by Vaccine Development & Approval Process
The development and approval process for new vaccines in the United States is a long and rigorous one aimed at ensuring both safety and efficacy. On average, it takes between 10-15 years for a new vaccine to go through all stages of testing and approval. Scientists must first conduct extensive research to identify potential diseases or pathogens that could be prevented through vaccination. Once a promising target is identified, researchers work to design and test potential vaccine candidates in the laboratory and in animal models.
If early results are promising, clinical trials in human subjects then begin. Phase 1 trials involve small safety and dosage testing. Phase 2 expands testing to hundreds of participants to further evaluate immunity levels and side effects. Phase 3 trials involve thousands of people and compare disease rates between those who receive the vaccine and those who receive a placebo. If Phase 3 results show the U.S. Vaccine is both safe and effective, vaccine manufacturers can then submit a Biologics License Application to the FDA for review and potential approval. Additional post-licensure monitoring is also required to continue monitoring safety. Only once a vaccine successfully completes this rigorous process can it be licensed for widespread public use in the U.S.
Notable Recently Approved Vaccines
Over the past decade, several important new vaccines have gained approval and been added to recommended immunization schedules in the U.S. The HPV vaccine, first approved in 2006, protects against certain strains of human papillomavirus that cause cancers in men and women. Routine HPV vaccination is now recommended for preteens at age 11-12. The rotavirus vaccine was approved in 2006-2008 for prevention of the most common cause of severe diarrhea in infants and children worldwide. Vaccines against shingles, a painful viral infection caused by reactivation of the chickenpox virus (varicella-zoster virus), were also approved in 2006 and 2017 for adults 50 years and older.
Developing Vaccines for Emerging Diseases
While vaccines exist for many common childhood and adult diseases, there is still ongoing work focused on developing vaccines for emerging infectious diseases. Ebola, Zika virus, and most recently Covid-19 have all highlighted the ongoing need for new vaccines against previously unknown pathogens. When Ebola emerged in West Africa in 2014, there were no approved vaccines. However, clinical trials of candidate vaccines were rapidly initiated and an experimental Ebola vaccine was later approved in 2019 based on trial efficacy rates over 90%.
For the Zika virus outbreak in 2015-2016, multiple vaccine candidates also entered clinical testing within a year. With Covid-19 emerging worldwide in 2020, researchers were able to leverage prior work on SARS and MERS vaccines to speed development of several new mRNA and viral vector Covid vaccines. Emergency use authorization was granted to the first two Covid-19 vaccines in late 2020 just one year after the pandemic began. Continued global health threats underscore how the vaccine pipeline must remain flexible in response to recurring or evolving infectious disease threats.
Barriers to Vaccination & Herd Immunity
While new U.S. Vaccine approvals have led to remarkable increases in coverage, not all recommended immunizations reach their targeted levels nationally due to various barriers. Some parents remain hesitant or refuse certain childhood vaccinations due to (sometimes unfounded) concerns about side effects or links to other conditions. These preferences can lead to undervaccinated communities and diminished herd immunity for vaccine-preventable diseases. Socioeconomic barriers also still impact access, as many adults are not up to date on recommended vaccines due to lack of insurance, availability, or awareness of need. National coverage is also not uniform across all states – exemptions vary as do rates of philosophical objections.
Expanded programs focused on community outreach and education aim to overcome hesitancy and boost rates, especially for vulnerable groups. School-entry laws seek to encourage full immunization, while the Affordable Care Act now covers all recommended vaccines with no out-of-pocket costs to help increase accessibility. With travel and globalization, outbreaks can be rapidly imported, underlining the ongoing importance of national vaccination efforts to forestall both domestic and foreign threats to public health through high community levels of protection.
Scientists continue pursuing vaccines against diseases currently lacking immunization options. These include HIV/AIDS, respiratory syncytial virus (RSV), and malaria, among others. Tuberculosis vaccines are also still needed even as TB rates fall worldwide. Universal influenza vaccines providing long-term, multi-season protection instead of annual shots are also an active area of investigation. Researchers are additionally developing more thermostable vaccines that do not require constant cold chain storage and transport, making distribution in remote locations easier.
Advancing delivery methods including microneedle patches, aerosol breaths, and oral droplets instead of traditional injections could boost participation as well. Tailored, personalized immunization schedules based on individual risk factors, genome sequencing and disease prediction modeling may someday allow for prevention to be targeted to those most likely to benefit. Excitingly, immunotherapies like therapeutic cancer vaccines also represent a new frontier at the intersection of prevention and treatment. Continued scientific progress should yield more tools to combat illness and disability worldwide through the targeted application of safe, effective, and accessible vaccines over the long term.
U.S. Vaccine progress has saved millions of lives, yet more work remains. Promoting uptake, overcoming hesitancy, developing new prevention options and refining delivery will be essential to achieving optimal health protection through vaccination globally in the decades to come. Public health agencies, researchers, policymakers and community stakeholders must collaborate to support this important scientific endeavor and ensure its benefits reach all populations equitably. With continued effort and resources, vaccines will likely continue expanding their ability to control infectious disease into the future.
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1. Source: Coherent Market Insights, Public sources, Desk research
2. We have leveraged AI tools to mine information and compile it
Money Singh is a seasoned content writer with over four years of experience in the market research sector. Her expertise spans various industries, including food and beverages, biotechnology, chemical and materials, defense and aerospace, consumer goods, etc.
