The USA’s Gen-Probe has launched an offer for Innogenetics which tops an earlier bid made by fellow Belgian firm Solvay.

The cash offer from Gen-Probe is worth approximately 215 million euros and Innogenetic stockholders would receive 188 million euros. This equates to 6.10 euros per share, a 7% premium to Innogenetics' closing price on June 2 and 6% higher than Solvay’s 5.75 euros per share offer made as part of its friendly takeover bid made in April.

Gen-Probe is interested in Innogenetics because it says that a combined entity would create “the largest stand–alone molecular diagnostics company in the world”, with pro forma 2008 sales in excess of $500 million. It would offer “a broad range of nucleic acid and immunoassay tests to identify bacterial and viral infectious diseases, genetic and neurological disorders, transplant compatibility, and cancer”, the US firm added.

Gen-Probe chief executive Hank Nordhoff also noted that a deal would clearly help his firm grow in the European molecular diagnostics arena, “which we estimate is growing at roughly double the rate of the US market". It would also provide access to “a number of complementary products, technologies and markers that are generating revenue today or that we believe could be commercialised in the future”.

Mr Nordhoff concluded by saying that the offer represents “full and fair value for all Innogenetics shareholders”. The offer is equivalent to around four times the revenues generated by Innogenetics’ diagnostics subsidiary; the Ghent-based firm recently announced a restructuring which includes the closure of its therapeutics subsidiary GENimmune.

The move by Gen-Probe has come as a surprise and Innogenetics, which saw its shares rise 12.3% to 6.41 euros, said its board will consider the offer before making any comment. As for Solvay, it is evaluating its options now that its own proposed acquisition, which looked fairly clear-cut, has been thrown into doubt.

The announcement of a potential tie-up between Solvay and Innogenetics on April 25 seemed a natural extension to the firms’ R&D co-operation signed in 1997. Solvay already has a stake of just under 7% in the biotechnology group and chief executive Werner Cautreels said then that “the time has now come to take our long-standing relationship to a new level”.