Pyrogen testing

One pyrogen test is a qualitative biological test based on the fever response of rabbits. If a pyrogenic substance is injected into the vein of a rabbit, a temperature elevation will occur within 3 hours. Many imitative medical agents will also cause a fever. 

Historically, the rabbit pyrogen test constituted the most widely used method. This entails parenteral administration of the product to a group of healthy rabbits, with subsequent monitoring of rabbit temperature using rectal probes. Increased rabbit temperature above a certain point suggests the presence of pyrogenic substances. The basic rabbit method, as outlined in the European Pharmacopoeia, entails initial administration of the product to three rabbits. The product is considered to have passed the test if the total (summed) increase of the temperature of all three animals is less than 1.15 °C. If the total increase recorded is greater than 2.65 °C then the product has failed. However, if the response observed falls between these two limits... 

Hartung, T., Comparison and validation of novel pyrogen tests based on the human fever reaction, ATLA, 30, 49, 2002. 

The United States Pharmacopeia describes a pyrogen test using rabbits as a model (USP, 1995b). This test, which is the standard for limiting risks of a febrile reaction to an acceptable level, involves measuring the rise in body temperature in a group of three rabbits for 3 h after injection of 10 ml of test solution. 

Unless otherwise specified in the individual protocol, inject 10 ml of the test solution per kilogram of body weight into an ear vein of each of three rabbits, completing each injection within 10 min after the start of administration. The test solution is either the product, constituted if necessary as directed in the labeling, or the material under test. For pyrogen testing of devices or injection assemblies, use... 

Wearly, M. and Baker, B. (1977). Utilization of the limulus amebocyte lysage test for pyrogen testing of large-volume parenterals, administration sets and medical devices. Bull. Parenter. Drug Assoc. 31 127-133. 

Manufacturing is performed in cleanroom conditions. Sterilization processes in the form of heat, steam, gas, or radiation are applied to ensure microorganisms are destroyed in the drug product. For protein-based drugs that can be damaged by the normal sterilization processes, the product is manufactured under aseptic conditions. Both sterility and pyrogen tests are performed to ensure parenteral drug products are safe to be injected. 

Especially if sterile preparations are made from nonsterile bulk materials, pyrogen testing should be done at the pharmacy or in a contract laboratory. 

Pyrogen Test No. of Vials Acceptance Criteria X ml Vials/Ampoules... 

Note 1 Separate study should be performed for different loads/sizes. Note 2 Heat penetration and pyrogen test should be performed at beginning, middle, and end of the operations. 

Sterility and pyrogenicity testing. For these tests, samples of eluates were obtained from 7 generators. Samples of the first elution and the final elution (48 hr after heavy clinical use) were obtained from two generators. All samples were... 

Preparations are pyrogen-tested using a Limulus Amebocyte Lysate test kit. 

PW, purified water WFI, water for injection EU, endotoxin units Pyrogen, pyrogen test (qualitative). 

Microbial contamination counts are often determined. Sterility and pyrogen tests are needed for parenteral APIs. 

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