Two decades ago, the influenza vaccine market consisted of 2 manufacturers and was unattractive for new entrants, thereby limiting excess supply capacity. In 2005, the US market experienced a supply failure and subsequent loss of approximately half of available vaccines as well as an outbreak of H5N1 avian influenza, a strain with pandemic potential. These events exposed vulnerabilities in the influenza market and supply chain, and galvanized public and private stakeholders to address the issue.

Market dynamics alone were not enough to support increased investment and capabilities for seasonal and pandemic influenza. A multi-stakeholder approach, including public-private partnerships between the US government and vaccine developers, was needed to advance flu vaccine innovation and build surge capacity in the event of a pandemic and continues today.

The launch of a novel COVID-19 vaccine will be a significant public health tool in response to this current pandemic, but the investments are considerable and public expectations high. To ensure availability of COVID-19 vaccines in the US through both the acute pandemic response phase and, if needed, the post-pandemic phase, partnerships and long-term strategies should be considered now to support capabilities and a sustainable market.

The US government and vaccine developers strengthened the influenza vaccine market by increasing demand for seasonal influenza vaccines and fostering innovation and pandemic preparedness through the following approaches:

• Expansion of the seasonal influenza vaccine market: The cornerstone of pandemic influenza capacity is a robust seasonal influenza market. Efforts to expand access to and uptake of seasonal influenza vaccines in the US population have allowed for investments in infrastructure and capacity that can be rapidly converted to pandemic influenza production, if needed. Further, new products were developed and launched, including quadrivalent vaccines providing protection against 4 influenza strains, high-dose vaccines and adjuvanted vaccines for older adults, and cell-based and recombinant vaccines. The net result of these efforts was 2-fold: introducing more product options in the seasonal influenza vaccine market and building pandemic response capacity that could leverage enhanced antigen production, dose-sparing technologies, and a range of manufacturing processes. These developments might not have occurred without a multi-stakeholder approach and government intervention.
• Public-private partnerships: Advancement in pandemic capability, product innovation, and surge capacity was supported by significant investment from the US government and other stakeholders. The Biomedical Advanced Research and Development Authority and the National Institutes of Health have supported development of next generation influenza vaccine technologies with the goal of improving efficacy and duration of protection and reducing production timelines. The administration recently recognized the importance of these technological advancements in its executive order “Modernizing Influenza Vaccines in the United States to Promote National Security and Public Health.” The US government has also supported pandemic preparedness through stockpiles of bulk influenza vaccine product and the establishment of the Centers for Innovation in Advanced Development and Manufacturing, public-private partnerships that provide domestic surge manufacturing capacity.

With significant investments being made by companies, the US government, and other entities in the expedited development of vaccines and therapies for COVID-19, a dialogue regarding how capacity can be built and maintained in the near and potentially long term to address the current public health threat may be warranted.

Specifically, a set of targeted strategies will help facilitate the US response to the COVID-19 pandemic and ensure long-term preparedness for COVID-19 and other emerging pathogens:

• Promoting public-private partnerships with US leadership: In order to meet the likely demand for the COVID-19 vaccine, new and sustained public-private partnerships will help meet the short-term challenge and ensure preparedness going forward. Continued pursuit of COVID-19 vaccine candidates after the first viable candidate is licensed can help create a stable supply of vaccines to meet population needs. These partnerships should consider R&D costs, IP protections, production needs, and an acceptable ROI for all parties.
• Supporting the shift from pandemic response to broader immunization: Specific attention should also be paid to the post-acute phase of COVID-19 vaccine demand, given the high possibility that COVID-19 may become endemic. Though the initial response is focused on control of the pandemic, reduction in mortality, and economic recovery, herd immunity becomes a consideration immediately thereafter. Rapid deployment is likely to prioritize at-risk populations such as healthcare workers and vulnerable cohorts and could be facilitated through federal purchase of doses under an emergency use order. However, planning for a later phase of broader vaccination will shape decisions related to vaccine manufacturing capacity. The implementation of a post-pandemic market environment and infrastructure will require a shift to broader, sustained preparedness and will involve purchasing on behalf of commercial payers, Medicaid, and Medicare. Channels of vaccine distribution will depend upon specific COVID-19 epidemiology and timing of vaccine availability.

While analyzing the evolution of the influenza vaccine market over the last 20 years may be an imperfect comparison and more work is still needed in that area, the assessment may offer lessons on the longer view for COVID-19 vaccines. Public-private collaboration in response to the 2005 influenza supply and pandemic crisis highlighted seasonal influenza vaccination as an efficient way to build capacity in the event of future pandemics, as well as the importance of targeted investments in antigen production, manufacturing technology, and additional US-based capacity. Lessons learned on building sustainability in the influenza vaccine market may provide guidance on how we ensure COVID-19 vaccine response capability in the long term.