Takeda cancer drug slows tumor growth in mice

An experimental cancer drug made by Takeda Pharmaceutical Co showed signs of slowing tumors growth in mice and has advanced to early human trials, company researchers said Wednesday.

The drug, developed by Takeda’s recently acquired Millennium Pharmaceuticals unit, suppressed tumor cell growth in human lung tissue that had been transplanted into mice, the company reported in the journal Nature.

Teresa Soucy, a Millennium researcher in Massachusetts who led the study, said her team has tested the drug in several different types of tumors in mice.

“We’ve always seen at least tumor growth inhibition, and in some cases, regression—in some cases they get smaller,” Soucy said in a telephone interview.

The drug, called MLN4924, is similar to the company’s blood cancer drug Velcade but targets a different enzyme called the NEDD8-Activating enzyme, which regulates proteins cancer cells need to grow and survive.

Soucy said the new drug works by blocking an early step in the regulation of how certain proteins are broken down.

“We’ve blocked their degradation,” she said, which is causing DNA to “oversynthesize” or replicate.

“It can’t stop. What ends up happening is the DNA gets damaged and the cells die. It was an unexpected finding,” she said.

Soucy said Velcade works in this same basic pathway, but at a later stage. She said the new drug may be more selective than Velcade and could have fewer unwanted side effects, but that has to be proven.

“With Velcade, it does have neuropathy. People feel tingling in their fingers when they take it,” she said.

She said one potential reason for that is the buildup of unwanted proteins in brain cells. Soucy said the new compound theoretically could address some of these issues.

Takeda is currently studying the molecule in several early clinical trials in humans in solid tumors and blood cancers.

“The compound is very well tolerated in mice. We just have to see in humans. It has potentially different clinical efficacy. We just don’t know yet,” Soucy said.

Johnson & Johnson co-develops Velcade, which is known generically as bortezomib.

By Julie Steenhuysen
CHICAGO (Reuters)