Lenalidomide monotherapy demonstrated “meaningful” antitumor activity in patients with relapsed or recurrent aggressive adult T-cell leukemia/lymphoma (ATL), according to new findings.
Among 26 patients enrolled in the study, 11 responses were observed, for an overall response rate of 42% (95% CI, 23%-63%). This included four complete responses and one unconfirmed complete response.
The tumor control rate was 73%, achieved in 19 patients, and the toxicity profile was manageable. Overall, these findings hint at the potential of lenalidomide to “become a treatment option in this patient population,” wrote Takashi Ishida, MD, of Nagoya City University Graduate School of Medical Sciences, Aichi, Japan, and his colleagues (J Clin Oncol. 2016 Sep 12. doi: 10.1200/JCO.2016.67.7732).
ATL is a difficult disease to treat, and it has a poor prognosis, as it is resistant to conventional chemotherapeutic agents and treatment options are currently limited. Lenalidomide, an oral immunomodulatory agent, has demonstrated both antiproliferative and antineoplastic activity in B-cell lymphomas in preclinical studies, and a previous phase I trial established a maximum tolerated dosage (25 mg/d) in a small cohort of Japanese patients with relapsed ATL or other peripheral T-cell lymphomas (PTCL).
Based on these preliminary results, Dr. Ishida and his coauthors designed the current multicenter phase II study, to evaluate the efficacy and safety of lenalidomide monotherapy in 26 patients with relapsed or recurrent ATL.
At a median follow-up of 3.9 months, responses were observed in 33% of patients (5 of 15) with acute disease, 57% (4 of 7) with lymphoma, and 50% (2 of 4) for unfavorable chronic ATL. Patient responses according to disease site were 31% for target (nodal and extranodal) lesions, 75% for cutaneous lesions, and 60% for peripheral blood.
The median time to relapse was 1.9 months (range, 1.8-3.7 months), while the median time to progression was 3.8 months (95% CI, 1.9 to not estimable [NE]). The median and mean duration of response for the entire cohort were NE (95% CI, 0.5 months to NE) and 5.2 months (range, 0 to 16.6 months), respectively.
Progression-free survival was 3.8 months (95% CI, 1.9 months to NE) and for overall survival, it was 20.3 months (95% CI, 9.1 months to NE).
Adverse events occurred in more than 20% of patients and the most common hematologic event was thrombocytopenia (77%). The most common nonhematologic event was increased C-reactive protein (42%), and hypoalbuminemia and hypoproteinemia were observed in about a third of patients, as were constipation, hyponatremia, and hypocalcemia (all 31%).
Dr. Ishida and several coauthors reported multiple relationships with industry, including Celgene K.K. (Tokyo), the study’s sponsor.