Safety and Efficacy of Polatuzumab Vedotin + Obinutuzumab for Relapsed/Refractory NHL: A Phase 1b/2 Study

Abstract

Background: Single-agent polatuzumab vedotin (pola) and obinutuzumab (G) demonstrated safety/clinical activity in separate B-cell non-Hodgkin lymphoma (B-NHL) trials. Methods: Open-label, non-randomised, phase 1b/2 study (ROMULUS) of patients with relapsed/refractory (R/R) B-NHL evaluating safety/efficacy of pola 1·8 mg/kg + G 1000 mg in 21-day cycles, up to eight cycles. Primary objectives were safety/tolerability and anti-tumour response. Findings: Eighty-eight patients were enrolled and received ≥1 dose of any study drug; 43 patients with R/R follicular lymphoma (FL) and 45 with R/R diffuse large B-cell lymphoma (DLBCL). Grade 3–4 AEs occurred in 48·5% (n=48/88) of patients, most commonly, neutropenia (18·6%; n=18). In R/R FL, the most frequent any-grade adverse event (AE) was fatigue (n=23/43; 53·5%) and in R/R DLBCL diarrhoea (n=16/45; 35·6%). In R/R FL, the complete response (CR) rate (by independent review committee) was 36·1% (n=13/36; 90% confidence interval [CI]: 22·9–51·2) with an objective response rate (ORR) of 66·7% (n=24/36; 90% CI: 51·7–79·5). The ORR in R/R DLBCL was 19·4% (n=6/31; 90% CI: 8·8–34·7; no CRs). In R/R FL, investigator-assessed median duration of response was 8·5 months (interquartile range [IQR]: 6×3–9×7) and in R/R DLBCL was 3·7 months (IQR: 3×3–not estimable [NE]); median progression-free survival was 11·5 months (IQR: 7×8-12×4) and 2·8 months (IQR: 1×5-6×3); and median overall survival was not reached and 10·7 months, respectively. Interpretation: While the anti-tumour activity of pola (1.8 mg/kg)-G in R/R DLBCL was modest, pola-G warrants further investigation as a treatment for R/R FL. Trial Registration: www.clinicaltrials.gov (NCT01691898). Funding Statement: F. Hoffmann-La Roche. Declaration of Interests: T.P. has received research support from AbbVie and Pharmacyclics, and reports advisory board participation for Genentech, Inc., Bayer, Gilead, Pharmacyclics, Incyte, and Seattle Genetics. M.B. has no disclosures; the clinical and intellectual work on this paper was performed prior to employment with the Cigna Corporation and does not reflect the opinions or support of the Cigna Corporation. A.I.C. has acted as a consultant and has received research funding from Genentech, Inc. J.E. has nothing to disclose. A.C. reports advisory board participation for Celgene, Janssen, and iQone, and has received lecture fees from Celgene, Janssen, F. Hoffman-La Roche Ltd, and Servier. C.D. has served as a consultant/advisory board participant for Bristol-Myers Squibb, Celgene, Merck, Genentech, Inc./F. Hoffman-La Roche Ltd, and Seattle Genetics, and has received research support from Seattle Genetics, Bristol-Myers Squibb, Merck, Genentech, Inc., Incyte, LAM Therapeutics, Millennium/Takeda, MEI Pharma, and Trillium. J.C. is an employee of F. Hoffmann-La Roche Ltd. D.R. was a consultant to Genentech, Inc. at the time the study was carried out. J.H. is an employee of Genentech, Inc. F.M. has participated in advisory boards for Celgene, F. Hoffman-La Roche Ltd, Gilead, Bristol-Myers Squibb, Epizyme, and Bayer, and reports receiving lecture fees from Celgene, Janssen, F. Hoffman-La Roche Ltd, and Novartis, and research support from AbbVie, Pharmacyclics, and advisory board fees from Genentech, Inc., Bayer, Gilead, Pharmacyclics, Incyte, and Seattle Genetics. I.W.F. has acted as a consultant for AbbVie, Seattle Genetics, TG Therapeutics, and Verastem Oncology, and has received research funding from Acerta Pharma, Agios, Calithera Biosciences, Celgene, Constellation Pharmaceuticals, Genentech, Inc., Gilead Sciences, Incyte, Infinity Pharmaceuticals, Janssen, Karo Pharma, Kite Pharma, Novartis, Pharmacyclics, Portola Pharmaceuticals, F. Hoffman-La Roche Ltd, TG Therapeutics, Trillium Therapeutics, AbbVie, ArQule, BeiGene, Curis Inc., FORMA Therapeutics, Forty Seven, Merck, Pfizer, Takeda, Teva, Verastem Oncology, Gilead Sciences, Astra Zeneca, Juno Therapeutics, Unum Therapeutics, and MorphoSys AG. Ethics Approval Statement: Institutional review boards/ethics committees approved the protocol. The study was conducted in accordance with the principles of the Declaration of Helsinki, the International Council for Harmonisation guidelines for Good Clinical Practice, and country-specific laws and regulations. All patients provided written informed consent.