Pfizer has reported positive 26-week data from the ongoing Phase III REFLECTIONS B328-06 trial evaluating the safety and efficacy of PF-05280586 in comparison with rituxan / mabthera (rituximab-EU) for the first-line treatment of patients with CD20-positive, low tumour burden, follicular lymphoma.
The 26-week data showed that the trial met its primary endpoint of overall response rate (ORR).
It showed no clinically meaningful differences in efficacy between PF-05280586 and mabthera among the 394 enrolled patients.
ORR was reported to be 75.5% at 26 weeks in patients treated with PF-05280586 against 70.7% in patients receiving rituximab.
The estimated rates of one-year progression-free survival were reportedly consistent across the PF-05280586 and mabthera groups.
Results demonstrated that both PF-05280586 and mabthera had a similar safety profile.
US Oncology Hematology Research medical director Dr Jeff Sharman said: “It is encouraging to see new data supporting a potential rituximab biosimilar.
“If approved this may help provide a more cost-effective treatment option and expand access for patients and physicians.
“The data presented today will help us understand the nuances of the medicine without the confounding influence of additional concurrent treatments.”
The REFLECTIONS B328-06 study comprises a randomised, 52-week double-blind clinical trial design that aims to assess the efficacy, safety and immunogenicity, pharmacokinetics and pharmodynamics of PF-05280586 against mabthera.
PF-05280586 is an investigational monoclonal antibody (mAb) that is being developed as a potential biosimilar to rituxan / mabthera.