Background
CASSIOPEIA was a phase III open-label randomized trial (two-part design) evaluating daratumumab plus bortezomib-thalidomide-dexamethasone (D-VTd) versus VTd as induction and consolidation therapy flanking autologous stem cell transplantation (ASCT) in transplant-eligible newly diagnosed multiple myeloma (NDMM). VTd was the European standard induction regimen at the time; CASSIOPEIA tested whether CD38-directed antibody augmentation of VTd could improve post-transplant response depth and PFS.
Interventions and follow up
Arm A (VTd): Bortezomib 1.3 mg/m² + thalidomide 100 mg + dexamethasone induction × 4 cycles → ASCT → VTd consolidation × 2 cycles → Part 2 randomization to dara maintenance or observation
Arm B (D-VTd): Daratumumab 16 mg/kg + bortezomib + thalidomide + dexamethasone induction × 4 cycles → ASCT → D-VTd consolidation × 2 cycles → Part 2 randomization to dara maintenance or observation
Primary endpoint: Stringent complete response (sCR) rate at Day 100 after ASCT
Secondary: PFS, MRD negativity
mFollow-up: 18.8 months (Part 1)
Arm B (D-VTd): Daratumumab 16 mg/kg + bortezomib + thalidomide + dexamethasone induction × 4 cycles → ASCT → D-VTd consolidation × 2 cycles → Part 2 randomization to dara maintenance or observation
Primary endpoint: Stringent complete response (sCR) rate at Day 100 after ASCT
Secondary: PFS, MRD negativity
mFollow-up: 18.8 months (Part 1)
Results
sCR rate (Day 100): 29.4% vs 19.9% (OR 1.60, 95% CI 1.21–2.12, P=.0010)
18-mo PFS: 92.7% vs 84.9% (HR 0.47, 95% CI 0.33–0.67, P<.0001)
MRD negativity (10⁻⁵): 63.9% vs 43.8%
Part 2 maintenance: dara maintenance improved PFS vs observation (4-yr PFS 71% vs 57%, HR 0.53)
18-mo PFS: 92.7% vs 84.9% (HR 0.47, 95% CI 0.33–0.67, P<.0001)
MRD negativity (10⁻⁵): 63.9% vs 43.8%
Part 2 maintenance: dara maintenance improved PFS vs observation (4-yr PFS 71% vs 57%, HR 0.53)
Adverse events
Overall: Grade ≥3 AEs 83.7% vs 78.4%; no new unexpected safety signals
Infusion-related: reactions 26.8% (Grade ≥3: 3.7%)
Infectious: infections Grade ≥3 24.7% vs 18.1%
Other: thromboembolic events and peripheral neuropathy (thalidomide-related) similar between arms
Infusion-related: reactions 26.8% (Grade ≥3: 3.7%)
Infectious: infections Grade ≥3 24.7% vs 18.1%
Other: thromboembolic events and peripheral neuropathy (thalidomide-related) similar between arms
Conclusions
D-VTd induction and consolidation around ASCT significantly improved sCR rate at Day 100 post-transplant and 18-month PFS compared to VTd, with deeper MRD negativity, establishing daratumumab augmentation of VTd as a superior transplant-eligible NDMM induction regimen, and daratumumab maintenance post-consolidation as beneficial in Part 2.
Key Limitations
European trial using VTd backbone (not widely used in the US, where VRd is preferred — see GRIFFIN for D-VRd data); thalidomide included in VTd (largely replaced by lenalidomide in the US and increasingly globally); Part 1 primary endpoint is sCR rate (surrogate), not PFS or OS; Part 2 maintenance analysis was exploratory by design; daratumumab administered IV (SC formulation not used); no quadruplet consolidation comparison; no direct GRIFFIN vs CASSIOPEIA comparison possible due to different induction backbones and phase designs.
Clinical Context
CASSIOPEIA provided the pivotal evidence for daratumumab-based induction in transplant-eligible NDMM in Europe, supporting EMA/FDA approval. In the US, GRIFFIN (Phase II, VRd backbone) provided complementary evidence for D-VRd. The subsequent PERSEUS trial (Phase III, D-VRd vs VRd) provided definitive Phase III evidence for the VRd-based quadruplet approach in the US/global context (Sonneveld P, NEJM 2024). Together, CASSIOPEIA, GRIFFIN, and PERSEUS established the quadruplet daratumumab + PI + IMiD + dex induction as the new standard for transplant-eligible NDMM per ASCO/ESMO guidance.