Lipoprotein(a) Blood Levels and Cardiovascular Risk Reduction With Icosapent Ethyl

BACKGROUND

Elevated lipoprotein(a) (Lp[a]) concentrations are associated with increased cardiovascular event risk even in the presence of well-controlled low-density lipoprotein cholesterol levels, but few treatments are documented to reduce this residual risk.

OBJECTIVES

The aim of this post hoc analysis of REDUCE-IT (Reduction of Cardiovascular Events with Icosapent Ethyl-Intervention Trial) was to explore the cardiovascular benefit of icosapent ethyl (IPE) across a range of Lp(a) levels.

METHODS

A total of 8,179 participants receiving statin therapy with established cardiovascular disease or age ≥50 years with diabetes and ≥1 additional risk factor, fasting triglyceride 1.69 to 5.63 mmol/L, and low-density lipoprotein cholesterol 1.06 to 2.59 mmol/L were randomized to receive 2 g twice daily of IPE or matching placebo. Relationships between continuous baseline Lp(a) mass concentration and risk for first and total (first and subsequent) major adverse cardiovascular events (MACE) were analyzed, along with the effects of IPE on first MACE among those with Lp(a) concentrations ≥50 or <50 mg/dL.

RESULTS

Among 7,026 participants (86% of those randomized) with baseline Lp(a) assessments, the median concentration was 11.6 mg/dL (Q1-Q3: 5.0-37.4 mg/dL). Lp(a) had significant relationships with first and total MACE (P < 0.0001), while event reductions with IPE did not vary across the range of Lp(a) (interaction P > 0.10). IPE significantly reduced first MACE in subgroups with concentrations ≥50 and <50 mg/dL.

CONCLUSIONS

Baseline Lp(a) concentration was prognostic for MACE among participants with elevated triglyceride levels receiving statin therapy. Importantly, IPE consistently reduced MACE across a range of Lp(a) levels, including among those with clinically relevant elevations.

Effectiveness of icosapent ethyl on first and total cardiovascular events in patients with metabolic syndrome, but without diabetes: REDUCE-IT MetSyn

Aims

Metabolic syndrome (MetSyn) is associated with high risk of cardiovascular (CV) events, irrespective of statin therapy. In the overall REDUCE-IT study of statin-treated patients, icosapent ethyl (IPE) reduced the risk of the primary composite endpoint (CV death, non-fatal myocardial infarction, non-fatal stroke, coronary revascularization, or unstable angina requiring hospitalization) and the key secondary composite endpoint (CV death, non-fatal myocardial infarction, or non-fatal stroke).

Methods and results

REDUCE-IT was an international, double-blind trial that randomized 8179 high CV risk statin-treated patients with controlled LDL cholesterol and elevated triglycerides, to IPE 4 g/day or placebo. The current study evaluated the pre-specified patient subgroup with a history of MetSyn, but without diabetes at baseline. Among patients with MetSyn but without diabetes at baseline (n = 2866), the majority (99.8%) of this subgroup was secondary prevention patients. Icosapent ethyl use was associated with a 29% relative risk reduction for the first occurrence of the primary composite endpoint [hazard ratio: 0.71; 95% confidence interval (CI): 0.59-0.84; P < 0.0001, absolute risk reduction (ARR) = 5.9%; number needed to treat = 17] and a 41% reduction in total (first plus subsequent) events [rate ratio: 0.59; (95% CI: 0.48-0.72); P < 0.0001] compared with placebo. The risk for the key secondary composite endpoint was reduced by 20% (P = 0.05) and a 27% reduction in fatal/non-fatal MI (P = 0.03), 47% reduction in urgent/emergent revascularization (P < 0.0001), and 58% reduction in hospitalization for unstable angina (P < 0.0001). Non-statistically significant reductions were observed in cardiac arrest (44%) and sudden cardiac death (34%).

Conclusion

In statin-treated patients with a history of MetSyn, IPE significantly reduced the risk of first and total CV events in REDUCE-IT. The large relative and ARRs observed supports IPE as a potential therapeutic consideration for patients with MetSyn at high CV risk. Registration REDUCE-IT ClinicalTrials.gov number: NCT01492361.

Cardiovascular Benefits of Icosapent Ethyl in Patients With and Without Atrial Fibrillation in REDUCE-IT

Background In REDUCE-IT (Reduction of Cardiovascular Events With Icosapent Ethyl-Intervention Trial), icosapent ethyl (IPE) versus placebo) reduced cardiovascular death, myocardial infarction, stroke, coronary revascularization, or unstable angina requiring hospitalization, but was associated with increased atrial fibrillation/atrial flutter (AF) hospitalization (3.1% IPE versus 2.1% placebo; P=0.004). Methods and Results We performed post hoc efficacy and safety analyses of patients with or without prior AF (before randomization) and with or without in-study time-varying AF hospitalization to assess relationships of IPE (versus placebo) and outcomes. In-study AF hospitalization event rates were higher in patients with prior AF (12.5% versus 6.3%, IPE versus placebo; P=0.007) versus without prior AF (2.2% versus 1.6%, IPE versus placebo; P=0.09). Serious bleeding rates trended higher in patients with (7.3% versus 6.0%, IPE versus placebo; P=0.59) versus without prior AF (2.3% versus 1.7%, IPE versus placebo; P=0.08). With IPE, serious bleeding trended higher regardless of prior AF (interaction P value [Pint]=0.61) or postrandomization AF hospitalization (Pint=0.66). Patients with prior AF (n=751, 9.2%) versus without prior AF (n=7428, 90.8%) had similar relative risk reductions of the primary composite and key secondary composite end points with IPE versus placebo (Pint=0.37 and Pint=0.55, respectively). Conclusions In REDUCE-IT, in-study AF hospitalization rates were higher in patients with prior AF especially in those randomized to IPE. Although serious bleeding trended higher in those randomized to IPE versus placebo over the course of the study, serious bleeding was not different regardless of prior AF or in-study AF hospitalization. Patients with prior AF or in-study AF hospitalization had consistent relative risk reductions across primary, key secondary, and stroke end points with IPE. Registration URL: https://clinicaltrials.gov/ct2/show/NCT01492361; Unique Identifier: NCT01492361.

Prevention of Cardiovascular Events and Mortality With Icosapent Ethyl in Patients With Prior Myocardial Infarction

BACKGROUND

REDUCE-IT was a double-blind trial that randomized 8,179 statin-treated patients with controlled low-density lipoprotein cholesterol and moderately elevated triglycerides to icosapent ethyl (IPE) or placebo. There was a significant reduction in the primary endpoint, including death from cardiovascular (CV) causes. The specific impact of IPE among patients with prior myocardial infarction (MI) was unknown.

OBJECTIVES

Our goal was to examine the benefit of IPE on ischemic events among patients with prior MI in REDUCE-IT.

METHODS

We performed post hoc analyses of patients with prior MI. The primary endpoint was CV death, MI, stroke, coronary revascularization, or hospitalization for unstable angina. The key secondary endpoint was CV death, MI, or stroke.

RESULTS

A total of 3,693 patients had a history of prior MI. The primary endpoint was reduced from 26.1% to 20.2% with IPE vs placebo; HR: 0.74 (95% CI: 0.65-0.85; P = 0.00001). The key secondary endpoint was reduced from 18.0% to 13.3%; HR: 0.71 (95% CI: 0.61-0.84; P = 0.00006). There was also a significant 35% relative risk reduction in total ischemic events (P = 0.0000001), a 34% reduction in MI (P = 0.00009), a 30% reduction in CV death (P = 0.01), and a 20% lower rate of all-cause mortality (P = 0.054), although there was a slight increase in atrial fibrillation. Sudden cardiac death and cardiac arrest were also significantly reduced by 40% and 56%, respectively.

CONCLUSIONS

Patients with a history of prior MI in REDUCE-IT treated with IPE demonstrated large and significant relative and absolute risk reductions in ischemic events, including CV death. (A Study of AMR101 to Evaluate Its Ability to Reduce Cardiovascular Events in High Risk Patients With Hypertriglyceridemia and on Statin. The Primary Objective is to Evaluate the Effect of 4 g/Day AMR101 for Preventing the Occurrence of a First Major Cardiovascular Event. [REDUCE-IT]; NCT01492361).

Treatment With Icosapent Ethyl to Reduce Ischemic Events in Patients With Prior Percutaneous Coronary Intervention: Insights From REDUCE-IT PCI

Background

Patients who undergo percutaneous coronary intervention (PCI) are at increased risk for recurrent cardiovascular events despite aggressive medical therapy.

Methods and Results

This post hoc analysis focused on the subset of patients with prior PCI enrolled in REDUCE‐IT (Reduction of Cardiovascular Events With Icosapent Ethyl–Intervention Trial), a multicenter, randomized, double‐blind, placebo‐controlled trial of icosapent ethyl versus placebo. Icosapent ethyl was added to statins in patients with low‐density lipoprotein cholesterol <100 mg/dL and fasting triglycerides 135–499 mg/dL. The primary end point was a composite of cardiovascular death, nonfatal myocardial infarction, nonfatal stroke, coronary revascularization, or unstable angina requiring hospitalization. There were 8179 patients randomized in REDUCE‐IT followed for a median of 4.9 years, and 3408 (41.7%) of them had a prior PCI with a median follow‐up of 4.8 years. These patients were randomized a median of 2.9 years (11 days to 30.7 years) after PCI. Among patients treated with icosapent ethyl versus placebo, there was a 34% reduction in the primary composite end point (hazard ratio [HR], 0.66; 95% CI, 0.58–0.76; P<0.001; number needed to treat^{4.8 years}=12) and a 34% reduction in the key secondary composite end point of cardiovascular death, nonfatal myocardial infarction, or nonfatal stroke (HR, 0.66; 95% CI, 0.56–0.79; P<0.001; NNT^{4.8 years}=19) versus placebo. Similarly, large reductions occurred in total coronary revascularizations and revascularization subtypes. There was also a 39% reduction in total events (rate ratio, 0.61; 95% CI, 0.52–0.72; P<0.001).

