Therapeutic hFIX Activity Achieved after Single AAV5-hFIX Treatment in Hemophilia B Patients and NHPs with Pre-existing Anti-AAV5 NABs.

Currently, individuals with pre-existing neutralizing antibodies (NABs) against adeno-associated virus (AAV) above titer of 5 are excluded from systemic AAV-based clinical trials. In this study we explored the impact of pre-existing anti-AAV5 NABs on the efficacy of AAV5-based gene therapy. AMT-060 (AAV5-human FIX) was evaluated in 10 adults with hemophilia B who tested negative for pre-existing anti-AAV5 NABs using a GFP-based assay. In this study, using a more sensitive luciferase-based assay, we show that 3 of those 10 patients tested positive for anti-AAV5 NABs. However, no relationship was observed between the presence of pre-treatment anti-AAV5 NABs and the therapeutic efficacy of AMT-060. Further studies in non-human primates (NHPs) showed that AAV5 transduction efficacy was similar following AMT-060 treatment, irrespective of the pre-existing anti-AAV5 NABs titers. We show that therapeutic efficacy of AAV5-mediated gene therapy was achieved in humans with pre-existing anti-AAV5 NABs titers up to 340. Whereas in NHPs circulating human factor IX (hFIX) protein was achieved, at a level therapeutic in humans, with pre-existing anti-AAV5 NABs up to 1030. Based on those results, no patients were excluded from the AMT-061 (AAV5-hFIX-Padua) phase IIb clinical trial (n = 3). All three subjects presented pre-existing anti-AAV5 NABs, yet had therapeutic hFIX activity after AMT-061 administration.

Prospective comparative cohort study evaluating incompetent great saphenous vein closure using radiofrequency-powered segmental ablation or 1470-nm endovenous laser ablation with radial-tip fibers (Varico 2 study).

BACKGROUND: Endovenous laser ablation (EVLA) and radiofrequency-powered segmental ablation (RPSA) of the incompetent great saphenous vein (GSV) are both known for their excellent technical and clinical outcomes for the treatment of varicose veins. RPSA has reduced postprocedural pain and morbidity with shorter recovery time for the patient compared with EVLA using bare-tip fibers. However, new-generation EVLA devices with less traumatic radial-tip fibers (RTFs) operating at longer wavelengths up to 1470 nm also reduce postprocedural pain. The objective of this study was to compare long-term effectiveness of GSV thermal ablation and postprocedural recovery using RPSA or 1470-nm EVLA with RTF (EVLA-RTF). METHODS: In a comparative prospective monthly altering-treatment cohort study of 311 patients (346 treated legs), each leg with incompetence of the GSV was treated with either RPSA (158 patients, 175 legs) or EVLA-RTF (153 patients, 171 legs). The primary outcome was anatomic occlusion of the GSV, assessed at 12, 24, 36, 48, and 60 months using Kaplan-Meier statistics and compared using the log-rank test. Secondary outcomes included freedom of varicose vein recurrence, clinical success measured by Venous Clinical Severity Score (VCSS), disease-specific quality of life determined using the Aberdeen Varicose Vein Questionnaire (AVVQ), postoperative pain scores, and time to return to work. RESULTS: The total primary obliteration rate after 36 and 60 months was 96.2% with RPSA and 96.7% with EVLA-RTF (P = .81). Freedom of symptomatic anterior accessory vein recurrence after 5 years was 85% after RPSA and 87% after EVLA-RTF (P = .50). VCSS and AVVQ score presented similar and durable improvements in both groups between 6 weeks and 60 months. There was no difference in postoperative pain scores after both treatments during the first 14 days (mean visual analog scale score, 0.54-2.19). The median time for return to work was 1 day after both treatments. No severe adverse events were observed. CONCLUSIONS: RPSA and EVLA-RTF have similarly high GSV obliteration rates in the long term, and the treatments are equally effective clinically. Both treatments are associated with similar minimal postprocedural pain scores and short recovery times.

Gene therapy with adeno-associated virus vector 5-human factor IX in adults with hemophilia B.

