1. Vaccine Research and Development, Pfizer Ltd., Hurley SL6 6RJ, UK
2. Vaccine Research and Development, Pfizer Inc., Collegeville, PA 19426, USA
3. BioNTech, 55131 Mainz, Germany
4. Department of Biochemistry & Molecular Biology, The University of Texas Medical Branch, Galveston, TX 77555, USA
5. Vaccine Research and Development, Pfizer Inc., Pearl River, NY 10965, USA