The availability of highly effective vaccines against SARS-CoV-2 marks a great advancement in combating the COVID-19 pandemic. Nonetheless, there is still an unmet need for antiviral medication. Firstly, effective and affordable antiviral agents specifically for the treatment of COVID-19 are required. Secondly, broad-spectrum antivirals that are effective against multiple forms of a virus family must be developed in preparation for future pandemics.
This is the message from the German National Academy of Sciences Leopoldina in their ad hoc statement "Antivirals against SARS-CoV-2: current situation and approaches to improved preparation for future pandemics", which is now available in English. In the publication, the scientists explain why antiviral agents are needed, how these can be discovered and developed, and what kind of organisational structures this requires.
Once the pandemic subsides and the virus continues to circulate endemically amongst parts of the population, specific antiviral agents to treat SARS-CoV-2 will continue to be crucial. The virus may cause more severe disease in unvaccinated persons, in persons who have not built up sufficient immunity, even after multiple vaccine doses, and in people in whom vaccine efficacy drops after some time. Ideally, any medication should be easy to administer, effective and affordable. "The few existing medications against SARS-CoV-2 do not suffice. Highly effective agents that can be used as early as possible after infection are important to stop viral replication and disease progression as well as pathogen transmission," states chemist and virologist Helga Rübsamen-Schaeff, speaker of the working group and member of the Leopoldina. Furthermore, antiviral agents are required on a global scale. Readily available medications, which can be inhaled or administered orally, are urgently needed in those regions of the world where access to vaccines and medical infrastructure is limited.
The COVID-19 pandemic highlights the importance of better preparedness for newly emerging pathogens. "Antiviral agents should not only be developed once a new virus has become pandemic. It should be vigorously pursued in advance," says virologist Ralf Bartenschlager, also a speaker of the working group and member of the Leopoldina. Broad-spectrum antivirals ‒ a class of compounds, which are effective against as many different variants of a virus family as possible ‒ are important in this context. One approach is to target those viral structures and functions, which rarely change. Other approaches include targeting cellular factors such as virus binding sites on human cells as well as agents that stimulate the immune system, thereby increasing resilience against a viral infection.
Better pandemic preparedness requires increasing both fundamental research and translational research activities, which support the transition into clinical practice and development of broad-spectrum medication against viruses, which could potentially cause a pandemic. The working group recommends establishing an organisational structure that allows essential infrastructure networks to form. It also suggests cooperation between academic institutions and biotechnology and pharmaceutical companies. Representatives of research institutions, of regulatory authorities and policy makers should form part of such a network to make effective therapies available faster ‒ particularly in emergency situations.
Academia needs to provide a coordinated research infrastructure to promote translation into clinical practice. The working group states that Germany still lacks structures for early-stage pilot and feasibility studies and also for large clinical studies. The experts recommend that test centres, outpatient care, public healthcare services, care facilities and university outpatient departments form networks.
The working group also suggests more effective epidemiological monitoring of circulating virus strains as well as their pandemic potential. This could be achieved by providing public healthcare services with better access to sequencing capacity and sequencing databases, enabling timely detection of emerging virus variants and monitoring their spread.