well tolerated; there were no treatment-related serious adverse events. Irbesartan tended to ameliorate the dose-related biochemical abnormalities associated with HCTZ alone. In conclusion, the combination of HCTZ in doses up to 25 mg with irbesartan, in doses up to 300 mg, is safe and produces dose-dependent reductions in BP.

Safety of irbesartan in the treatment of mild to moderate systemic hypertension.

Nine multicenter, randomized, placebo-controlled studies were conducted to evaluate the safety and tolerability of the angiotensin II subtype 1 receptor blocker (AT1 blocker) irbesartan for the treatment of mild to moderate hypertension. After a 4- to 5-week placebo lead-in phase, patients were randomized to 4 to 12 weeks of double-blind therapy with either placebo (n = 641) or irbesartan (n = 1,965) at doses of 1 to 900 mg orally. All doses of irbesartan were well tolerated with no evidence of dose-related adverse effects. Across the full recommended clinical dose range, although not statistically significantly different, irbesartan use was associated with a lower incidence of adverse events, serious adverse events, and discontinuations due to adverse events compared with placebo. No clinically significant or unexpected changes in laboratory analyses were observed. Withdrawal of irbesartan therapy did not result in rebound hypertension or clinically important adverse events. Thus, irbesartan use in hypertensive patients was associated with a placebo-like safety and tolerability profile.

Comparative efficacy of two angiotensin II receptor antagonists, irbesartan and losartan in mild-to-moderate hypertension. Irbesartan/Losartan Study Investigators.

The primary objectives of this double-blind study were to compare the antihypertensive efficacy and tolerability of irbesartan and losartan, two angiotensin II (AT1 subtype) receptor antagonists with different pharmacokinetic profiles in patients with mild-to-moderate hypertension. Both drugs are approved for once-daily use (although losartan may also be prescribed twice-daily). After a placebo lead-in, 567 patients were randomized (1:1:1:1) to once-daily therapy with placebo, 100 mg losartan, 150 mg irbesartan, or 300 mg irbesartan for 8 weeks. Treatment groups had comparable demographic and baseline characteristics. After 8 weeks of treatment, reductions from baseline in trough seated diastolic blood pressure (SeDBP) and trough seated systolic blood pressure (SeSBP) with 300 mg irbesartan were greater than with 100 mg losartan (P < .01 for both comparisons), by 3.0 and 5.1 mm Hg, respectively; larger reductions were also demonstrated at weeks 1 and 4 (P < .01 and P = .017, respectively, for SeDBP). Throughout the study, the antihypertensive effect of 150 mg irbesartan did not differ significantly from that of 100 mg losartan. All therapies were well tolerated. The 300 mg dose of irbesartan was associated with the lowest incidence of adverse events (AE) and discontinuations because of AE. This study demonstrates that the maximally effective once-daily doses of two different AT1 receptor antagonists may result in clinically significant differences in blood pressure reductions, and therefore highlights the potential importance of the pharmacokinetic and pharmacodynamic differences between these two members of this class.

Dose-related antihypertensive effects of irbesartan in patients with mild-to-moderate hypertension.

Two multicenter, double-blind, placebo-controlled, parallel group studies were conducted to evaluate the efficacy, safety, pharmacokinetics, and pharmacodynamics of the angiotensin II receptor (AT1 subtype) antagonist irbesartan. The effect of irbesartan withdrawal and the effect of adding hydrochlorothiazide (HCTZ) to irbesartan were also assessed. After a placebo lead-in phase, all patients were randomized to 8 weeks of double-blind therapy with either placebo (n = 158) or irbesartan at doses of 1, 5, 10, 25, 50, 100, 200, or 300 mg (n = 731 total) orally once daily. Irbesartan reduced blood pressure in a dose-related manner. Reductions from baseline in trough seated diastolic blood pressure ranged from 7.5 mm Hg for 50 mg irbesartan to 11.6 mm Hg for 300 mg irbesartan. At week 8, statistically significant reductions over placebo were observed in trough seated blood pressure with all irbesartan doses > or = 50 mg. These reductions reached statistical significance versus placebo within 2 weeks with 100, 200, and 300 mg irbesartan. Plasma irbesartan concentrations correlated with dose. Angiotensin II and aldosterone levels generally showed dose-related changes, consistent with AT1 receptor blockade. In patients not controlled at 8 weeks, the addition of 12.5 mg HCTZ resulted in further dose-related reductions in blood pressure. Irbesartan demonstrated a placebo-like safety profile and no dose-related toxicity. Irbesartan, administered alone or in combination with HCTZ, was well tolerated. Withdrawal of irbesartan did not result in rebound hypertension or adverse events. Thus, once-daily irbesartan is both an effective and safe antihypertensive agent for the treatment of mild-to-moderate hypertension.

Dose-related efficacy of irbesartan for hypertension: an integrated analysis.

