December 13, 2017

Servier and Pfizer's CAR-T candidate licensed from Cellectis shows positive effect in two early-stage leukemia studies.

Preliminary results were presented at ASH in Atlanta.  

Preliminary results from two Phase 1 clinical trials assessing Servier and Pfizer's CAR-T candidate, UCART19, in leukemia patients showed a treatment effect. The first study, CALM, is evaluating UCART19 in adult patients with relapsed/refractory CD-19-positive B-cell acute lymphoblastic leukemia (B-ALL). Five of seven (71%) subjects achieved molecular remission at day 28 after treatment. Molecular remission is defined as negative minimal residual disease (MRD) (the number of residual leukemic cells remaining after treatment). The dose of UCART19 used in the first cohort was about 1/10 of that used in most autologous CAR-T studies. On the safety front, one mild case of acute graft-versus-host disease (GvHD) was observed. No severe neurotoxicity was observed. There was one death due to cytokine release syndrome (CRS) and neutropenic (abnormally low level of neutrophils) sepsis. All other cases of CRS were mild and manageable. The second study, PALL, is assessing UCART19 in pediatric patients with high-risk relapsed/refractory B-ALL. All five children treated achieved MRD negativity enabling them to proceed to allogeneic stem cell transplant. Only one mild case of GvHD was observed. No neurotoxicity occurred and CRSs were mostly mild and all were manageable. Servier and Pfizer are co-developing UCART19. Servier obtained exclusive global rights from Cellectis in November 2015.