Trial-in-Progress: Brentuximab Vedotin in Combination with Lenalidomide and Rituximab in Subjects with Relapsed or Refractory Diffuse Large B-Cell Lymphoma (DLBCL)
Authors: Bartlett Nancy L. , Yasenchak Christopher A. , Sims Robert B. , Nowakowski Grzegorz S. 
Published: November 2020

Background
Majority of patients with relapsed/refractory (R/R) diffuse large B-cell lymphoma (DLBCL) who relapse after HSCT, or who are not candidates for HSCT have poor outcomes and are in need of novel therapies. Preclinical data provides a strong rationale for combining brentuximab vedotin, lenalidomide, and rituximab in the treatment of R/R DLBCL. In a phase 1 trial, 37 subjects with R/R DLBCL were treated with brentuximab vedotin in combination with lenalidomide. The objective response rate (ORR) (proportion of subjects with complete response [CR] or partial response [PR]) for all subjects was 56.7% (21 of 37 subjects). For the CD30-positive population, the ORR was 73.3% (11 of 15 subjects), whereas the ORR for the CD30 &lt;1% population was 45.6% (10/22). The median follow-up time was 14.3 months (range: 1 to 56.7 months). The median duration of remission for subjects with CR or PR was 13.2 months (range: 3.2 to 55.2 months). For subjects with CR, PR, or stable disease (SD) &gt;6 months, the median duration of remission was 11.70 months (range: 3.2 to 55.2 months). The progression-free survival (PFS) and overall survival (OS) results appear similar in both the CD30-positive and CD30 &lt;1% groups. The PFS in the combined population is 10.2 months and the median OS is 14.2 months (manuscript in preparation).
Study Design and Methods
This is a randomized, double-blind, placebo-controlled, active-comparator, multicenter phase 3 study designed to evaluate the efficacy of brentuximab vedotin in combination with lenalidomide and rituximab versus placebo in combination with lenalidomide and rituximab for the treatment of subjects with R/R DLBCL (NCT04404283).
Key eligibility criteria include the following: subjects aged 18 and older with R/R DLBCL with an eligible subtype; subjects must have ≥2 prior lines of therapy and must be ineligible for, or have declined, stem cell transplant, and chimeric antigen receptor T-cell (CAR-T) therapy; subjects must have an ECOG performance status score of 0 to 2; subjects must have a fluorodeoxyglucose-avid disease by PET and bidimensional measurable disease of at least 1.5 cm by CT, as assessed by the site radiologist.
Subjects (n=400) will be randomized 1:1 to receive either brentuximab vedotin or placebo in combination with lenalidomide and rituximab and will be stratified by CD30 expression (positive [≥1%] versus &lt;1%), prior allogeneic or autologous stem cell transplant therapy (received or not), prior CAR-T therapy (received or not), and cell of origin (germinal-center B-cell-like (GCB) or non-GCB). Cell of origin (GCB or non-GCB) will be histologically determined by local pathology assessment.
Disease response will be assessed by a blinded independent central review (BICR) and the investigator according to the Lugano Classification Revised Staging System. Radiographic disease evaluations, including contrast-enhanced CT scans and PET/CT, will be assessed at baseline, then every 6 weeks from randomization for 12 months, then every 12 weeks (±3 days). PET/CTs will be discontinued if negative.
For the primary efficacy analyses of PFS per BICR in the intent-to-treat population and in CD30-positive subjects, the stratified log-rank test will be used to compare PFS between the 2 treatment groups. The hazard ratio will be estimated using a stratified Cox regression model. PFS will also be summarized using the Kaplan-Meier method. Similar methods will be used for the secondary efficacy endpoint of OS, and other time-to-event efficacy endpoints.
The trial will have sites open in the US and multiple countries in Europe and Asia, with enrollment planning to begin in the second half of 2020.

Disclosures
Bartlett: Roche/Genentech: Consultancy, Research Funding; Seattle Genetics: Membership on an entity's Board of Directors or advisory committees, Research Funding; Millennium: Research Funding; Pfizer: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Pharmacyclics: Research Funding; Seattle Genetics: Consultancy, Research Funding; Janssen: Research Funding; Kite, a Gilead Company: Research Funding; Merck: Research Funding; BTG: Consultancy; Acerta: Consultancy; Affimed Therapeutics: Research Funding; Immune Design: Research Funding; Forty Seven: Research Funding; BMS/Celgene: Research Funding; ADC Therapeutics: Consultancy; Autolus: Research Funding. Yasenchak:Takeda: Honoraria; BeiGene: Speakers Bureau; Seattle Genetics: Honoraria, Research Funding. Sims:Seattle Genetics, Inc.: Current Employment, Current equity holder in publicly-traded company, Other: Travel expenses. Nowakowski:Roche: Consultancy, Research Funding; Celgene/BMS: Consultancy, Research Funding; Kite: Consultancy; Denovo: Consultancy; Kymera: Consultancy; Ryvu: Consultancy, Membership on an entity's Board of Directors or advisory committees, Other; Curis: Consultancy; Seattle Genetics: Consultancy; Nanostrings: Research Funding; MorphoSys: Consultancy, Research Funding.