Programs The Basics of Vaccine Development

Vaccines are preventive medications that protect us from serious infections and their most severe and deadly effects. They are primarily biological substances derived from or are based on an infectious agent, such as viruses, bacteria, protozoa or toxins. The basic underlying principle of vaccines is that exposure of very small amounts of the inactivated or weak infectious agents or their components familiarizes and prepares our immune system to mount a robust response. When our immune cells encounter these agents later in the future, they can fight off these invaders effectively and with ease. There are several types of vaccines and they vary on how they teach and prepare the immune system to fight against the invaders. 

As listed below, CVD researchers are actively engaged and led the entire spectrum (‘bench-to-bedside’) of activities involved in the preclinical development, clinical testing, scale-up and mass production, and distribution of a new vaccine - starting from initial discovery of an infectious agent to the large-scale deployment of a newly-developed vaccine.

• Target selection (antigen discovery): Based on our previous studies and existing knowledge in the literature, CVD scientists select a key part of a protein (antigen) of the infectious agent, whether it is a virus, bacteria or protozoa, as the target for the vaccine. For e.g., for COVID-19 vaccine, we chose the receptor-binding domain (RBD) on the SARS-CoV-2 spike protein as the target since it helps the virus to attach itself to the host receptors and gain entry.
• Vaccine Platform/Technology Selection: At CVD, our decision on which type(s) of vaccine to produce for a particular disease is based on a number of biological, epidemiological and real-world factors such as cost, storage conditions, ease of clinical administration etc. For e.g. Although Hepatitis B occurs in nearly every part of the world, it is more common in certain Asia, Africa, South America and the Caribbean countries. Therefore, we chose yeast-expressed recombinant protein-based platform for this vaccine because it was an effective and proven technology that was already used worldwide for several other vaccines.
• Establishing preclinical evidence of safety and efficacy: We perform extensive robust experiments using animal models to establish robust scientific evidence for the preclinical safety and efficacy of the chosen vaccine candidate. These studies help us understand the potential benefits and uncover any harmful biological reactions or side-effects that may result from these vaccine candidates. They are a critical step in our decision on whether to take a specific candidate further to clinical trial in humans.
• Clinical trials: Vaccines, like other medications, need to undergo extensive clinical testing and close federal regulatory scrutiny before they are made available and administered to the public. CVD researchers assiduously conduct clinical trials and meticulously collect every piece of information regarding safety, efficacy and any potential adverse events arising from the administration of this vaccine in human subjects, which are then submitted to the FDA for further scrutiny and approval. Since vaccines are intended as preventative medicine for otherwise healthy individuals of various age groups and health conditions, they are expected to pass stricter scrutiny and higher quality-control standards. 
• Manufacturing and process development: Given the urgent need for a low-cost, safe and effective vaccine against COVID-19, the Center is actively involved the establishing partnerships with national and international vaccine manufacturers for accelerated timeline for scalable production of large amounts of vaccine, with a short time to market and deployment in the US and abroad.