R‐THP‐COP versus R‐CHOP in patients younger than 70 years with untreated diffuse large B cell lymphoma: A randomized, open‐label, noninferiority phase 3 trial

Abstract Pirarubicin (tetrahydropyranyl adriamycin [THP]) is an anthracyclin with less cardiotoxicity than doxorubicin (DOX). We previously reported the efficacy and safety of R‐THP‐COP consisting of rituximab (R), THP, cyclophosphamide (CPA), vincristine (VCR), and prednisolone (PSL) for diffuse large B cell lymphoma (DLBCL) in phase 2 studies. Here, we prospectively compared the efficacy and safety of the R‐THP‐COP and standard R‐CHOP regimen (consisting of R, CPA, DOX, VCR, and PSL) in a noninferiority phase 3 trial. This prospective, randomized phase 3 study included patients younger than 70 years of age with previously untreated DLBCL. The regimen consisted of R (day 1), DOX, or THP (day 3), CPA (day 3), VCR (day 3), and PSL for 5 days every 3 weeks for 6 to 8 cycles. Between July 5, 2006 and June 11, 2013, 81 patients were randomly assigned to the treatment groups (R‐CHOP group, 40 patients; R‐THP‐COP group, 41 patients). R‐THP‐COP was noninferior to R‐CHOP, as assessed by the primary endpoint of complete response rate (85% vs 85% respectively). With a median follow‐up of 75.2 months, the 5‐year overall survival was 87% in the R‐CHOP group and 82% in the R‐THP‐COP group (hazard ratio [HR]: 0.89, 95% confidence interval [CI]: 0.31‐2.49; P = .82). The 5‐year progression‐free survival was 74% in the R‐CHOP group and 79% in the R‐THP‐COP group (HR: 1.37, 95% CI: 0.56‐3.55; P = .49). No grade 3 cardiac side effects were observed in either group. No serious late adverse reactions were observed in either group, with the exception of therapy‐related acute myeloid leukemia in the R‐THP‐COP group. These data indicate that R‐THP‐COP is noninferior to R‐CHOP with regard to clinical response, and has an acceptable safety profile. Thus, this regimen may be an alternative therapy to R‐CHOP.