Multicenter Phase II Study of Lenalidomide in Relapsed or Recurrent Adult T-Cell Leukemia/Lymphoma: ATLL-002

Area of Science:

• Hematology
• Oncology
• Clinical Pharmacology

Background:

• Adult T-cell leukemia/lymphoma (ATL) has a poor prognosis with limited treatment options.
• Lenalidomide has shown preliminary antitumor activity in relapsed ATL.

Purpose of the Study:

• To evaluate the efficacy and safety of lenalidomide monotherapy in patients with relapsed or recurrent ATL.

Main Methods:

• A phase II study enrolled patients aged 20+ with relapsed/recurrent ATL subtypes (acute, lymphoma, unfavorable chronic) previously treated with chemotherapy.
• Patients received oral lenalidomide 25 mg/d continuously until disease progression or toxicity.
• Primary endpoint was overall response rate; secondary endpoints included safety, tumor control, and survival metrics.

Main Results:

• 11 of 26 patients (42%) achieved an objective response, including 4 complete responses.
• Tumor control rate was 73%, with a median progression-free survival of 3.8 months and overall survival of 20.3 months.
• Common Grade ≥3 adverse events included neutropenia (65%), leukopenia (38%), lymphopenia (38%), and thrombocytopenia (23%), which were manageable.

Conclusions:

• Lenalidomide demonstrated clinically meaningful antitumor activity and an acceptable safety profile in relapsed/recurrent aggressive ATL.
• Lenalidomide shows potential as a new treatment option for aggressive ATL.
• Further investigation of lenalidomide in ATL and other mature T-cell neoplasms is warranted.