FDA lets Lilly's long-acting Zyprexa off the hook in patient deaths

The FDA says it won't recommend new limits on Eli Lilly ($LLY) schizophrenia med Zyprexa Relprevv after almost a year of investigating the deaths of two patients 3 to 4 days after they received injections.

The agency finished reviewing a study designed to determine why the two patients had extremely high levels of Zyprexa Relprevv in their blood. According to an FDA safety alert, the study suggested much of the increase in drug levels could have occurred after death.

But the results of the study were "inconclusive," the agency said. "FDA is unable to exclude the possibility that the deaths were caused by rapid, but delayed, entry of the drug into the bloodstream following intramuscular injection," the safety alert stated.

This is not the first time Lilly has faced safety issues tied to its Zyprexa franchise. Zyprexa Relprevv's label warns of the risk of "post-injection delirium sedation syndrome," which is caused when the drug enters the blood too quickly. And once-daily Zyprexa came under fire after years of reports of weight gain linked to the med. Lilly dealt with thousands of lawsuits from patients claiming the drug caused them to develop diabetes, but resolved most of them in a $1.2 billion settlement.

The FDA's latest decision could help Lilly continue to eke sales out of its Zyprexa franchise. Since the blockbuster Zyprexa pill went generic, Zyprexa Relprevv has struggled to even partly fill its predecessor's shoes. Lilly doesn't itemize sales for the injectable med, and the franchise brought in worldwide sales of $1 billion last year--a 13% drop from 2013. Still, Zyprexa Relprevv's key patent does not expire until 2018, leaving some room for growth.

Meanwhile, Lilly faces competition from other drugmakers vying for a piece of the schizophrenia market, which is forecast to grow from $5.9 billion in 2013 to $6.4 billion in 2017 as new products launch. Lundbeck and Otsuka have their own once-a-month antipsychotic, Abilify Maintena, and analysts set peak sales from that drug between $500 million and $1 billion. Johnson & Johnson's ($JNJ) once-monthly antipsychotic, Invega Sustenna, is already bringing in blockbuster sales, and a new, longer-acting formula could give the franchise an even bigger boost. The FDA in January granted J&J priority review for a three-month dosing option of the med, potentially allowing the company to kick off marketing for the drug as early as mid-2015.

- read the FDA safety alert

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