To compare the efficacy of treatment with two different levels of intermittent negative pressure (INP), applied to the lower limb, on self-reported spasticity and pain in patients with multiple sclerosis (MS). A randomized, two-arm multicenter trial enrolled patients with spasticity in the leg ≥ 4 on the numeric rating scale (NRS). Patients were randomized to treatment with −10 mmHg INP (low-dose group [LDG]) or −40 mmHg INP (high-dose group [HDG]) on the most affected leg, using the FlowOx 2.0 device (Otivio AS, Oslo, Norway). The device applies alternating cycles of 10 s of negative pressure and 7 s of ambient pressure via a sealed pressure chamber around the lower leg, for 1 h daily for 4 weeks. There was no difference in the change in NRS spasticity and pain score between the two groups after 4 weeks (estimated treatment effect 0.72; 95
Summary: Background: Intermittent negative pressure is an emerging treatment for lower limb vascular disease but the specific physiological effects, particularly upon large artery haemodynamics are unclear. This study examined the influence of intermittent negative pressure upon popliteal artery shear rate during both supine and sitting postures. Participants and methods: Eleven healthy participants (5 female; age: 28.3 ± 5.8 y; weight: 69.6 ± 9.8 kg, height: 1.75 ± 0.07 m) received intermittent negative pressure (–37 mmHg; 9.5-sec on, 7.5-sec off), upon the lower leg during both supine and sitting postures. Popliteal artery blood flow and shear rate were recorded (duplex ultrasound), accompanied by heart rate (3-lead ECG) and blood pressure (volume clamp method). Results: Compared to sitting, a supine posture led to greater mean shear rate during baseline (supine: 21[9]; sitting: 17[13] sec−1; all median [IQR]) and negative pressure phases (supine: 24[15]; sitting: 17[14] sec−1; both p<0.05). While supine, negative pressure raised mean shear rate above baseline levels (p<0.05) and reduced it upon return to atmospheric pressure (p < 0.05). In sitting, mean shear rate only differed from baseline at the points of peak and minimum shear (peak:18[17]; minimum: 10[9] sec−1; both p<0.05). Shear pattern (oscillatory shear index) showed changes from baseline during both postures (p<0.05), but was not different between postures. Conclusions: Intermittent negative pressure influenced lower limb popliteal artery shear rate during both the supine and sitting postures, the effect was greater while supine. Fluctuation in shear pattern seen during both positions may account for positive clinical effects observed following intermittent negative pressure treatment. These findings are framed against previous work investigating clinical populations. Future work should investigate any differences in lower limb haemodynamics and markers of endothelial function among patients with vascular disease.
Objective: We investigated the effects of lower extremity intermittent negative pressure (INP) treatment for 1 hour two times daily for 12 weeks on the walking distance of patients with intermittent claudication (IC). Methods: Patients with IC were randomized to treatment with -40 mm Hg INP (treatment group) or -10 mm Hg INP (sham control group). Pain-free walking distance (PWD) and maximal walking distance (MWD) on a treadmill, resting and postexercise ankle-brachial index, resting and postischemic blood flow (plethysmography), and quality of life (EQ-5D-5L and Vascuqol-6) were measured at baseline and after 12 weeks of treatment. Results: A total of 72 patients were randomized, and 63 had data available for the intention-to-treat analyses. The between-group comparisons showed a significant change in the PWD, favoring the treatment group over the sham control group (estimated treatment effect, 50 m; 95% confidence interval [CI], 11-89; P = .014). The PWD had increased by 68 m (P < .001) in the treatment group and 18 m (P = .064) in the sham control group. No significant difference was found in the change in the MWD between the two groups (estimated treatment effect, 42 m; 95% CI, -14 to 97; P = .139). The MWD had increased by 62 m (P = .006) in the treatment group and 20 m (P = .265) in the sham control group. For patients with a baseline PWD of <200 m (n = 56), significant changes had occurred in both PWD and MWD between the two groups, favoring the treatment group (estimated treatment effect, 42 m; 95% CI, 2-83; P = .042; and estimated treatment effect, 62 m; 95% CI, 5-118; P = .032; respectively). Both overall and for the group of patients with a PWD <200 m, no significant differences were found in the changes in the resting and postexercise ankle-brachial index, resting and postischemic blood flow, or quality of life parameters between the two groups. Conclusions: Treatment with -40 mm Hg INP increased the PWD compared with sham treatment in patients with IC. For the patients with a baseline PWD of <200 m, an increase was found in both PWD and MWD compared with sham treatment.
