Pfizer reports positive study results for potential biosimilar to Roche's Rituxan in lymphoma
Pfizer on Wednesday announced top-line results from a comparative Phase III study of its proposed biosimilar to Rituxan (rituximab), which Roche and Biogen co-market in the US, where the drug's patent is set to expire later this year. Pfizer said its experimental therapy, dubbed PF-05280586, demonstrated equivalence in overall response rate (ORR) for the first-line treatment of patients with low tumour burden, CD20-positive follicular lymphoma.
In the REFLECTIONS B3281006 study, participants were randomised to treatment with either PF-05280586 or Rituxan. The trial's primary endpoint is ORR defined according to the revised response criteria for malignant lymphoma at week 26.
Amrit Ray, global president of Pfizer's essential health R&D unit, commented "these results reinforce the potential of our proposed [Rituxan] biosimilar in providing a safe and effective treatment option for patients." The drugmaker indicated that it will present results from the study at a future research conference or in a journal.
Rituxan, which is sold as MabThera by Roche in the EU and other markets, except in Japan, where it is co-marketed by Chugai and Zenyaku Kogyo, amassed sales of about 7.3 billion Swiss francs ($7.7 billion) in 2016. Other biosimilars of the therapy have already been authorised in Europe, including Celltrion's Truxima and Novartis' Rixathon.
Roche is also expected to face growing biosimilar competition for other cancer drugs. Last month, the FDA approved Mylan's Ogivri (trastuzumab-dkst) as a biosimilar version of Roche's Herceptin (trastuzumab) to treat breast and stomach cancers, while Mylan's drug remains under review in Europe. Further, regulators in both the US and EU have also recently cleared Amgen's Mvasi (bevacizumab-awwb), a biosimilar version of Roche's Avastin (bevacizumab), for certain types of cancer.
Sales of Rituxan, Herceptin and Avastin accounted for more than half of Roche's pharmaceuticals business in 2016, together generating revenue of 20.9 billion francs ($21.8 billion). However, some analysts are forecasting that the products' combined sales will decline more than 40 percent by 2022.