Fertility and CAR T-cells: Current practice and future directions

Chimeric antigen receptor (CAR) T-cells serve to overcome chemotherapeutic resistance and have been proven to be highly effective in B-cell hematologic malignancies. Although initial use has been in patients with multiply relapsed/refractory disease, as CAR T-cells are used earlier in the treatment paradigm, it will be important to explore implications of this novel therapy on cancer late-effects. We sought to assess the current framework for considerations of fertility surrounding CAR T-cell use and identify opportunities for education and future research. To assess current practice patterns regarding post-CAR T-cell fertility, peri-CAR T-cell fertility guidance, utilization of fertility preservation surrounding CAR T-cell administration and identify future areas of research, a cross-sectional survey assessing practice patterns regarding fertility counseling and outcomes surrounding CAR T-cell therapy was distributed electronically to approximately 300 Center for International Blood and Marrow Transplant Research medical centers treating patients with CAR T-cell therapy in the United States and internationally between October 12 and November 2, 2021. One medical provider was asked to complete the study survey on behalf of their institution. We received 96 survey responses, of which 66 centers utilized CAR T-cells and provided at least partial responses that were used for the primary analysis. Centers were varied in demographics, experience in administering CAR T-cells, and aspects of patients receiving CAR T-cells. Eighteen centers exclusively treated pediatric patients, and patients at these centers were more likely to be treated for B-cell acute lymphoblastic leukemia. Seven pregnancies and 5 live births after CAR T-cells were reported from 6 centers (1 pediatric-only). Most centers had no established guidelines in place regarding fertility preservation in the peri-CAR T-cell period or regarding recommendations for avoiding pregnancy/fathering a child after receiving CAR T-cells. Areas for future research were elicited from responding centers and categorized into 3 broad themes, including: standardized peri-CAR T-cell fertility guidelines; long-term fertility outcomes after CAR T-cell therapy; impact of CAR T-cells on a developing fetus; and determining the relevance of studying fertility in patients who receive CAR T-cells. We identified a high degree of variability in peri-CAR T-cell guidance on avoidance of pregnancy/fathering a child, as well as a wide-range of practices surrounding referral for fertility preservation, the latter of which may be likely due to the fact that patients receiving CAR T-cells in the present era are likely multiply relapsed/refractory. In summary, this is the first report of several live-births following CAR T-cells, which highlights the important need for further research in CAR T-cell therapy and fertility, with a host of novel research questions identified.