XAV-19 for COVID-19

Background: XAV-19 is a glyco-humanized swine polyclonal antibody targeting SARS-CoV-2. The safety and clinical efficacy of XAV-19 was investigated in patients with a WHO score of 2 to 4 in the WHO 7-point ordinal scale. The activity of XAV-19 against Omicron and its subvariants was assessed in vitro. Methods: A phase II/III, multicentric randomized double-blind placebo-controlled, clinical trial was conducted to evaluate the safety and clinical efficacy of XAV-19 in inpatients with COVID-19 requiring or not oxygen therapy and outpatients not requiring oxygen (EUROXAV trial,NCT04928430). Most patients were not vaccinated. The primary endpoint was the proportion of patients with an aggravation of COVID-19 within 8 days after treatment. Binding and neutralization of Omicron or its subvariants by XAV-19 was investigated by ELISA or with a whole virus neutralization assay. Results: Patients received either 150mg of XAV-19 (N=139) or placebo (N=140). Low enrolment forced the premature trial termination. XAV-19 was well tolerated. No difference in the primary endpoint, nor in the proportion with an improvement at day 8 (secondary endpoint) was observed between the 2 groups. For patients not requiring oxygen therapy, XAV-19 reduced the time to improvement significantly (7 days vs 14 days p=0.0159). Neutralizing activity against Omicron and BA.2, BA2.12.1, BA.4/5 and BQ1.1 subvariants was shown in vitro. Conclusions: XAV-19 did not reduce the aggravation in COVID-19 patients. While it did not bring any benefit to patients requiring oxygen, it reduced the time to improvement for patients not requiring oxygen (WHO score 2 or 3). These preliminary clinical data might indicate a therapeutic potential for patients with mild to moderate COVID-19 requiring supplementation with anti-SARS-CoV-2 neutralizing antibodies.

Abstract Background We evaluated the safety and efficacy of XAV-19, an antispike glyco-humanized swine polyclonal neutralizing antibody in patients hospitalized with severe coronavirus disease 2019 (COVID-19). Methods This phase 2b clinical trial enrolled adult patients from 34 hospitals in France. Eligible patients had a confirmed diagnosis of severe acute respiratory syndrome coronavirus 2 within 14 days of onset of symptoms that required hospitalization for low-flow oxygen therapy (<6 L/min of oxygen). Patients were randomly assigned to receive a single intravenous infusion of 2 mg/kg of XAV-19 or placebo. The primary end point was the occurrence of death or severe respiratory failure between baseline and day 15. Results Between January 12, 2021, and April 16, 2021, 398 patients were enrolled in the study and randomly assigned to XAV-19 or placebo. The modified intention-to-treat population comprised 388 participants who received full perfusion of XAV-19 (199 patients) or placebo (189 patients). The mean (SD) age was 59.8 (12.4) years, 249 (64.2%) individuals were men, and the median time (interquartile range) from symptom onset to enrollment was 9 (7–10) days. There was no statistically significant decrease in the cumulative incidence of death or severe respiratory failure through day 15 in the XAV-19 group vs the placebo group (53/199 [26.6%] vs 48/189 [25.4%]; adjusted risk difference, 0.6%; 95% CI, −6% to 7%; hazard ratio, 1.03; 95% CI, 0.64–1.66; P = .90). In the safety population, adverse events were reported in 75.4% of 199 patients in the XAV-19 group and in 76.3% of 190 patients in the placebo group through D29. Conclusions Among patients hospitalized with COVID-19 requiring low-flow oxygen therapy, treatment with a single intravenous dose of XAV-19, compared with placebo, did not show a significant difference in terms of disease progression at day 15.

By January of 2023, the COVID-19 pandemic had led to a reported total of 6,700,883 deaths and 662,631,114 cases worldwide. To date, there have been no effective therapies or standardized treatment schemes for this disease; therefore, the search for effective prophylactic and therapeutic strategies is a primary goal that must be addressed. This review aims to provide an analysis of the most efficient and promising therapies and drugs for the prevention and treatment of severe COVID-19, comparing their degree of success, scope, and limitations, with the aim of providing support to health professionals in choosing the best pharmacological approach. An investigation of the most promising and effective treatments against COVID-19 that are currently available was carried out by employing search terms including “Convalescent plasma therapy in COVID-19” or “Viral polymerase inhibitors” and “COVID-19” in the Clinicaltrials.gov and PubMed databases. From the current perspective and with the information available from the various clinical trials assessing the efficacy of different therapeutic options, we conclude that it is necessary to standardize certain variables—such as the viral clearance time, biomarkers associated with severity, hospital stay, requirement of invasive mechanical ventilation, and mortality rate—in order to facilitate verification of the efficacy of such treatments and to better assess the repeatability of the most effective and promising results.

Coronavirus disease 2019 (COVID-19) induced by the severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2) has impacted the lives and wellbeing of many people. This globally widespread disease poses a significant public health concern that urges to discover an effective treatment. This review paper discusses the effectiveness of repurposed drugs used to treat COVID-19 and potential novel therapies for COVID-19. Among the various repurposed drugs, remdesivir is the only agent approved by the Food and Drug Administration (FDA) to treat COVID-19. On the other hand, several drugs have been listed in the Emergency Use Authorization (EUA) by the FDA to treat COVID-19, including casirivimab and imdevimab, baricitinib (in combination with remdesivir), bamlanivimab, tocilizumab, and IL-6 inhibitors. In addition, in vitro and clinical studies have suggested cepharanthine, sotrovimab, and XAV-19 as potential treatments to manage COVID-19. Due to inadequate understanding of COVID-19 and the rapid mutation of SARS-CoV-2, COVID-19 remains a threat to global public health, with vaccination considered the most effective method to decrease COVID-19 transmission currently. Nevertheless, with the intense efforts of clinical researchers globally, more promising treatments for COVID-19 will be established in the future.