A new phase 1 clinical trial will determine if vaccine candidate, MPV/S-2P, is safe for humans, and may potentially offer protection not seen before in the first-generation of COVID-19 vaccines.
Image Credit: CDC
The National Institutes of Health’s National Institute of Allergy and Infectious Diseases (NIAID) Laboratory of Infectious Diseases announced it was beginning a phase 1 trial for an investigational COVID-19 vaccine, MPV/S-2P, earlier this summer.1 The vaccine uses a live-weakened version of a virus called murine pneumonia virus (MPV), which does not cause disease in humans. The mechanism of action delivers a version of the SARS-CoV-2 spike protein (S-2P) stabilized in its prefusion conformation. Investigators explain the delivery of this vaccine has shown an affinity for epithelial cells that line the respiratory tract and may be effective in delivering vaccine to the places where natural coronavirus infections begin.1
Investigators are moving forward after success in pre-clinical trials. In studies with primates, the vaccine was determined to be safe and well tolerated.1
This is the first NIAID clinical trial to be conducted as part of the Department of Health and Human Services (HHS) Project NextGen. Led by the Biomedical Advanced Research and Development Authority, part of the HHS Administration for Strategic Preparedness and Response, and NIAID, Project NextGen is a coordinated effort between the federal government and the private sector to broaden the pipeline of new, innovative vaccines and therapeutics. Through Project NextGen, NIAID plans to facilitate clinical development of promising next-generation COVID-19 vaccines in phase 1 and 2 trials.1
For the study, investigators are looking to enroll 60 adults, between the ages of 18 to 64 years, who previously received at least 3 prior doses of an FDA-approved or -authorized mRNA COVID-19 vaccine. Study volunteers will be divided into 3 cohorts. Those in the first cohort will receive 1 dose of the investigational vaccine delivered in a nasal spray at the lowest dosage, with enrollees in the next 2 cohorts receiving progressively higher doses. During 7 follow-up visits over about 1 year, investigators will measure how well the vaccine candidate is tolerated, and if it generates an immune response in the blood and in the nose.1
The trial sites include the Baylor College of Medicine, the Hope Clinic of Emory University, and New York University.1
As the COVID-19 variants keep evolving, the existing vaccines have seen the goal and expectation of immunizations going from disease prevention altogether to minimizing disease severity including hospitalizations and mortality rates.
The MPV/S-2P vaccine has produced robust systemic immune responses, including SARS-CoV-2-directed antibodies, as well as local immunity in cells in the mucosal tissues lining the nose and respiratory tract. Studies in humans and animals suggest that mucosal immunity is more effective than systemic immunity in controlling replication of respiratory viruses.1
“While first-generation COVID-19 vaccines continue to be effective at preventing severe illness, hospitalizations, and death, they are less successful at preventing infection and milder forms of disease,” said Jeanne M. Marrazzo, MD, MPH, NIAID director. “With the continual emergence of new virus variants, there is a critical need to develop next-generation COVID-19 vaccines, including nasal vaccines, that could reduce SARS-CoV-2 infections and transmission.”1
And, for those who might be vaccine averse due to anxiety around needles this could potentially be an alternative to get those individuals to take a vaccine that does not require them to roll up their sleeves and receive a subcutaneous injection.
The National Institutes of Health (NIH) has initiated a Phase 1 clinical trial for a new investigational COVID-19 vaccine, MPV/S-2P.
The trial involves 60 adults who have previously received at least three doses of an FDA-approved mRNA COVID-19 vaccine.
If successful, the nasal COVID-19 vaccine could offer an alternative to needle-based vaccines, appealing to those with needle anxiety and potentially benefiting pediatric populations.
Ultimately, if proven safe and efficacious, a future with nasal COVID-19 vaccines could be a reality. One just has to look to the experience of nasal influenza vaccines to glimpse a similar outlook for COVID-19 vaccines.
Another prospective group that could benefit from a nasal COVID-19 vaccine may be the pediatric population. As they might be in the midst of receiving their childhood immunizations, a nasal vaccine may give children a reprieve from another shot in the arm.
Nasal influenza vaccines have been widely studied in this population; although, they have seen mixed recommendations with federal agencies and medical specialty organizations—depending on the individual year.
For example, back in 2016, the Centers for Disease Control and Prevention (CDC) Advisory Committee on Immunization Practices (ACIP) voted against the use of the live attenuated influenza vaccine (LAIV), or “nasal spray,” for the 2016-2017 flu season.2 Conversely, for the 2019-2020 seasonal respiratory season, the American Academy of Pediatrics gave its recommendation to the nasal spray form of the influenza vaccine.3
