CytRx Corp. shares jumped Monday after the drug developer said its experimental treatment for breast cancer caused a “dramatic destruction” of implanted tumors in an animal model.

The Los Angeles company, which does not yet have a product on the market, said tumors in animals treated with its INNO-206 shrank to about one-half their initial volume by the end of 43 days.

INNO-206 is known as a prodrug, a compound converted by the body into the active ingredient of another drug in this case doxorubicin. Doxorubicin is widely used to treat breast, ovarian and lung cancers but has significant side-effects as currently administered.

CytRx acquired INNO-206 through its acquisition of Innovive Pharmaceuticals last September. It has the potential to become “a multi-billion dollar drug,” said Chief Scientific Advisor Joseph Rubinfeld, an Amgen Inc. co-founder, in a statement.

Rodman & Renshaw analyst Simos Simeonidis agreed, telling clients that the drug could be a big seller if it is proven to be just as effective as doxorubicin but much less toxic.

CytRx shares closed up 11 cents, or 11 percent, to $1.09 on the Nasdaq after earlier hitting a 52-week high of $1.24.