Sep 8, 2026 —
A clinical study published in Cell Stem Cell reports that a base-editing therapy achieved durable clinical remission in patients with sickle cell disease (SCD) and beta-thalassemia from a range of genetic backgrounds. The work, from CorrectSequence Therapeutics and collaborators, evaluated CS-101/CS-206, therapies developed with the company’s transformer Base Editor (tBE).
Base editing enables precise, single-letter changes to DNA without creating double-strand breaks. The study extends earlier results in Chinese transfusion-dependent beta-thalassemia (TDT) patients — five of whom achieved transfusion independence, reported in Nature in 2026 — to four additional patients from Nigeria, Laos, Malaysia, and Pakistan, including one with SCD and three with TDT.
The company reported that all four newly described patients achieved rapid hematopoietic reconstitution and sustained high-level, pan-cellular fetal hemoglobin (HbF) expression, with the three TDT patients becoming transfusion-independent and the SCD patient remaining free from vaso-occlusive crises. CorrectSequence also reported no detectable off-target edits or product-related adverse events in these patients.
The findings support base editing as a broadly applicable approach for beta-hemoglobinopathies across different genetic backgrounds.