Results of eight multicenter, randomized, placebo-controlled, double-blind, parallel-group studies were pooled to assess the efficacy of the angiotensin II-receptor blocker irbesartan over the dose range of 1 to 900 mg. A total of 2955 adults with a seated diastolic blood pressure of 95 to 110 mm Hg were randomized to treatment with oral irbesartan once daily or placebo for 6 to 8 weeks. Office blood pressure was measured at trough (24+/-3 hours after the last dose) and peak (3+/-1 hours after the last dose) by mercury sphygmomanometry. Demographic characteristics (mean blood pressure; 151/101 mm Hg; mean age, 54 years; 63% male; and 82% white) were similar across all dose groups. After the groups were pooled, antihypertensive efficacy was assessed by therapeutic response (trough seated diastolic blood pressure <90 mm Hg or a reduction from baseline of > or = 10 mm Hg) and by modeling of the maximum reductions in trough and peak seated diastolic and systolic blood pressure. Antihypertensive effects increased with increasing doses and reached a plateau at > or = 300 mg. Irbesartan 150 mg provided placebo-subtracted reductions in trough seated systolic and diastolic blood pressure of approximately 8 and approximately 5 mm Hg, respectively, with 56% of patients displaying a favorable response. In conclusion, irbesartan provides clinically significant blood pressure lowering, with a clear relationship between (log) dose and antihypertensive effect.

A randomised, double-blind comparison of the angiotensin II receptor antagonist, irbesartan, with the full dose range of enalapril for the treatment of mild-to-moderate hypertension.

OBJECTIVE: To compare the anti-hypertensive efficacy, safety, and tolerability of irbesartan with those of the full dose range of enalapril in patients with mild-to-moderate hypertension. DESIGN AND METHODS: A total of 200 patients were randomised to irbesartan 75 mg or enalapril 10 mg (once daily). Doses were doubled at Weeks 4 and/or 8 if seated diastolic blood pressure (DBP) was > or = 90 mm Hg. Trough blood pressure was measured after completion of a 4- to 5-week placebo lead-in period and again after 2, 4, 8, and 12 weeks of treatment. MAIN OUTCOME MEASURES: Efficacy was evaluated by determining the change from baseline in trough seated blood pressure and the proportion of patients normalised (seated DBP <90 mm Hg) at Week 12. Safety and tolerability were assessed by adverse events reported by physicians, by patients in response to a specific-symptoms questionnaire, by open-ended questioning of patients by physicians, and by clinical laboratory evaluations. RESULTS: Both treatments significantly lowered blood pressure with no significant difference in efficacy between treatment groups. At Week 12, the percentage of patients titrated to either enalapril 40 mg or irbesartan 300 mg was 24% and 28%, respectively. The frequency of overall adverse events was similar in both groups. The incidence of cough in the enalapril and irbesartan groups was 17% and 10%, respectively. In contrast to other AII receptor antagonists, there was no change in uric acid concentrations with irbesartan. CONCLUSIONS: Irbesartan was as effective as the full dose range of enalapril. Irbesartan also demonstrated an excellent tolerability profile.

Comparison of the angiotensin II receptor antagonist irbesartan with atenolol for treatment of hypertension.

In this multicenter, double-blind study, the antihypertensive efficacy and safety of irbesartan were compared with those of atenolol in patients with mild-to-moderate hypertension. Following a 4- to 5-week placebo lead-in period, 231 patients with seated diastolic blood pressure (SeDBP) 95-110 mmHg were randomized to irbesartan 75 mg or atenolol 50 mg once daily for 24 weeks. Doses were doubled at Week 6 for SeDBP > or = 90 mmHg. At Week 12, or anytime thereafter, doses were doubled for SeDBP > or = 90 mmHg if not done at Week 6, and hydrochlorothiazide and then nifedipine were added. Efficacy was determined by change from baseline in blood pressure and by therapeutic response rates. Safety was assessed by monitoring adverse events (AEs). Both treatments significantly lowered blood pressure from baseline. There were no significant differences between treatment groups with respect to blood pressure changes or therapeutic response. Atenolol significantly reduced seated heart rate compared with irbesartan at Week 12. The incidences of serious AEs and discontinuations due to AEs were approximately twice as high in the atenolol group compared with the irbesartan group. Thus, in comparison to atenolol, irbesartan < or = 150 mg provided at least equivalent blood pressure control while demonstrating an excellent safety and tolerability profile.

A multinational study of the effects of low-dose pravastatin in patients with non-insulin-dependent diabetes mellitus and hypercholesterolemia. Pravastatin Multinational Study Group for Diabetes.

