nelarabine and Lymphoma--T-Cell--Peripheral

Nelarabine (compound 506U78), a novel purine nucleoside, is a soluble pro-drug of 9-beta-D-arabinofuranosylguanine (ara-G). Nelarabine is rapidly demethoxylated in blood by adenosine deaminase to ara-G. Pre-clinical and clinical studies have demonstrated the selective cytotoxicity of ara-G to T-lineage derived cells. CALGB Protocol 59901 was a Phase II study of nelarabine in patients with systemically untreated cutaneous T-cell lymphoma (CTCL) or refractory/relapsed systemic T-cell lymphoma (STCL). The objectives were to determine response rate, remission duration and safety profile associated with nelarabine given at 1.5 g m(-2) per day on days 1, 3 and 5 as an intravenous infusion every 21 days for a minimum of two cycles and to continue up to two cycles beyond CR up to a maximum of eight cycles. Nineteen patients were enrolled in the study: 11 CTCL and eight STCL patients. Grade 3 or 4 adverse events were documented in 50% and 28%, respectively. In particular, 33% of patients experienced Grade 3 or 4 neurologic toxicities. There were two partial remissions lasting 3 months and 5.5 months, respectively. Median event-free survival was 1.2 months and median overall survival was 3 months. Due to lack of efficacy and excessive toxicity, nelarabine is not recommended as monotherapy in adult patients with CTCL and STCL at this dose schedule.

Topics: Adult; Aged; Antineoplastic Agents; Arabinonucleosides; Disease-Free Survival; Female; Humans; Lymphoma, T-Cell, Cutaneous; Lymphoma, T-Cell, Peripheral; Male; Middle Aged; Prodrugs; Survival Analysis; Treatment Outcome

Peripheral T-cell lymphomas (PTCLs) are a rare and diverse group of neoplasms with a poor prognosis. Management of these disorders has been largely extrapolated from the treatment of aggressive B-cell lymphomas; however, therapeutic responses to this approach are neither adequate nor durable for most patients with PTCL. Given the rarity of PTCL, much of the literature consists of studies with small sample size and anecdotal case reports. Therefore, no consensus exists on the best therapeutic strategy for either newly diagnosed or relapsed/refractory PTCL. This article reviews promising novel approaches in the treatment of PTCL and its subtypes. Investigation into the pathogenesis of PTCL has also identified new targets for treatment. These emerging therapies include new uses of existing agents and the development of novel agents specifically targeted against T-cell lymphoma. Results using antimetabolites, immunotherapies, and histone deacetylase inhibitors have been particularly encouraging. These novel therapies are being tested as single agents and in combination with conventional lymphoma regimens in the frontline and salvage settings. Because of the rarity and heterogeneity of PTCL, national and international cooperation is needed to conduct the clinical studies required for the development of more effective treatment paradigms. These efforts are ongoing and will hopefully guide new strategies to improve the historically poor outcome of PTCL.

Topics: Alemtuzumab; Antibodies, Monoclonal; Antibodies, Monoclonal, Humanized; Antibodies, Neoplasm; Antineoplastic Agents; Arabinonucleosides; Deoxycytidine; Diphtheria Toxin; Gemcitabine; Histone Deacetylase Inhibitors; Humans; Immunosuppressive Agents; Interleukin-2; Lymphoma, T-Cell, Peripheral; Practice Guidelines as Topic; Protease Inhibitors; Purine Nucleosides; Purine-Nucleoside Phosphorylase; Pyrimidinones; Recombinant Fusion Proteins; Vascular Endothelial Growth Factor A