Comparative efficacy and tolerability of novel agents vs chemotherapy in relapsed and refractory T-cell lymphomas: a meta-analysis

Optimal treatment strategies for (relapsed and refractory [R/R]) peripheral T-cell lymphoma (PTCL) have not been well defined, and with the approval of several novel single agents (SA), the comparative efficacy of combination chemotherapy (CC) to single-agent strategies remains unclear. We conducted a meta-analysis to evaluate overall response rates (ORR) and toxicities of SA to CC. MEDLINE, Embase, Web of Science Core Collection, and Cochrane were systematically searched for phase I, phase II, and phase III trials investigating a defined SA or an anthracycline-, ifosfamide-, gemcitabine-, and platinum-based regimens. One hundred and fifty-one articles were included, encompassing single and combinations of 60 phase I trials involving 1075 patients, 95 phase II trials involving 3246, and 23 phase III trials involving 1888 patients. There was a high degree of heterogeneity in the trials. Using a random-effects model, the estimated ORR for SA in phase I trials were 40% (95% confidence interval [CI], 34.7%, 46.9%) relative to 41% for CC (95% CI, 27.4%, 56.1%; P = .97) and in phase II trials 34.4% (95% CI, 30.4%, 38.7%) for SA vs 55.3% (95% CI, 31%, 77.2%; P = .1) for CC. There were significant subgroup differences in ORR between histological subtypes of PTCL and drug classes. Our results highlight SA as an attractive outpatient option for R/R PTCL, and their incorporation in the development of upfront treatment paradigms merits urgent consideration. Our results underscore enrollment in clinical trials of SA as a critical strategy for R/R PTCL.