Whenever transparent containers are used in a clinical trial and there are visible differences between the verum and the placebo the trial drugs have to be blinded because the trial participants must not be able to detect what they are taking or what is being dispensed to them under any circumstances. If the trial is conducted on an international scale, the product descriptions have to be available in diverse languages. For its international Phase III study of an immunoglobulin, CSL Behring required both: a solution for blinding the vials and a label providing ample space for product information in several languages. An additional requirement: the flip-off cap of the vial has to be easy to open and must not impair the blinding.

The CTS experts from Schreiner MediPharm found the ideal solution in a combination of Flexi-Cap and a Booklet-Label. For blinding the vials, two opaque-printed, silver-colored film caps are used. One of the caps wraps around the closure and upper part of the container without covering the flip-off cap. The second cap covers the lower part and bottom of the container. A Booklet-Label retains both caps on the container—while offering a comprehensive, multi-lingual product description of many pages. The construction of the caps plus Booklet-Label is manually affixed using special application aids and can be flexibly adapted to diverse vial sizes and shapes.

Compared to other label solutions, which are complex to apply and can be easily peeled off, this combination of Flexi-Cap and a Booklet-Label has special advantages. It offers fast and reliable blinding combined with clear and efficient marking of the vials.

^{* Medicine containing active ingredients
** Dummy drug containing no medicinal substances}