Randomisation
Subjects will be randomised on day -1 or 0 to either treatment arm after confirmation that the subject is eligible for the study. There will be a block randomisation. Every site will initially receive an even number of with a MedCode (e.g. 1000-1) consecutively numbered blisterpacks, half of them containing verum, the other half containing placebo. The block size ranges from 2 (alternating verum and placebo) to 6 (up to 3 times placebo/verum in a row). The number of blocks and the block size are unknown to the sites. Blisterpacks have to be used in ascending order, i.e. the first patient to be randomised receives the blisterpack with the lowest number. Immediately after randomisation (not later than 2 h), the clinical trial center of the Sponsor has to be informed about randomisation by fax.