Folkman answered the fall's doubters with a press release that said he remained hopeful his results would be replicated and that the transferring of techniques between laboratories is often painstaking and time-consuming.

At that point, Folkman and NCI formulated a plan for collaboration between researchers from their labs that would speed the process up.

But in another blow for Folkman last Tuesday, BMS--which had contracted to produce one of the drugs Folkman uses in his cancer treatment--pulled out of that agreement.

But one day later, NCI researchers announced that they had been able to reduce tumor size using one of Folkman's drugs, endostatin.

To achieve tumor reduction, Folkman's treatment inhibits angiogenesis, the growth of blood vessels within the tumor. Two of the main drugs used are named endostatin and angiostatin.

While Folkman's strongest results were achieved using a combination of these two drugs, NCI's confirmation regards only endostatin.

This duplication clears the way for what the public has been clamoring for since last May--human trials.

Initially, endostatin will undergo Phase I human trials, meaning that the object will be to determine only its safety and the appropriate dosage schedule.

Very few human subjects will be approved for these trials, and the tumors treated will be restricted to solid masses, such as those found in the breast or colon.

Researchers at the NCI caution against runaway expectations--the time needed to adapt the technique from mice to humans will be considerable.

There are currently more than a dozen compounds in development that hope to treat cancer through similar attempts at inhibition of angiogenesis, all used by different researchers across the country.

As is typical in institutional research, all compounds devised by Folkman become the property of his employer, Children's Hospital.

Both endostatin and angiostatin were licensed to the pharmaceutical company EntreMed, and angiostatin was further licensed to BMS.

In response to BMS's announcement that they would not produce angiostatin, EntreMed's stock plummeted, only to be revived after the NCI announcement one day later.

EntreMed can now attempt to produce angiostatin itself, as it does endostatin, or license it to another company.