Clinical Scorecard: Safety, Efficacy and CAR T-Cell Persistence of Obecabtagene Autoleucel (OBE-CEL) in Patients ≥ 55 Years Old with Relapsed or Refractory B-Cell Acute Lymphoblastic Leukaemia (R/R B-ALL)

At a Glance

Key Highlights

• Obe-cel demonstrated a high overall remission rate (87.5%) in patients ≥55 years with R/R B-ALL.
• Low incidence of severe cytokine release syndrome (2.1%) and neurotoxicity (10.4%) was observed.
• Median duration of remission was 21.2 months with durable CAR T-cell persistence.

Guideline-Based Recommendations

Diagnosis

• Confirm diagnosis of R/R B-ALL in adult patients aged ≥55 years.
• Assess Philadelphia chromosome status and prior treatment history including SCT.

Management

• Administer obe-cel using tumour burden-guided dosing following lymphodepletion.
• Infuse obe-cel on Days 1 and 10 targeting a total dose of 4x10^8 CAR T-cells.
• Consider obe-cel as a treatment option for patients ineligible for stem cell transplantation.

Monitoring & Follow-up

• Monitor for cytokine release syndrome and immune effector cell-associated neurotoxicity syndrome, especially within first 3 weeks post-infusion.
• Assess hematological recovery and manage unresolved neutropenia or thrombocytopenia at 3 months.
• Surveillance for severe infections throughout treatment and follow-up.

Risks

• Potential for Grade ≥3 cytokine release syndrome and neurotoxicity, though incidence is low.
• Risk of severe infections in over half of treated patients.
• Treatment-related mortality within 3 months post-infusion approximately 4.2%.

Patient & Prescribing Data

Adults aged ≥55 years with relapsed or refractory B-ALL, including those with prior therapies and SCT.

Obe-cel offers a durable remission with manageable safety profile, suitable for patients with limited treatment options and high-risk disease features.

Clinical Best Practices

• Use tumour burden-guided dosing to minimize toxicity in older patients.
• Early identification and management of CRS and ICANS to reduce severe adverse events.
• Close monitoring of hematologic parameters and infection signs post-infusion.
• Consider patient’s prior treatment history including SCT and Philadelphia chromosome status when planning therapy.

References

• FELIX Trial Clinical Trial Registry
• Roddie et al. NEJM 2024
• European Society for Blood and Marrow Transplantation Annual Meeting 2025