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1.
Preprint in English | medRxiv | ID: ppmedrxiv-22276509

ABSTRACT

BackgroundOmicron variant questioned the efficacy of the approved therapies for the early COVID-19. I In vitro data show retained neutralizing activity against BA.1 and BA.2 for remdesivir (RDV), molnupiravir (MLN), and nirmatrelvir/ritonavir (NRM/r), while poor efficacy for Sotrovimab (STR) against BA.2. No data about the risk of clinical failure and in vivo antiviral activity are available. Material and methodsSingle-center observational comparison study enrolling all consecutive patients with a confirmed SARS-CoV-2 Omicron (BA.1 or BA.2) diagnosis and who met eligibility criteria for treatment with RDV, MLN, NRM/r, or STR. Treatment allocation was subject to drug availability, time from symptoms onset, and comorbidities. Patients were followed through day 30. Nasopharyngeal swab (NPS) VL was measured on day 1 (D1) and D7 and was expressed by log2 cycle threshold (CT) scale. Comparisons between groups were made by Chi-square and Wilcoxon paired-test. Primary endpoint was D1-D7 VL variation. Potential decrease in VL and average treatment effect (ATE) were calculated from fitting marginal linear regression models weighted for calendar month of infusion, duration of symptoms, and immunodeficiency. Secondary endpoints were the proportion of D7 undetectable VL in NPS and clinical outcomes compared by treatment groups using a Chi-square test. ResultsA total of 521 pts received treatments (STR 202, MLN 117, NRM/r 84, and RDV 118): female 250 (48%), median age 66 yrs (IQR 55-76), 90% vaccinated; 15% with negative baseline serology. At D1, median time from symptoms onset was 3 days (2,4). 378 (73%) pts were infected with BA.1 and 143 (27%) with BA.2. D1 mean viral load was 4.12 log2 (4.16 for BA.1 and 4.01 for BA.2). The adjusted analysis showed that NRM/r significantly reduced VL compared to all the other drugs in pts infected with BA.1 while no evidence for a difference vs. MLP was seen in those infected with BA.2. MLN had comparable activity to STR against BA.1 and to NRM/r against BA.2. There was no significant difference between STR and RDV for BA.2. At D7, 35/521 (6.7%) pts had undetectable VL. Of these, 31 were infected with BA.1 [9 (9%) MLN, 7 (14%) NRM/r, 7 (8%) RDV, and 8 (5%) STR)], and only 4 with BA.2, all treated with NRM/r. After 30 days of follow-up, 9/568 pts experienced COVID-19-related clinical failure [7/226 STR (5 BA.1) and 2/87 NRM /r (2 BA.1)]. ConclusionsIn this analysis of in vivo early VL reductions, NRM/r appears to be the drug showing the greatest antiviral activity regardless of the VoC, together with MLN, although the latter limited to people with BA.2. In the Omicron era, due to the high prevalence of vaccinated people and the lower probability of hospital admission, VL decrease can be a valuable surrogate of drug activity.

2.
Preprint in English | medRxiv | ID: ppmedrxiv-22270143

ABSTRACT

ObjectivesComparative analysis between different monoclonal antibodies (mAbs) against SARS-CoV-2 are lacking. We present an emulation trial from observational data to compare effectiveness of Bamlanivimab/Etesevimab (BAM/ETE) and Casirivimab/Imdevimab (CAS/IMD) in outpatients with early mild-to-moderate COVID-19 in a real-world scenario of variants of concern (VoCs) from Alpha to Delta. MethodsAllocation to treatment was subject to mAbs availability, and the measured factors were not used to determine which combination to use. Patients were followed through day 30. Viral load was measured by cycle threshold (CT) on D1 (baseline) and D7. Primary outcome was time to COVID-19-related hospitalization or death from any cause over days 0-30. Weighted pooled logistic regression and marginal structural Cox model by inverse probability weights were used to compare BAM/ETE vs. CAS/IMD. ANCOVA was used to compare mean D7 CT values by intervention. Models were adjusted for calendar month, MASS score and VoCs. We evaluated effect measure modification by VoCs, vaccination, D1 CT levels and enrolment period. ResultsCOVID19-related hospitalization or death from any cause occurred in 15 of 237 patients in the BAM/ETE group (6.3%) and in 4 of 196 patients in the CAS/IMD group (2.0%) (relative risk reduction [1 minus the relative risk] 72%; p=0.024). Subset analysis carried no evidence that the effect of the intervention was different across stratification factors. There was no evidence in viral load reduction from baseline through day 7 across the two groups (+0.17, 95% -1.41;+1.74, p=0.83). Among patients who experienced primary outcome, none showed a negative RT-PCR test in nasopharingeal swab (p=0.009) and 82.4% showed still high viral load (p<0.001) on D7. ConclusionsIn a pre-Omicron epidemiologic scenario, CAS/IMD reduced risk of clinical progression of COVID-19 compared to BAM/ETE. This effect was not associated with a concomitant difference in virological response.