Gene therapy for hemophilia B aims to ameliorate bleeding risk and provide endogenous factor IX (FIX) activity/synthesis through a single treatment, eliminating the requirement for FIX concentrate. AMT-060 combines an adeno-associated virus-5 (AAV5) vector with a liver-specific promoter driving expression of a codon-optimized wild-type human FIX gene. This multinational, open-label study included 10 adults with hemophilia B (FIX ≤2% of normal) and severe-bleeding phenotype. No participants tested positive for AAV5-neutralizing antibodies using a green-fluorescent protein-based assay, and all 10 were enrolled. A single dose of 5 × 1012 or 2 × 1013 genome copies of AMT-060/kilogram was administered to 5 participants each. In the low-dose cohort, mean endogenous FIX activity increased to 4.4 IU/dL. Annualized FIX use was reduced by 81%, and mean annualized spontaneous bleeding rate (ASBR) decreased from 9.8% to 4.6% (53%). In the higher-dose cohort, mean FIX activity increased to 6.9 IU/dL. Annualized FIX use decreased by 73%, and mean ASBR declined from 3.0 to 0.9 (70%). There was no reduction in traumatic bleeds. FIX activity was stable in both cohorts, and 8 of 9 participants receiving FIX at study entry stopped prophylaxis. Limited, asymptomatic, and transient alanine aminotransferase elevations in the low-dose (n = 1) and higher-dose (n = 2) cohorts were treated with prednisolone. No decrease in FIX activity or capsid-specific T-cell responses were detected during transaminase elevations. A single infusion of AMT-060 had a positive safety profile and resulted in stable and clinically important increases in FIX activity, a marked reduction in spontaneous bleeds and FIX concentrate use, without detectable cellular immune responses against capsids. This trial was registered at www.clinicaltrials.gov as #NCT02396342; EudraCT #2013-005579-42.

Single-dose TB-402 or rivaroxaban for the prevention of venous thromboembolism after total hip replacement. A randomised, controlled trial.

TB-402 is a long-acting monoclonal antibody that partially inhibits factor VIII. A single administration of TB-402 was effective and well-tolerated for the prevention of venous thromboembolism (VTE) after total knee replacement. In this study, the efficacy and safety of a single administration of TB-402 for the extended prophylaxis of VTE after total hip replacement (THR) was investigated. This was a phase II, randomised, active-controlled, double-blind study that included patients undergoing elective THR surgery. Patients were randomised to TB-402 25 mg or TB-402 50 mg, administered as a single intravenous administration 2-4 hours postoperatively, or to rivaroxaban 10 mg once daily for 35 days. The primary efficacy outcome was total VTE defined as symptomatic VTE and asymptomatic deep-vein thrombosis (DVT) detected by bilateral venography at day 35. The principal safety outcome was the incidence of major bleeding and clinically relevant non-major bleeding until day 35. Total VTE was similar in all groups: 5.3% (95%CI 2.9-9.6), 5.2% (95%CI 2.8-9.3) and 4.7% (95%CI 2.5-8.7) for TB-402 25 mg, TB-402 50 mg and rivaroxaban, respectively. All were asymptomatic DVTs. Major or clinically relevant non-major bleedings were observed in 5.8% (95%CI 3.3-9.9), 7.2% (95%CI 4.4-11.6) and 1.4% (95%CI 0.5-4.2) for TB-402 25 mg, TB-402 50 mg and rivaroxaban, respectively. In conclusion, TB-402, administered as a single postoperative dose, had a similar efficacy compared to rivaroxaban for the prevention of VTE after THR. The incidence of major and clinically relevant non-major bleeding was higher in the TB-402 groups than in the rivaroxaban group.

Long-term risk of vascular events after peripheral bypass surgery. A cohort study.

Patients with peripheral arterial disease (PAD) are at high risk of major ischaemic events. Long-term data of all major ischaemic events in PAD patients are scarce and outdated, especially for patients with severe PAD requiring bypass surgery. Our objective was to define their long-term prognosis and develop a prediction model which quantifies this risk up to a decade after surgery. We conducted a retrospective cohort study in patients from the Dutch Bypass Oral anticoagulants or Aspirin (BOA) Study; a multicentre randomised trial comparing oral anticoagulants with aspirin after infrainguinal bypass surgery. The primary outcome was the composite event of non-fatal myocardial infarction, non-fatal ischaemic stroke, major amputation, and vascular death. Cumulative risks were assessed by Kaplan-Meier analysis and independent determinants by multivariable Cox regression models. From 1995 until 2009, 482 patients were followed for a median period of 7.8 years. Follow-up was complete in 94%. Overall 60% of patients experienced a primary outcome event, of which the majority was a vascular death (30%), followed by major amputations (12%). The primary cause of vascular death was a cardiovascular event (29%), whereas the minority was due to complications directly related to PAD (6%). Within five years after bypass surgery vascular death occurred in about a quarter of patients and within 10 years in nearly half of patients. This was double the rate as for non-vascular death. The primary outcome event occurred in over a third and over half of patients in 5 and 10 years after bypass surgery, respectively. From four independent determinants for the primary outcome event: age, diabetes, critical limb ischaemia, and prior vascular interventions, we developed a risk chart, which systematically classifies the 10-year risks of the primary outcome event, ranging from 25% to 85%. This study provided a detailed insight in the course of PAD long after peripheral bypass surgery and enables individual risk assessment of major fatal and non-fatal ischaemic events by means of cumulative incidences and a risk chart.

