The U.S. Food and Drug Administration (FDA) earlier today issued a formal announcement that it is investigating the safety of  the multiple myeloma treatments Revlimid and thalidomide. 

The investigation is being carried out due to clinical trial results that suggest Revlimid may increase the risk of secondary cancer in patients taking the drug for extended periods of time.

The announcement confirms a Beacon news update last week that reported evidence that an investigation of Revlimid was underway (see related Beacon ^[1] news).

Today's FDA statement says that the agency is "aware of results from clinical trials ... that have found that patients treated with Revlimid ^[2] (lenalidomide) may be at an increased risk of developing new types of cancer compared to patients who did not take the drug."

For this reason, the FDA "is currently reviewing all available information on this potential risk and will communicate any new recommendations once it has completed its review."

The announcement adds that the FDA recommends that patients now taking Revlimid should continue taking the drug as prescribed by their physician, and that the FDA currently believes "the benefits of Revlimid continue to outweigh the potential risks."

One somewhat unexpected development found in the FDA announcement is news that the agency also is investigating thalidomide ^[3] (Thalomid) and whether it, too, may be linked to increased rates of secondary cancer.  This investigation is being carried out, the FDA said in its statement, because Revlimid and thalidomide are chemically very similar to one another. 

The FDA did not report or suggest, however, that the agency has any evidence at this time that thalidomide may increase rates of secondary cancer in multiple myeloma patients.

In a statement to the Beacon regarding the FDA announcement, a spokesperson for Celgene, the company that markets both Revlimid and thalidomide, said that Celgene "will continue to provide any information needed to complete the [FDA's] review and, as before, will also look toward the presentation of further data at medical meetings this summer."

More data on Revlimid and its potential link to increased rates of secondary cancer are expected to be presented at the upcoming International Myeloma Workshop in May and the American Society of Clinical Oncology meeting in June.

The full text of the FDA announcement is available at the FDA website ^[4]. 

A complete compilation of Beacon articles with information on the Revlimid safety controversy is available here ^[5].