EXOCOVAC
EXOCOVAC
Exosomes containing immunogenic viral peptides from COVID-19 patients as a new vaccine against Sars-CoV-2.
Under development by Innovex Therapeutics S.L.,
in cooperation with ISGlobal - Barcelona Institute for Global Health and IGTP, the Research Institut Germans Trias i Pujol, and The IrsiCaixa AIDS Research Institute
EXOCOVAC
Innovex developed a novel vaccine platform based on exosomes. Exosomes are extracellular vesicles, or small bubbles, released from cells that act as shuttles for genetic information, proteins and messenger RNA to other cells. The platform features a novel antigen-determinant discovery technology that has been shown to elicit specific IgG (antibody) responses. Moreover, the vaccine platform in question has shown that there are long-lived, non-exhaustive effector T-cell responses.
T cells can be activated to kill infected cells after recognizing antigens. After the pathogen is eliminated, most effector cells will be removed. A small portion of long-lived T cells remain and those can respond rapidly upon pathogen exposure. The asset has been IP protected.
Innovex will test the hypothesis that viral peptides, which are short chains of amino acids, contained in plasma-derived exosomes from Covid-19 patients contain novel immunogenic sequences that upon immunization of mice will induce long-lasting protection against SARS-CoV-2. The type of mice immunized are hACE2 transgenic mice, which are optimized for studies related to the novel corona virus.
Developing an exosome vaccine: "High risk may bring high gain”
our insight of the week - October 20, 2020
Prof. Hernando Del Portillo MD, photo ICREA
Hernando Del Portillo was working at a malaria vaccine at Innovex when the Covid-19 pandemic hit Asia, then Europe, and soon after the rest of the world. Struck by how severe Spain was affected by the new coronavirus, Del Portillo wanted to find out if what he was working on against malaria could also be used for a Covid-19 vaccine. “Due to the emergency of the situation, we needed to act fast”, Del Portillo explains on video call from his office in Barcelona.
Innovex is developing a new platform for vaccine development which is based on small vesicles that all of the body’s cells secrete, called exosomes. They act as a shuttle for genetic information, proteins and messenger RNA to other cells. A few years ago, it was discovered that these exosomes are also able to present antigens and could possibly be used in vaccine development.
Del Portillo immediately started to gather funding for the project – now called Exocovac – and put together a small, but interdisciplinary team, including the virologist Javier Martinez-Picado and the clinician Dr. María Jesús Pinazo. She started collecting samples from Covid-19 patients as early as April, the most acute time of Covid infections in Spain. “We were able to strike at the peak of the pandemic because we acted very fast”, Del Portillo says. From those samples, the team selected 60 patients with different clinical symptoms.
Barcelona, Eixample, hometown of Innovex, photo adobe stock
In humanized mouse models Del Portillo wants to demonstrate that immunizing with exosome cells containing the receptor of the virus will protect them against the virus. With the right formulation, the exosome cells vaccine could induce both antibodies and T-cell responses.
Even though there are multiple vaccine studies currently trying to do just that, Del Portillo has high hopes for the exosome research. “We don’t know if it will be successful, but it is certainly worth investing in. High risk has high gain”, Del Portillo says. “And I think any vaccine effort against Covid-19 is absolutely welcome”, he adds.
Currently the number of infections is increasing again in Spain and other European countries. “Unfortunately, we are witnessing the next peak”, says Del Portillo. “We will try to increase the sample number and include current acute cases as well.”
The next steps require more funding so that by June next year, the proof of concept in the preclinical trial with humanized mouse models will be verified and the process can move on to clinical trials. This is the time frame that Del Portillo is hoping for. “If everything works out, we want to speak to other companies” Del Portillo says, explaining that it would be imperative and sensible to share and capitalize on the research results . “We should accelerate the vaccine development against Covid as much as possible.”