(CNN) Earlier this year, the Food and Drug Administration took the rare step of pressuring a drug company to stop selling an opioid painkiller that was widely abused. But as CNN recently reported, before it halted sales of Opana ER, Endo Pharmaceuticals cut a deal with a competitor to split profits on a generic version of the drug still on the market.

The head of the FDA, Scott Gottlieb, reacted on Friday announcing that his agency is reviewing data and will decide whether to take action on other versions of the drug.

"I recently have seen media reports stating that Endo is participating in a re-launch of the old version of Opana ER," he told reporters in a speech at the National Press Club in Washington.

The FDA determined this summer that the risks of Opana ER outweighed the benefits.

Endo voluntarily withdrew the original version of Opana ER in 2012, arguing that the drug was susceptible to abuse. But before it stopped selling the original version, Endo replaced it with a new version of Opana ER with a hard coating that made it harder to crush and snort.

Drug abusers, however, quickly learned how to melt the new crush-resistant pill and inject it. Opana ER is more potent than either oxycodone or morphine. Abusers told researchers they preferred the drug because the high was so intense.

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