Roche presented updated, longer-term overall survival (OS) data from the Phase III STARGLO trial reinforcing what researchers said was a "statistically significant and clinically meaningful" survival benefit for the CD20xCD3 bispecific antibody Columvi (glofitamab) in earlier-line relapsed/refractory diffuse large B-cell lymphoma (DLBCL).
The results, unveiled Friday at the European Hematology Association (EHA) annual meeting, shed more light on top-line findings first reported in April showing Columvi plus chemotherapy hit the trial's primary endpoint of improved OS versus the Rituxan/MabThera (rituximab)-chemo combo. They also bolster Roche's case as it looks to broaden the drug's label into earlier-line settings.
Battle of bispecifics
Regulators last year in the US, Europe and Canada granted early approval to Columvi for third-line DLBCL patients based on response-rate data from a Phase I/II trial. The STARGLO readout will be key as Roche looks to set Columvi apart from rivals including AbbVie/Genmab's Epkinly (epcoritamab), a drug in the same class that is also authorised in third-line DLBCL.
The STARGLO study enrolled 274 people with relapsed or refractory DLBCLrelapsed or refractory DLBCL who received at least one prior line of therapy and are not candidates for autologous stem cell transplant. Participants were randomised to receive Columvi or Rituxan/MabThera, both in combination with gemcitabine plus oxaliplatin. Roughly two-thirds had been treated with just one prior therapy, while the remaining had received at least two.
Triumph on key survival measures
As of the primary analysis cutoff date of March 2023, Columvi was associated with an OS benefit of 41% compared to the comparator arm. It also showed a significant improvement in progression-free survival (PFS) of 63%, with complete response (CR) rates of 50.3% versus 22% for the Columvi and Rituxan/MabThera arms, respectively.
Once all patients had completed therapy, the follow-up analysis with a cutoff of February 16 this year, showed that the Columvi regimen continued to demonstrate superior median OS of 25.5 months versus 12.9 months for the comparator arm. That translated to an OS benefit of 38% in favour of Roche's CD20xCD3 bispecific. Columvi also bested Rituxan/MabThera on PFS with a benefit of 60% (13.8 vs 3.6 months), as well as CR rate (58.5% vs 25.3%).
However, the Columvi combo resulted in more adverse events (AEs) compared to the Rituxan regimen. Nearly 70% of Columvi patients experienced Grade 3 or 4 side effects versus 36% on Rituxan. In addition, around 8% of Columvi patients died during the study, compared to 4.5% with Rituxan – an imbalance that was driven by more COVID-19-related AEs. Adjusting for greater exposure, researchers noted that AE rates were similar between the arms.