While some are still in the clinical trial stage, the following vaccines are currently available: Pediarix is a combination vaccine that combines the immunizations for Diphtheria, Tetanus and acellular Pertussis (DTaP), Hepatitis B and inactivated Polio (IPV), which used to require three separate shots. Pediarix is given to children as a three dose series at 2, 4, and 6 months. So instead of 9 shots for the series to get protection against Diptheria, Tetanus, Pertussis (Whooping Cough), Hepatitis B and Polio, you can now get the same protection for your kids in just 3 shots.
In all clinical trials, the typical process starts with a screening period. The screening period starts with the signing of the informed consent. During the screening period, inclusion/exclusion criteria for the study participation will be checked / tested. Subjects who meet all inclusion criteria and do not meet any exclusion criterion will be eligible to be randomized (in randomized trial) or to be dosed (in non-randomized trial).
The objective of clinical trials is to test new therapies to determine if they have an acceptable level of safety and demonstrate a clinical benefit in helping patients with the disease they targets. If a new treatment is proven to work, then patients in the study would be the first to benefit from it. That said, there is no guarantee that any clinical study will be successful. Requirements for clinical trials are strictly managed by the Food and Drug Administration.