Torbjörn Lundström

Prognostic factors for recurrence of venous thromboembolism (VTE) or bleeding during long-term secondary prevention of VTE with ximelagatran

The oral direct thrombin inhibitor ximelagatran (24 mg twice daily) has been shown to significantly reduce the incidence of recurrent venous thromboembolism (VTE) vs. placebo over 18 months, with no significant influence on bleeding (THRIVE III). The influence of potential prognostic factors on the risk of recurrent VTE or major and/or minor bleeding and their impact on ximelagatran treatment was evaluated in the THRIVE III study population. The effect of sex, age, body weight, renal function, malignancy, type of initial VTE event, and history of previous VTE events was investigated in the intention-to-treat population using Cox proportionate hazard modelling. Ximelagatran was administered to 612 patients and placebo to 611 patients. Within the placebo group, risk of recurrent VTE was higher among men than women (hazard ratio [HR]: 2.50,95% confidence interval [CI] 1.49,4.17), and in patients with one or more than one previous VTE event (HR: 1.73,95% CI 1.00, 2.99). There was a higher risk of bleeding among women than men in both the ximelagatran (HR: 1.49, 95% CI 1.06, 2.09) and placebo (HR: 1.48, 95% CI 1.01, 2.15) groups, and in placebo-treated patients with an initial pulmonary embolism (HR: 1.53, 95% CI 1.06,2.23) compared to those with initial deep vein thrombosis. There were no significant interactions between treatment effect and any of the potential prognostic factors. In conclusion, the superior efficacy of ximelagatran vs. placebo was maintained in all subgroups. Long-term use of oral ximelagatran, without coagulation monitoring or dose adjustment, should be feasible and well tolerated in a wide cross-section of patients for the secondary prevention of VTE.

Risk of recurrent venous thromboembolism or bleeding in relation to thrombophilic risk factors in patients receiving ximelagatran or placebo for long‐term secondary prevention of venous thromboembolism

The impact of prothrombotic abnormalities on the risk of recurrent venous thromboembolism (VTE) and bleeding in patients receiving long‐term anticoagulation remains unclear. This analysis evaluated the influence of potential prothrombotic risk factors (antithrombin, protein C, protein S, factor V Leiden mutation, prothrombin gene G20210A mutation, cardiolipin antibodies, number of risk factors) on the risk of recurrent VTE or bleeding during treatment with oral ximelagatran (24 mg twice daily) or placebo for 18 months [THRombin Inhibitor in Venous thromboEmbolism (THRIVE) III trial]. Of the 1223 patients in the intention‐to‐treat population, prothrombotic state was analysed in 559 patients receiving ximelagatran and 540 patients receiving placebo. It is possible that patients at a high risk of recurrent VTE were poorly represented in this analysis because of selection bias. Prothrombotic risk factors were reported in 41% of patients (8% had ≥2 factors). No significant interactions were found between ximelagatran treatment and potential prothrombotic risk factors for the risk of recurrent VTE or bleeding by Cox proportionate hazard modelling. There was no clear evidence for a higher risk of recurrent VTE or bleeding across subgroups according to the potential prothrombotic factors analysed in this study.

N-terminal proANF in acute atrial fibrillation: A biochemical marker of atrial pressures but not a predictor for conversion to sinus rhythm

BACKGROUND Atrial filling pressures are increased in acute atrial fibrillation, which stimulates the release of atrial natriuretic factor pro-hormone, proANF. METHODS In a randomized trial comparing digoxin with placebo in 216 patients, we investigated whether the baseline plasma level of N-terminal proANF is a predictor for conversion to sinus rhythm and the relation among N-terminal proANF, conversion to sinus rhythm, and changes in heart rate. RESULTS N-terminal proANF was increased at baseline and decreased significantly in patients converting to sinus rhythm, whereas it was mainly unchanged in nonconverters. N-terminal proANF was not a predictor of conversion to sinus rhythm. A relation was found between relative changes in heart rate and N-terminal proANF in nonconverters. CONCLUSION The level of N-terminal proANF does not predict conversion to sinus rhythm, which indicates that hemodynamics per se is not important. There is a correlation between relative changes in heart rate and N-terminal proANF in nonconverters.

