(Updated with company comment, new analyst comments, stock reaction)
LEXINGTON, Mass. (
shares tumbled Thursday after an analyst downgraded the stock on concerns that kidney disease patients treated with the company's intravenous iron replacement therapy Feraheme are ending up in the hospital with severe allergic reactions.
"We are aware of several patients hospitalized with anaphylactiod reactions to Feraheme. We are aware of one death that may or may not be directly related to Feraheme," wrote SummerStreet Research Partners analyst Carol Werther in a note to clients Thursday. She downgraded AMAG to neutral from buy and cut her Feraheme sales forecasts.
AMAG shares are down $5.12, or 11%, to $40.13 in recent Thursday trading. The stock has traded as low as $37.70.
Werther says she doesn't know how many patients have been treated with Feraheme since the drug launched in July, so it's not possible to say whether the rate of severe allergic reactions being observed in the real world is greater than what was seen in Feraheme's clinical trials.
In clinical trials, hypersensitivity reactions to Feraheme were reported in 0.2%, or 3 patients out of 1.726 patients treated, according to the drug's label approved by the U.S. Food and Drug Administration.
Feraheme is an intravenous form of iron used to treat anemia in patients with chronic kidney disease.
AMAG officials, however, deny that Feraheme is causing any more safety problems than expected.
AMAG's Chief Business Officer David Arkowitz said, "The Feraheme safety profile we're seeing since commercial launch has been consistent with the drug's label." He added that, "No deaths have been attributed to Feraheme in clinical trials or in the drug's commercial experience."
More than 20,000 patients have been treated with Feraheme to date, said Arkowitz.
Other analysts are defending AMAG after speaking with company officials. J.P. Morgan analyst Matt Roden, in a note to clients, wrote, "In our view, the key points on Feraheme safety are 1) the safety profile in the commercial setting has been as good or better than is reflected in the label; 2) all IV irons cause anaphylactoid reactions with some frequency; 3) there have been no treatment-related deaths with Feraheme."Roden reiterated his buy rating on AMAG, adding, "We believe the reports of safety events are in line with physician expectations, and see little if any impact to commercial uptake. Accordingly, we see current weakness as a buying opportunity."
-- Reported by Adam Feuerstein in Boston
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