Vaccines play an essential role in keeping communities healthy by protecting against infectious disease. When sufficient people have received their immunization shots, germs no longer spread as easily between those vaccinated and those not immunized – creating what is known as community immunity.
The COVID-19 pandemic spurred vaccine innovation, but without concerted effort this momentum could quickly vanish. Luckily, industry has much to gain by applying lessons learned during this challenging event.
1. Vaccines for Non-Communicable Diseases
Vaccines provide vital protection from millions of infections that would otherwise make us sick, lead to serious complications or even cause death. Their development typically takes 10-15 years, from initial research at university laboratories and companies in the private sector, through preclinical testing and clinical trials.
At this phase, small groups of people receive the vaccine in order to gain more information on its effect in humans, monitor common and less common side effects, and assess whether it can generate an immune response. It may then go forward into larger clinical trials with thousands of participants.
If a vaccine has been determined safe and effective, the Advisory Committee on Immunization Practices (ACIP) at CDC will recommend its use across the United States. Once FDA reviews and approves it, general population use can begin. VAERS and the Vaccine Safety Datalink continue monitoring vaccine safety post-widespread use.
2. Vaccines for Malaria
Malaria is one of the world’s deadliest infectious diseases, killing approximately half a million people every year, predominantly children under five. Scientists have been working for more than 60 years on developing an effective malaria vaccine.
Malaria vaccine development poses several barriers. Notably, licensure requirements necessitating extensive clinical trials drive up development costs beyond what would be sustainable without subsidies from non-governmental organizations and public-private partnerships.
Blood-stage vaccines designed to target merozoites (the parasite’s disease-causing forms) have made significant advances over the last decade. One such blood-stage vaccine, developed by GlaxoSmithKline Biologicals’ RTS,S/AS01 vaccine was given WHO approval on October 6, 2021, leading to its widespread use and significantly reducing malaria infections and episodes in areas with high transmission. These are important steps towards meeting the goal of eliminating malaria altogether.
3. Vaccines for Cancer
Vaccines used to prevent infections work by injecting inactivated or killed viruses or bacteria into the body, priming the immune system to recognize them so when actual infections or bacteria come crashing in, your immune system is ready and able to quickly kill them off.
Scientists are developing vaccines to combat cancer caused by viral infections. So far, four preventive cancer vaccines have been approved by the FDA – two specifically targeting human papillomavirus (HPV) for head and neck cancer prevention as well as one against Hepatitis B virus (HBV).
Therapeutic vaccines for cancer aim to kill tumor cells by inducing antigen-specific immune responses against tumor antigens or neoantigens produced by rapid DNA mutation accumulation of cancer cells. Most cancer vaccines combine with immunotherapy treatments such as CAR T cells or immune checkpoint blockade for maximum impact, but there are some exciting new vaccines in early and late stage clinical trials which promise even greater effectiveness than their predecessors.
4. Vaccines for Immunosuppression
Vaccines have become one of the greatest public health advances of modern times, contributing significantly to countries with comprehensive immunization programs’ impressive declines in child mortality rates. Unfortunately, vaccines cannot guarantee immunity – some diseases still occur among vaccinated populations (even after repeated booster shots), demonstrating the need for further research into why immunity wanes and ways to boost immunological memory.
Most vaccines provide sterilizing immunity through inducing antibodies and T cells that protect against serious disease. Studies conducted on individuals with either inherited or acquired immune deficiency states show that vaccination induces functional antibodies which play a vital role in protecting them against disease.
Immunosuppression can arise from numerous conditions and treatments such as chemotherapy, radiation or immunosuppressant drugs used for disease management or organ transplantation. Because of this, vaccine development for immunosuppressed individuals presents unique challenges.