Dr Diego Leon-Rico, representing SCIDNET Partner GOSH (Great Ormond Street Hospital), presented a poster in the annual European Society of Gene & Cell Therapy Congress (Barcelona, 22-25 October 2019). Below, follows a summary of the poster.
Manufacture of an ATMP for the treatment of X-linked Severe Combined Immunodeficiency (X-SCID)
D Leon-Rico, J W Schott, E Armenteros-Monterroso, K F Buckland, A Diasakou, I Pereira C B Ferreira, A Cavazza, K L Shaw, M Armant, D B Kohn, S Y Pai, A J Thasher, C Booth
1: UCL GOS Institute of Child Health, 2: Great Ormond Street Hospital for Children NHS Foundation Trust, 3: U.C.L.A., 4: Boston Children’s Hospital, 5: Hannover Medical School
X-SCID is a primary immunodeficiency characterised by the absence of T, B and NK cells. Patients with X1-SCID suffer from recurrent and life-threatening infections. Currently, the only curative treatment is haematopoietic stem cell transplant (HSCT). Previous ex-vivo gene therapy clinical trials have been conducted for this disease, using both gamma retroviral vectors (g-RV) and self-inactivating (SIN) g-RV. However, numerous clinical trials for many diseases, including X-SCID have moved to the use of SIN-lentiviral vectors (LVs). Great Ormond Street Hospital is one of the sites for this clinical trial. Here we describe the optimised 3-day manufacturing procedure consisting of several steps: CD34+ selection using COBE and CliniMACS®Plus from the starting material (mobilised peripheral blood stem cells or bone marrow), pre-stimulation culture in the presence of SCF, FLT3L and TPO cytokines, transduction with a SIN LV where the expression of the therapeutic transgene is driven by the EFS promoter, and a final harvest / formulation process where the transduced cells are resuspended in a commercially available freezing mix and transferred to cryobags. Finally, the cells are cryopreserved using a control rate freezer and stored at LN2 vapour phase. Required QC tests are performed both pre-freeze and post-thaw. The introduction of transduction enhancers (LentiBOOST™ and Protamine sulphate) allows the use of 4-times less vector whilst still achieving enhanced transduction efficiency. A stability study using healthy donor cells has been also conducted demonstrating that the cryopreserved transduced cells are stable for at least 6 months in LN2 vapour phase.
This is the link to the meeting website: