Funding for this research was provided by:
Received: 28 July 2020
Accepted: 9 June 2021
First Online: 29 June 2021
: The ethics committee of Ulm University approved the COUP-1 trial as leading ethics committee for all German sites. In addition, the leading Austrian ethics committee also approved the study. All patients signed informed consent according to GCP.The trial is registered at ExternalRef removed (NCT03474744) and the European Clinical Trials Database (2017 EudraCT: 2017–003150-16). Protocol version: 4.0. (May 5th 2020).
: Not applicable.
: Copanlisib and Rituximab are provided by Bayer AG and Celltrion Healthcare. The authors declare no conflicts of interest. The study was not externally reviewed. The authors have no financial relationship with Bayer AG or Celltrion Healthcare.