3.
Preprint in English | medRxiv | ID: ppmedrxiv-22269335

ABSTRACT

The new variant Omicron (B.1.1.529) of SARS-CoV-2, first identified in November 2021, is rapidly spreading all around the world. The Omicron becomes the dominant variant of SARS-CoV-2. There are many ongoing studies evaluating the effectiveness of existing vaccines. Studies on neutralizing activity of vaccinated sera against Omicron variant are currently being carried out in many laboratories. In this study, we have shown the neutralizing activity of sera against SARS-CoV-2 Omicron (B.1.1.529) variant compared to the reference Wuhan D614G (B.1) variant in individuals vaccinated with 2 doses of Sputnik V or BNT162b2 in different time points up to 6 months after vaccination. We performed analysis on sample pools with comparable NtAb to Wuhan D614G variant. The decrease in neutralizing antibody (NtAb) to the Omicron variant was 8.1 folds for group of Sputnik V-vaccinated and 21.4 folds for group of BNT162b2-vaccinated. Analysis showed that 74.2% of Sputnik V- and 56.9% of BNT162b2-vaccinated sera had detectable NtAb to SARS-CoV-2 Omicron variant. The decrease in NtAb to SARS-CoV-2 Omicron variant compared to Wuhan variant has been shown for many COVID-19 vaccines in use, with some showing no neutralization at all. Today the necessity of third booster vaccination is obvious. And the most effective approach, already shown in several studies, is the use of heterologous booster vaccination pioneered in COVID-19 vaccines by Sputnik V.

