21 CFR § 680.2 - Manufacture of Allergenic Products.
(a) Extraneous allergenic substances. All manufacturing steps shall be performed so as to insure that the product will contain only the allergenic and other substances intended to be included in the final product.
(b) Cultures derived from microorganisms. Culture media into which organisms are inoculated for the manufacture of Allergenic Products shall contain no allergenic substances other than those necessary as a growth requirement. Neither horse protein nor any allergenic derivative of horse protein shall be used in culture media.
(c) Liquid products for oral administration. Liquid products intended for oral administration that are filled in multiple dose final containers shall contain a preservative in a concentration adequate to inhibit microbial growth.
(d) Residual pyridine. Products for which pyridine is used in manufacturing shall have no more residual pyridine in the final product than 25 micrograms per milliliter.
(e) [Reserved]
(f) Records. A record of the history of the manufacture or propagation of each lot of source material intended for manufacture of final Allergenic Products shall be available at the establishment of the manufacturer of the source material, as required by § 211.188 of this chapter. A summary of the history of the manufacture or propagation of the source material shall be available at the establishment of the manufacturer of the final product.