TG Therapeutics announces publication of data from Phase I/Ib trial of U2
TG Therapeutics announced the publication of results from the multicenter first-in-human Phase I/Ib combination trial of ublituximab, the Company's anti-CD20 monoclonal antibody, and umbralisib, the Company's oral once-daily PI3K delta inhibitor in Blood, the Journal of the American Society of Hematology. The paper includes safety and efficacy information from patients with chronic lymphocytic leukemia and non-Hodgkin Lymphoma, including 22 patients with CLL or small lymphocytic lymphoma and 53 patients with NHL treated with the combination of ublituximab and umbralisib, referred to as "U2". Dose-escalation was performed with a 3+3 design evaluating fixed doses of ublituximab and escalating doses of umbralisib to establish the maximum tolerated dose. Safety data was available from all 75 patients and demonstrated that the U2 combination was well tolerated with the majority of adverse events being grade 1 or 2 in severity and no maximum tolerated dose achieved in either CLL or NHL. Importantly, U2 exhibited low rates of immune-mediated toxicities typically associated with other PI3K-delta inhibitors including colitis, pneumonia/pneumonitis, or hepatic toxicity, and discontinuations due to AEs were limited. Efficacy data was available from 69 patients and showed the combination to be highly active with a 72.5% clinical benefit rate across all subtypes of B-cell cancers enrolled in the study. Of note, a median PFS of 27.57 months was observed in patients with relapsed/refractory CLL treated at therapeutic dose levels of umbralisib and a 65% overall response rate was observed in patients relapsed/refractory indolent NHL, including a 100% ORR amongst MZL patients.