Swiss drug giant Roche Holding on Wednesday made a hostile $5.7bn bid for DNA diagnostics company Illumina. Roche had previously attempted “multiple efforts” to start negotiations but Illumina refused to enter into “substantive discussion,” the company said.

The offering of $44.50 a share represents an 18 percent premium over Illumina’s closing price per share on Tuesday.

Roche said an acquisition of Illumina would provide benefits such as increased strength in the life sciences and diagnostics sector.