The rituximab biosimilar CT-P10 has equivalent efficacy, compared with rituximab, and is well tolerated in the treatment of low–tumor-burden follicular lymphoma, according to results from a multinational, randomized, phase 3 study.
Overall response after 7 months of treatment exceeded 80% for patients assigned to CT-P10 and for those assigned to rituximab, investigators reported in the Lancet Haematology.
Adverse event profiles were comparable for rituximab and the biosimilar over that time period, while pharmacokinetics, pharmacodynamics, and immunogenicity were likewise comparable between arms, according to investigators.
“Thus, CT-P10 monotherapy is suggested as a new therapeutic option for patients with low–tumor-burden follicular lymphoma,” wrote senior author Larry W Kwak, MD, PhD, of the Comprehensive Cancer Center, City of Hope, Duarte, Calif., and his colleagues.
CT-P10, the first rituximab biosimilar to be authorized by the European Medicines Agency, has been recommended for approval in the United States by the Food and Drug Administration’s Oncologic Drugs Advisory Committee.
If approved by the FDA, CT-P10 would be the first rituximab biosimilar available in the United States, according to the company, which noted three proposed indications in non-Hodgkin lymphoma.
In the current randomized, double-blind, parallel-group, phase 3 trial, 258 patients with stage II-IV low–tumor-burden follicular lymphoma were randomly assigned to CT-P10 (130 patients) or rituximab sourced in the United States (128 patients).
Treatment consisted of an induction period of intravenous CT-P10 or rituximab weekly for 4 weeks, while patients experiencing disease control went on to a maintenance phase with their assigned treatment given every 8 weeks for six cycles, followed by another year of maintenance therapy with CT-P10 for those still on study.
The primary endpoint of the study was overall response at 7 months, defined as a complete response, unconfirmed complete response, or partial response.
Overall response was seen in 83% of patients randomized to CT-P10 and 81% of patients randomized to rituximab at 7 months, Dr. Kwak and his colleagues reported.
The two treatments were deemed therapeutically equivalent, as illustrated by 90% confidence intervals within a prespecified equivalence margin of 17%, investigators said.
The most common treatment-emergent adverse events in either group were infusion-related reactions, which were of grade 1-2, except for one grade 3 reaction reported in the CT-P10 group, according to the report. Other common adverse events were upper respiratory tract infections and fatigue.
Serious adverse events were reported in six patients in the CT-P10 arm and three patients in the rituximab arm.
The availability of a rituximab biosimilar is anticipated to reduce the cost of treatment and improve patient access, according to investigators.
Introduction of CT-P10 in the European Union was projected to save between 90 and 150 million euros over a year, enabling more than 12,500 new patients to be treated with the biosimilar, according to results of a budget impact analysis investigators cited in their report.
“Widespread adoption of a rituximab biosimilar could have a substantial effect on health care budgets and might also have effects at a societal level,” Dr. Kwak and his coauthors said in the report.
The trial was sponsored by Celltrion and three coauthors of the study were employees of the company. Dr. Kwak and several other coinvestigators not employed by Celltrion reported disclosures related to the company. Other disclosures provided related to Novartis, Roche, AbbVie, Celgene, and Takeda, among other entities.
SOURCE: Ogura M et al. Lancet Haematol. 2018 Nov;5(11):e543-53.