June 2019 was a busy month for oncology biosimilars, in both the supportive care and anticancer contexts, with regulatory activity and the presentation of reassuring new data.
June drew to a close with news that the FDA had approved Pfizer’s bevacizumab biosimilar, Zirabev. The 21st US biosimilar, approved as bevacizumab-bvzr, references Avastin.
The biosimilar drug is also approved in the European Union, although it is not clear when Zirabev will make its way to patients in the EU or US contexts; Pfizer was dealt a blow this month when a UK court declined to issue a declaration that would allow for greater certainty about the patent landscape in Europe. Pfizer has said that its launch of the product is being thwarted by patent thickets around the reference product.
Among the other key developments of this month was the FDA’s approval of Amgen’s Kanjinti, or ABP 980. The trastuzumab biosimilar, approved for the treatment of HER2-positive breast cancer and gastric cancer, had previously been issued a Complete Response Letter in 2018. The biosimilar’s approval came just a week after researchers reported new cardiac safety data that demonstrate that the biosimilar and its reference have similar tolerability and safety.
Other new data on biosimilar trastuzumab agents were also unveiled at the American Society of Clinical Oncology (ASCO) annual meeting this month; Samsung Bioepis reported that, at 3 years, there was no difference in event-free survival (EFS) between patients treated with biosimilar trastuzumab, Ontruzant, and those treated with Herceptin that was not affected by a change in antibody-dependent cell-mediated cytotoxicity (ADCC).
Patients who were exposed to low-ADCC Herceptin, however, had decreased EFS. These findings have raised questions about what triggered the shift in the critical quality attribute for the reference drug, and whether other drugs that have had abrupt changes in their biological profiles—including the reference rituximab—may also be of concern.
New data on Mylan and Biocon’s biosimilar trastuzumab, Ogivri, were also made available this month: The final overall survival (OS) results of the HERITAGE study showed comparable OS for patients treated with the biosimilar and those treated with the reference. In other good news for Biocon, the company’s Bengaluru site, where it manufactures Ogivri, received EU certification of good manufacturing practice after a March 2019 inspection.
More biosimilar trastuzumab products are also on the horizon; the European Medicines Agency this month accepted for review a marketing authorization application from Henlius, a China-based biosimilar developer, for its HLX02.
Biosimilar rituximab was also a hot topic this month; data from Sandoz’s REFLECT trial of biosimilar rituximab, Rixathon, have been as expected in terms of safety, and 4 studies presented during the 24th European Hematology Association (EHA) Congress reported that Celltrion’s biosimilar rituximab, Truxima, did not negatively impact the effect of treatment, did not lead to unexpected adverse events, allowed a high proportion of patients with diffuse large B-cell lymphoma to achieve complete response or partial response, and generated substantial savings for European healthcare systems.
Data from the ASCO meeting also showed that European providers are growing more accepting of biosimilar rituximab, and uptake has been particularly strong in Germany and the United Kingdom.
Eli Lilly and Innovent hope to bring their own biosimilar rituximab, IBI301, to the market in China; the partnership announced this month that the National Medical Products Administration has accepted their regulatory application for review.
In the supportive care space, data from the ASCO meeting have shown that patients still worry that less expensive neutropenia drugs could be of reduced quality. Those findings could be of concern for drug makers like Sandoz, Fresenius Kabi, and Gema Biotech, all of whom recently gave updates on their biosimilar pegfilgrastim programs.
Finally, despite such worries, more data continue to accrue for the safety and efficacy of biosimilar granulocyte colony-stimulating factor agents. At the EHA meeting, researchers presented data on biosimilar filgrastim in the treatment of severe chronic neutropenia, reporting that no cases of osteoporosis, severe splenomegaly, splenic rupture, severe side effects, or immunogenicity have been reported in patients who received biosimilar filgrastim therapy.