The aim of this study was to investigate the effects of lower extremity intermittent negative pressure (INP) treatment for 1 hour twice daily for 12 weeks, on circulating vascular biomarkers in patients with intermittent claudication. Patients were randomized to treatment with –40 mmHg INP (treatment group), or –10 mmHg INP (sham control group). Venous blood samples were collected at baseline and after 12 weeks, and concentrations of vascular adhesion molecule-1 (VCAM-1), intracellular adhesion molecule-1 (ICAM-1), E-selectin, P-selectin, von Willebrand factor (vWF), l-arginine, asymmetric dimethylarginine (ADMA), and symmetric dimethylarginine (SDMA) were analyzed. A larger proportion of the patients in the treatment group (25/31) had a reduction in vWF levels after 12 weeks, compared to the sham control group (17/30) ( p = 0.043). Within the treatment group there was a significant mean (SEM) reduction in the concentration of vWF of –11% (4) ( p = 0.019), whereas there was no significant change in the levels of vWF in the sham control group (1% (6); p = 0.85). There were no significant differences in the change of any of the biomarker levels between the groups after 12 weeks of treatment. In conclusion, there were no differences in the change of the circulating levels of the measured biomarkers between the treatment group and the sham control group after 12 weeks of INP treatment. However, the observed changes in vWF might indicate a beneficial effect of INP treatment on endothelial activation and endothelial injury. Clinicaltrials.gov Identifier: NCT03640676
Background: Treatment with lower extremity intermittent negative pressure (INP) of-40 mm Hg for one hour twice daily for 12 weeks, increases walking capacity in patients with intermittent claudication (IC). However, the effects of INP treatment beyond 12 weeks have not been elucidated. The aim of the present study was to investigate the clinical effects of INP treatment after 24 weeks in patients with IC. Methods: This was a follow-up study after a randomized sham-controlled trial, where patients randomized to the active treatment group were offered to continue treatment for 12 additional weeks (24 weeks in total). Treatment with-40 mm Hg INP was applied in a pressure chamber sealed around the lower leg, and the patients were instructed to treat themselves at home one hour in the morning and one hour in the evening. Pain free walking distance (PWD), maximal walking distance (MWD), resting ankle-brachial index (ABI) and post exercise ABI were measured at baseline, after 12 and 24 weeks. Results: Ten out of 32 patients (31%) from the active treatment group in the initial trial were included in this follow-up study. At baseline, PWD was (mean +/- SD) 151 +/- 91 m and MWD was 362 +/- 159 m. There was a significant increase in both PWD and MWD after 24 weeks of treatment, compared to baseline (ANOVA; P = 0.006 and P = 0.012, respectively). Post hoc tests revealed that PWD increased significantly from baseline to 12 weeks (mean 81 m; 95% CI [6, 156]; P = 0.032), and that MWD increased significantly from 12 to 24 weeks (mean 145 m; 95% CI [22, 268]; P = 0.018). There were no significant changes in resting ABI or post exercise ABI during the 24-week treatment period (ANOVA; P = 0.157 and P = 0.450, respectively). Conclusion: Both PWD and MWD improved after treatment with - 40 mm Hg INP for one hour twice daily for 24 weeks, compared to baseline. The main improvement in PWD occurred during the first 12 weeks of treatment, whereas the main improvement in MWD occurred between 12 and 24 weeks of treatment.
Study design Randomized, assessor-blinded crossover pilot study. Objectives To explore the use of an intermittent negative pressure (INP) device for home use in addition to standard wound care (SWC) for patients with spinal cord injury (SCI) and chronic leg and foot ulcers before conducting a superiority trial. Setting Patient homes and outpatient clinic. Methods A 16-week crossover trial on 9 SCI patients (median age: 57 years, interquartile range [IQR] 52–66), with leg ulcers for 52 of weeks (IQR: 12–82) duration. At baseline, patients were allocated to treatment with INP + SWC or SWC alone. After 8 weeks, the ulcers were evaluated. To assess protocol adherence, the patients were then crossed over to the other group and were evaluated again after another 8 weeks. Lower limb INP treatment consisted of an airtight pressure chamber connected to an INP generator (alternating 10 s −40mmHg/7 s atmospheric pressure) used 2 h/day at home. Ulcer healing was assessed using a photographic wound assessment tool (PWAT) and by measuring changes in wound surface area (WSA). Results Seven of nine recruited patients adhered to a median of 90% (IQR: 80–96) of the prescribed 8-week INP-protocol, and completed the study without side effects. PWAT improvement was observed in 4/4 patients for INP + SWC vs. 2/5 patients for SWC alone ( P = 0.13). WSA improved in 3/4 patients allocated to INP + SWC vs. 3/5 patients in SWC alone ( P = 0.72). Conclusions INP can be used as a home-based treatment for patients with SCI, and its efficacy should be tested in an adequately sized, preferably multicenter randomized trial.
