Elan Corp says that second-quarter net profit shot up to $2.29 billion compared with a loss of $28.5 million, thanks to $2.5 billion income banked from the transfer to Biogen Idec of its multiple sclerosis blockbuster Tysabri.

Earlier this year, the Irish drugmaker sold its stake in Tysabri (natalizumab) to Biogen in return for $3.25 billion, plus royalties, and Elan says that revenues from continuing operations reached $56.3 million which included a 50% share of Tysabri profits for the month of April and a royalty of 12% of global net sales of the MS drug for May and June.

Elan ended the quarter with over $1.90 billion in cash and equivalents and it has no debts.

The last few months for Elan have been dominated by Royalty Pharma's attempts to acquire the company but last month it finally abandoned its $8 billion bid. Recently, shareholders in the Dublin-headquartered group approved a share buyback plan, but voted against a royalties alliance with Theravance, the acquisition of Austria's AOP Orphan Pharmaceuticals and a plan to spin-off its early-stage Alzheimer’s drug ELND005.

Elan has since been looking for buyers and chief executive Kelly Martin said "we are focused squarely on the process of exploring a sale of the company". He added that the board of directors "are in complete alignment with regard to exploring all opportunities to maximise shareholder value".