First pilot case-control interventional study using autologous extracellular vesicles to treat chronic venous ulcers unresponsive to conventional treatments

Current therapeutic approaches for chronic venous ulcers (CVUs) still require evidence of effectiveness. Diverse sources of extracellular vesicles (EVs) have been proposed for tissue regeneration, however the lack of potency tests, to predict in-vivo effectiveness, and a reliable scalability have delayed their clinical application. This study aimed to investigate whether autologous serum-derived EVs (s-EVs), recovered from patients with CVUs, may be a proper therapeutic approach to improve the healing process. A pilot case-control interventional study (CS2/1095/0090491) has been designed and s-EVs recovered from patients. Patient eligibility included two or more distinct chronic lesions in the same limb with 11 months as median persistence of active ulcer before enrollment. Patients were treated three times a week, for 2 weeks. Qualitative CVU analysis demonstrated that s-EVs-treated lesions displayed a higher percentage of granulation tissue compared to the control group (Sham) (s-EVs 3 out of 5: 75–100 % vs Sham: none), further confirmed at day 30. s-EVs-treated lesions also displayed higher sloughy tissue reduction at the end of treatment even increased at day 30. Additionally, s-EV treatment led to a median surface reduction of 151 mm2 compared to 84 mm2 in the Sham group, difference even more evident at day 30 (s-EVs 385 mm2 vs Sham 106 mm2 p = 0.004). Consistent with the enrichment of transforming growth factor-β1 in s-EVs, histological analyses showed a regenerative tissue with an increase in microvascular proliferation areas. This study first demonstrates the clinical effectiveness of autologous s-EVs in promoting the healing process of CVUs unresponsive to conventional treatments

Timing of blood sampling and HCV-RNA results on PBMCs during follow-up of OCI subjects.

<p>NOTE: Normal characters indicate baseline samples. Italics indicates follow-up samples.</p><p>Abbreviations: N, negative result.</p

Serological and virological characteristics of subjects with occult hepatitis C virus (HCV) infection.

*<p>AST and ALT values at recruitment; −/−: normal values of AST: below 40 IU/L and 32 IU/L for men and women respectively, and ALT: below 50 IU/L and 35 IU/L for men and women respectively. +/+ altered levels of AST and ALT.</p>**<p>GGT and ALP values; −/−: normal values of GTT: below 50 IU/L and 35 IU/L for men and women respectively, and ALP: below 128 IU/L and 141 IU/L for men and women respectively.</p>***<p>Liver functional tests: total plasma protein, albumin, cholesterol, total and fractionated bilirubin, prothrombin time, partial thromboplastin time, and international normalised ratio.</p>§<p>PBMCs viral load on baseline sample.</p><p>Abbreviations: SE, secondary erythrocytosis; PV, polycythemia vera; HBV, hepatitis B virus; AST, aspartate aminotransferase; ALT, alanine aminotransferase; GGT, gamma glutamyl transpeptidase; ALP, alkaline phosphatase, n.d., not determined because the amplification resulted in a very weak fragment and sequence analysis did not succeed; PBMCs, peripheral blood mononuclear cells.</p

Flow chart of distribution of subjects enrolled in the study based on presence of serological markers of human immunodeficiency virus (HIV), hepatitis C virus (HCV) and hepatitis B virus (HBV).

<p>Subjects positive for HBsAg and/or HBV-DNA were considered carriers of HBV. Subjects positive for anti-HCV and HCV-RNA or anti-HCV positive confirmed by the RIBA assay even though negative for HCV-RNA were considered HCV infection. Subjects HBsAg negative, anti-HBc positive with or without anti-HBs and HBV-DNA negative with normal alanine aminotransferase levels were considered previously HBV infected and naturally immunized. Abbreviations: anti-HIV, HIV antibodies; anti-HCV, antibodies against HCV; HBsAg, hepatitis B surface antigen; anti-HBc, hepatitis B core antibodies; pos, positive; neg, negative.</p

HCV-RNA detection in plasma and PBMCs.

