Old drug offers new tricks for fighting cancer
DFMO shows promise at extremely low doses
By Nathan Seppa
SAN DIEGO — A drug once envisioned as a treatment for established cancers might instead help prevent the occurrence of colorectal cancer. Other work suggests the uses for this old drug might extend to a deadly childhood brain cancer.
Scientists first synthesized the drug, DFMO, in 1979, but since then it has developed a reputation as a jack of all trades and master of few. In the 1980s, DFMO showed efficacy in treating African sleeping sickness and eventually got regulatory approval for that use. It also gained clearance as a skin cream to fend off sun-related skin cancer. Otherwise, DFMO seemed to have been lost in the shuffle.
Part of the problem was a curious side effect of the drug. In some patients, it caused subtle, temporary hearing loss.
Now, oncologist Frank Meyskens Jr. of the University of California, Irvine and his colleagues have completed nearly two decades of testing very low doses of DFMO in people who are at high risk for colorectal cancer. Early on, the work showed that at doses only one-fiftieth the amount used to treat cancers, DFMO was safe and patients tolerated it well — and the hearing side effect didn’t show up.