4.
Preprint in English | medRxiv | ID: ppmedrxiv-21261441

ABSTRACT

BackgroundThe emerging threat represented by SARS-CoV-2 variants, demands the development of therapies for better clinical management of COVID-19. MAD0004J08 is an extremely potent Fc-engineered monoclonal antibody (mAb) able to neutralise in vitro all current SARS-CoV-2 variants of concern (VoCs). This ongoing study, evaluates safety, pharmacokinetics and SARS-CoV-2 sera neutralization effect of MAD0004J08 when administered as single dose intramuscularly in healthy adults. MethodWe conducted a dose escalation study with sequential enrolment of three cohorts, each with an increasing dose level of MAD0004J08 (48mg, 100mg and 400mg). Within each cohort, 10 young healthy adults were randomized with 4:1 ratio to a single intramuscular (i.m.) injection of MAD0004J08 or placebo. The primary endpoint is the proportion of subjects with severe and/or serious treatment emergent adverse events (TEAEs) within 7 days post-treatment. Secondary endpoints reported in this paper are the proportion of subjects with solicited TEAEs up 7 days post dosing, MAD0004J08 serum concentrations and neutralising activity versus the original SARS-COV-2 Wuhan virus at different timepoints post-dosing. As post-hoc analyses, we compared the sera neutralising titres of subjects who received MAD0004J08 with those of people that had received the COVID-19 BNT162b2 mRNA vaccine in the previous sixty days (n=10) and COVID-19 convalescent patients (n=20), and assessed serum neutralisation activity against the B.1.1.7 (alpha), B.1.351 (beta) and B.1.1.248 (gamma) SARS-CoV-2 variants of concern. FindingsA total of 30 subjects, 10 per cohort, were enrolled and randomized. Data up to 30 days were available and analysed in this report. No severe TEAEs were reported in any of the cohorts in the 7 days post-treatment. MAD0004J08 was detected in the sera of treated subjects within few hours post-administration and reached almost maximal levels on day 8. The geometric mean neutralising titres (GMT) assessed against the original Wuhan virus peaked on day 8 and ranged 226 - 905, 905 - 2,560, and 1,280 - 5,120 for cohort 1, 2 and 3 respectively. The sera neutralising GMT in MAD0004J08 treated subjects in all the three cohorts were found to be 1{middle dot}5-54{middle dot}5-fold higher compared to sera from convalescent patients and 1{middle dot}83- 76{middle dot}4-fold higher compared to sera from COVID-19 vaccinees. Finally, GMT in MAD0004J08 treated subjects showed high neutralising titres versus the B.1.1.7 (alpha), B.1.351 (beta) and B.1.1.248 (gamma) SARS-CoV-2 VoCs. InterpretationA single dose administration of MAD0004J08 via i.m. route is safe and well tolerated and results in a rapid systemic distribution of the MAD0004J08 and sera neutralising titres higher than COVID-19 convalescent and vaccinated subjects. A single dose administration of MAD0004J08 is also sufficient to effectively neutralise major SARS-CoV-2 variants of concern. Based on these results, a Phase 2-3 trial is ongoing to further assess the safety, dosage, and efficacy of MAD0004J08 in asymptomatic or mild-moderate symptomatic COVID-19 patients. FundingEU Malaria Fund, Ministero dello Sviluppo Economico, Ministero della Salute, Regione Toscana, Toscana Life Sciences Sviluppo and European Research Council. Research in contextO_ST_ABSEvidence before this studyC_ST_ABSWe searched PUBMED, MEDLINE and MedRxiv for clinical trials, meta-analyses and randomized controlled trials evaluating the antibody neutralization titres vs. different SARS-CoV-2 variants of concern obtained from subjects who received monoclonal antibodies for the treatment of COVID-19 using the following search terms: ("COVID-19" OR "SARS-CoV-2") AND ("monoclonal antibody" OR "neutralising antibody") AND ("variants" OR "variants of concern"). No relevant studies were identified. Added value of this studyThis is the first human study assessing safety, PK and neutralising potential of MAD0004J08, a monoclonal antibody against SARS-CoV-2 wild type Wuhan virus and variants of concern, administered intramuscularly at low dosages (48, 100 and 400 mg). MAD0004J08 showed to be safe and well tolerated in the tested dose range. Anti-spike antibodies were detected in the sera of tested SARS-CoV-2 negative healthy adults few hours post-injection. In addition, the sera obtained from MAD0004J08treated subjects, showed to have high neutralisation titres against the Wuhan virus, the B.1.1.7 (alpha), B.1.351 (beta) and B.1.1.248 (gamma) variants of concern. Implications of all the available evidenceA potent monoclonal antibody such as MAD0004J08, capable of neutralising multiple variants of concern of SARS-CoV-2 rapidly and long lastingly when given as a single intramuscular injection. The antibody, presently tested in a phase 2-3 efficacy trial, can be a major advancement in the prophylaxis and clinical management of COVID-19, because of its broad spectrum, ease of use in non-hospital settings and economic sustainability.

5.
Preprint in English | medRxiv | ID: ppmedrxiv-21255202

ABSTRACT

Safe and effective vaccines against coronavirus disease 2019 (COVID-19) are urgently needed to control the ongoing pandemic. Although impressive progress has been made with several COVID-19 vaccines already approved, it is clear that those developed so far cannot meet the global vaccine demand. We have developed a COVID-19 vaccine based on a replication-defective gorilla adenovirus expressing the stabilized pre-fusion SARS-CoV-2 Spike protein, named GRAd-COV2. We aimed to assess the safety and immunogenicity of a single-dose regimen of this vaccine in healthy younger and older adults to select the appropriate dose for each age group. To this purpose, a phase 1, dose-escalation, open-label trial was conducted including 90 healthy subjects, (45 aged 18-55 years and 45 aged 65-85 years), who received a single intramuscular administration of GRAd-CoV2 at three escalating doses. Local and systemic adverse reactions were mostly mild or moderate and of short duration, and no serious AE was reported. Four weeks after vaccination, seroconversion to Spike/RBD was achieved in 43/44 young volunteers and in 45/45 older subjects. Consistently, neutralizing antibodies were detected in 42/44 younger age and 45/45 older age volunteers. In addition, GRAd-COV2 induced a robust and Th1-skewed T cell response against the S antigen in 89/90 subjects from both age groups. Overall, the safety and immunogenicity data from the phase 1 trial support further development of this vaccine. One Sentence SummaryGRAd-COV2, a candidate vaccine for COVID-19 based on a novel gorilla adenovirus, is safe and immunogenic in younger and older adults

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