The quality of life in patients after peripheral bypass surgery deteriorates at long-term follow-up.

OBJECTIVE: We aimed to study the long-term development of health-related quality of life (HR-QoL) in patients with peripheral arterial disease after they underwent peripheral bypass surgery and to evaluate the influence of adverse vascular events that occurred during follow-up. METHODS: We compared current HR-QoL scores with previous measurements in patients who participated in the Dutch Bypass and Oral Anticoagulants or Aspirin (BOA) Study between 1995 and 1998 after they underwent infrainguinal bypass surgery. Patients from six centers that contributed most to the Dutch BOA Study (n = 482) were followed up retrospectively from 1995 up to 2009. RESULTS: At a mean follow-up of 11 years since BOA randomization, 165 of the 482 patients were alive of whom 123 (75%) completed the EQ-5D and RAND-36 questionnaires. Fifty-three patients completed the questionnaires three times: at BOA entry, at BOA close-out, and at BOA long-term follow-up. In these patients the HR-QoL scores decreased over time, especially for the physical health dimension. In comparison with the general population, matched for age and gender, the HR-QoL scores at both BOA entry and long-term follow-up were substantially lower, even if the patient's graft was patent and no other vascular events had occurred. The occurrence of an adverse vascular event worsened the physical health state further. CONCLUSIONS: The physical HR-QoL in patients with peripheral arterial disease (PAD) after peripheral bypass surgery was highly impaired, independent of graft patency, and deteriorated further over time. An adverse vascular event worsened the physical health state and underlined the importance of atherosclerotic risk management as well as stimulation of physical activity in patients with peripheral arterial disease to preserve HR-QoL.

Bleeding increases the risk of ischemic events in patients with peripheral arterial disease.

BACKGROUND: Patients with peripheral arterial disease are at high risk of ischemic events and therefore are treated with antithrombotics. In patients with coronary artery disease or cerebrovascular disease, bleeding is related to the subsequent occurrence of ischemic events. Our objective was to assess whether this is also the case in patients with peripheral arterial disease. METHODS AND RESULTS: All patients from the Dutch Bypass and Oral Anticoagulants or Aspirin (BOA) Study, a multicenter randomized trial comparing oral anticoagulants with aspirin after infrainguinal bypass surgery, were included. The primary outcome event was the composite of nonfatal myocardial infarction, nonfatal ischemic stroke, major amputation, and cardiovascular death. To identify major bleeding as an independent predictor for ischemic events, crude and adjusted hazard ratios with 95% confidence intervals were calculated with multivariable Cox regression models. From 1995 until 1998, 2650 patients were included with 101 nonfatal major bleedings. During a mean follow-up of 14 months, the primary outcome event occurred in 218 patients; 22 events were preceded by a major bleeding. The mean time between major bleeding and the primary outcome event was 4 months. Major bleeding was associated with a 3-fold increased risk of subsequent ischemic events (crude hazard ratio, 3.0; 95% confidence interval, 1.9 to 4.6; adjusted hazard ratio, 3.0; 95% confidence interval, 1.9 to 4.7). CONCLUSIONS: In patients with peripheral arterial disease, as in patients with coronary artery disease or cerebrovascular disease, major bleeding was independently associated with major ischemic complications. Without compromising the benefits of antithrombotics, these findings call for caution relative to the risks of major bleeding.

Growth predictors and prognosis of small abdominal aortic aneurysms.

