Evaluation of complete response rate at 30 months (CR30) as a surrogate for progression-free survival (PFS) in first-line follicular lymphoma (FL) studies: Results from the prospectively specified Follicular Lymphoma Analysis of Surrogacy Hypothesis (FLASH
PURPOSEPatients with indolent non-Hodgkin lymphoma typically respond well to first-line immunochemotherapy. At relapse, single-agent rituximab is commonly administered. Data suggest the immunomodulatory agent lenalidomide could increase the activity of rituximab.METHODSA phase III, multicenter, randomized trial of lenalidomide plus rituximab versus placebo plus rituximab was conducted in patients with relapsed and/or refractory follicular or marginal zone lymphoma. Patients received lenalidomide or placebo for 12 cycles plus rituximab once per week for 4 weeks in cycle 1 and day 1 of cycles 2 through 5. The primary end point was progression-free survival per independent radiology review.RESULTSA total of 358 patients were randomly assigned to lenalidomide plus rituximab (n = 178) or placebo plus rituximab (n = 180). Infections (63% v 49%), neutropenia (58% v 23%), and cutaneous reactions (32% v 12%) were more common with lenalidomide plus rituximab. Grade 3 or 4 neutropenia (50% v 13%) and leukopenia (7% v 2%) were higher with lenalidomide plus rituximab; no other grade 3 or 4 adverse event differed by 5% or more between groups. Progression-free survival was significantly improved for lenalidomide plus rituximab versus placebo plus rituximab, with a hazard ratio of 0.46 (95% CI, 0.34 to 0.62; P < .001) and median duration of 39.4 months (95% CI, 22.9 months to not reached) versus 14.1 months (95% CI, 11.4 to 16.7 months), respectively.CONCLUSIONLenalidomide improved efficacy of rituximab in patients with recurrent indolent lymphoma, with an acceptable safety profile.
Phase I/II study of durvalumab (anti–PD-L1 antibody) as monotherapy and in combination in patients with lymphoma or chronic lymphocytic leukemia.
TPS7574 Background: The PD-1/PD-L1 pathway is an important immune checkpoint used by tumor cells to evade immune cell detection and inhibit antitumor responses. PD-1/PD-L1 expression in multiple hematologic malignancies may provide an effective target for enhancing anticancer immune response. Durvalumab (MEDI4736) is a high-affinity human IgG1 monoclonal Ab that selectively blocks PD-L1 binding to PD-1 and CD80, and has shown preliminary evidence of antitumor activity across multiple tumor types. Study objectives are to evaluate durvalumab monotherapy and combinations to determine dose and safety, as well as identify histologies and combinations that show the best complementary antitumor signals for future study. Methods: This is a phase I/II open-label, global, multicenter study of durvalumab as a monotherapy and in combination in relapsed/refractory B-cell lymphoma or CLL (MEDI4736-NHL-001; EUDRA CT 2015-003516-21; NCT02733042). Patients must have histologically-confirmed FL, MCL, splenic or nodal MZL, T-cell/histiocyte rich BCL, PMBCL, ALK+ large BCL, transformed large BCL, Richter’s transformation, DLBCL (NOS), CLL/SLL, or classical HL during the dose-finding part. Inclusion criteria are ECOG PS 0-2, and ≥1 prior antilymphoma therapy. Up to 253 patients may enroll in 4 treatment arms, which include fixed-dose durvalumab 1500 mg Q4W monotherapy or combinations with lenalidomide/rituximab, ibrutinib, or bendamustine/rituximab. The study has 3 parts: dose finding, dose confirmation, and dose expansion. The monotherapy arm does not have a dose finding or expansion part; upon progression, patients may receive combination therapy or involved-field radiation to a single nodal site (evaluating for systemic abscopal antitumor effect). Primary endpoints are safety, identification of recommended phase II dose (phase I, 3+3 design), and overall response rate (ORR; phase II); secondary endpoints include DOR, PFS, and PK/PD. ORR is measured by 2014 IWG criteria for lymphoma or modified 2008 iwCLL criteria for CLL; safety is assessed per NCI CTCAE v4.03 criteria. Recruitment is ongoing, with a target enrollment of 253 patients across 60-80 centers globally. Clinical trial information: NCT02733042.
Thirty-Month Complete Response as a Surrogate End Point in First-Line Follicular Lymphoma Therapy: An Individual Patient-Level Analysis of Multiple Randomized Trials
Purpose Follicular lymphoma (FL) is an indolent cancer, with effective but rarely curative treatment options. As a standard study end point for first-line FL therapy, progression-free survival (PFS) requires extended follow-up (median PFS, > 7 years). To provide patients with earlier access to newer therapies, an earlier end point to expedite clinical trials is needed. Our objective was to formally assess the complete response rate at 30 months (CR30) after initiation of induction therapy as a potential surrogate end point for PFS in first-line FL therapy. Patients and Methods We analyzed individual patient data from 13 randomized multicenter trials of induction and maintenance regimens in first-line FL therapy published after 1990 and with sufficient data to evaluate whether CR30 could predict treatment effects on PFS. Correlation of the CR30 odds ratio with the PFS hazard ratio was evaluated by both linear regression (R2WLS) and bivariate copula (R2Copula) models. Prespecified criteria for surrogacy required either R2WLS or R2Copula ≥ 0.80, with a lower-bound 95% CI > 0.60. Results Data from eight induction and five maintenance randomized trials in 3,837 evaluable patients were analyzed. The prespecified surrogacy threshold was met, with an R2WLS of 0.88 (95% CI, 0.77 to 0.96) and an R2Copula of 0.86 (95% CI, 0.72 to 1.00). Multiple sensitivity and supplemental analyses supported the robustness of the findings. A minimum 11% absolute improvement in CR30 from a 50% control rate predicted a significant treatment effect on PFS (hazard ratio, 0.69). Conclusion This large, prospective, pooled analysis of randomized chemotherapy, immunotherapy, and chemoimmunotherapy trials demonstrates that CR30 is a surrogate end point for PFS in first-line FL treatment trials. Use of this end point may expedite therapeutic development with the intent of bringing novel therapies to this patient population years before PFS results are mature.