Shanghai – September 12, 2026 -- CorrectSequence Therapeutics (Correctseq) reported that its transformer Base Editor (tBE) platform achieved sustained transfusion independence or elimination of vaso-occlusive crises (VOCs) in four new patients from Nigeria, Laos, Malaysia and Pakistan, extending clinical validation beyond the Chinese cohort where five patients previously achieved full transfusion independence.
Study published in Cell Stem Cell confirms cross-genetic efficacy of CS-101/CS-206
The peer-reviewed paper, published online September 7, 2026, details results from one sickle cell disease (SCD) patient and three transfusion-dependent β-thalassemia (TDT) patients treated with CS-101/CS-206. All four achieved rapid hematopoietic reconstitution, sustained high-level pancellular fetal hemoglobin (HbF) expression, and no detectable off-target edits or product-related adverse events.
21-year-old Nigerian SCD patient sees hemoglobin rise from 7.7 to 12.9 g/dL
The patient, who suffered more than four VOCs in the year prior to enrollment, achieved neutrophil engraftment at 13 days and platelet engraftment at 21 days post-infusion. Her HbF level rose from 3.5% to 62.2%, while HbS dropped from 76.1% to 31.6%. Over 15.5 months of follow-up, she recorded zero VOCs.
Three TDT patients across Asia reach transfusion independence within 17.5 months
Patients aged 3 to 29 from Laos, Malaysia and Pakistan achieved neutrophil engraftment at 13 days and platelet engraftment at 27 days. Mean total hemoglobin reached 11.6±1.2 g/dL, with mean HbF rising to 9.8 g/dL by month three. All three sustained transfusion independence through a mean 17.5-month follow-up, with no selection errors or related adverse events.
tBE outperforms nuclease-based editing on engraftment speed and HbF levels
In SCD trials, tBE achieved neutrophil engraftment in 13 days versus 27 days for Cas9 and 23 days for Cas12a, and platelet engraftment in 21 days versus 35 and 25 days respectively. tBE sustained HbF above 60% of total hemoglobin, compared with under 50% for Cas9 and Cas12a regimens. The platform avoids DNA double-strand breaks, reducing risks of p53 activation, large deletions and chromosomal rearrangements associated with nuclease-based approaches.
Over 30 patients treated globally with 100% response rate reported to date
CS-101 and CS-206 have now treated more than 30 patients across China, Africa, Southeast Asia and South Asia, with all achieving transfusion independence or VOC elimination. CS-101, the first base-editing candidate to enter global clinical development with its first patient treated in October 2023, has completed Phase I and is now in pivotal trials. Phase I patients have maintained transfusion independence for over a year, with the longest duration approaching three years.
Correctseq expands pipeline to metabolic and cardiovascular disease targets
Correctseq CEO Mou Xiaodun said the company is extending tBE into familial chylomicronemia syndrome, ASCVD/hyperlipoproteinemia, homozygous familial hypercholesterolemia and metabolic dysfunction-associated steatohepatitis, with multiple programs advancing toward global IND filings. Founder Chen Jia, who also directs the Gene Editing Center at ShanghaiTech University, noted the team is separately exploring RNA editing, prime editing and mitochondrial DNA editing for additional therapeutic areas.