El plasma de convalecientes como un tratamiento potencial en pacientes con COVID-19 / Convalescent plasma as potential treatment for COVID-19 patients

Introducción: El plasma de convalecientes es una inmunoterapia pasiva que se ha usado para el tratamiento y prevención de muchas enfermedades infecciosas por más de un siglo. Dada la falta de tratamiento específico para el nuevo coronavirus SARS-CoV-2, el plasma de convalecientes es una alternativa terapéutica potencial contra la COVID-19. Objetivo: Realizar una revisión del empleo del plasma de convalecientes como alternativa terapéutica a la COVID-19. Desarrollo: Se empleó la estrategia de búsqueda del tema; consultando las bases de datos Pubmed, SciELO, Lilacs, Cochrane Library y Web of Science. El plasma de convalecientes ha mostrado efectividad en el tratamiento de varias enfermedades virales. Así, la evidencia sobre su uso en los pacientes con COVID-19 es escasa, aunque se han obtenido resultados alentadores, pero no concluyentes por falta de un número mayor ensayos clínicos. Al mismo tiempo, Cuba incluye en sus protocolos de actuación contra la COVID-19 este tratamiento. Conclusiones: Esta alternativa resulta una herramienta inmunoterapéutica en los pacientes con la COVID-19, ya que mejora el estado clínico y disminuir la tasa de letalidad. Sin embargo, se necesitan más ensayos clínicos controlados y aleatorizados que afirmen su efectividad y seguridad(AU)

Introduction: Convalescent plasma is a form of passive immunotherapy which has been used for the treatment and prevention of many infectious diseases for more than one century. Given the absence of a specific treatment for the novel coronavirus SARS-CoV-2, convalescent plasma is a potential therapeutic alternative against COVID-19. Objective: Carry out a review about the use of convalescent plasma as a therapeutic alternative against COVID-19. Discussion: A search was conducted about the topic in the databases Pubmed, SciELO, Lilacs, Cochrane Library and Web of Science. Convalescent plasma has been shown to be effective in the treatment of several viral diseases. However, evidence of its use in COVID-19 patients is scant. Promising results have been obtained, though, but they are not conclusive due to the need of a larger number of clinical trials. In Cuba this treatment is included among the clinical management protocols for COVID-19. Conclusions: This alternative is an immunotherapeutic tool for the treatment of COVID-19 patients, since it improves their clinical status and reduces lethality rates. However, more controlled and randomized clinical trials are required confirming its effectiveness and safety(AU)

In vitro Characterization of Anti-SARS-CoV-2 Intravenous Immunoglobulins (IVIg) Produced From Plasma of Donors Immunized With the BNT162b2 Vaccine and Its Comparison With a Similar Formulation Produced From Plasma of COVID-19 Convalescent Donors.

Despite vaccines are the main strategy to control the ongoing global COVID-19 pandemic, their effectiveness could not be enough for individuals with immunosuppression. In these cases, as well as in patients with moderate/severe COVID-19, passive immunization with anti-SARS-CoV-2 immunoglobulins could be a therapeutic alternative. We used caprylic acid precipitation to prepare a pilot-scale batch of anti-SARS-CoV-2 intravenous immunoglobulins (IVIg) from plasma of donors immunized with the BNT162b2 (Pfizer-BioNTech) anti-COVID-19 vaccine (VP-IVIg) and compared their in vitro efficacy and safety with those of a similar formulation produced from plasma of COVID-19 convalescent donors (CP-IVIg). Both formulations showed immunological, physicochemical, biochemical, and microbiological characteristics that meet the specifications of IVIg formulations. Moreover, the concentration of anti-RBD and ACE2-RBD neutralizing antibodies was higher in VP-IVIg than in CP-IVIg. In concordance, plaque reduction neutralization tests showed inhibitory concentrations of 0.03-0.09 g/L in VP-IVIg and of 0.06-0.13 in CP-IVIg. Thus, VP-IVIg has in vitro efficacy and safety profiles that justify their evaluation as therapeutic alternative for clinical cases of COVID-19. Precipitation with caprylic acid could be a simple, feasible, and affordable alternative to produce formulations of anti-SARS-CoV-2 IVIg to be used therapeutically or prophylactically to confront the COVID-19 pandemic in middle and low-income countries.

Antibody Preparations from Human Transchromosomic Cows Exhibit Prophylactic and Therapeutic Efficacy against Venezuelan Equine Encephalitis Virus.

Venezuelan equine encephalitis virus (VEEV) is a mosquito-borne RNA virus that causes low mortality but high morbidity rates in humans. In addition to natural outbreaks, there is the potential for exposure to VEEV via aerosolized virus particles. There are currently no FDA-licensed vaccines or antiviral therapies for VEEV. Passive immunotherapy is an approved method used to protect individuals against several pathogens and toxins. Human polyclonal antibodies (PAbs) are ideal, but this is dependent upon serum from convalescent human donors, which is in limited supply. Non-human-derived PAbs can have serious immunoreactivity complications, and when "humanized," these antibodies may exhibit reduced neutralization efficiency. To address these issues, transchromosomic (Tc) bovines have been created, which can produce potent neutralizing human antibodies in response to hyperimmunization. In these studies, we have immunized these bovines with different VEEV immunogens and evaluated the protective efficacy of purified preparations of the resultant human polyclonal antisera against low- and high-dose VEEV challenges. These studies demonstrate that prophylactic or therapeutic administration of the polyclonal antibody preparations (TcPAbs) can protect mice against lethal subcutaneous or aerosol challenge with VEEV. Furthermore, significant protection against unrelated coinfecting viral pathogens can be conferred by combining individual virus-specific TcPAb preparations.IMPORTANCE With the globalization and spread or potential aerosol release of emerging infectious diseases, it will be critical to develop platforms that are able to produce therapeutics in a short time frame. By using a transchromosomic (Tc) bovine platform, it is theoretically possible to produce antigen-specific highly neutralizing therapeutic polyclonal human antibody (TcPAb) preparations in 6 months or less. In this study, we demonstrate that Tc bovine-derived Venezuelan equine encephalitis virus (VEEV)-specific TcPAbs are highly effective against VEEV infection that mimics not only the natural route of infection but also infection via aerosol exposure. Additionally, we show that combinatorial TcPAb preparations can be used to treat coinfections with divergent pathogens, demonstrating that the Tc bovine platform could be beneficial in areas where multiple infectious diseases occur contemporaneously or in the case of multipathogen release.