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Oct 23 (Reuters) - Alexion Pharmaceuticals Inc reported a better-than-expected adjusted quarterly profit on strong sales of its blood disorder drug Soliris and raised its full-year profit forecast for the fourth time this year.

Sales of Soliris, Alexion's only drug on the market, rose 39 percent to $555.1 million from a year earlier, beating the average analyst estimate of $541.9 million, according to Thomson Reuters I/B/E/S.

Soliris 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 (aHUS).

The biotechnology company raised its full-year 2014 adjusted earnings forecast to $5.15 to $5.20 per share, from $4.95 to $5.05 per share.

It also raised its revenue forecast to a range of $2.22 billion to $2.23 billion, from its prior view of $2.18 to $2.20 billion.

Analysts expected the company to post a full-year profit of $5.01 per share on revenue of $2.20 billion.

Alexion's net income rose to $177.7 million, or 88 cents per share, in the third quarter ended Sept. 30, from $93.8 million, or 47 cents per share, a year earlier.

Excluding special items, it earned $1.27 per share, beating the average analyst estimate of $1.16 per share, according to Thomson Reuters I/B/E/S.

Alexion shares were up about 3.6 percent at $179.50 in premarket trading on the Nasdaq on Thursday. Up to Thursday's close, the stock had risen more than 30 percent this year.

(Reporting by Shailesh Kuber in Bangalore; Editing by Simon Jennings)