Generation of Clinical Grade Adenovirus Specific T Cells for Adoptive Immunotherapy After Allogeneic Stem Cell Transplantation : Clinical Trial

Allogeneic Hematopoietic Stem Cell Transplantation (HSCT) has improved over the last decades. However, after HSCT and especially with matched unrelated, cord blood or haploidentical donors, patients often experience a deep immunodeficiency, increasing susceptibility to viral infections. Among them, adenovirus (ADV) systemic infection, often refractory to antiviral treatment, is associated with a high mortality rate up to 50% (even more in children). Viremia monitoring after HSCT has contributed to improve survival allowing the implementation of a pre-emptive anti-viral treatment before any appearance of clinical signs of ADV disease. Nevertheless, no anti-viral drug is authorized for ADV infections, although intravenous (IV) cidofovir seemed to be, up to now, the most efficient. However, nephrotoxicity, especially tubular dysfunction, is often described, requiring hydratation and uroprotection with probenecid and limiting the treatment period.

Meanwhile, adoptive transfer of ADV-specific T cells, prepared with an immunomagnetic clinical grade technology, is becoming an alternative treatment that has already proved feasible, safe and helpful in viral clearance and immune reconstitution related to an in vivo expansion of ADV-specific T cells leading to clinical improvement (Feuchtinger et al, 2006, 2015; Qazim et al, 2013). Our team proposes a multicenter Phase I/II clinical trial with ADV-specific T cells where 14 patients, with refractory ADV infection or disease after unrelated Peripheral blood or umbilical cord blood HSCT, are included.