The Echelon-2 Trial: 5-Year Results of a Randomized, Double-Blind, Phase 3 Study of Brentuximab Vedotin and CHP (A+CHP) Versus CHOP in Frontline Treatment of Patients with CD30-Positive Peripheral T-Cell Lymphoma

Objective Brentuximab vedotin (BV) plus cyclophosphamide, doxorubicin, and prednisone (A+CHP) significantly prolonged progression-free survival (PFS) and overall survival (OS) versus cyclophosphamide, doxorubicin, vincristine, and prednisone (CHOP) in patients with systemic anaplastic large-cell lymphoma (sALCL) or other CD30-positive peripheral T-cell lymphomas (PTCL) in ECHELON-2 (Horwitz S et al., Lancet 2019). We report updated results; median follow-up was 47.6 months for PFS and 66.8 months for OS. Design This phase 3, double-blind study (NCT01777152) randomized patients aged ≥18 years with previously untreated CD30-positive PTCL (targeting 75% ± 5% with sALCL) to A+CHP or CHOP for 6 or 8 cycles. Primary endpoint of PFS was assessed per investigator in this updated analysis. Key secondary endpoints included OS and PFS in sALCL. BV or BV-containing regimens were permitted as subsequent/retreatment therapies. Results 452 patients were enrolled (226 patients in each arm); 316 (70%) patients had sALCL. Patients with advanced disease were included (stage III [27%] and stage IV [53%]; International Prognostic Index ≥2 [78%]). Data continues to favor A+CHP: HRs were 0.70 (95% CI: 0.53–0.91, P=0.0077) for PFS per investigator and 0.72 (95% CI: 0.53–0.99, P=0.0424) for OS. 5-year PFS was 51.4% (95% CI: 42.8–59.4) with A+CHP versus 43.0% (95% CI: 35.8–50.0) with CHOP; median PFS was 62.3 months (95% CI: 42.0–not evaluable) with A+CHP and 23.8 months (95% CI: 13.6–60.8) with CHOP. 5-year OS was 70.1% (95% CI: 63.3–75.9) and 61.0% (95% CI: 54.0–67.3) with A+CHP and CHOP, respectively. Median OS was not reached in either arm. PFS favored A+CHP (HR: 0.55 [95% CI: 0.39–0.79]) in sALCL. 29 (13%) and 54 (24%) patients with A+CHP and CHOP received subsequent BV, respectively. Treatment-emergent peripheral neuropathy (PN), resolved/improved in 72% (n=84/117) and 78% (n=97/124) of patients with PN on A+CHP and CHOP, respectively; 98% and 97% of ongoing PN events were grade 1/2 with A+CHP and CHOP, respectively. Conclusions At this important 5-year milestone, A+CHP still provides clinically meaningful improvement in both PFS and OS versus CHOP, with a manageable safety profile, including continued resolution/improvement of PN. Funded by NIH/NCI Support Grant P30 CA008748.