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dactinomycin

n. actinomycin D

Wikipedia
Dactinomycin

Dactinomycin, also known as actinomycin D, is the most significant member of actinomycines, which are a class of polypeptide antitumor antibiotics isolated from soil bacteria of the genus Streptomyces. It is one of the older anticancer drugs, and has been used for many years.

It is on the WHO Model List of Essential Medicines, the most important medications needed in a basic health system.