The Food and Drug Administration's laundry list for Arena Pharmaceuticals (Nasdaq: ARNA ) seems to be getting longer. The FDA turned down the development-stage drugmaker's obesity drug lorcaserin last October. In December, Arena said it expected to be able to respond by the end of the year.
Now? Maybe not.
In an announcement highlighting layoffs -- a necessary evil of not having revenue streaming in -- Arena said that the FDA had added a couple of items to its to-do list since the last update.
The FDA had three major issues with lorcaserin. The one questioning the diagnosis of mammary tumors in rats seems easy to clear up. Arena has hired five independent pathologists to give their opinion of whether the tumors are benign or malignant.
Arena believes the rats get mammary tumors because of an increase in prolactin, which isn't relevant to humans. In addition to a three-month study, the "FDA requested that Arena consider performing a separate 12-month study." The FDA can't force a company to do an experiment, as far as I know, but if the agency is asking the Arena to consider it, I'd think doing so might be a good idea.
The third item has to do with proving that brain tumors seen in male rats aren't a concern. This one seems on track, although it remains to be seen whether the data comparing levels in human's spinal fluid will be enough to convince the FDA that the concentration in the brain isn't a problem.
It seems the FDA has added a fourth item to the list, though you wouldn't know it from Arena's press release since it just snuck the item onto the paragraph discussing the third problem. The agency asked Arena to run additional experiments to "characterize lorcaserin's activity at the 5-HT2B receptor to further assess the risk of valvulopathy." The heart valve problem, valvulopathy, was an issue with fenfluramine -- the fen part of Wyeth's fen-phen, which is related to lorcaserin. We can probably thank heart problems with Abbott Labs' (NYSE: ABT ) Merida for the added scrutiny, as well. Assuming Arena has the personnel; these studies can be run at the same time as the others and don't seem to require clinical trials. Depending on exactly what data the FDA wants, this doesn't seem like a limiting step to gaining approval.
Hitting the end-of-the-year goal likely depends on whether Arena will have to do the 12-month study, which would obviously push it into 2012. In a rather confusing press release, the company said in the same paragraph that is believes "that it can resubmit the lorcaserin NDA by the end of 2011" and that "it is possible that certain activities may be required that could impact the timeline for resubmission."
Waiting until 2012 could potentially put the company third in the race for the next obesity drug; Orexigen's (Nasdaq: OREX ) obesity drug Contrave expects to hear back from the FDA next week, and VIVUS's (Nasdaq: VVUS ) Qnexa could pass lorcaserin as well depending on how safety issues of its own play out.
Of course, getting the drug approved is most important. If investors get an inkling that management is trying to cut corners, I'd run.
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