Conclusions

Among patients treated with statins with elevated triglycerides and a history of prior PCI, icosapent ethyl substantially reduced the risk of recurrent events during an average of ~5 years of follow‐up with a number needed to treat of only 12.

Registration

URL: https://www.clinicaltrials.gov; Unique identifier: NCT01492361.

Icosapent Ethyl Reduces Ischemic Events in Patients With a History of Previous Coronary Artery Bypass Grafting: REDUCE-IT CABG

BACKGROUND

Despite advances in surgery and pharmacotherapy, there remains significant residual ischemic risk after coronary artery bypass grafting surgery.

METHODS

In REDUCE-IT (Reduction of Cardiovascular Events With Icosapent Ethyl-Intervention Trial), a multicenter, placebo-controlled, double-blind trial, statin-treated patients with controlled low-density lipoprotein cholesterol and mild to moderate hypertriglyceridemia were randomized to 4 g daily of icosapent ethyl or placebo. They experienced a 25% reduction in risk of a primary efficacy end point (composite of cardiovascular death, myocardial infarction, stroke, coronary revascularization, or hospitalization for unstable angina) and a 26% reduction in risk of a key secondary efficacy end point (composite of cardiovascular death, myocardial infarction, or stroke) when compared with placebo. The current analysis reports on the subgroup of patients from the trial with a history of coronary artery bypass grafting.

RESULTS

Of the 8179 patients randomized in REDUCE-IT, a total of 1837 (22.5%) had a history of coronary artery bypass grafting, with 897 patients randomized to icosapent ethyl and 940 to placebo. Baseline characteristics were similar between treatment groups. Randomization to icosapent ethyl was associated with a significant reduction in the primary end point (hazard ratio [HR], 0.76 [95% CI, 0.63-0.92]; P=0.004), in the key secondary end point (HR, 0.69 [95% CI, 0.56-0.87]; P=0.001), and in total (first plus subsequent or recurrent) ischemic events (rate ratio, 0.64 [95% CI, 0.50-0.81]; P=0.0002) compared with placebo. This yielded an absolute risk reduction of 6.2% (95% CI, 2.3%-10.2%) in first events, with a number needed to treat of 16 (95% CI, 10-44) during a median follow-up time of 4.8 years. Safety findings were similar to the overall study: beyond an increased rate of atrial fibrillation/flutter requiring hospitalization for at least 24 hours (5.0% vs 3.1%; P=0.03) and a nonsignificant increase in bleeding, occurrences of adverse events were comparable between groups.

CONCLUSIONS

In REDUCE-IT patients with a history of coronary artery bypass grafting, treatment with icosapent ethyl was associated with significant reductions in first and recurrent ischemic events. Registration: URL: https://www.clinicaltrials.gov; Unique identifier: NCT01492361.

Benefits of Icosapent Ethyl Across the Range of Kidney Function in Patients With Established Cardiovascular Disease or Diabetes: REDUCE-IT RENAL

Supplemental Digital Content is available in the text.

Chronic kidney disease is associated with adverse outcomes among patients with established cardiovascular disease (CVD) or diabetes. Commonly used medications to treat CVD are less effective among patients with reduced kidney function.

Comparative Reductions in Investigator-Reported and Adjudicated Ischemic Events in REDUCE-IT

BACKGROUND

REDUCE-IT (Reduction of Cardiovascular Events With Icosapent Ethyl-Intervention Trial) randomized statin-treated patients with elevated triglycerides to icosapent ethyl (IPE) or placebo. There was a significant reduction in adjudicated events, including the primary endpoint (cardiovascular [CV] death, myocardial infarction [MI], stroke, coronary revascularization, unstable angina requiring hospitalization) and key secondary endpoint (CV death, MI, stroke) with IPE.

OBJECTIVES

The purpose of this study was to determine the effects of IPE on investigator-reported events.

METHODS

Potential endpoints were collected by blinded site investigators and subsequently adjudicated by a blinded Clinical Endpoint Committee (CEC) according to a prespecified charter. Investigator-reported events were compared with adjudicated events for concordance.

RESULTS

There was a high degree of concordance between investigator-reported and adjudicated endpoints. The simple Kappa statistic between CEC-adjudicated vs site-reported events for the primary endpoint was 0.89 and for the key secondary endpoint was 0.90. Based on investigator-reported events in 8,179 randomized patients, IPE significantly reduced the rate of the primary endpoint (19.1% vs 24.6%; HR: 0.74 [95% CI: 0.67-0.81]; P < 0.0001) and the key secondary endpoint (10.5% vs 13.6%; HR: 0.75 [95% CI: 0.66-0.85]; P < 0.0001). Among adjudicated events, IPE similarly reduced the rate of the primary and key secondary endpoints.

CONCLUSIONS

IPE led to consistent, significant reductions in CV events, including MI and coronary revascularization, as determined by independent, blinded CEC adjudication as well as by blinded investigator-reported assessment. These results highlight the robust evidence for the substantial CV benefits of IPE seen in REDUCE-IT and further raise the question of whether adjudication of CV outcome trial endpoints is routinely required in blinded, placebo-controlled trials. (Evaluation of the Effect of AMR101 on Cardiovascular Health and Mortality in Hypertriglyceridemic Patients With Cardiovascular Disease or at High Risk for Cardiovascular Disease: REDUCE-IT [Reduction of Cardiovascular Events With EPA - Intervention Trial]; NCT01492361).

Reduction in Revascularization With Icosapent Ethyl: Insights From REDUCE-IT Revascularization Analyses

Supplemental Digital Content is available in the text.

Background:

Patients with elevated triglycerides despite statin therapy have increased risk for ischemic events, including coronary revascularizations.

Methods:

REDUCE-IT (The Reduction of Cardiovascular Events with Icosapent Ethyl–Intervention Trial), a multicenter, double-blind, placebo-controlled trial, randomly assigned statin-treated patients with elevated triglycerides (135–499 mg/dL), controlled low-density lipoprotein (41–100 mg/dL), and either established cardiovascular disease or diabetes plus other risk factors to receive icosapent ethyl 4 g/d or placebo. The primary and key secondary composite end points were significantly reduced. Prespecified analyses examined all coronary revascularizations, recurrent revascularizations, and revascularization subtypes.

Results:

A total of 8179 randomly assigned patients were followed for 4.9 years (median). First revascularizations were reduced to 9.2% (22.5/1000 patient-years) with icosapent ethyl versus 13.3% (33.7/1000 patient-years) with placebo (hazard ratio, 0.66 [95% CI, 0.58–0.76]; P<0.0001; number needed to treat for 4.9 years=24); similar reductions were observed in total (first and subsequent) revascularizations (negative binomial rate ratio, 0.64 [95% CI, 0.56–0.74]; P<0.0001), and across elective, urgent, and emergent revascularizations. Icosapent ethyl significantly reduced percutaneous coronary intervention (hazard ratio, 0.68 [95% CI, 0.59–0.79]; P<0.0001) and coronary artery bypass grafting (hazard ratio, 0.61 [95% CI, 0.45–0.81]; P=0.0005).

Conclusions:

Icosapent ethyl reduced the need for first and subsequent coronary revascularizations in statin-treated patients with elevated triglycerides and increased cardiovascular risk. To our knowledge, icosapent ethyl is the first non–low-density lipoprotein–lowering treatment that has been shown to reduce coronary artery bypass grafting in a blinded, randomized trial.

Registration:

URL: https://www.clinicaltrials.gov; Unique identifier: NCT01492361.

REDUCE-IT USA: Results From the 3146 Patients Randomized in the United States

Supplemental Digital Content is available in the text.

Some trials have found that patients from the United States derive less benefit than patients enrolled outside the United States. This prespecified REDUCE-IT (Reduction of Cardiovascular Events with Icosapent Ethyl - Intervention Trial) subgroup analysis was conducted to determine the degree of benefit of icosapent ethyl in the United States.

Icosapent ethyl reduces atherogenic markers in high-risk statin-treated patients with stage 3 chronic kidney disease and high triglycerides

Objective: Patients with chronic kidney disease (CKD) have increased cardiovascular disease (CVD) risk, likely driven by atherogenic and inflammatory markers beyond low-density lipoprotein cholesterol (LDL-C). The objective of this hypothesis-generating post hoc subgroup analysis was to explore the effects of icosapent ethyl at 2 or 4 g/day (prescription pure ethyl ester of the omega-3 fatty acid eicosapentaenoic acid [EPA]) on atherogenic lipid, apolipoprotein, inflammatory parameters (high-sensitivity C-reactive protein [hsCRP], lipoprotein-associated phospholipase A₂ [Lp-PLA₂]), and oxidative parameters (oxidized-LDL [ox-LDL]) in statin-treated patients from ANCHOR with stage 3 CKD.Methods: The 12-week ANCHOR study evaluated icosapent ethyl in 702 statin-treated patients at increased CVD risk with triglycerides (TG) 200-499 mg/dL despite controlled LDL-C (40-99 mg/dL). This post-hoc analysis included patients from ANCHOR with stage 3 CKD (estimated glomerular filtration rate [eGFR] ≤60 mL/min/1.73 m² for ≥3 months) randomized to icosapent ethyl 4 g/day (n = 19), 2 g/day (n = 30), or placebo (n = 36).Results: At the prescription dose of 4 g/day, icosapent ethyl significantly reduced TG (-16.9%; P = 0.0074) and other potentially atherogenic lipids/lipoproteins, ox-LDL, hsCRP, and Lp-PLA₂, and increased plasma and red blood cell EPA levels (+879% and +579%, respectively; both P < 0.0001) versus placebo. Icosapent ethyl did not significantly alter eGFR or serum creatinine. Safety and tolerability were similar to placebo.Conclusions: In patients with stage 3 CKD at high CVD risk with persistent high TG despite statins, icosapent ethyl 4 g/day reduced potentially atherogenic and other cardiovascular risk factors without raising LDL-C, with safety similar to placebo. These findings suggest prospective investigation may be warranted.