Ximelagatran for the secondary prevention of venous thromboembolism: a complementary follow-up analysis of the THRIVE III study.

In the randomized, double-blind THRIVE III trial, the oral direct thrombin inhibitor ximelagatran (24 mg twice daily) significantly reduced the incidence of recurrent venous thromboembolism (VTE) versus placebo over 18 months or until premature study drug discontinuation. A complementary follow-up analysis (intention-to-treat) was conducted post-study to evaluate the cumulative risks of locally-confirmed recurrent VTE and death (Kaplan-Meier procedure) over the full 18-month study period, regardless of whether patients discontinued study drug prematurely. Hazard ratios (HRs) between treatments were estimated using Cox proportional hazard modeling. Of 612 and 611 patients receiving ximelagatran and placebo, respectively, 149 and 181 discontinued treatment prematurely. Of these discontinuations, further information could not be collected for 14 and 13 patients in the ximelagatran and placebo groups, respectively; among the remaining patients, four VTE events and four deaths occurred in the ximelagatran group, and one VTE event and five deaths occurred in the placebo group. The resulting cumulative risks of VTE (3.2% vs. 12.7%; HR 0.21; 95% confidence interval [CI], 0.12, 0.36; P < 0.0001) and pulmonary embolism (0.8% vs. 5.2%; HR 0.13; 95% CI 0.04, 0.36; P < 0.0001) were significantly lower in the ximelagatran than in the placebo group over 18 months. Death from any cause over 18 months occurred in 10 and 12 patients, respectively (HR 0.83;95% CI 0.36, 1.93; P = 0.7). This complementary follow-up analysis confirms the benefit of oral ximelagatran 24 mg twice daily, administered without coagulation monitoring or dose adjustment, for the long-term secondary prevention of VTE.

Assessment of omega-3 carboxylic acids in statin-treated patients with high levels of triglycerides and low levels of high-density lipoprotein cholesterol: Rationale and design of the STRENGTH trial

It is uncertain whether omega‐3 fatty acids are beneficial in statin‐treated patients. Epanova is a mix of omega‐3 free fatty acids, not requiring co‐ingestion with food, which can lower triglycerides by up to 31%. STRENGTH will examine whether Epanova 4 g daily reduces the rate of cardiovascular events in statin‐treated patients with hypertriglyceridemia and low levels of HDL‐C at high risk for developing cardiovascular events. STRENGTH is a randomized, double‐blind, placebo‐controlled trial. Patients had a triglyceride level ≥ 180 to <500 mg/dL and HDL‐C < 42 mg/dL (men) or < 47 mg/dL (women) in the presence of either (1) established atherosclerotic cardiovascular disease, (2) diabetes with one additional risk factor, or (3) were other high‐risk primary prevention patients, based on age and risk factor assessment. Patients should be treated with a statin, for >4 weeks, and have LDL‐C < 100 mg/dL, but were also eligible if LDL‐C was ≥100 mg/dL while on maximum tolerated statin therapy. The study will extend from October 30, 2014 to October 30, 2019. 13 086 patients were randomized to Epanova 4 g or placebo daily in addition to standard medical therapy. The primary efficacy outcome is time to first event of cardiovascular death, myocardial infarction, stroke, coronary revascularization or hospitalization for unstable angina. The trial will continue until 1600 patients reach the primary endpoint, with a median duration of therapy of 3 years. STRENGTH will determine whether Epanova 4 g daily will reduce cardiovascular events in statin‐treated high‐risk patients with hypertriglyceridemia and low HDL‐C levels.