OBJECTIVE: Evidence regarding the influence of cardiovascular risk factors, comorbidities, and patient characteristics on the growth of small abdominal aortic aneurysms (AAA) is limited. We assessed, in an observational cohort study, rupture rates, risks of mortality, and the effects of cardiovascular risk factors and patient demographics on growth rates of small AAAs. METHODS: Between September 1996 and January 2005, 5057 patients with manifest arterial vascular disease or cardiovascular risk factors were included in the Second Manifestation of ARTerial disease (SMART) study. Measurements of the abdominal aortic diameter were performed in all patients. All patients with an initial AAA diameter between 30 and 55 mm were selected for this study. All AAA measurements during follow-up until August 2007 were collected. Multivariate regression analysis was performed to calculate the effects of demographic patient characteristics, initial AAA diameter, and cardiovascular risk factors on AAA growth. RESULTS: Included were 230 patients, with a mean age of 66 years and 90% were male. Seven AAA ruptures (six fatal) occurred in 755 patient years of follow-up (rupture rate 0.9% per patient-year). In 147 patients, AAA measurements were performed for a period of more than 6 months. The median follow-up time was 3.3 years (mean 4.0, range 0.5 to 11.1 years, standard deviation (SD) 2.5). Mean AAA diameter was 38.8 mm (SD 6.8) and mean expansion rate 2.5 mm/y. Patients using lipid-lowering drugs had a 1.2 mm/y (95% confidence interval [CI] -2.34 to -0.060 mm/y) lower AAA growth rate compared to nonusers of these drugs. Initial AAA diameter was associated with a 0.09 mm/y (95% CI 0.01 to 0.18 mm/y) higher growth rate per millimetre increase of the diameter. No other factors, including blood lipid values, were independently associated with AAA growth. CONCLUSIONS: Lipid-lowering drug treatment and initial AAA diameter appear to be independently associated with lower AAA growth rates. The risk of rupture of these small abdominal aortic aneurysms was low, which pleads for watchful waiting.

The rate of NSAID-induced endoscopic ulcers increases linearly but not exponentially with age: a pooled analysis of 12 randomised trials.

The risk of major ulcer complications on treatment with non-steroidal anti-inflammatory drugs (NSAIDs) is known to increase exponentially with age. However, in a pooled analysis of 12 trial arms, the incidence of endoscopic ulcers on treatment with NSAID was found to increase with age in a roughly linear fashion. Thus, it is concluded that increasing age is associated with both more frequent and more serious NSAID gastropathy.

Cardioprotective medication is associated with improved survival in patients with peripheral arterial disease.

OBJECTIVES: We sought to investigate the effect of cardiac medication on long-term mortality in patients with peripheral arterial disease (PAD). BACKGROUND: Peripheral arterial disease is associated with increased cardiovascular morbidity and mortality. Treatment guidelines recommend aggressive management of risk factors and lifestyle modifications. However, the potential benefit of cardiac medication in patients with PAD remains ill defined. METHODS: In this prospective observational cohort study, 2,420 consecutive patients (age, 64 +/- 11 years, 72% men) with PAD (ankle-brachial index < or =0.90) were screened for clinical risk factors and cardiac medication. Follow-up end point was death from any cause. Propensity scores for statins, beta-blockers, aspirin, angiotensin-converting enzyme (ACE) inhibitors, calcium channel blockers, diuretics, nitrates, coumarins, and digoxin were calculated. Cox regression models were used to analyze the relation between cardiac medication and long-term mortality. RESULTS: Medical history included diabetes mellitus in 436 patients (18%), hypercholesterolemia in 581 (24%), smoking in 837 (35%), hypertension in 1,162 (48%), coronary artery disease in 1,065 (44%), and a history of heart failure in 214 (9%). Mean ankle-brachial index was 0.58 (+/-0.18). During a median follow-up of eight years, 1,067 patients (44%) died. After adjustment for risk factors and propensity scores, statins (hazard ratio [HR] 0.46, 95% confidence interval [CI] 0.36 to 0.58), beta-blockers (HR 0.68, 95% CI 0.58 to 0.80), aspirins (HR 0.72, 95% CI 0.61 to 0.84), and ACE inhibitors (HR 0.80, 95% CI 0.69 to 0.94) were significantly associated with a reduced risk of long-term mortality. CONCLUSIONS: On the basis of this observational longitudinal study, statins, beta-blockers, aspirins, and ACE inhibitors are associated with a reduction in long-term mortality in patients with PAD.