Effects of Icosapent Ethyl on Total Ischemic Events: From REDUCE-IT

BACKGROUND

In time-to-first-event analyses, icosapent ethyl significantly reduced the risk of ischemic events, including cardiovascular death, among patients with elevated triglycerides receiving statins. These patients are at risk for not only first but also subsequent ischemic events.

OBJECTIVES

Pre-specified analyses determined the extent to which icosapent ethyl reduced total ischemic events.

METHODS

REDUCE-IT (Reduction of Cardiovascular Events with Icosapent Ethyl-Intervention Trial) randomized 8,179 statin-treated patients with triglycerides ≥135 and <500 mg/dl (median baseline of 216 mg/dl) and low-density lipoprotein cholesterol >40 and ≤100 mg/dl (median baseline of 75 mg/dl), and a history of atherosclerosis (71% patients) or diabetes (29% patients) to icosapent ethyl 4 g/day or placebo. The main outcomes were total (first and subsequent) primary composite endpoint events (cardiovascular death, nonfatal myocardial infarction, nonfatal stroke, coronary revascularization, or hospitalization for unstable angina) and total key secondary composite endpoint events (cardiovascular death, nonfatal myocardial infarction, or nonfatal stroke). As a pre-specified statistical method, we determined differences in total events using negative binomial regression. We also determined differences in total events using other statistical models, including Andersen-Gill, Wei-Lin-Weissfeld (Li and Lagakos modification), both pre-specified, and a post hoc joint frailty analysis.

RESULTS

In 8,179 patients, followed for a median of 4.9 years, 1,606 (55.2%) first primary endpoint events and 1,303 (44.8%) subsequent primary endpoint events occurred (which included 762 second events, and 541 third or more events). Overall, icosapent ethyl reduced total primary endpoint events (61 vs. 89 per 1,000 patient-years for icosapent ethyl versus placebo, respectively; rate ratio: 0.70; 95% confidence interval: 0.62 to 0.78; p < 0.0001). Icosapent ethyl also reduced totals for each component of the primary composite endpoint, as well as the total key secondary endpoint events (32 vs. 44 per 1,000 patient-years for icosapent ethyl versus placebo, respectively; rate ratio: 0.72; 95% confidence interval: 0.63 to 0.82; p < 0.0001).

CONCLUSIONS

Among statin-treated patients with elevated triglycerides and cardiovascular disease or diabetes, multiple statistical models demonstrate that icosapent ethyl substantially reduces the burden of first, subsequent, and total ischemic events. (Reduction of Cardiovascular Events With Icosapent Ethyl-Intervention Trial [REDUCE-IT]; NCT01492361).

Cardiovascular Risk Reduction with Icosapent Ethyl for Hypertriglyceridemia

BACKGROUND

Patients with elevated triglyceride levels are at increased risk for ischemic events. Icosapent ethyl, a highly purified eicosapentaenoic acid ethyl ester, lowers triglyceride levels, but data are needed to determine its effects on ischemic events.

METHODS

We performed a multicenter, randomized, double-blind, placebo-controlled trial involving patients with established cardiovascular disease or with diabetes and other risk factors, who had been receiving statin therapy and who had a fasting triglyceride level of 135 to 499 mg per deciliter (1.52 to 5.63 mmol per liter) and a low-density lipoprotein cholesterol level of 41 to 100 mg per deciliter (1.06 to 2.59 mmol per liter). The patients were randomly assigned to receive 2 g of icosapent ethyl twice daily (total daily dose, 4 g) or placebo. The primary end point was a composite of cardiovascular death, nonfatal myocardial infarction, nonfatal stroke, coronary revascularization, or unstable angina. The key secondary end point was a composite of cardiovascular death, nonfatal myocardial infarction, or nonfatal stroke.

RESULTS

A total of 8179 patients were enrolled (70.7% for secondary prevention of cardiovascular events) and were followed for a median of 4.9 years. A primary end-point event occurred in 17.2% of the patients in the icosapent ethyl group, as compared with 22.0% of the patients in the placebo group (hazard ratio, 0.75; 95% confidence interval [CI], 0.68 to 0.83; P<0.001); the corresponding rates of the key secondary end point were 11.2% and 14.8% (hazard ratio, 0.74; 95% CI, 0.65 to 0.83; P<0.001). The rates of additional ischemic end points, as assessed according to a prespecified hierarchical schema, were significantly lower in the icosapent ethyl group than in the placebo group, including the rate of cardiovascular death (4.3% vs. 5.2%; hazard ratio, 0.80; 95% CI, 0.66 to 0.98; P=0.03). A larger percentage of patients in the icosapent ethyl group than in the placebo group were hospitalized for atrial fibrillation or flutter (3.1% vs. 2.1%, P=0.004). Serious bleeding events occurred in 2.7% of the patients in the icosapent ethyl group and in 2.1% in the placebo group (P=0.06).

CONCLUSIONS

Among patients with elevated triglyceride levels despite the use of statins, the risk of ischemic events, including cardiovascular death, was significantly lower among those who received 2 g of icosapent ethyl twice daily than among those who received placebo. (Funded by Amarin Pharma; REDUCE-IT ClinicalTrials.gov number, NCT01492361 .).

Lipid Effects of Icosapent Ethyl in Women with Diabetes Mellitus and Persistent High Triglycerides on Statin Treatment: ANCHOR Trial Subanalysis

Background: High triglycerides (TG) and diabetes mellitus type 2 (DM2) are stronger predictors of cardiovascular disease (CVD) in women than in men, but few randomized, controlled clinical trials have investigated lipid-lowering interventions in women and none have reported results specifically in women with high TG and DM2. Icosapent ethyl (Vascepa) is pure prescription eicosapentaenoic acid (EPA) ethyl ester approved at 4 g/day as an adjunct to diet to reduce TG ≥500 mg/dL.

Methods: The 12-week ANCHOR trial randomized 702 statin-treated patients (73% with DM; 39% women) at increased CVD risk with TG 200–499 mg/dL despite controlled low-density lipoprotein cholesterol (LDL-C; 40–99 mg/dL) to receive icosapent ethyl 2 g/day, 4 g/day, or placebo. This post hoc analysis included 146 women with DM2 (97% white, mean age 62 years) randomized to icosapent ethyl 4 g/day (n = 74) or placebo (n = 72).

Results: Icosapent ethyl significantly reduced TG (−21.5%; p < 0.0001) without increasing LDL-C and lowered other potentially atherogenic lipid/lipoprotein, apolipoprotein, and inflammatory parameters versus placebo. Icosapent ethyl increased EPA levels in plasma (+639%; p < 0.0001; n = 49) and red blood cells (+599%; p < 0.0001; n = 47) versus placebo. Safety and tolerability of icosapent ethyl were generally similar to placebo.

Conclusion: In women with DM2 at high CVD risk with persistently high TG on statins, icosapent ethyl 4 g/day reduced potentially atherogenic parameters with safety and tolerability comparable to placebo. Potential CVD benefits of icosapent ethyl are being tested in ∼8000 men and women at high CVD risk with high TG on statins in the ongoing Reduction of Cardiovascular Events with Icosapent Ethyl - Intervention Trial (REDUCE-IT) cardiovascular (CV) outcome trial.

Rationale and design of REDUCE-IT: Reduction of Cardiovascular Events with Icosapent Ethyl-Intervention Trial

Residual cardiovascular risk persists despite statins, yet outcome studies of lipid-targeted therapies beyond low-density lipoprotein cholesterol (LDL-C) have not demonstrated added benefit. Triglyceride elevation is an independent risk factor for cardiovascular events. High-dose eicosapentaenoic acid (EPA) reduces triglyceride-rich lipoproteins without raising LDL-C. Omega-3s have postulated pleiotropic cardioprotective benefits beyond triglyceride-lowering. To date, no large, multinational, randomized clinical trial has proved that lowering triglycerides on top of statin therapy improves cardiovascular outcomes. The Reduction of Cardiovascular Events with Icosapent Ethyl-Intervention Trial (REDUCE-IT; NCT01492361) is a phase 3b randomized, double-blinded, placebo-controlled trial of icosapent ethyl, a highly purified ethyl ester of EPA, vs placebo. The main objective is to evaluate whether treatment with icosapent ethyl reduces ischemic events in statin-treated patients with high triglycerides at elevated cardiovascular risk. REDUCE-IT enrolled men or women age ≥45 years with established cardiovascular disease or age ≥50 years with diabetes mellitus and 1 additional risk factor. Randomization required fasting triglycerides ≥150 mg/dL and <500 mg/dL and LDL-C >40 mg/dL and ≤100 mg/dL with stable statin (± ezetimibe) ≥4 weeks prior to qualifying measurements. The primary endpoint is a composite of cardiovascular death, nonfatal myocardial infarction, nonfatal stroke, coronary revascularization, or unstable angina. The key secondary endpoint is the composite of cardiovascular death, nonfatal myocardial infarction, or nonfatal stroke. Several secondary, tertiary, and exploratory endpoints will be assessed. Approximately 8000 patients have been randomized at approximately 470 centers worldwide. Follow-up will continue in this event-driven trial until approximately 1612 adjudicated primary-efficacy endpoint events have occurred.