Study Design Experimental prestudy and poststudy. Objectives Examine the acute effects of intermittent negative pressure (INP) applied to the lower limb on foot circulation in people with spinal cord injuries (SCIs). Setting Vascular laboratory, Oslo University Hospital. Methods Twenty-four people with SCI (median age 59 years, range 29–74) were exposed to lower leg INP (−40 mm Hg) using an air-tight pressure chamber connected to an INP generator. The contralateral leg was placed outside the pressure chamber. We continuously measured arterial blood flow velocity (ultrasound Doppler), skin blood flow (laser Doppler), skin temperature of the dorsum of the foot, heart rate (ECG) and systemic blood pressure (Finometer) during 5-min baseline (atmospheric pressure), followed by 10-min INP (alternating 10 s −40 mm Hg and 7 s atmospheric pressure), and 5-min post-INP (atmospheric pressure). Skin blood flow was measured on the foot placed outside the pressure chamber. A mixed effects regression model was applied to estimate the effect of INP on blood flow. To quantify flow fluctuations, we calculated cumulative up-and-down changes in arterial blood flow velocity per minute. Results Flow fluctuations increased during INP compared to baseline [32.3 cm/s/min (95% CI 26.9 to 37.7) vs. 15.2 cm/s/min (95% CI 9.8 to 20.6), P < 0.001]. Peak blood flow velocity and skin blood flow was reached 2–3 s after the onset of negative pressure and increased 33% (95% CI 16 to 46, P < 0.001) and 11% (95% CI −4.1 to 60, P = 0.14) above baseline, respectively. Conclusions INP induced increased foot arterial blood flow fluctuations compared to baseline. Sponsorships The Norwegian Research Council provided funding to Otivio (grant: 241589).
Clearance of infections caused by the hepatitis C virus (HCV) correlates with HCV-specific T cell function. We therefore evaluated therapeutic vaccination in 12 patients with chronic HCV infection. Eight patients also underwent a subsequent standard-of-care (SOC) therapy with pegylated interferon (IFN) and ribavirin. The phase I/IIa clinical trial was performed in treatment naive HCV genotype 1 patients, receiving four monthly vaccinations in the deltoid muscles with 167, 500, or 1,500 μg codon-optimized HCV nonstructural (NS) 3/4A-expressing DNA vaccine delivered by in vivo electroporation (EP). Enrollment was done with 2 weeks interval between patients for safety reasons. Treatment was safe and well tolerated. The vaccinations significantly improved IFN-γ-producing responses to HCV NS3 during the first 6 weeks of therapy. Five patients experienced 2-10 weeks 0.6-2.4 log10 reduction in serum HCV RNA. Six out of eight patients starting SOC therapy within 1-30 months after the last vaccine dose were cured. This first-in-man therapeutic HCV DNA vaccine study with the vaccine delivered by in vivo EP shows transient effects in patients with chronic HCV genotype 1 infection. The interesting result noted after SOC therapy suggests that therapeutic vaccination can be explored in a combination with SOC treatment.
