Galen has completed the bulk of a complicated rights deal with US generic competitor Barr, three months after US competition authorities began to scrutinise the terms of the transaction.

The two companies have failed to reach final agreement on the most complex aspect of the deal however, with complete settlement of this element unlikely to come for another six weeks.

All parts of the deal had been due to close at the start of February but this was delayed when the competition bureau of the Federal Trade Commission (FTC) asked for more information on their terms.

The three-part transaction first emerged last September as part of a settlement reached by Galen and Barr when Galen agreed to drop two patent lawsuits against the US firm.

The element of the transaction still outstanding relates specifically to the details of this litigation settlement.

The conclusion of two out of the deal's three parts is positive for Galen, however, since it suggests that the FTC is not pursuing its inquiries.

A joint release from Galen and Barr yesterday said that the Craigavon-based firm had closed the sale of its rights to its oral contraceptive, Loestrin, to Barr for $45 million (€37 million).

The two companies have also completed a deal that gives Galen the option to win an exclusive licence for Barr's generic version of another Galen contraceptive, Ovcon.

Galen's senior vice president for finance and planning, Mr David Kelly, said this agreement on its Femhrt hormone replacement therapy and Loestrin contraceptive products was taking longer because it was more complicated.

He said the two firms had been keen to conclude the other parts of the deal in the first quarter.

Galen's shares closed 6p weaker at 843.5p in London last night.