Merck Serono is the largest division of Merck. In 2007, total revenues were €4,458 million. In order to achieve comparability with 2006, pro forma figures are used in the following section. They compare the figures for 2007 with those of the former Serono Group and the former Ethicals division combined in 2006. Accordingly, organic growth was 7.4%. This is due largely to higher sales of the targeted cancer therapy Erbitux® and Rebif® for the treatment of relapsing forms of multiple sclerosis (MS). Global sales of Rebif® increased in 2007 to €1,218 million, 5.3% more than the amount reported by the former Serono Group in 2006. A new formulation was launched in September in the EU. Sales of Erbitux® also grew steadily. In 2007, they climbed by 40% to €470 million.

With the acquisition of the former Serono Group, the division’s research and development spending nearly doubled to €879 million.

In a pro forma comparison with 2006, the division increased its gross margin by 10% to €3,765 million. The operating result decreased by 52% to €357 million. Among other things, charges of €531 million for the amortization of intangibles in connection with the Serono purchase price allocation should be taken into account. In addition, Merck Serono incurred expenses of €154 million for ongoing integration measures in 2007. Return on sales (ROS) was 8.0%. Nominal free cash flow amounted to €–6,505 million. This primarily reflects the acquisition of Serono. Free cash flow adjusted for acquisitions and disposals was €774 million.