This multinational, 16-week, randomized, double-blind, placebo-controlled study evaluated the efficacy and safety of low-dose pravastatin in 325 patients with non-insulin-dependent diabetes mellitus (NIDDM) and hypercholesterolemia [serum total cholesterol concentrations of 5.2-7.8 mmol/l (200 to 300 mg/dl)]. Patients were randomized to receive pravastatin 10 mg or matching placebo with doubling of the dose after 8 weeks if predefined target levels for total cholesterol [(i.e., < 5.2 mmol/l (200 mg/dl) or > 15% decrease from baseline] had not been achieved. At Week 16, pravastatin-treated patients showed a 21.4% decrease in serum low-density lipoprotein cholesterol (LDL-C) and a 13.5% reduction in serum total cholesterol (TC) concentrations (p < 0.001 compared with placebo). Levels of triglycerides (TG) were reduced 9.6% during pravastatin treatment (p < 0.05 compared with placebo) while high-density lipoprotein cholesterol (HDL-C) levels were increased 4.4% (p = NS). Adverse events and laboratory test abnormalities were similar among patients treated with pravastatin or placebo. Glycosylated hemoglobin (HbA1C) levels remained unchanged. The results of this study demonstrate that low-dose pravastatin is effective and well tolerated for lowering elevated cholesterol concentrations during short-term treatment of patients with NIDDM and hypercholesterolemia.

Pravastatin experience in elderly and non-elderly patients.

Epidemiologic evidence linking elevated cholesterol concentrations and coronary heart disease (CHD) through the eighth decade of life provides a rationale for lowering cholesterol concentrations to reduce morbidity and mortality from CHD. Pravastatin, a well tolerated HMG CoA reductase inhibitor with a convenient once-daily dosing regimen, has been shown to effectively lower total and low density lipoprotein (LDL) cholesterol. Individual data from more than 1800 hypercholesterolemic patients enrolled in six double-blind, randomized, multicenter studies were pooled and then analyzed to compare the safety and efficacy of pravastatin in the elderly (i.e., patients at least 65 years old) and the non-elderly. In short-term studies (8-16 weeks), response was dose-related and similar in elderly and non-elderly subjects. Pravastatin 20 or 40 mg daily lowered total cholesterol 19-25%, LDL-cholesterol 25-33%, and triglycerides 14-23%; high density lipoprotein (HDL) cholesterol increased 5-10%. During long-term studies, improvements were sustained for more than 24 months in both the non-elderly and elderly. The incidences of adverse drug events and laboratory abnormalities were similar in the elderly and non-elderly patients in all groups (active treatment control with resin, pravastatin alone, or combination therapy). In short-term studies, treatment was discontinued because of adverse events in < 1% of all patients treated with pravastatin (all doses) or placebo. The frequency and profile of adverse events were similar among patients treated with pravastatin or placebo. In long-term studies, treatment was discontinued in 0.4% of patients in the pravastatin group and in 0.3% of the patients in the bile-acid-binding resin group. If drug therapy is warranted, pravastatin appears to be safe and effective for long-term use in elderly patients with hypercholesterolemia.

Segurança da pravastatina em ensaios clínicos a longo prazo realizados nos Estados Unidos / Pravastatin safety in long term clinical trials in United States

A segurança da pravastatina, um inibidor seletivo hidrofílico da HMG-CoA redutase, foi avaliada em 1.142 pacientes adultos hipercolesterolêmicos em seis ensaios clínicos multicêntricos realizados nos Estados Unidos. Todos os ensaios foram aleatórios, duplo-cegos e controlados por placebo ao menos nas primeiras oito a 16 semanas, mantendo-se a seguir o tratamento a longo prazo com pravastatina em esquema duplo-cego ou aberto, com ou sem outras drogas redutoras de lipídios; o controle ativo primário foi a resina biliar de ligaçao a ácidos. Nao houve diferenças entre os grupos de pravastatina e placebo com relaçao às taxas globais de reaçoes adversas atribuíveis à droga. Somente erupçoes cutâneas (rash) ocorreram com maior freqúência estatística (p < 0,01) nos pacientes tratados com pravastina. Essas erupçoes geralmente eram leves e transitórias e somente 1,3 por cento dos casos relatados em pacientes tratados com pravastatina estavam possivelmente relacionados à terapia. Durante um período médio de tratamento de 18 meses, as razoes mais freqüentes para a interrupçao da administraçao de pravastatina foram queixas abdominais leves (1,4 por cento dos pacientes) e aumentos assintomáticos das transaminases hepáticas (1,0 por cento dos pacientes). Os valores médios de ALAT e ASAT aumentaram ligeiramente, atingindo um patamar estável após as primeiras oito semanas de terapia. Nenhuma ocorrência de enzimas hepáticas anormais entre os pacientes tratados com pravastina foi associada a doença clínica. Aumentos semelhantes das transaminases hepáticas também foram observados nos pacientes tratados com resina. Em geral, a pravastatina foi bem tolerada e aparentemente nao afetou os músculos esqueléticos, o sono ou o desenvolvimento de catarata.