Study Analyzing Daratumumab to Treat Patients with Multiple Myeloma Induces Positive Topline Results

The second part of the phase 3 CASSIOPEIA trial produced positive topline results in its examination of daratumumab (Darzalex) monotherapy as maintenance treatment for patients with newly diagnosed multiple myeloma who are eligible for autologous stem cell transplant (ASCT), according to an announcement by Genmab.¹

The study’s second part met its primary end point of improving progression free survival at a pre-planned interim analysis (HR, 0.53; 95% CI, 0.42-0.68; P < .0001), which resulted in a 47% reduction in the risk of disease progression or death for patients treated with the monotherapy.

“Following the positive data from the first part of the CASSIOPEIA study, we are very pleased to see this benefit,” said chief executive officer of Genmab, Jan van de Winkel, PhD, in a press release. “We are appreciative of the efforts of the IFM, of HOVON and of Janssen for their work on this study.”

The data was collected from 1085 newly diagnosed patients with previously untreated symptomatic multiple myeloma eligible for high dose chemotherapy and ASCT.

The first part of the study randomized the cohort of patients to receive induction and consolidation treatment with daratumumab combined with bortezomib, thalidomide and dexamethasone (VTd) or VTd alone, with a primary end point of the number of patients that achieved a stringent complete response (sCR).

More, part 1 of the study showed that D-VTd before and after ASCT improved depth of response and progression-free survival, while maintaining an acceptable safety profile. The researchers claim that this study is the first of its kind to show the “clinical benefit of daratumumab plus standard of care in transplant-eligible patients with newly diagnosed multiple myeloma.”²

Then, for the second part of the research, the patients who achieved a response to the monotherapy underwent a second randomization to receive maintenance treatment of daratumumab or no further treatment.

The CASSIOPEIA trial is a randomized, open-label, multicenter phase 3 study being conducted by the French Intergroupe Francophone du Myelome (IFM) in collaboration with the Dutch-Belgian Cooperative Trial Group for Hematology Oncology (HOVON) and Janssen Research & Development, LLC.

It was recommended that the results be unblinded following the results at a pre-planned interim analysis conducted by an Independent Data Monitoring Committee (IDMC). Janssen plans to submit the data to an upcoming medical conference and for publication in a peer reviewed journal.

Multiple myeloma is the third most common blood cancer in the United States. Approximately 26,000 people were expected to be diagnosed with the incurable blood cancer in the United States in 2018, with approximately 13,650 dying from the disease. The disease starts in the bone marrow and can cause symptoms such as bone problems, low blood counts, calcium elevation, kidney problems or infections.

Reference:

1. Genmab Announces IFM, HOVON and Janssen Achieve Positive Topline Results in Second Part of Phase 3 CASSIOPEIA Study of Daratumumab in Multiple Myeloma at Pre-planned Interim Analysis [news release]. Copenhagen, Denmark. Published October 21, 2020. https://ir.genmab.com/news-releases/news-release-details/genmab-announces-ifm-hovon-and-janssen-achieve-positive-topline. Accessed October 22, 2020.

2. Moreau P, Attal M, Hulin C, et al. Bortezomib, thalidomide, and dexamethasone with or without daratumumab before and after autologous stem-cell transplantation for newly diagnosed multiple myeloma (CASSIOPEIA): a randomised, open-label, phase 3 study. The Lancet. https://doi.org/10.1016/S0140-6736(19)31240-1.