This 2015 Phase Ib/IIa single-group dose escalation study (Journal of Urology, PMID: 25910967) investigated the safety, tolerability, and preliminary efficacy of intravesical mistletoe (Viscum album) extract in 36 patients with nonmuscle invasive bladder cancer (NMIBC). Following tumor resection, patients received weekly intravesical instillations of mistletoe extract for six weeks. At
