NEW YORK, NY (

TheStreet

) Citibank biotech analyst Yaron Werber downgraded

AMAG Pharmaceuticals

(AMAG) - Get Report

to hold from buy Wednesday night, warning of a slow launch for the company's iron replacement therapy Feraheme.

"Based on our checks, we expect Feraheme's launch to be slow and Street estimates need to come down. In dialysis, there is a lukewarm reception and not expecting a big uptake until 2010. We are bullish about pre-dialysis, but opportunity is small currently and will take time to build the market," writes Werber.

The analyst significantly reduced his Feraheme sales forecast across the board. His 2009 Feraheme sales estimate was lowered to $13 million from $19 million; his 2013 estimates falls to $299 million from $357 million.

"Impediments to using Feraheme are (1) high price ahead of dialysis bundling in 2011, (2) lack of key differentiation, and (3) reimbursement concerns. Thus, we are lowering estimates in dialysis," writes Werber.

Of course, Werber's earnings estimates were reduced as well, so too was his price target on AMAG, cut to $52 from $65 a share.

AMAG shares hit $56 the day after Feraheme received FDA approval, but since then, the stock has slipped as much as 25% to a low of $41 at the end of August on concerns over the drug's launch.

Werber echoes these Feraheme launch worries but he's certainly not a leading indicator. In fact, you could argue AMAG's share price may have found a bottom now that a major analyst has weighed in with a downgrade and cut his Feraheme estimates.

AMAG shares closed Wednesday at $43.70.

-- Reported by Adam Feuerstein in Boston

Adam Feuerstein writes regularly for TheStreet.com. In keeping with TSC's editorial policy, he doesn't own or short individual stocks, although he owns stock in TheStreet.com. He also doesn't invest in hedge funds or other private investment partnerships. Feuerstein appreciates your feedback;

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