Long-Term Follow-Up of Patients Receiving Stem Cell-Based Regenerative Therapies
DOI:
https://doi.org/10.5281/zenodo.22274944Keywords:
Long-term follow-up; Gene therapy; Regenerative medicine; Insertional oncogenesis; PharmacovigilanceAbstract
Background: Stem cell-based regenerative therapies are given once and persist, so their adverse events fall outside the window in
which conventional pharmacovigilance operates.
Objective: To set the follow-up durations mandated in each jurisdiction beside the events actually observed in published
long-term cohorts.
Methods: Narrative review of regulatory documents, gene therapy cohorts and long-term clinical follow-up studies.
Findings: United States guidance recommends fifteen years for integrating vectors and the European Union requires at least five
years then yearly follow-up. Seven haematologic cancers occurred among 67 patients given elivaldogene autotemcel, with onset
from fourteen to ninety-two months, and 38 suspected secondary T-cell malignancies were reported against approximately 42,500
exposures. No teratoma was seen in 41 recipients of pluripotent-derived grafts.
Conclusions: The evidence supports the mandated durations as proportionate to observed event timing; it does not show what
fraction of patients remain in follow-up, since attrition inside these protocols is unpublished.
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