UPDATE 1-Pharming says new test results Rhucin positive

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AMSTERDAM, June 16 (Reuters) - Dutch biotechnology firm Pharming (PHAR.AS) said on Monday safety and efficacy results from a north American trial with its key drug Rhucin were positive, igniting 53 percent rally in its shares.

Pharming said the North American results were in line with positive results from a European randomized placebo-controlled Phase III clinical trial reported previously.

Pharming shares were up 53.4 percent at 1.12 euros, their highest level in more than three months, by 1519 GMT.

Rhucin treats hereditary angioedema (HAE), a disorder characterised by acute attacks of painful swelling of the skin, intestine, mouth and throat.

In March the European Medicines Agency (EMEA) denied approval for the drug as it doubted the drug's clinical benefits because of potential immune system reactions, but Pharming said it would file a new request with additional data from North American tests.

Pharming said it intends to file regulatory submissions for Rhucin in several early launch markets in the second half of 2008 and it would meet the EMEA and the U.S. Food and Drug Administration (FDA) to accelerate regulatory filings in Europe and in the United States.

Rhucin is derived from the milk of transgenic rabbits and the company has said the drug could generate annual sales of up to 600 million euros ($921.6 million) in the United States and Europe combined.

One in every 30,000 people suffers from HAE, Pharming has said. Patients have an average of seven attacks per year.

Rhucin would be the second medicine from a genetically engineered animal to get to market and analysts see the drug as key to profitability of the group, which made a net loss of 35.6 million euros in 2007.

GTC Biotherapeutics Inc.'s (GTCB.O) goat-derived drug ATryn, for a rare blood clotting disorder, was the first drug from a transgenic animal to win approval in 2006. (Reporting by Harro ten Wolde; editing by Sue Thomas)