Updated: Enero 5, 2006
In the United States, candidate vaccines are initially developed by academic investigators, the National Institutes of Health, and by private industry. The decision to further develop and manufacture vaccines, however, occurs largely with the vaccine manufacturers.
Occassionally, as was the case with the new smallpox vaccine, the Federal government contracts to have the vaccine made.Thus vaccine production and availability are usually subject to expected market demand.
The private industry will more likely produce a vaccine that will be used by many people than one that will be used by just a few. Also developing countries cannot afford expensive vaccines.
However, that doesn’t mean that the vaccines needed by a small percentage of the population or for developing countries cannot or should not be created. Many researchers are working on these types of vaccines, including researchers in private industry.
When a vaccine is likely to be targeted to a limited number of individuals in the US, it is called an “orphan vaccine”.
Orphan vaccines are those vaccines for rare infectious diseases or those of narrow scope—for example, diseases limited to particular regions of the world or intended to combat bioterrorism.
Generally, the costs of producing orphan vaccines surpass the potential sales. Therefore, few organizations are willing to develop vaccines for rare diseases when they do not expect to recover the development costs.1
The US Congress enacted the Orphan Drug Act (ODA) which provides incentives for sponsors to develop products for rare diseases. According to the Food and Drug Administration (FDA), more than 200 drugs and biological products for rare diseases have been brought to market since 1983, when ODA was enacted—in contrast, during the decade prior to 1983 fewer than ten such products came to market.2
The ODA defines two classes of orphan diseases:
The incentives stipulated by ODA include a 50% deduction tax credit for clinical trial expenses and a market exclusivity of seven years. Also, because many orphan drugs are for serious or life-threatening diseases, their approval time may be considerably shorter than the approval time for other drugs.
These incentives make it possible for small companies and academic researchers to develop drugs or vaccines that might otherwise not be developed.
“Orphan” drug status is determined by the FDA. The granting of this status does not, however, imply that the vaccine will be developed by the manufacturer. As of 2000, the FDA listed only 8 candidate vaccines that had been designated to have orphan status.
No vaccines developed as an “orphan” vaccine have been licensed.