This study is a part of the IG TATRY study funded by Takeda Pharma Sp. z o.o. M Mach-Tomalska received lecture fees and/or travel grants from CSL Behring, Octapharma and Takeda. AP Pukas-Bochenek received lecture fees and/or travel grants from Takeda. M Malanowska received lecture fees and/or travel grants from CSL Behring, Octapharma and Takeda. M Pac received lecture fees and/or travel grants from Biogen, CSL Behring, Grifols, Octapharma, Pfizer and Takeda. S Drygała was an employee of Takeda Pharma Sp. z o.o.at the time of the study and is currently employed by AstraZeneca. M Kamieniak is an employee and shareholder of Takeda Development Center Americas, Inc. J Kasprzak is a permanent employee of Takeda Pharma Sp. z o.o. E Heropolitańska-Pliszka received lecture fees and/or travel grants from CSL Behring, Kedrion, Octapharma and Takeda. The authors have no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript apart from those disclosed.