Usefulness of Icosapent Ethyl (Eicosapentaenoic Acid Ethyl Ester) in Women to Lower Triglyceride Levels (Results from the MARINE and ANCHOR Trials)

There are limited data on the efficacy and safety of triglyceride (TG)-lowering agents in women. We conducted subgroup analyses of the effects of icosapent ethyl (a high-purity prescription form of the ethyl ester of the omega-3 fatty acid, eicosapentaenoic acid) on TG levels (primary efficacy variable) and other atherogenic and inflammatory parameters in a total of 215 women with a broad range of TG levels (200-2000 mg/dl) enrolled in two 12-week placebo-controlled trials: MARINE (n = 18; placebo, n = 18) and ANCHOR (n = 91; placebo, n = 88). Icosapent ethyl 4 g/day significantly reduced TG levels from baseline to week 12 versus placebo in both MARINE (-22.7%; p = 0.0327) and ANCHOR (-21.5%; p <0.0001) without increasing low-density lipoprotein cholesterol levels. Significant improvements were also observed in non-high-density lipoprotein cholesterol levels in MARINE (-15.7%; p = 0.0082) and ANCHOR (-14.2%; p <0.0001) and total cholesterol levels in MARINE (-14.9%; p = 0.0023) and ANCHOR (-12.1%; p <0.0001), along with significant increases of >500% in eicosapentaenoic acid levels in plasma and red blood cells (all p <0.001). Icosapent ethyl was well tolerated, with adverse-event profiles comparable with findings in the overall studies. In conclusion, icosapent ethyl 4 g/day significantly reduced TG levels and other atherogenic parameters in women without increasing low-density lipoprotein cholesterol levels compared with placebo; the clinical implications of these findings are being evaluated in the REDUCtion of Cardiovascular Events With Eicosapentaenoic Acid [EPA]-Intervention Trial (REDUCE-IT) cardiovascular outcomes study.

Icosapent ethyl (eicosapentaenoic acid ethyl ester): Effects on remnant-like particle cholesterol from the MARINE and ANCHOR studies

BACKGROUND AND AIMS

Remnant-like particle cholesterol (RLP-C) is atherogenic and may increase atherosclerotic cardiovascular disease risk. Icosapent ethyl is a high-purity prescription eicosapentaenoic acid ethyl ester (approved as an adjunct to diet to reduce triglyceride [TG] levels in adult patients with TGs ≥500 mg/dL [≥5.65 mmol/L] at 4 g/day). In the MARINE and ANCHOR studies, icosapent ethyl reduced TG and other atherogenic lipid parameter levels without increasing low-density lipoprotein cholesterol (LDL-C) levels. This exploratory analysis evaluated the effects of icosapent ethyl on calculated and directly measured RLP-C.

METHODS

MARINE (TGs ≥500 and ≤2000 mg/dL [≥5.65 mmol/L and ≤22.6 mmol/L]) and ANCHOR (TGs ≥200 and <500 mg/dL [≥2.26 and <5.65 mmol/L] despite statin-controlled LDL-C) were phase 3, 12-week, double-blind studies that randomized adult patients to icosapent ethyl 4 g/day, 2 g/day, or placebo. This analysis assessed median percent change from baseline to study end in directly measured (immunoseparation assay) RLP-C levels (MARINE, n = 218; ANCHOR, n = 252) and calculated RLP-C levels in the full populations.

RESULTS

Icosapent ethyl 4 g/day significantly reduced directly measured RLP-C levels -29.8% (p = 0.004) in MARINE and -25.8% (p = 0.0001) in ANCHOR versus placebo, and also reduced directly measured RLP-C levels to a greater extent in subgroups with higher versus lower baseline TG levels, in patients receiving statins versus no statins (MARINE), and in patients receiving medium/higher-intensity versus lower-intensity statins (ANCHOR). Strong correlations were found between calculated and directly measured RLP-C for baseline, end-of-treatment, and percent change values in ANCHOR and MARINE (0.73-0.92; p < 0.0001 for all).

CONCLUSIONS

Icosapent ethyl 4 g/day significantly reduced calculated and directly measured RLP-C levels versus placebo in patients with elevated TG levels from the MARINE and ANCHOR studies.

Icosapent Ethyl (Eicosapentaenoic Acid Ethyl Ester): Effects Upon High-Sensitivity C-Reactive Protein and Lipid Parameters in Patients With Metabolic Syndrome

BACKGROUND

The aim of this analysis was to examine the effects of icosapent ethyl (eicosapentaenoic acid ethyl ester, IPE) on high-sensitivity C-reactive protein (hsCRP) and lipid parameters in patients with metabolic syndrome, with and without stable statin therapy.

METHODS

This post hoc exploratory analysis evaluated patients with metabolic syndrome treated with IPE 4 grams/day, IPE 2 grams/day, or placebo in phase 3, randomized, placebo-controlled studies entitled: MARINE [triglyceride (TG) levels ≥500 and ≤2000 mg/dL] and ANCHOR [TG levels ≥200 and <500 mg/dL, despite low-density lipoprotein cholesterol (LDL-C) control with stable statin therapy].

RESULTS

Compared with placebo in patients with metabolic syndrome in MARINE (n=204) and ANCHOR (n=645), at the approved dose of 4 grams/day, IPE significantly lowered hsCRP levels 40.0% (P=0.0007) in MARINE and 23.0% (P=0.0003) in ANCHOR. Compared with placebo in MARINE, which included patients with and without statin therapy, IPE 4 grams/day significantly reduced hsCRP levels 78.0% in statin-treated patients (P=0.0035, n=16). Compared with placebo in MARINE, IPE 4 grams/day significantly reduced TG levels (35.0%; P<0.0001), non-high-density lipoprotein cholesterol (non-HDL-C; 19.9%; P<0.0001), and apolipoprotein B levels (ApoB) (9.1%; P=0.0015) without raising LDL-C levels. Compared with placebo in ANCHOR, IPE 4 grams/day significantly reduced TG (21.7%; P<0.0001), non-HDL-C (13.5%; P<0.0001), ApoB (8.8%; P<0.0001), LDL-C (5.2%; P=0.0236), and HDL-C levels (4.0%; P=0.0053).

CONCLUSIONS

Compared with placebo, IPE 4 grams/day significantly lowered hsCRP levels and improved lipids without raising LDL-C levels in patients with metabolic syndrome and high (≥200 and <500 mg/dL) or very high (≥500 and ≤2000 mg/dL) TG levels, with or without stable statin therapy.

Baseline lipoprotein lipids and low-density lipoprotein cholesterol response to prescription omega-3 acid ethyl ester added to Simvastatin therapy

The present post hoc analysis of data from the COMBination of prescription Omega-3 with Simvastatin (COMBOS) study investigated the predictors of the low-density lipoprotein (LDL) cholesterol response to prescription omega-3 acid ethyl ester (P-OM3) therapy in men and women with high (200 to 499 mg/dl) triglycerides during diet plus simvastatin therapy. Subjects (n = 256 randomized) received double-blind P-OM3 4 g/day or placebo for 8 weeks combined with diet and open-label simvastatin 40 mg/day. The percentage of changes from baseline (with diet plus simvastatin) in lipids was evaluated by tertiles of baseline LDL cholesterol and triglyceride concentrations. The baseline LDL cholesterol tertile was a significant predictor of the LDL cholesterol response (p = 0.022 for the treatment by baseline tertile interaction). The median LDL cholesterol response in the P-OM3 group was +9.5% (first tertile, <80.4 mg/dl), -0.9% (second tertile), and -6.4% (third tertile, > or =99.0 mg/dl). Non-high-density lipoprotein cholesterol, very-low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, and triglyceride responses did not vary significantly by baseline LDL cholesterol tertile. The reductions in very-low-density lipoprotein cholesterol concentrations were greater than the increases in LDL cholesterol, where present, resulting in a net decrease in the concentration of cholesterol carried by atherogenic particles (non-high-density lipoprotein cholesterol) in all baseline LDL cholesterol tertiles. In conclusion, these results suggest that the increase in LDL cholesterol that occurred with the addition of P-OM3 to simvastatin therapy in subjects with mixed dyslipidemia was confined predominantly to those with low LDL cholesterol levels while receiving simvastatin monotherapy.

Long-term up to 24-month efficacy and safety of concomitant prescription omega-3-acid ethyl esters and simvastatin in hypertriglyceridemic patients

OBJECTIVE

Assess the long-term efficacy and safety of prescription omega-3-acid ethyl esters (P-OM3) coadministered with simvastatin in an extension of the Combination of Prescription Omega-3 Plus Simvastatin (COMBOS) trial.

METHODS

COMBOS included hypertriglyceridemic patients (triglyceride [TG] >or=200 mg/dL and <500 mg/dL or >or=2.26 mmol/L and <5.64 mmol/L) with low density lipoprotein cholesterol (LDL-C) level no greater than 10% above the National Cholesterol Education Program, Adult Treatment Panel III treatment goal. After an 8-week lead-in phase with simvastatin 40 mg/day (which continued throughout the trial), subjects were randomized to 8 weeks of P-OM3 4 g/day or placebo. Completers were eligible to participate in a 24-month extension study. Those who received placebo + simvastatin in COMBOS switched to open-label P-OM3 + simvastatin ('Switchers'); those who received P-OM3 + simvastatin during COMBOS continued the same regimen (open-label) in the extension phase ('Non-switchers'). The primary endpoint was the difference between Non-switchers and Switchers in median percent change in non-high-density lipoprotein-cholesterol (non-HDL-C) from COMBOS end of treatment to Month 4 of the extension phase.

