Vaccines - CDC Process

VaccineXpress: Installment 2

Anya Aggarwal, Johns Hopkins University

The VaccineXpress articles are released as a series explaining the process by which the CDC manages distribution of vaccines through interactions with vaccine providers and a whole chain of other key players in the healthcare industry.

The first installment provided a foundation by discussing the basic structure of the vaccine database and explaining key components of vaccine labeling. 

In this installment we will dive into the specifics of the process by which the CDC updates and maintains the vaccine database. We will explore the following questions: What is the process for manufacturers? How does the CDC ensure data submitted from the manufacturer is correct? How does the CDC notify the public when they make updates to the database? 

As discussed in the previous installment, VTrcks (Vaccine Tracking System) is a database of information regarding the publicly-funded vaccine supply chain that allows maintenance and regulation of purchasing, ordering, and distribution. The CDC works with various vaccine manufacturers who participate in VTrcks. Some of these manufacturers include: GlaxoSmithKline, MedImmune, Merck, Novartis/GSK, Pfizer/Wyeth, Sanofi Pasture, and Seqirus. Under The Drug Listing Act of 1972, these manufacturers are legally required to provide the Food and Drug Administration (FDA) with an updated list of all of their manufactured, propagated, compounded, or processed drugs and vaccines set for commercial distribution. Each of these drugs is given a universal identifier called a National Drug Code (NDC). For more information on National Drug Codes (NDC) see installment 1 (Link)

The FDA then uses the information listed and registered with the NDC to classify the drug and update the NDC Directory. In the past, the updating process occurred twice a year which later shortened to once a week, but has now become more frequent since 2013, updating daily. FDA processing and updating using the NDC and listed information is another checkpoint in ensuring the Drug Listing Act of 1972 is enforced and creates accountability in accuracy for the FDA, CDC, and vaccine manufacturers. See National Drug Code Directory

Once the information is submitted, only “final marketed drugs” are subject for review, approval, and appendage to the official NDC Directory.  According to the FDA, an unfinished drug refers to a chemical product that has one or more active pharmaceutical ingredients, but is not a fully functional drug. There are files that detail product listing data for unfinished drugs such as those classified under Active Pharmaceutical Ingredients (API), but these drugs will not be subjected to review by FDA, and therefore all products in these listings are considered unapproved. On the other hand, in the official NDC Directory where all products are finished, some are approved while others are not. It is important to note that simply assigning a finished drug an NDC and submitting it to the Directory does not indicate FDA approval. However, all finished drugs are eligible for review and eventual approval under FDA standards. See NDC Unfinished Drugs Database

In order to submit a drug for review, manufacturers are now required to complete online listing forms (SPL), rather than the previous paper-form method. These forms should include the NDC as well as other listing information about the drug such as: Product Type Name, Marketing Category Name, Pharmacologic Class, and DEA Schedule. Under the Listing Act, this online form must be completed for every new finished drug that is manufactured for commercial distribution. In general, it takes about 10-15 years to develop a new vaccine. During this time, companies work closely with the CDC and FDA to ensure proper development, testing, regulation, and information dissemination. The forms are required twice a year, in June and December, but information in the NDC Directory is updated daily. Since the database is updated daily, the CDC need not spend many resources on informing the public that a database change has been made, since these changes happen routinely everyday.

When listing drug data and updating the database, FDA and CDC do their best to ensure that the information is accurate and current. However, errors and lags in informational updates can occur, so the FDA requests users who recognize any errors to contact the organization immediately. FDA has said they are committed to providing as accurate information as possible, and along with user corrections, the organization encourages manufacturers to fill out another SPL that provides corrective information on products already in the database. These efforts help the CDC ensure data submitted from the manufacturer is correct.