<p>Abbreviations: HCV, hepatitis C virus; PBMC, peripheral blood mononuclear cells; HBV, hepatitis B virus.</p

Association between convalescent plasma treatment and mortality in COVID-19: a collaborative systematic review and meta-analysis of randomized clinical trials

Abstract Background Convalescent plasma has been widely used to treat COVID-19 and is under investigation in numerous randomized clinical trials, but results are publicly available only for a small number of trials. The objective of this study was to assess the benefits of convalescent plasma treatment compared to placebo or no treatment and all-cause mortality in patients with COVID-19, using data from all available randomized clinical trials, including unpublished and ongoing trials (Open Science Framework, https://doi.org/10.17605/OSF.IO/GEHFX ). Methods In this collaborative systematic review and meta-analysis, clinical trial registries (ClinicalTrials.gov, WHO International Clinical Trials Registry Platform), the Cochrane COVID-19 register, the LOVE database, and PubMed were searched until April 8, 2021. Investigators of trials registered by March 1, 2021, without published results were contacted via email. Eligible were ongoing, discontinued and completed randomized clinical trials that compared convalescent plasma with placebo or no treatment in COVID-19 patients, regardless of setting or treatment schedule. Aggregated mortality data were extracted from publications or provided by investigators of unpublished trials and combined using the Hartung–Knapp–Sidik–Jonkman random effects model. We investigated the contribution of unpublished trials to the overall evidence. Results A total of 16,477 patients were included in 33 trials (20 unpublished with 3190 patients, 13 published with 13,287 patients). 32 trials enrolled only hospitalized patients (including 3 with only intensive care unit patients). Risk of bias was low for 29/33 trials. Of 8495 patients who received convalescent plasma, 1997 died (23%), and of 7982 control patients, 1952 died (24%). The combined risk ratio for all-cause mortality was 0.97 (95% confidence interval: 0.92; 1.02) with between-study heterogeneity not beyond chance (I2 = 0%). The RECOVERY trial had 69.8% and the unpublished evidence 25.3% of the weight in the meta-analysis. Conclusions Convalescent plasma treatment of patients with COVID-19 did not reduce all-cause mortality. These results provide strong evidence that convalescent plasma treatment for patients with COVID-19 should not be used outside of randomized trials. Evidence synthesis from collaborations among trial investigators can inform both evidence generation and evidence application in patient care

Association between convalescent plasma treatment and mortality in COVID-19: a collaborative systematic review and meta-analysis of randomized clinical trials

Abstract Background Convalescent plasma has been widely used to treat COVID-19 and is under investigation in numerous randomized clinical trials, but results are publicly available only for a small number of trials. The objective of this study was to assess the benefits of convalescent plasma treatment compared to placebo or no treatment and all-cause mortality in patients with COVID-19, using data from all available randomized clinical trials, including unpublished and ongoing trials (Open Science Framework, https://doi.org/10.17605/OSF.IO/GEHFX ). Methods In this collaborative systematic review and meta-analysis, clinical trial registries (ClinicalTrials.gov, WHO International Clinical Trials Registry Platform), the Cochrane COVID-19 register, the LOVE database, and PubMed were searched until April 8, 2021. Investigators of trials registered by March 1, 2021, without published results were contacted via email. Eligible were ongoing, discontinued and completed randomized clinical trials that compared convalescent plasma with placebo or no treatment in COVID-19 patients, regardless of setting or treatment schedule. Aggregated mortality data were extracted from publications or provided by investigators of unpublished trials and combined using the Hartung–Knapp–Sidik–Jonkman random effects model. We investigated the contribution of unpublished trials to the overall evidence. Results A total of 16,477 patients were included in 33 trials (20 unpublished with 3190 patients, 13 published with 13,287 patients). 32 trials enrolled only hospitalized patients (including 3 with only intensive care unit patients). Risk of bias was low for 29/33 trials. Of 8495 patients who received convalescent plasma, 1997 died (23%), and of 7982 control patients, 1952 died (24%). The combined risk ratio for all-cause mortality was 0.97 (95% confidence interval: 0.92; 1.02) with between-study heterogeneity not beyond chance (I2 = 0%). The RECOVERY trial had 69.8% and the unpublished evidence 25.3% of the weight in the meta-analysis. Conclusions Convalescent plasma treatment of patients with COVID-19 did not reduce all-cause mortality. These results provide strong evidence that convalescent plasma treatment for patients with COVID-19 should not be used outside of randomized trials. Evidence synthesis from collaborations among trial investigators can inform both evidence generation and evidence application in patient care