RESULTS

At Month 4 from COMBOS end of treatment, non-HDL-C was reduced by a median of 9.4% in Switchers and increased by 0.9% in Non-switchers (p < 0.001). For the total population (combined Non-switcher + Switcher population), the median percent change from COMBOS baseline to Months 4, 12, and 24 was -8.3%, -7.3%, and -8.9%, respectively (all p < 0.001). This extension study revealed no unexpected safety findings. A limitation of this study was a gap between completion of COMBOS and enrollment in the extension phase for some patients; however, a post-hoc non-HDL-C sensitivity analysis performed at the 4-month primary endpoint revealed no influence of gap on study results.

CONCLUSIONS

In this 24-month extension study, P-OM3 was generally well tolerated, and produced sustained reductions in non-HDL-C levels in simvastatin-treated patients with TG levels between 200 and 500 mg/dL (2.26 mmol/L and 5.64 mmol/L).

CLINICAL TRIAL REGISTRY NUMBER

NCT00903409.

Effects of prescription omega-3-acid ethyl esters on non--high-density lipoprotein cholesterol when coadministered with escalating doses of atorvastatin

OBJECTIVE

To evaluate the effects of prescription omega-3-acid ethyl esters on non-high-density lipoprotein cholesterol (HDL-C) levels in atorvastatin-treated patients with elevated non-HDL-C and triglyceride levels.

PATIENTS AND METHODS

This study, conducted between February 15, 2007, and October 22, 2007, randomized patients with elevated non-HDL-C (>160 mg/dL) and triglyceride (>or=250 mg/dL and <or=599 mg/dL) levels to double-blind treatment with prescription omega-3-acid ethyl esters, 4 g/d, or placebo for 16 weeks. Patients also received escalating dosages of open-label atorvastatin (weeks 0-8, 10 mg/d; weeks 9-12, 20 mg/d; weeks 13-16, 40 mg/d).

RESULTS

Prescription omega-3-acid ethyl esters plus atorvastatin, 10, 20, and 40 mg/d, reduced median non-HDL-C levels by 40.2% vs 33.7% (P<.001), 46.9% vs 39.0% (P<.001), and 50.4% vs 46.3% (P<.001) compared with placebo plus the same doses of atorvastatin at the end of 8, 12, and 16 weeks, respectively. Prescription omega-3-acid ethyl esters plus atorvastatin also reduced median total cholesterol, triglyceride, and very low-density lipoprotein cholesterol levels and increased HDL-C levels to a significantly greater extent than placebo plus atorvastatin. Percent changes from baseline low-density lipoprotein-cholesterol, apolipoprotein A-I, and apolipoprotein B levels were not significantly different between groups at the end of the study.

CONCLUSION

Prescription omega-3-acid ethyl esters plus atorvastatin produced significant improvements in non-HDL-C and other lipid parameters in patients with elevated non-HDL-C and triglyceride levels.

Effect of omega-3-acid ethyl esters on steady-state plasma pharmacokinetics of atorvastatin in healthy adults

BACKGROUND

Prescription omega-3-acid ethyl esters (P-OM3) have been used as adjunctive therapy to statin drugs in patients with mixed hyperlipidemia.

OBJECTIVE

To assess the effect of concomitant administration of 4 g P-OM3 on the steady-state pharmacokinetics of the maximum recommended daily dose of atorvastatin (80 mg) in healthy volunteers.

METHODS

This was a randomized, open-label, repeated-dose, two-way crossover, drug interaction study of two treatments: 4 g of P-OM3 with 80 mg atorvastatin daily or 80 mg atorvastatin daily, each administered for 14 days under fasting conditions to 50 healthy adults.

MAIN OUTCOME MEASURES

The primary determinants of drug interaction were the ln-transformed area under the plasma concentration versus time curve (AUCtau) and maximum measured steady-state plasma concentration (C(max,ss)) over the final 24 h dosing interval (day 14) for atorvastatin and 2-hydroxyatorvastatin. Safety assessment included clinical laboratory evaluations and adverse event reporting.

RESULTS

The extent and rate of exposure (AUCtau, C(max,ss)) to atorvastatin and its active metabolites following daily administration of P-OM3 with atorvastatin (80 mg) were similar to those following the administration of atorvastatin (80 mg) alone. Both treatments were well tolerated.

CONCLUSIONS

After 14 days of dosing, the rate and extent of exposure (AUCtau, C(max,ss)) to atorvastatin and its active metabolites were similar with both treatments, indicating that administration of P-OM3 did not affect the steady-state bioavailability of orally administered atorvastatin.

Effect of omega-3-acid ethyl esters on the steady-state plasma pharmacokinetics of rosuvastatin in healthy adults

BACKGROUND

Patients with persistent hypertriglyceridemia while on statin therapy may require adjunctive lipid-lowering therapy to meet treatment goals.

OBJECTIVE

To assess the effect of concomitant administration of prescription omega-3-acid ethyl esters (P-OM3), triglyceride-lowering agents, on the steady-state pharmacokinetics of rosuvastatin.

METHODS

A randomized, open-label, repeated-dose, two-way crossover drug interaction study of two treatments - 4 g P-OM3 plus 40 mg rosuvastatin or 40 mg rosuvastatin alone administered daily for 14 days each under fasting conditions--was conducted in 48 non-smoking healthy adults.

MAIN OUTCOME MEASURES

The primary determinants of drug interaction were the ln-transformed area under the plasma concentration versus time curve [AUC(t(ss))] over the final (day 14) 24 h dosing interval and maximum measured steady-state plasma rosuvastatin concentration [C(max(ss))] on day 14. Safety was assessed by clinical and laboratory testing and recording of adverse events.

RESULTS

AUC(t(ss)) and C(max(ss)) following daily administration of rosuvastatin with P-OM3 were similar to those following monotherapy with rosuvastatin. All adverse events recorded during the study were classified as mild and self-limited.

CONCLUSIONS

Administration of P-OM3 with rosuvastatin did not affect the pharmacokinetics of rosuvastatin under steady-state conditions in healthy individuals.

Efficacy and tolerability of adding prescription omega-3 fatty acids 4 g/d to simvastatin 40 mg/d in hypertriglyceridemic patients: an 8-week, randomized, double-blind, placebo-controlled study

BACKGROUND

Patients with elevated serum triglyceride (TG) levels often have elevations in non-high-density lipoprotein cholesterol (non-HDL-C) levels as well. The National Cholesterol Education Program Adult Treatment Panel III (NCEP ATP III) has identified non-HDL-C as a secondary therapeutic target in these patients, but treatment goals may not be reached with statin monotherapy alone.

OBJECTIVE

This study evaluated the effects on non-HDL-C and other variables of adding prescription omega-3-acid ethyl esters (P-OM3; Lovaza, formerly Omacor [Reliant Pharmaceuticals, Inc., Liberty Corner, New Jersey]) to stable statin therapy in patients with persistent hypertriglyceridemia.

METHODS

This was a multicenter, randomized, double-blind, placebo-controlled, parallel-group study in adults who had received > or = 8 weeks of stable statin therapy and had mean fasting TG levels > or = 200 and < 500 mg/dL and mean low-density lipoprotein cholesterol levels < or = 10% above their NCEP ATP III goal. The study regimen consisted of an initial 8 weeks of open-label simvastatin 40 mg/d and dietary counseling, followed by 8 weeks of randomized treatment with double-blind P-OM3 4 g/d plus simvastatin 40 mg/d or placebo plus simvastatin 40 mg/d. The main outcome measure was the percent change in non-HDL-C from baseline to the end of treatment.

RESULTS

The evaluable population included 254 patients, of whom 57.5% (146) were male and 95.7% (243) were white. The mean (SD) age of the population was 59.8 (10.4) years, and the mean weight was 92.0 (19.6) kg. At the end of treatment, the median percent change in non-HDL-C was significantly greater with P-OM3 plus simvastatin compared with placebo plus simvastatin (-9.0% vs -2.2%, respectively; P < 0.001). P-OM3 plus simvastatin was associated with significant reductions in TG (29.5% vs 6.3%) and very-low-density lipoprotein cholesterol (27.5% vs 7.2%), a significant increase in high-density lipoprotein cholesterol (HDL-C) (3.4% vs -1.2%), and a significant reduction in the total cholesterol:HDL-C ratio (9.6% vs 0.7%) (all, P < 0.001 vs placebo). Adverse events (AEs) reported by > or= 1% of patients in the P-OM3 group that occurred with a higher frequency than in the group that received simvastatin alone were nasopharyngitis (4 [3.3%]), upper respiratory tract infection (4 [3.3%]), diarrhea (3 [2.5%]), and dyspepsia (3 [2.5%]). There was no significant difference in the frequency of AEs between groups. No serious AEs were considered treatment related.

CONCLUSION

In these adult, mainly white patients with persistent hypertriglyceridemia, P-OM3 plus simvastatin and dietary counseling improved non-HDL-C and other lipid and lipoprotein parameters to a greater extent than simvastatin alone.

