Most people don’t realize that, once the FDA approves a drug for a particular use, it can then be prescribed by a physician for an entirely different medical condition. Many of those “off-label” uses start through word-of-mouth information about how a particular drug seemed to help treat different conditions. Sometimes published studies have indicated usefulness of the drug for a condition not studied in the original FDA approval.

Some researchers think there should be a concerted effort to test existing drugs to find those that may help in treating different conditions. As a recent article pointed out, developing new drugs is an expensive and lengthy process, and often the side-effects that are found during the testing will block approval of the drug. But “finding new targets for drugs already in use to treat other disease, in other words repurposing, is an emerging area in developing anti-cancer therapies.” The “old” drugs have already been tested thoroughly for side-effects.

A recent study has found that calcium channel blockers — commonly prescribed for hypertension — can effectively stop cancer metastasis (spread of cancer cells from the original site of the cancer to other tissues or organs). The mechanism by which it does this is related to a very complicated process by which some aggressively spreading cancer cells express a protein called “Myosin-10” which increased the cancer cell motility or movement.

These cancers have a large number of structures that are like sticky “fingers” that allow the cells to sense their environment and to navigate through adjacent tissue. One researcher said it is like a blind spider finding its way through touch. The research found that the calcium channel blockers targeted those “fingers,” making them ineffective and blocking the cell movement.

Much more research is needed to determine which cancers can effectively be treated through using calcium channel blockers. Currently the research is centered on breast and pancreatic cancer. But the findings of the study reaffirm the concept that “repurposing” existing drugs may be a faster and more efficient way of developing new treatments of diseases and conditions.