Esteinascidin 743 is a chemical derivative found within the tissue of tunicates. The compound has shown promising results [1] in the treatment of soft tissue sarcoma. What makes it unique is that is effective against a specific type of sarcoma making it more useful than conventional therapies.
In drug form it is known as Yondelis (trabectidin) and produced by PharmaMar who claim that 95,000 lbs of sea squirt harvest only 3 ounces of the chemical but that an effective dose can be made with as little as 0.05 ounces.[2]
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