1. Centre for Human Drug Research, Leiden, The Netherlands
2. EMD Serono, Rockland, MA, USA
3. VU Medical CenterAmsterdam, The Netherlands
4. Janssen Pharmaceutical Companies of Johnson & JohnsonSpring House, PA, USA
5. Merck Research LaboratoriesRahway, NJ, USA
6. Merck Research LaboratoriesBrussels, Belgium
7. HAL Allergy B.V.Leiden, The Netherlands
8. Skane University Hospital, Department of Respiratory Medicine and Allergology, Institute for Clinical Science, Skane University, Lund, Sweden
9. Departments of Clinical Pharmacy & Pharmacology and General PracticeUniversity Medical Center Groningen, Groningen, The Netherlands
10. QPS NetherlandsGroningen, The Netherlands