Rokote Laboratories Finland Ltd is probably the only company in Europe developing a nasal COVID-19 vaccine – the administration method brings substantial benefits to combating the disease
The nasal COVID-19 vaccine can suppress the infection before the symptoms even appear. People who are not infected would not spread the disease and the pandemic could come to its end. Rokote Laboratories Finland Ltd is one of the few European companies, if not the only one, developing a nasal vaccine.
COVID-19 morbidity numbers remain high on a global scale. Even though currently available vaccines prevent the severe form of the disease, they have not been able to prevent the spreading of the coronavirus.
“As long as we are unable to keep the coronavirus from spreading, there is a risk of new severe variants of the virus emerging. Moreover, we do not know how reoccurring illness or long covid, impact a person’s immune system. Therefore, it is important to develop a coronavirus vaccine that can prevent individuals from getting the infection and bring an end to the pandemic,” says CEO of Rokote Laboratories Finland Ltd Tuija Keinonen.
The Finnish vaccine development company Rokote Laboratories Finland Ltd is a Kuopio and Helsinki based pharmaceutical company, which is developing a nasal COVID-19 vaccine. The vaccine consists of an adenoviral vector to which the spike protein gene of the SARS-CoV-2 virus has been transferred. The vaccine aims to program the cells of the nasopharynx to produce the SARS-CoV-2 virus spike protein that generates the immune response. The FINCoVac vaccine does not contain the SARS-CoV-2 virus itself.
The nasal vaccine can prevent infection
The administration method of Rokote Laboratories Finland’s vaccine is one of its most important benefits. The vaccine, which is administered into the nose in the form of a spray or drops, is expected to produce sterilizing immunity in the first entry point of the virus in the human body. This enables the virus infection to be suppressed before any symptoms appear.
“The coronavirus typically infects the upper airways or, in other words, the nasopharyngeal mucosa. The purpose of the nasal vaccine is to form a strong immune defence in these mucous membranes to keep the virus from reproducing and prevent the infection. People who do not get infected do not spread the virus,” says R&D Director Erkko Ylösmäki.
The mechanism of action of the available injectable vaccines is different than the nasal vaccines. Injectable vaccines generate in the bloodstream and in the lower airways an immune response mainly based on immunoglobulin G (IgG) antibodies, which provides protection against the severe form of the disease.
“The weakness of injectable vaccines is their inability to form a strong immune defence on the nasopharyngeal mucosa. This enables the virus to reproduce in the nasopharynx of vaccinated individuals, cause symptoms and even spread before the immune system can rectify the situation. The aim of the nasal vaccine is to stop the virus in the first point of entry, specifically on the nasopharyngeal mucosa, by significantly improving the mucosal immunity based on IgA antibodies,” Ylösmäki explains.
Easy administration is a benefit of nasal administration
Injectable vaccines as primary vaccines have been effective particularly in terms of protection against the severe form of the disease. That said, it might be possible to attain more effective protection with a nasal booster after the primary vaccination. As such, the most important benefit of the nasal spray or drop vaccine is expected to be their ability to preventing the spreading of the pandemic, compared to the injectable vaccines. Nasal administration is also painless and therefore more convenient than injection.
“There are still areas and countries in the world that have not even started the first round of vaccinations. In these countries, nasal administration could be an economical, ecological and safer vaccination method – perhaps even the only possible one,” Keinonen says.
Clinical assessment of efficacy is challenging
Even though the benefits of the nasal vaccine are clear, developing it is not easy. The nasal mucosa has evolved to handle pathogens, and the natural defence mechanisms of the nose effectively expel foreign materials from the upper airways. This makes it challenging to get the vaccine’s spike protein gene through the barrier to activate the immune cells in the nasopharynx.
Another development challenge stems from the assessment of clinical correlates of efficacy. In the current clinical trials, the efficacy of nasal vaccines is evaluated using the clinical correlates of efficacy established with injectable vaccines.
“This means that even though the nasal vaccine primarily impacts the amount of mucosal IgA antibodies that neutralise the virus, the current clinical trials correlate the clinical efficacy to the amount of the serum IgG antibodies that neutralise the virus and are primarily affected by the injectable vaccines. Even the authorities are currently unsure as to the kinds of indicators and correlations to use for ensuring clinical efficacy of nasal vaccines,” Ylösmäki describes.
According to the view of the European Medicines Agency EMA, the nasal vaccine must undergo phase III efficacy studies if a correlation with the effects of approved vaccines cannot be demonstrated.
Europe’s vaccine self-sufficiency brings security
On a global scale, roughly 50 mucosal COVID-19 vaccines are under development, 20 of which are in the clinical phase. According to the Mucosal Vaccines for SARS-CoV-2: Scientific Gaps and Opportunities workshop (11/2022) organised by NIAID (19, BARDA (2), BMFG (3), The Wellcome Trust and CEPI (4), Rokote Laboratories Finland Ltd is currently the only European pharmaceutical company developing a nasal vaccine. This is significant in terms of Europe’s vaccine self-sufficiency and emergency supply.
“There are three nasal vaccines in the world that have been granted marketing authorisation. We do not know when they will be authorised in Europe if applications are submitted or whether authorisation will even be granted upon applications. The coronavirus has proven its adaptability and virulence many times over, and the world will not be able to manage with one or two vaccines. Nasal vaccines will also be needed to prevent new virus epidemics, and that also motivates us to continue our groundbreaking development work,” Keinonen says.
Upon release into the market, Rokote Laboratories Finland’s vaccine will be as up to date as possible in terms of variant coverage. The clinical trials of the vaccine is planned to begin in 2023.
1 NIAID: National Institute of Allergy and Infectious Diseases
2 BARDA: Biomedical Advanced Research and Development Authority
3 BMFG: The Bill and Melinda Gates Foundation
4 CEPI: Coalition for Epidemic Preparedness Innovations
CEO, Rokote Laboratories Finland Oy
p. 050 555 1541
Research and Development Director, Rokote Laboratories Finland Oy
p. 040 5836604
Text: Anni Turpeinen