Omega-3-carboxylic acids provide efficacious anti-inflammatory activity in models of crystal-mediated inflammation

This study assesses the efficacy and exposure–response relationship of omega-3-carboxylic acids (OM-3 CA) in models of crystal-based inflammation. Human THP-1 macrophages and primary peripheral blood mononuclear cells exposed to multiple inflammatory crystal types were used to determine the anti-inflammatory potential of omega-3 (OM-3) fatty acids in vitro. Anti-inflammatory effects of OM-3 CA in vivo were tested in rat monosodium urate (MSU) crystal air pouch and rat knee intra-articular MSU injection models. Acute treatment with the OM-3 fatty acid docosahexaenoic acid suppressed MSU-, cholesterol crystal-, and calcium pyrophosphate crystal-mediated interleukin-1β (IL-1β) production in vitro. In vivo, OM-3 CA dose-dependently reduced crystal-mediated cell migration, exudate volume, and levels of IL-1β and prostaglandin E2. Following intra-articular injection of MSU, treatment with OM-3-CA (1 mL/kg) and indomethacin (1 mg/kg) resulted in similar mean reductions in pain (23% and 41%, respectively) and swelling (58% and 50%, respectively), compared with controls. Additionally, in complex formulations of OM-3 fatty acids, high levels of palmitic acid could reduce the in vivo effect on crystal-mediated IL-1β elevation. OM-3 CA has a broadly efficacious anti-inflammatory effect with a strong exposure–response relationship that could be beneficial in prevention and treatment of crystal arthritis, with potential applications in other IL-1β-mediated diseases.

Safety, Tolerability, and Pharmacokinetics of Single and Multiple Oral Doses of an Omega-3-Carboxylic Acid Formulation in Healthy Male Japanese Subjects: A Phase 1 Single-Blind, Randomized, Placebo-Controlled Trial

OM3‐CA (omega‐3‐carboxylic acids) is a complex mixture of omega‐3 carboxylic acids, particularly eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), which is approved in the United States for the treatment of hypertriglyceridemia. As part of its clinical development in Japan, we performed a phase 1 study to investigate the safety, tolerability, and pharmacokinetics after single and multiple doses of OM3‐CA in healthy male Japanese subjects. Eighteen Japanese subjects were allocated to receive 2 or 4 g/day OM3‐CA, or placebo (n = 6 per group). In addition, 6 white subjects received 4 g/day OM3‐CA. The primary objective was to determine the safety and tolerability of OM3‐CA. Plasma concentrations of EPA and DHA were adjusted for baseline values for pharmacokinetic analysis. Overall, OM3‐CA was well tolerated in healthy Japanese subjects. Two Japanese subjects in each group and 5 white subjects experienced adverse events (AEs). Alanine aminotransferase increase was the most common AE in Japanese subjects, also seen with placebo, and diarrhea was the most common AE in white subjects. The maximum plasma concentrations of EPA and DHA were observed 5–6 hours postdose. The pharmacokinetic profiles of EPA and DHA after administration of OM3‐CA were comparable between Japanese and white subjects.

Effects of Food on the Pharmacokinetics of Omega-3-Carboxylic Acids in Healthy Japanese Male Subjects: A Phase I, Randomized, Open-label, Three-period, Crossover Trial

Aims: Omega-3-carboxylic acids (OM3-CA) contain omega-3 free fatty acids, such as eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), as carboxylic acids. Food intake is known to affect the bioavailability of ethyl ester fatty acid formulations. We conducted a phase I study to investigate the effects of the timing of OM3-CA administration relative to food intake on the pharmacokinetics of EPA and DHA. Methods: In this randomized, open-label, three-period crossover study, Japanese healthy male subjects were administered 4 × 1 g OM3-CA capsules with continued fasting, before a meal, or after a meal. All subjects fasted for ≥ 10 h prior to drug/meal administration. The primary objective was to examine the effect of meal timing on the pharmacokinetics of EPA and DHA after OM3-CA administration. The secondary objectives were to examine the safety and tolerability of OM3-CA. Results: A total of 42 Japanese subjects was enrolled in the study. The baseline-adjusted maximum concentration and area under the concentration–time curve from 0 to 72 h for EPA, DHA, and EPA + DHA were lower in the fasting and before meal conditions than in the after meal condition. The maximum total EPA, total DHA, and total EPA + DHA concentrations were reached later when administered in fasting conditions than in fed conditions, indicating slower absorption in fasting conditions. Diarrhea was reported by five, six, and no subjects in the fasting, before meal, and after meal conditions, respectively. Conclusions: The timing of OM3-CA administration relative to food intake influences the systemic bioavailability of EPA and DHA in healthy Japanese male subjects. Trial registration: NCT02372344