Use of confocal linescan to document ciliary beat frequency

We present a method to document ciliary beat frequency with the linescan function of a scanning confocal microscope, using ciliated tracheal cells and free-swimming rotifers as examples. Depending on the clarity of the original data, the ciliary beat frequency can be determined from the confocal linescan directly or from an intensity linescan analysis of the original data. Fast Fourier transform treatment of the data can be used to verify the derived ciliary beat frequency. The linescan approach allows analysis of simple ciliary movements displayed by the ciliated tracheal cells, as well as complex movements performed by free-swimming rotifers while feeding.

Dose conversion and titration with a novel, once-daily, OROS osmotic technology, extended-release hydromorphone formulation in the treatment of chronic malignant or nonmalignant pain

The objective of this open-label, repeated-dose, single-treatment, multicenter study was to evaluate the outcomes associated with a standardized conversion from prior opioid therapy to a novel, once-daily, OROS osmotic technology, extended-release (ER) hydromorphone formulation in an outpatient population with chronic malignant or nonmalignant pain. The study period was divided into 3 phases: the prior opioid stabilization phase (> or =3 days), the conversion and titration phase (3-21 days), and the maintenance phase (14 days). Patients were evaluated at 5 visits during the study period. Analgesic efficacy was measured using the Brief Pain Inventory (BPI). At baseline, patients were required to have daily oral morphine equivalent requirements of > or =45 mg. Prior oral or transdermal opioid therapy was converted to single daily doses of ER hydromorphone (8, 16, 32, and 64 mg tablets) at a 5:1 (morphine equivalent to hydromorphone) ratio. Immediate-release (IR) hydromorphone was given as rescue medication for breakthrough pain. Among the 445 patients who enrolled, 404 received the study medication. Of these, 73 (18.1%) had chronic malignant pain and 331 (81.9%) had chronic nonmalignant pain. Dose stabilization (defined as a 3-day period during which the total daily dose of ER hydromorphone remained unchanged and < or =3 doses of IR hydromorphone per day were required) was attained by 73.8% of patients (298/404), of whom 70.1% (209/298) were stabilized with < or =2 titration steps. The mean +/- standard deviation (SD) time to dose stabilization was 12.1 +/- 5.7 days (range of 3 to 33 days). The mean +/- SD final daily dose of ER hydromorphone was 63.4 +/- 129.2 mg. The mean +/- SD final daily dose of IR hydromorphone was 11.5 +/- 36.4 mg, and the mean +/- SD final number of daily doses of IR hydromorphone was 1.7 +/- 1.3. Intent-to-treat and completer analysis demonstrated significant improvements in BPI ratings from prior opioid therapy to the end of ER hydromorphone therapy (P < 0.01 for all pairwise comparisons). Adverse events were consistent with those expected of an opioid agonist in such a patient group, affecting primarily the gastrointestinal and central nervous systems. This uncontrolled study delineates a regimen by which patients with chronic malignant or nonmalignant pain can be readily converted from prior opioid therapy and titrated to an appropriate maintenance dose of ER hydromorphone. Controlled longitudinal studies are required to further evaluate the use of ER hydromorphone in patients with discrete chronic malignant or nonmalignant pain conditions.

Combination hydrocodone and ibuprofen versus combination oxycodone and acetaminophen in the treatment of moderate or severe acute low back pain

BACKGROUND

Introduced in 1997, the combination of hydrocodone and ibuprofen is the only fixed-dose combination analgesic containing an opioid and ibuprofen that has been approved by the US Food and Drug Administration.

OBJECTIVE

This study compared the efficacy and tolerability of combination hydrocodone 7.5 mg and ibuprofen 200 mg (HC/IB) with those of combination oxycodone 5 mg and acetaminophen 325 mg (OX/AC) in the treatment of moderate or severe acute low back pain.

METHODS

This was a multicenter, randomized, double-blind, parallel-group, repeat-dose study lasting up to 8 days. The recommended dosing of the study medications was 1 tablet every 4 to 6 hours, not to exceed 5 tablets per day. If adequate pain relief was not obtained, patients were permitted to take up to 4 doses per day of supplemental analgesic medication-the nonopioid component of the assigned study medication (ibuprofen 200 mg or acetaminophen 325 mg). Measures of efficacy included mean daily pain relief scores (0 = no relief, 1 = slight relief, 2 = moderate relief, 3 = good relief, and 4 = complete relief), mean daily number of tablets and doses of study medication, mean daily number of tablets and doses of supplemental analgesic medication, global evaluation (poor, fair, good, very good, or excellent), and results on the modified 36-item Short-Form Health Survey (SF-36). All efficacy measures were analyzed on an intent-to-treat basis. Tolerability was evaluated based on adverse events reported spontaneously or elicited by the in vestigators using nonsuggestive questioning, as well as on the number of patients discontinuing treatment because of adverse events.

RESULTS

The study enrolled 147 patients (75 HC/IB, 72 OX/AC). The most common cause of low back pain was muscular/ligamentous injury (97/147; 66.0%), followed by degenerative disk disease (27/147; 18.4%). At baseline, 80 patients (54.4%) reported experiencing moderate pain, and 67 patients (45.6%) reported experiencing severe pain. There were no significant differences between HC/IB and OX/AC with regard to mean ( +/- SD) daily pain relief scores (2.40 +/- 1.06 vs 2.50 +/- 1.01, respectively), mean daily number of tablets of study medication (1.80 +/- 1.70 vs 2.20 +/- 1.60), mean daily number of doses of study medication (1.80 +/- 1.65 vs 2.10 +/- 1.58), mean daily number of tablets of supplemental analgesic medication (0.60 +/- 1.13 vs 0.50 +/- 0.99), mean daily number of doses of supplemental analgesic medication (0.60 +/- 1.07 vs 0.50 +/- 0.90), global evaluations, or mean scores on the modified SF-36. In addition, there were no significant differences in the proportion of patients experiencing adverse events with HC/IB (47; 62.7%) and OX/AC (45; 62.5%). Adverse events were consistent with those generally associated with the component analgesics and predominantly involved the central nervous system and gastrointestinal system.

CONCLUSIONS

The results of this study suggest that HC/IB and OX/AC are similarly effective and tolerable in relieving moderate or severe acute low back pain. Additional controlled longitudinal trials are necessary to evaluate the clinical utility of HC/IB in treating acute low back pain.

Extraction of near-field fluorescence from composite signals to provide high resolution images of glial cells

The subdiffraction optical resolution that can be achieved using near-field optical microscopy has the potential to permit new approaches and insights into subcellular function and molecular dynamics. Despite the potential of this technology, it has been difficult to apply to cellular samples. One significant problem is that sample thickness causes the optical information to be comprised of a composite signal containing both near- and far-field fluorescence. To overcome this issue we have developed an approach in which a near-field optical fiber is translated toward the cell surface. The increase in fluorescence intensity during z-translation contains two components: a far-field fluorescence signal when the tip of the fiber is distant from the labeled cell, and combined near- and far-field fluorescence when the tip interacts with the cell surface. By fitting a regression curve to the far-field fluorescence intensity as the illumination aperture approaches the cell, it is possible to isolate near-field from far-field fluorescent signals. We demonstrate the ability to resolve actin filaments in chemically fixed, hydrated glial cells. A comparison of composite fluorescence signals with extracted near-field fluorescence demonstrates that this approach significantly increases the ability to detect subcellular structures at subdiffraction resolution.

Dose-response effect of combination hydrocodone with ibuprofen in patients with moderate to severe postoperative pain

OBJECTIVE

The objective of this study was to demonstrate a dose-response effect with 1- and 2-tablet doses of combination hydrocodone 7.5 mg with ibuprofen 200 mg and placebo in patients with moderate to severe postoperative abdominal or gynecologic pain.

BACKGROUND

Hydrocodone 7.5 mg with ibuprofen 200 mg is the only approved fixed-dose combination analgesic containing an opioid and ibuprofen. Previous studies with this combination have demonstrated that the components have an additive analgesic effect as well as efficacy compared with other fixed-dose combination analgesics.

METHODS

This randomized, parallel-group, double-blind, single-dose, placebo-controlled study compared 1 tablet of hydrocodone 7.5 mg with ibuprofen 200 mg (n = 60), 2 tablets of hydrocodone 7.5 mg with ibuprofen 200 mg (n = 60), and placebo (n = 60) in patients with moderate or severe pain after abdominal or gynecologic surgery. Analgesia was evaluated over 8 hours.

RESULTS

Mean pain relief (PR) scores were significantly greater for the 2-tablet dose than for the 1-tablet dose at 80 (P = 0.027) and 100 (P = 0.017) minutes and at 2 (P = 0.013), 2.5 (P = 0.012), 3 (P = 0.006), 4 (P = 0.029), 5 (P = 0.002), 6 (P = 0.032), 7 (P = 0.036), and 8 (P = 0.01) hours. Mean pain intensity difference scores were significantly greater for the 2-tablet dose than for the 1-tablet dose at 80 (P = 0.013) and 100 (P = 0.007) minutes and at 2 (P = 0.003), 2.5 (P = 0.002), 3 (P = 0.002), 4 (P = 0.009), 5 (P < 0.001), 6 (P = 0.004), 7 (P = 0.009), and 8 (P = 0.001) hours. Mean total PR scores were significantly greater for the 2-tablet dose than for the 1-tablet dose for all measured time intervals (0 to 3 hours, P = 0.01; 0 to 4 hours, P = 0.006; 0 to 6 hours, P = 0.003; 0 to 8 hours, P = 0.003). Mean sum of pain intensity differences was significantly greater for the 2-tablet dose than for the 1-tablet dose for all measured time intervals (0 to 3 hours, P = 0.004; 0 to 4 hours, P < 0.001; 0 to 6 hours, P < 0.001; 0 to 8 hours, P < 0.001). Mean peak PR score and median time-to-remedication were significantly greater for the 2-tablet dose than for the 1-tablet dose (P < 0.029 and P = 0.017, respectively). Both doses were superior to placebo. There were no significant differences in the number of patients experiencing adverse events between the 2-tablet dose (n = 6 [10.0%]), the 1-tablet dose (n = 4 [6.7%]), and placebo (n = 1 11.7%]). Adverse events were not serious, and none of the patients discontinued therapy because of side effects.

