When reviewing nearly 3 decades of publications on adoptive T-cell transfer, the reviewers found a total of 74% of immunocompromised patients had responded to this technique. In particular, 62%, 74%, and 85% of patients responded to EBV-, AdV-, and CMV-specific T-cell transfer, respectively. In addition, treatment success has been reported using doses as small as a few hundred cells, though the use of higher doses has been reported in studies employing more complex in vitro culturing techniques.
Other Strategies for Immunosuppression After HSCT
Pamela S Becker, MD, PhD, of the division of hematology at the University of Washington in Seattle, told Hematology Advisor, “Antimicrobial prophylaxis and frequent monitoring for infection are the 2 best strategies to improve immunosuppression in adult patients undergoing allogeneic HSCT.”
Parameswaran Hari, MD, MS, of the division of hematology and oncology at the Medical College of Wisconsin in Milwaukee, told Hematology Advisor, “In my opinion, the best strategy [to improve immunosuppression] is post-transplant cyclophosphamide, but this has not yet been studied in a randomized large study [that compares it with] other existing modalities.”
Possible Limitations and Future Directions
Novel development techniques have removed many of the manufacturing-related barriers to the advancement of virus-specific T-cell products. However, several logistical, regulatory, and time-related barriers still exist that must be addressed before widespread clinical application of this technique can become feasible. Safety and efficacy of adoptive T-cell transfer has not yet been established in placebo-controlled studies.
“Multinational efforts are required to clarify the status of cellular treatment in first-line clinical routine, with the overall objective of strengthening evidence-based treatment guidelines for refractory viral infections post-HSCT,” the reviewers concluded.
1. Kaeuferle T, Krauss R, Blaeschke F, et al. Strategies of adoptive T-cell transfer to treat refractory viral infections post allogeneic stem cell transplantation [published online February 6, 2019]. J Hematol Oncol. doi:10.1186/s13045-019-0701-1