Shares in Pharming have shot up over 27% after the Dutch biotechnology firm said that results from a study of its lead product Rhucin, for the treatment of acute attacks of hereditary angioedema, are so impressive that the trial can be stopped.

The Leiden-headquartered group has completed an interim analysis of its European randomised placebo-controlled double-blind clinical study designed to evaluate efficacy and safety of Rhucin (recombinant human C1 esterase inhibitor) in the treatment of acute attacks of hereditary angieoedema. None of the patients receiving Rhucin showed a relapse of their attack, nor any treatment-related adverse events during this study, confirming its safety profile.

Details of the data will be presented on August 30 at a meeting in London, Pharming said, but added that after consulting with the independent data monitoring committee it has decided to discontinue further randomised treatments within the clinical study “for methodological and ethical reasons”. Rhucin is a human protein developed through Pharming's proprietary technology in the milk of transgenic rabbits.

Pharming noted that it has included the analysis in its marketing dossier submitted to the European Medicines Agency last July and data were also submitted to the Food and Drug Administration in the USA where an independent placebo-controlled randomised clinical study assessing the safety and efficacy of Rhucin is expected to be completed in the next few months.

Bruno Giannetti, chief operations officer at Pharming, said that the product has “an excellent safety profile based on the results of various studies in which, in total, well over 100 infusions were given to subjects” and “importantly, no relapses of any of the attacks occurred”.

The news is hugely positive for Pharming and it is now very optimistic about getting approval in Europe with a possible launch early next year. Currently, there are no drugs approved to treat hereditary angioedema, a genetic disorder that affects roughly one in 30,000 people in the western world. Sufferers have an average of seven acute attacks per year, characterised by painful swelling of soft tissues, which can be life-threatening if the throat is involved.

The progress being made by Rhucin suggests that Pharming can expect some offers for partnering the treatment in the very near future and analysts have estimated that total market sales for treating the illness could amount to 500-600 million euros.

Competition from Jerini's icatibant

In terms of competition in the hereditary angioedema field, only last week German firm Jerini announced the acceptance of its marketing application by the EMEA for icatibant. The agency’s Committee for Medicinal Products for Human Use has also granted Jerini accelerated assessment status for the review of its submission, and could give an opinion as early as the first quarter of 2008. By Kevin Grogan