FDA Finalizes Guidances For Pandemic and Seasonal Influenza Vaccines

The US Food and Drug Administration (FDA, Rockville, MD, www.fda.gov) has issued final recommendations for increasing the supply of safe and effective influenza vaccines for both seasonal and pandemic use. FDA’s goal with the guidances is to outline the regulatory pathways for the rapid development and approval of these products.

In March 2006, FDA issued two draft guidance documents for public comment-one for seasonal influenza vaccines and another for pandemic influenza vaccines. The draft documents outline specific approaches for manufacturers to develop new vaccines that are safe, pure, and potent. The final guidances reflect public input, including vaccine companies and public health officials.
 
The guidances describe conventional and accelerated approval pathways to vaccine licensure. Companies selecting the conventional pathway must provide clinical evidence that the vaccine prevents influenza. Adequate and well-controlled clinical trials are also required for accelerated approval, but companies may use a biological indicator-such as immune response to the vaccine-to predict effectiveness, an approach that may reduce the vaccine’s development time. Further clinical studies are then required to verify the vaccine’s clinical benefit.

Both guidances recommend using recent technologies such as cell culture and recombinant manufacturing to enhance the development and evaluation of vaccines. They also recommend adding substances that improve the immune response from the vaccine (novel adjuvants).

The guidances indicate that manufacturers should submit a new biologics license application (BLA) for the initial licensure of a pandemic or seasonal influenza vaccine to ensure that each pandemic and seasonal vaccine has its own trade name and labeling.

For companies with US-licensed seasonal influenza vaccines, the pandemic guidance outlines the regulatory pathway for obtaining licensure for a new pandemic vaccine in which the manufacturing process is the same as for the seasonal vaccine. For manufacturers developing vaccines using a new manufacturing process, both guidance documents explain the process for obtaining licensure using the accelerated approval pathway.

The guidance documents represent the FDA’s ongoing efforts under its Critical Path Initiative to translate scientific advances, such as cell-culture derived and recombinant vaccine technologies, into new medical products with shorter approval timeframes.