CONCLUSIONS

This study demonstrated that a 2-tablet dose of hydrocodone with ibuprofen provided significantly more analgesia than a 1-tablet dose (a positive dose-response effect) and that both doses were superior to placebo.

Combination hydrocodone and ibuprofen versus combination codeine and acetaminophen for the treatment of chronic pain

OBJECTIVE

The objective of this study was to compare the effectiveness of combination hydrocodone 7.5 mg and ibuprofen 200 mg with that of combination codeine 30 mg and acetaminophen 300 mg for the treatment of chronic pain.

BACKGROUND

Hydrocodone 7.5 mg with ibuprofen 200 mg is the only approved fixed-dose combination analgesic containing an opioid and ibuprofen.

METHODS

In this randomized, parallel-group, double-blind, repeated-dose, active-comparator, 4-week, multicenter study, 469 patients were randomly assigned to receive a 1-tablet (n = 156) or 2-tablet (n = 153) dose of combination hydrocodone 7.5 mg and ibuprofen 200 mg (HI1 and HI2, respectively) or a 2-tablet dose of combination codeine 30 mg and acetaminophen 300 mg (CA, n = 160), the active comparator, every 6 to 8 hours as needed for pain. Efficacy was measured through pain relief scores, number of daily doses of study medication, number of daily doses of supplemental analgesics, number of patients who discontinued therapy due to an unsatisfactory analgesic response, and global assessment scores.

RESULTS

Of the 469 patients, 255 (54.4%) were female and 214 (45.6%) were male. The mean age was 51.1 years. Types of chronic pain included back (214; 45.6%), arthritic (145; 30.9%), other musculoskeletal (65; 13.9%), cancer (6; 1.3%), diabetic neuropathic (3; 0.6%), postherpetic neuralgic (5; 1.1%), other neurologic (21; 4.5%), and other unclassified chronic pain (10; 2.1%). During the 48 hours prior to the study, 351 (74.8%) patients had been treated with opioid or opioid-nonopioid combination analgesics. The overall mean daily pain relief score was significantly greater in the HI2 group (2.25+/-0.89) than in the HI1 group (1.98+/-0.87) (P = 0.003) or the CA group (1.85+/-0.96) (P < 0.001). The overall mean number of daily doses of study medication was significantly less in the HI2 group (2.94+/-0.99) than in the HI1 group (3.23+/-0.76) (P = 0.036) or the CA group (3.26+/-0.75) (P = 0.014). The overall mean number of daily doses of supplemental analgesics was significantly less in the HI2 group (0.24+/-0.49) than in the HI1 group (0.34+/-0.58) (P = 0.021) or CA group (0.49+/-0.85) (P = 0.010). The number of patients who discontinued treatment due to an unsatisfactory analgesic response was significantly less in the HI2 group (2; 1.3%) than in the CA group (12; 7.5%) (P = 0.008). HI2 was more effective than HI1 and CA as measured by pain relief scores for week 1 (P < 0.001 vs HI1 and CA), week 2 (P < 0.001 vs HI1 and CA), and week 3 (P = 0.008 vs HI1 and P < 0.001 vs CA); daily doses of study medication for week 1 (P = 0.019 vs HI1 and P = 0.011 vs CA); daily doses of supplemental analgesics for week 1 (P = 0.010 vs HI1 and CA); and global assessment scores for week 1 (P = 0.018 vs HI1 and P < 0.001 vs CA), week 2 (P = 0.005 vs HI1 and P < 0.001 vs CA), and week 4 (P = 0.013 vs HI1 and P = 0.023 vs CA). There were no significant differences between HI1 and CA in any efficacy variable. There were no significant differences in the number of patients experiencing adverse events in the HI2 (127; 83%), HI1 (124; 79.5%), and CA (129; 80.6%) groups. However, the mean number of patients who discontinued treatment due to adverse events was significantly greater in the HI2 group (40; 26.1%) than in the HI1 group (23; 14.7%) (P = 0.013).

CONCLUSIONS

The results of this study suggest that 2-tablet doses of combination hydrocodone 7.5 mg and ibuprofen 200 mg may be more effective than either 1-tablet doses of this combination or 2-tablet doses of combination codeine 30 mg and acetaminophen 300 mg. Moreover, 1-tablet doses of combination hydrocodone 7.5 mg and ibuprofen 200 mg may be as effective as 2-tablet doses of combination codeine 30 mg and acetaminophen 300 mg.

Combination hydrocodone and ibuprofen versus combination oxycodone and acetaminophen in the treatment of postoperative obstetric or gynecologic pain

OBJECTIVE

The objective of this study was to compare the effectiveness of combination hydrocodone and ibuprofen with that of combination oxycodone and acetaminophen in the treatment of moderate to severe postoperative obstetric or gynecologic pain.

BACKGROUND

Hydrocodone 7.5 mg with ibuprofen 200 mg is the only approved fixed-dose combination analgesic containing an opioid and ibuprofen.

METHODS

This randomized, double-blind, parallel-group, single-dose, active-comparator, placebo-controlled study compared the effects of a 2-tablet dose of hydrocodone 7.5 mg and ibuprofen 200 mg with those of a 2-tablet dose of oxycodone 5 mg and acetaminophen 325 mg and placebo. Analgesia was assessed over 8 hours.

RESULTS

Mean pain relief (PR) scores were similar for the hydrocodone with ibuprofen and oxycodone with acetaminophen groups (n = 61 and 59, respectively) at 0.5, 1, 1.5, 2, 2.5, 3, 4, and 7 hours and significantly greater for the hydrocodone with ibuprofen group at 5, 6, and 8 hours (P < or = 0.05). Mean pain intensity difference (PID) scores were similar for hydrocodone with ibuprofen and oxycodone with acetaminophen at 0.5, 1, 1.5, 2, 2.5, 3, and 4 hours and significantly greater for hydrocodone with ibuprofen at 5, 6, 7, and 8 hours (P < or = 0.05). Total PR scores were similar for hydrocodone with ibuprofen and oxycodone with acetaminophen for the 0- to 3- and 0- to 4-hour intervals and significantly greater for hydrocodone with ibuprofen for the 0- to 6- and 0- to 8-hour intervals (P < 0.05). The sum of the PID scores was similar for hydrocodone with ibuprofen and oxycodone with acetaminophen for the 0- to 3-, 0- to 4-, 0- to 6-, and 0- to 8-hour intervals. The median estimated time to onset of analgesia, mean peak PR score, median time to remedication, and mean global assessment score were similar for hydrocodone with ibuprofen and oxycodone with acetaminophen. Assay sensitivity was demonstrated by the presence of statistically significant differences between both active treatments and placebo (n = 60). The number of patients experiencing adverse events was similar for each of the 3 groups (11 [18.0%], hydrocodone with ibuprofen; 7 [11.9%], oxycodone with acetaminophen; and 6 [10.0%], placebo).

CONCLUSIONS

In this study, a 2-tablet dose of combination hydrocodone 7.5 mg and ibuprofen 200 mg was as effective as a 2-tablet dose of combination oxycodone 5 mg and acetaminophen 325 mg in the treatment of moderate to severe postoperative obstetric or gynecologic pain. Both treatments were superior to placebo. The results of this study suggest that the combination of hydrocodone 7.5 mg and ibuprofen 200 mg may offer prescribers an additional option in combination pain therapy.

SNARE protein-dependent glutamate release from astrocytes

We investigated the cellular mechanisms underlying the Ca(2+)-dependent release of glutamate from cultured astrocytes isolated from rat hippocampus. Using Ca(2+) imaging and electrophysiological techniques, we analyzed the effects of disrupting astrocytic vesicle proteins on the ability of astrocytes to release glutamate and to cause neuronal electrophysiological responses, i.e., a slow inward current (SIC) and/or an increase in the frequency of miniature synaptic currents. We found that the Ca(2+)-dependent glutamate release from astrocytes is not caused by the reverse operation of glutamate transporters, because the astrocyte-induced glutamate-mediated responses in neurons were affected neither by inhibitors of glutamate transporters (beta-threo-hydroxyaspartate, dihydrokainate, and L-trans-pyrrolidine-2,4-dicarboxylate) nor by replacement of extracellular sodium with lithium. We show that Ca(2+)-dependent glutamate release from astrocytes requires an electrochemical gradient necessary for glutamate uptake in vesicles, because bafilomycin A(1), a vacuolar-type H(+)-ATPase inhibitor, reduced glutamate release from astrocytes. Injection of astrocytes with the light chain of the neurotoxin Botulinum B that selectively cleaves the vesicle-associated SNARE protein synaptobrevin inhibited the astrocyte-induced glutamate response in neurons. Therefore, the Ca(2+)-dependent glutamate release from astrocytes is a SNARE protein-dependent process that requires the presence of functional vesicle-associated proteins, suggesting that astrocytes store glutamate in vesicles and that it is released through an exocytotic pathway.