We report on the immunogenicity and clinical effects in a phase I/II dose escalation trial of a DNA fusion vaccine in patients with prostate cancer. The vaccine encodes a domain (DOM) from fragment C of tetanus toxin linked to an HLA-A2-binding epitope from prostate-specific membrane antigen (PSMA), PSMA(27-35). We evaluated the effect of intramuscular vaccination without or with electroporation (EP) on vaccine potency. Thirty-two HLA-A2(+) patients were vaccinated and monitored for immune and clinical responses for a follow-up period of 72 weeks. At week 24, cross-over to the immunologically more effective delivery modality was permitted; this was shown to be with EP based on early antibody data, and subsequently, 13/15 patients crossed to the +EP arm. Thirty-two HLA-A2(-) control patients were assessed for time to next treatment and overall survival. Vaccination was safe and well tolerated. The vaccine induced DOM-specific CD4(+) and PSMA(27)-specific CD8(+) T cells, which were detectable at significant levels above baseline at the end of the study (p = 0.0223 and p = 0.00248, respectively). Of 30 patients, 29 had a measurable CD4(+) T-cell response and PSMA(27)-specific CD8(+) T cells were detected in 16/30 patients, with or without EP. At week 24, before cross-over, both delivery methods led to increased CD4(+) and CD8(+) vaccine-specific T cells with a trend to a greater effect with EP. PSA doubling time increased significantly from 11.97 months pre-treatment to 16.82 months over the 72-week follow-up (p = 0.0417), with no clear differential effect of EP. The high frequency of immunological responses to DOM-PSMA(27) vaccination and the clinical effects are sufficiently promising to warrant further, randomized testing.
Background and Aims: FHF has high mortality without liver transplantation.Many prognostic models are available to predict the clinical outcome in patients of FHF.Our objective was to assess the usefulness of serum levels and gene expression of HGF in determining the prognosis in patients of FHF.Methods: A total of 108 subjects were enrolled, out of these 25 patients were of FHF, 33 had acute hepatitis and 50 were healthy controls.Serum levels were studied in each group at admission and at end point.Semi-quantitative analysis of gene expression of HGF was done from blood in each group and also from hepatic tissue of FHF patients who expired.These results were then analyzed for any statistical significance as prognostic markers.Results: There was significant difference (p = 0.038) between mean HGF concentration of FHF patients who expired (FHE) 12.268±2.622and FHF patients who survived (FHS) 3.6±0.8271when admission levels were compared.HGF levels were significantly higher at expiry (17.868±4.19)than at admission (12.268±2.622) in FHE subgroup (p = 0.04) whereas in FHS subgroup recovery levels (0.908±0.244) were significantly (p = 0.005) lower than the admission levels(3.6±0.82).FHE subgroup 13/16 (81.25%) had comparatively higher expression of HGF (in blood) at expiry then at the time of admission.In FHS subgroup 7/9 (77.78%) patients who recovered the expression of HGF was higher at admission then at recovery.Out of the 9 postmortem biopsies and 10 control biopsies (autopsy cases) no difference in expression was found in both the groups. Conclusion:The admission serum levels of HGF may be used as a prognostic marker in patients of FHF.An increase in serum levels after admission may signify grave prognosis whereas a decrease in levels can be seen as a sign of recovery.There is upregulation of HGF gene expression in blood in FHF with a positive correlation with disease severity.The gene expression of HGF in hepatic tissue in FHF is no different from the expression in normal healthy controls, so liver is unlikely to be the source of the raised HGF serum levels.
We are evaluating the use of electroporation (EP) to deliver a novel DNA vaccine, p.DOM-PSMA27. This vaccine encodes a domain (DOM) of fragment C of tetanus toxin to induce CD4+ T cell help, fused to a tumor-derived epitope from prostate-specific membrane antigen (PSMA) for use in HLA-A2+ patients with recurrent prostate cancer. We report on safety and tolerability and on antibody response to DOM as a first indication of the effect of EP in patients. In this open label phase I/II, two-arm, dose escalation trial DNA was delivered either by intramuscular injection or by intramuscular injection followed by EP (DNA+EP), with five patients per dose level. Three vaccinations were given at 0, 4, and 8 weeks,with booster doses at 24 and 48 weeks; here we allowed crossover between study arms if supported by the safety and immunological data. In the 20 patients in the first two dose cohorts we observed that beyond brief and acceptable pain at the injection site, EP did not appear to add toxicity to the vaccination. We evaluated humoral responses to DOM. Low anti-DOM IgG antibody responses were observed after intramuscular injection of DNA without EP (at week 12: mean 1.7- vs. 24.5-fold increase over baseline with DNA+EP). These could be boosted by delivery of DNA+EP at later time points. Delivery of DNA+EP at all five vaccinations yielded the highest levels of anti-DOM antibody. Responses persisted to 18 months of follow-up. These data establish EP as a potent method for stimulating humoral responses induced by DNA vaccination in humans.