* Raises 2014 adj earnings forecast to $4.75-$4.85/share
* 1st-quarter adj earnings $1.53/share vs est $1.26 (Adds details, analyst comment)
By Natalie Grover
April 24 (Reuters) - Alexion Pharmaceuticals Inc raised its full-year profit forecast for the second time in less than two months after robust sales of its rare-diseases drug Soliris helped it beat average earnings estimate in the first quarter.
Sales of Soliris, Alexion's only drug on the market, rose about 67 percent to $566.6 million, including $87.8 million related to reimbursement of prior-year shipments to France.
Analysts had expected revenue of $560.2 million, according to Thomson Reuters I/B/E/S.
The biotechnology company raised its full-year adjusted earnings forecast to $4.75-$4.85 per share from $4.37-$4.47.
The company cut its selling, general and administrative expense estimate for the full year by $10 million to $550-$570 million, and lowered its estimate for adjusted tax rate by 2 percentage points to 8-9 percent.
The company first raised its profit and sales forecast in March after the French government agreed to raise reimbursement payments for prior shipments of Soliris.
Morningstar analyst Stefan Quenneville said the company was exhibiting a "relatively good operating leverage", considering its focus on rare, "orphan" indications, or conditions that affect less than 200,000 people in the United States.
Soliris, which costs about $440,000 per patient a year, is the only approved treatment for two potentially fatal blood disorders that can damage the kidneys, heart and brain.
It is approved in the United States, the European Union and Japan for the treatment of paroxysmal nocturnal hemoglobinuria and atypical hemolytic uremic syndrome.
Alexion's net income rose to $159.4 million, or 79 cents per share, in the quarter ended March 31, from $82.2 million, or 41 cents per share, a year earlier.
Excluding special items, earnings were $1.53 per share, above analysts' average estimate of $1.26.
Cheshire, Connecticut-based Alexion's shares were up more than 1 percent at $154.82 in morning trading on the Nasdaq on Thursday. (Editing by Maju Samuel and Don Sebastian)