Subcellular distributions and excited-state processes of hypericin in neurons

The photodynamic drug, hypericin, is studied in fetal rat neurons using fluorescence microscopy. Hypericin has an extremely high affinity for the cell membrane and is found to a smaller extent in the nucleus. Fluorescent excitation of hypericin is shown to cause irreversible damage to the cell membranes of living neurons. Fixed cells were used to make ultrafast time-resolved measurements to avoid the deleterious effects of long-term exposure to intense light and room temperatures. To our knowledge, these are the first ultrafast time-resolved measurements of the fluorescence lifetime of hypericin in a subcellular environment. Nonexponential fluorescence decay is observed in hypericin in the neurons. This nonexponential decay is discussed in terms of other examples where nonexponential decay is induced in hypericin upon its binding to biomolecules. The nonradiative processes giving rise to the nonexponential hypericin decay are attributed to excited-state electron transfer, excited-state proton transfer or both.

Analgesic efficacy of a combination of hydrocodone with ibuprofen in postoperative pain

Two randomized, double-blind, parallel-group single-dose 2 x 2 factorial analgesic studies compared a single-dose or a 2-tablet dose of a combination of 7.5 mg hydrocodone bitartrate with 200 mg ibuprofen with each constituent alone and with a placebo in women with moderate or severe postoperative pain from abdominal or gynecologic surgery. A nurse-observer recorded patient reports of pain intensity and pain relief periodically for 8 hours. In both studies, the combination was significantly superior to placebo for sum of the pain intensity differences (SPID), total pain relief (TOTPAR), peak pain intensity difference (PID) and pain relief, global evaluation, and time to remedication. The combination was likewise significantly superior to both hydrocodone and ibuprofen for most of these summary measures of analgesia. In a factorial analysis, both the hydrocodone and ibuprofen effects were significant for most summary measures of analgesia, whereas results of the interaction contrast were consistent with the concept that the analgesic effect of the combination represents the additive analgesia of its 2 constituents.

Contact-dependent regulation of N-type calcium channel subunits during synaptogenesis

The developmental regulation of the N-type calcium channel during synaptogenesis was studied using cultured rat hippocampal neurons to elucidate the roles of extrinsic versus intrinsic cues in the expression and distribution of this channel. Prior to synapse formation, alpha1B and beta3 subunits of the N-type calcium channel were distributed diffusely throughout neurites, growth cones, and somata. As synaptogenesis proceeded, the subunit distributions became punctate and colocalized with the synaptic vesicle protein synaptotagmin. Isolated neurons were also examined to test for the requirement of extrinsic cues that control N-type calcium channel expression and distribution. These neurons expressed N-type calcium channel subunits, but their distributions remained diffuse. Functional omega-conotoxin GVIA-sensitive channels were expressed in isolated neurons, although the distribution of alpha1B subunits was diffuse. The distribution of the alpha1B subunit and synaptotagmin only became punctate when neuron-neuron contact was allowed. Thus, the expression of functional N-type calcium channels is the result of an intrinsic program while extrinsic regulatory cues mediated by neuron-neuron contact are required to control their distribution during synaptogenesis.

Calcium-independent activation of the secretory apparatus by ruthenium red in hippocampal neurons: a new tool to assess modulation of presynaptic function

The functional plasticity of the nervous system may result in part from the direct modulation of the effectiveness of the release machinery of synaptic terminals. To date, direct modulation of secretion in neurons has proven difficult to study because of the lack of a suitable tool to probe the release machinery independently of calcium influx. We report that the polyvalent cation ruthenium red (RR) directly evokes rapid and reversible calcium-independent quantal secretion in hippocampal neurons by binding to external sites on the presynaptic terminal membrane. This binding can be displaced by heparin and is not associated with ultrastructural damage to the synaptic terminals. The use of RR-evoked release as a tool has allowed us to detect a direct modulation of the secretory apparatus after activation of A1 adenosine receptors on hippocampal neurons.

Dynamic imaging of purified individual synaptic vesicles

The atomic force microscope (AFM) was used to directly image purified synaptic vesicles. Individual secretory vesicles (approximately 50 nm diameter) were resolved with the AFM when imaged either dry or in solution. Vesicles were observed repeatedly for periods of greater than 2 h. To ask whether the AFM can detect structural change of vesicles the osmolarity of the bathing medium was reduced from 330 to 110 mOsm. Hypo-osmotic treatment caused an expansion and flattening of the vesicles. Thus, using the AFM it is possible to resolve individual vesicles and follow changes in vesicular structure. This opens the possibility that the secretory event can be reconstituted and visualized in vitro in order to elucidate the roles of synaptic proteins in synaptic transmission.

FMRFamide modulation of secretory machinery underlying presynaptic inhibition of synaptic transmission requires a pertussis toxin-sensitive G-protein

The neuropeptide FMRFamide modulates synaptic transmission between identified neurons of the pond snail Helisoma trivolvis. FMRFamide causes a presynaptic inhibition of transmitter release by actions on ion channels and secretory machinery (Man-Son-Hing et al., 1989). The actions of FMRFamide on secretory machinery were studied using giant synapses that form between somata in culture. Using the calcium cage DM-nitrophen, synchronized, calcium-clamped release of neurotransmitter was promoted by UV photolysis. A series of UV flashes (15 msec duration) repeatedly promoted the transient synchronized release of neurotransmitter. Addition of FMRFamide reduced the magnitude of these flash-evoked inhibitory postsynaptic currents. Under conditions of synchronized transmitter release, FMRFamide modulates the secretory responsiveness to internal calcium. The release of neurotransmitter at somasoma synapses was determined to be quantal in nature. To test for the involvement of G-proteins in mediating the effects of FMRFamide on secretory machinery, the modulation of the frequency of miniature inhibitory postsynaptic currents (MIPSCs) was examined. Addition of FMRFamide reduced the frequency of MIPSCs without affecting intracellular free calcium measured with fura-2. Injection of a nonhydrolyzable analog of GTP, GTP gamma S, mimicked the effect of FMRFamide and reduced MIPSC frequency. Preinjection of the presynaptic soma with the A-protomer of pertussis toxin (PTX) prevented FMRFamide from reducing MIPSC frequency. Thus, a PTX-sensitive G-protein mediates the action of FMRFamide on secretory machinery. Similarly, preinjection of the presynaptic soma with PTX prevented FMRFamide from reducing the magnitude of action potential-evoked IPSC. Dose-response curves for the actions of FMRFamide on secretory machinery and calcium current were constructed and demonstrated that secretory machinery can be modulated at concentrations of FMRFamide (less than or equal to 10(-7) M) that do not affect calcium current magnitude. At a concentration of 10(-7) M FMRFamide, action potential-evoked synaptic transmission was reduced. Thus, synaptic transmission can be regulated by the modulation of secretory machinery, without a requirement for the modulation of ion channels.

Target contact regulates the calcium responsiveness of the secretory machinery during synaptogenesis

Neuron B19 of Helisoma is selective in synaptogenesis. Presynaptic mechanisms underlying this selectivity were tested. Acetylcholine-sensitive assay cells were micromanipulated into contact with B19 somata to assess its secretory state. Prior to appropriate muscle target contact, spontaneous synaptic currents were detected; however, action potential-evoked release of neurotransmitter was detected only following hours of muscle contact. Photolysis of a calcium cage, DM-nitrophen, accelerated the frequency of synaptic currents in muscle-contacted, but not novel neuron-contacted, B19 somata. These studies demonstrate that contact with appropriate target muscle enhances the responsiveness of this neuron's secretory machinery to internal calcium levels, thereby imparting the presynaptic cell with the ability to couple action potentials with neurotransmitter release.

Target-dependent induction of secretory capabilities in an identified motoneuron during synaptogenesis

Cholinergic neurons isolated from the buccal ganglia of Helisoma were plated into cell culture with a variety of defined target cells to study the specificity of synaptogenesis. Motoneuron B19 selectively formed chemical connections with single dissociated muscle fibers derived from its appropriate target, the supralateral radular tensor (SLT) muscle. B19 did not form such connections with novel neuronal targets. In contrast to neuron B19, cholinergic neuron B5 nonselectively formed chemical connections with novel muscle and neuronal targets. Target cells were micromanipulated into contact with presynaptic neurons to examine the latent period until the onset of functional synaptic transmission. Neuron B5 formed chemical connections within the first minutes of contact with ACh-sensitive neurons and muscle while B19 required sustained periods of muscle-specific contact to induce the acquisition of a functional excitation-secretion coupling mechanism. These different latent periods from the onset of target contact suggest that neuron B5 acquires presynaptic secretory function before target contact, while B19 must receive a specific signal(s) from its appropriate target to induce the transformation of its terminal into a secretory state.

Clinical evaluation and prerelease management of American river otters in the second year of a reintroduction study

In the first year (1984) of a reintroduction study, 10 American river otters (Lutra canadensis) from Louisiana were transported to Oklahoma, held for 5 days for clinical evaluation, surgical implantation with intra-abdominal radiotelemetry devices, and then released in Oklahoma. Four of 10 otters released died within 32 days. Clinical evaluation indicated that respiratory tract disease, bacterial and parasitic infections, and inanition may have contributed to the death of these otters. In the second year (1985) of the study, an exotic feline diet was fed, and the holding period for 10 otters was increased to provide time for evaluation and treatment before surgery, postsurgical acclimation to Oklahoma, and reevaluation before release. Although the initial clinical findings on otters in the second year were similar to those found in the first year, otter body weights increased, and the prevalence and severity of clinical abnormalities decreased with treatment during the second-year holding period. Three of 10 second-year otters died during the holding period, and contributing causes of death were determined to be: trauma (hepatic hematoma), inanition, renal disease, pneumonia, salmonellosis (Salmonella anatum), and a retropharyngeal abscess (Klebsiella pneumoniae). Seven healthy otters were reintroduced into Oklahoma in 1985, and postrelease deaths were not experienced.