What a ride Savient Pharmaceuticals (NASDAQ:SVNT) investors have had: from a low of under $3 back in October to over $12 today. And the company's gout treatment, Krystexxa, hasn't even been approved yet.

Back in October, investors became very worried that the safety issues might put the kibosh on the approval of Krystexxa, sending share prices down more than 70% in one day. But Savient pressed on because it had a couple of things going for it. First, until Takeda's Uloric was approved earlier this year, there hadn't been a new drug approved for gout patients in 40 years. Second, Savient is trying to get Krystexxa approved as a secondary treatment for patients who haven't responded to other medications. Combine the unmet need and secondary treatment, and it looks to me like the Food and Drug Administration might overlook the potential safety issue, or at least let the drug through with some label warning.

It's important for investors to remember that side effects are all relative. For instance, Biogen Idec (NASDAQ:BIIB) and Elan (NYSE:ELN) were able to get their multiple sclerosis treatment, Tysabri, back on the market despite the risk of potentially deadly progressive multifocal leukoencephalopathy (PML) because it’s the best treatment available. On the other hand, Roche pulled its psoriasis treatment, Raptiva, from the market because of PML concerns. Not to mention that there are plenty of other drugs to treat psoriasis, such as Wyeth (NYSE:WYE) and Amgen's (NASDAQ:AMGN) Enbrel and Johnson & Johnson's (NYSE:JNJ) Remicade.

The panel of experts that the FDA convened seemed to have understood the relative nature of side effects. Yesterday they voted 14 to 1 to recommend the FDA approve Krystexxa. And the stock price responded, up 27% yesterday and a further 5% so far today.

Of course, the agency doesn't have to follow the panel's recommendation, but the lopsided vote combined with the generally positive tone of the FDA briefing documents released last Friday -- behind a 56% boost to the share price that day -- should give investors confidence that Krystexxa will be approved around its PDUFA date of August 1.

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