Entos Pharmaceuticals Passes Significant Enrollment Milestone in Phase 2 Clinical Trial of its COVID-19 DNA Vaccine

Entos Pharmaceuticals (Entos), a clinical-stage biotechnology company developing genetic medicines with its Fusogenix proteolipid vehicle (PLV) nucleic acid delivery platform, and Centre National de Recherche et de Formation sur le Paludisme (CNRFP), the Burkina Faso site team lead by Dr. Gansane Adama, announced today that enrollment is now complete into the single and two-dose cohorts of the Phase 2 clinical trial of Covigenix VAX-001-1b (Covigenix), its COVID-19 DNA vaccine. A total of 268 participants are enrolled in the study at two sites in Burkina Faso. The phase 2 trial in Burkina Faso is managed by Clinical Pharma Solutions Inc. based in Ontario, Canada.

"We're thrilled that recruitment for our Phase 2 trial of our COVID-19 DNA vaccine was completed so quickly by Dr. Adama's team in Burkina Faso. We'd like to extend our deepest gratitude to all the study participants, without whom, this milestone would not be possible," said John D. Lewis, Ph.D., founder, and CEO of Entos Pharmaceuticals. "The continued progress of our Covigenix vaccine clinical development program brings us closer towards providing a potentially effective and safe fridge-stable, single-dose vaccine against COVID-19 to under-vaccinated regions of the world."

Formulated using Entos' Fusogenix PLV delivery platform, Covigenix is a DNA vaccine encoding SARS-CoV-2 Spike protein and two genetic adjuvants engineered to stimulate the adaptive and innate immune systems. By stimulating both arms of the immune system, the vaccine is designed to provide effective and durable protection against COVID-19. Preclinical studies of Covigenix demonstrated potent immunogenicity, conferring protection from infection with SARS-CoV-2 in animal models. Given the high stability of DNA, Covigenix has the key advantage of stability for more than a year at normal refrigerated temperatures, making it more cost-effective to store, transport, and deploy to developing countries compared to approved vaccines.

The ongoing Phase 2 trial was preceded by a first-in-human Phase 1 study conducted in Canada. In Phase 1, Entos' Fusogenix PLV platform was determined to be safe and well-tolerated for the intracellular delivery of DNA, with the potential to promote positive immunological outcomes in a single vaccine dose. The ongoing Phase 2 randomized, observer-blind clinical trial in Burkina Faso is further evaluating the safety, tolerability, and immunogenicity of Entos' single-dose and double-dose regimens of the intramuscularly administered Covigenix DNA vaccine candidate in healthy adults 18 or older.

"Despite the availability of mRNA-based vaccines, COVID-19 is still a major problem in Burkina Faso and other countries with vulnerable populations," said Dr. Gansane Adama, Principal Investigator with CNRFP. "We need vaccines that are safe, effective, and easy to transport, store, and administer. With the study now fully enrolled, we look forward to generating data that can inform the potential utility of this important investigational vaccine."

For more information about Entos and its COVID-19 vaccine visit https://www.entospharma.com/#covid.

About Entos Pharmaceuticals Inc.

A new reality in genetic medicine lies ahead, one that will be ushered in with the advent of safe, effective, and redosable nucleic acid delivery technologies. At Entos, we develop next generation genetic medicines using our proprietary Fusogenix proteolipid vehicle (PLV) drug delivery system. Fusogenix PLVs are formulated with FAST proteins to enable the delivery of nucleic acid into target cells through direct fusion. For more information, visit www.entospharma.com, or follow Entos on Twitter or LinkedIn.

About CNRFP

The Centre National de Recherche et de Formation sur le Paludisme (CNRFP) is a research institution from the National Public Health Institute and funded by the Ministry of Health of Burkina Faso since 1983, as a need to foster quality research that will contribute to evidence-based decision making for the policymakers in Burkina Faso. The institution has its main offices in Ouagadougou, the capital city of Burkina Faso. The CNRFP has developed two research stations, located in Banfora (Clinical Research Unit of Banfora) and Sapone (Clinical Trial Centre of Balonghin), well-equipped to undertake clinical trials at any phase, compliant with national and international regulations.

The research platforms from CNRFP made contributions to the development of vaccines candidate (malaria, Ebola, Covid-19) and antimalarial drug development with support and funds from the Ministry of Health and international partners. For more information, visit the website www.cnrfp.bf

Forward Looking Statements

This press release contains forward-looking statements, within the meaning of Section 21E of the Securities Exchange Act of 1934, as amended and forward-looking information under applicable Canadian securities laws (such forward-looking statements and forward-looking information are collectively referred to herein as "forward-looking statements"). Forward-looking statements contained in this press release include statements regarding Entos' belief as to the mode of action and potential and benefits of Fusogenix proteolipid vehicle platform; the mode of action and potential and benefits of Covigenix VAX-001-1b (Covigenix) as a COVID-19 vaccine; Entos' plans to advance towards a phase 3 study for COVID-19; and other statements related to anticipated developments in Entos' business and technologies. In any forward-looking statement in which Entos expresses an expectation or belief as to future results, such expectations or beliefs are expressed in good faith and are believed to have a reasonable basis, but there can be no assurance that the statement or expectation or belief will be achieved. Such forward-looking statements involve known and unknown risks and uncertainties, which could cause Entos' actual results to differ materially from those in the forward-looking statements. Such risks and uncertainties include, among others, the availability of funds and resources to pursue research and development projects, the efficacy of Fusogenix as a nucleic acid delivery vehicle, the efficacy of Covigenix as a COVID-19 vaccine, the success and timely completion of clinical studies and trials, Entos' ability to successfully commercialize Covigenix, uncertainties related to the research and development of pharmaceuticals, uncertainties related to the regulatory process and general changes to the economic environment. In particular, we may be impacted by business interruptions resulting from COVID-19 coronavirus, including operating, manufacturing supply chain, clinical trial and project development delays and disruptions, labour shortages, travel and shipping disruption, and shutdowns (including as a result of government regulation and prevention measures). It is unknown whether and how Entos may be affected if the COVID-19 pandemic persists for an extended period of time. We may incur expenses or delays relating to such events outside of our control, which could have a material adverse impact on our business, operating results, and financial condition. Investors should consult with the Canadian and U.S. securities commissions for additional information on risks and uncertainties relating to the forward-looking statements. Investors are cautioned against placing undue reliance on forward-looking statements. The Company does not undertake any obligation to update these forward-looking statements, except as required by applicable laws.