Autolus Therapeutics Presents Long-Term Follow-Up from FELIX Study Demonstrating Obe-Cel's Potential for Long-Term Remission in R/R B-ALL at EHA Congress

Autolus Therapeutics presented long-term follow-up data from the FELIX study of obe-cel in relapsed/refractory B-cell acute lymphoblastic leukemia (B-ALL) at the European Hematology Association Congress. The median duration of response increased to 42.6 months, with more than half of patients still in remission at 24 months. The results suggest that a proportion of patients with r/r B-ALL may not need further therapy following treatment with obe-cel.

Autolus Therapeutics plc (Nasdaq: AUTL) has announced updated long-term data from its FELIX study of obe-cel, a next-generation programmed T cell therapy, at the European Hematology Association (EHA) Congress. The study, which focused on adult patients with relapsed/refractory (r/r) B-cell acute lymphoblastic leukemia (B-ALL), provided encouraging results regarding the durability of response and potential for long-term remission.

The median duration of response in the FELIX study has increased to 42.6 months after an additional 11 months of follow-up, indicating a significant improvement in the treatment's effectiveness. More than half of the patients remained in remission at 24 months, with 38% of ongoing responders not requiring any subsequent therapy by month 33. These findings suggest that a proportion of patients with r/r B-ALL may not need further therapy following treatment with obe-cel.

Dr. Christian Itin, CEO of Autolus Therapeutics, commented on the results, stating, "Obe-cel’s durability of response without any subsequent therapy in two out of every five responders is a key factor leading the transformation of therapy for adult r/r B-ALL patients. At a median follow-up of 33 months, we are encouraged to see a continuation of the long-term plateau we observed at the last data cut."

The study also presented data stratified by age, demonstrating that obe-cel treatment was associated with deep and durable remissions, favorable overall remission rates, event-free survival, and overall survival, with a low incidence of Grade ≥3 CRS and ICANS in both age groups (55 years and ≥55 years). This indicates that obe-cel is effective and has a positive benefit-risk profile regardless of patient age.

Additionally, the study explored the use of CAR T-cell therapy as a definitive treatment for adult r/r B-ALL without transplant. The results suggest that obe-cel may be a definitive treatment for some patients, with specific analysis needed to determine which patients may benefit from additional treatments.

The FELIX study enrolled over 100 patients across 30 leading academic and non-academic centers in the United States, United Kingdom, and Europe. The trial's primary endpoint was overall response rate, with secondary endpoints including duration of response, MRD negative complete remission rate, and safety.

References:
[1] https://www.marketscreener.com/quote/stock/AUTOLUS-THERAPEUTICS-PLC-44336207/news/Autolus-Therapeutics-Presents-Long-Term-Follow-Up-from-the-FELIX-Study-Demonstrating-Obe-Cel-s-Poten-50220231/
[2] https://www.streetinsider.com/Globe+Newswire/Autolus+Therapeutics+Presents+Long-Term+Follow+Up+from+the+FELIX+Study+Demonstrating+Obe-Cels+Potential+for+Long-Term+Remission+in+RR+B-ALL+at+the+2025+European+Hematology+Association+%28EHA%29+Con/24927415.html