1. Merck & Co., Inc., West Point, Pennsylvania 19486, United States
2. Peptides and Small Molecules R&D Department, IRBM Spa, Via Pontina km 30.600, 00071 Pomezia (RM), Italy
3. Merck & Co., Inc., Kenilworth, New Jersey 07033, United States
4. Merck & Co., Inc., Rahway, New Jersey 07065, United States