However, in studies carried out after the clinical efficacy of cyclophosphamide was demonstrated, phosphoramide mustard proved to be cytotoxic in vitro (footnote omitted), but to have a low therapeutic index in vivo. Cyclophosphamide and the related nitrogen mustard–derived alkylating agent ifosfamide were developed by Norbert Brock and ASTA (now Baxter Oncology). Brock and his team synthesised and screened more than 1,000 candidate oxazaphosphorine compounds. They converted the base nitrogen mustard into a nontoxic "transport form". This transport form was a prodrug, subsequently actively transported into cancer cells. Once in the cells, the prodrug was enzymatically converted into the active, toxic form. The first clinical trials were published at the end of the 1950s. In 1959 it became the eighth cytotoxic anticancer agent to be approved by the FDA. Society and culture
The abbreviation CP is common, although abbreviating drug names is not best practice in medicine. Research
Because of its impact on the immune system, it is used in animal studies. Rodents are injected intraperitoneally with either a single dose of 150 mg/kg or two doses (150 and 100 mg/kg) spread over two days. This can be used for applications such as:

The EPA may be concerned about potential human pathogenicity of an engineered microbe when conducting an MCAN review. Particularly for bacteria with potential consumer exposure they require testing of the microbe on immuno-compromised rats. Cyclophosphamide provides a positive control when studying immune-response of a new drug. References
External links
"Cyclophosphamide". Drug Information Portal. U.S. National Library of Medicine.
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