LEXINGTON, Mass. ( TheStreet) -- AMAG Pharmaceuticals ( AMAG) struck a cautious but optimistic tone Wednesday night about the nascent commercial launch of its intravenous iron replacement therapy Feraheme.

Meantime, AMAG CEO Brian Pereira quickly shot down concerns about the looming entry of a low-priced generic competitor during the question-and-answer portion of the company's second-quarter conference call.

AMAG began selling Feraheme on July 13, so the company did not report any sales Wednesday night. The drug, given in two, 17-second injections about a week apart, is used by doctors to correct anemia in patients with chronic kidney disease.

"I am pleased to announce that AMAG received reports of patients being treated with Feraheme within days of commercial availability," said AMAG's commercial operations chief, Tim Healey.

Kidney dialysis chains, where kidney dialysis patients are treated, are beginning pilot programs with Feraheme that often lead to full adoption of the drug, added Healey. The company is also marketing Feraheme to doctors who treat pre-dialysis kidney disease patients.

Given the early launch, however, AMAG declined to offer any specifics about the adoption of Feraheme at the major U.S. dialysis providers, notably Davita ( DVA) and Fresenius ( FMA), nor did the company provide 2009 Feraheme sales guidance.

Wednesday's second-quarter report from AMAG was somewhat co-opted by a surprise announcement Tuesday that Watson Pharmaceuticals ( WPI) had licensed a generic version of the currently marketed iron replacement therapy Ferrlecit from a privately held drugmaker.

The U.S. Food and Drug Administration is reviewing the generic version of Ferrlecit, and Watson said it would immediately launch the drug if and when it was approved. Watson sells branded Ferrlecit today under a contract from Sanofi-Aventis ( SNY) but that arrangement is set to expire at the end of the year.

Competition from a lower-cost iron could conceivably gum up AMAG's Feraheme launch plans, but AMAG CEO Pereira said the FDA has been extremely hesitant about approving any generic intravenous iron without significant clinical and safety data to prove that such copycats are equivalent to the branded versions.

"There are significant clinical regulatory and commercial hurdles for the entry of any generic iron," said Pereira.

"First, bioequivalence will have to be demonstrated, and we have not seen any evidence of such studies for the proposed generic that Watson has licensed in. Second, is clinical trials demonstrating safety and efficacy equivalents will be essential to drive any clinical update by physicians."

Ironically, Watson has a pending citizen's petition filed with FDA seeking to block the approval of generic intravenous irons. On its conference call Tuesday, Watson executives didn't comment on how that lobbying effort jibes with the company's new effort to sell a generic if approved.

For the second quarter, AMAG reported a net loss of 26.55 million, or $1.55 a share, in line with the Street consensus estimate.

AMAG shares closed Wednesday at $49.90.

-- 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; click here to send him an email.