Acknowledgments
We thank Timm Fiebig (Institute of Clinical Biochemistry, Hannover Medical School, Hannover, Germany) and Mario Schubert (Department of Biosciences, University of Salzburg, Billrothstr. 11, 5020, Salzburg, Austria–Christian Doppler Laboratory for Innovative Tools for Biosimilar Characterization, University of Salzburg, Hellbrunnerstrasse 34, 5020, Salzburg, Austria) for the insights on the NMR spectra assignment and useful discussion.
We thank all the colleagues of Analytical Department–Technical R&D–GSK Vaccines S.r.l. (Siena, Italy) for useful discussion and the critical reading of the manuscript.