Rituximab Biosimilar Shows Equivalency in CD20+ Non-Hodgkin Lymphoma

David M. Reese, MD

ABP 798, a rituximab (Rituxan) biosimilar, demonstrated clinical equivalency to reference rituximab in patients with CD20-positive B-cell non-Hodgkin lymphoma, according to topline results from the comparative phase III JASMINE study (NCT02747043).¹

The primary endpoint, which was an assessment of objective response rate (ORR) at week 28, was within the prespecified margin for ABP 798 compared with rituximab. The safety and immunogenicity data with ABP 798 were similar to the reference product as well, Amgen and Allergan, the co-developers of the biosimilar, announced in a press release.

"Today's results with ABP 798 demonstrate another positive development from Amgen's robust pipeline of biosimilar medicines and we look forward to working with regulatory agencies to bring this treatment to patients," David M. Reese, MD, executive vice president of Research and Development at Amgen, stated in the press release. "We continue to leverage our deep expertise and heritage in biologics across innovative and biosimilar medicines as part of our commitment to providing a range of treatment options for patients with the most serious diseases, including cancer."

In the double-blind, comparative JASMINE trial, researchers evaluated the efficacy, safety, and immunogenicity of ABP 798 compared with rituximab in 256 adult patients with non-Hodgkin lymphoma. Patients received either ABP 798 or rituximab intravenously at 375 mg/m² once weekly for 4 weeks, followed by dosing at weeks 12 and 20.

To be eligible for enrollment, patients must have been ≥18 years old; have histologically confirmed grade 1, 2, or 3a follicular B-cell CD20-expressing non-Hodgkin lymphoma within 12 months prior to randomization; have stage II, III, or IV disease that is measurable; and have low tumor burden based on Groupe d'Etudes des Lymphomes Folliculaires criteria.

Those with diffuse large cell component and/or grade 3b follicular non-Hodgkin lymphoma; have a history or presence of central nervous system metastases; have another malignancy beyond non-Hodgkin lymphoma within 5 years; be treated with systemic anti-infective therapies for a recent infection; underwent other investigational procedures that can impact study results; had prior chemotherapy, biological or immunological therapy; and received systemic corticosteroid use within 3 months prior to randomization were excluded from enrolling on the trial.

Secondary endpoints include risk difference of ORR at week 12, percent of patients with complete CD19 cell count depletion and total IgG and IgM antibody levels, treatment-emergent and serious adverse events, incidence of anti-drug antibodies, progression-free survival, overall survival, and geometric mean ratio of test to reference rituximab.

Earlier data showed that ABP 798 was similar to reference rituximab sourced both from the United States and the European Union in relation to biological activity across a number of assays.² Such tests evaluated the major and minor mechanisms of action across the approved rituximab indications.

The JASMINE data are the second of two trials that are intended to support regulatory submissions for the rituximab biosimilar. A prior study, in which ABP 798 was evaluated in patients with moderate-to-severe rheumatoid arthritis, also met the primary endpoint of pharmacokinetic similarity.³

The announcement follows the July 2019 FDA approval of another rituximab biosimilar, PF-05280586 (rituximab-pvvr; Ruxience), for the treatment of adult patients with CD20-positive B-cell non-Hodgkin lymphoma as a single agent or in combination with chemotherapy, or for patients with CD20-positive chronic lymphocytic leukemia (CLL) in combination with chemotherapy.

The approval was based on a review of a comprehensive data package, which demonstrated biosimilarity of PF-05280586 to reference rituximab.⁴ The package includes data from the REFLECTIONS B3281006 clinical comparative trial, which showed there were no clinically meaningful differences in efficacy or safety compared with reference rituximab in patients with CD20-positive, low tumor burden follicular lymphoma.

In November 2018, the FDA approved the first rituximab biosimilar, CT-P10 (Truxima; rituximab-abbs), for the treatment of adult patients with CD20-positive, B-cell non-Hodgkin lymphoma as a single agent or in combination with chemotherapy.

CT-P10 has approved indications that are equivalent to reference rituximab, which includes: relapsed/refractory, low-grade or follicular lymphoma, CD20-positive B-cell non-Hodgkin lymphoma as a single agent; previously untreated follicular lymphoma, CD20-positive, B-cell non-Hodgkin lymphoma in combination with first-line chemotherapy and, in patients achieving a complete or partial response to a rituximab product in combination with chemotherapy, as single-agent maintenance therapy; and non-progressing or stable low-grade, CD20-positive, B-cell non-Hodgkin lymphoma as a single agent after frontline cyclophosphamide, vincristine, and prednisone chemotherapy.

References

1. Amgen And Allergan Announce Positive Top-Line Results From Comparative Clinical Study Of ABP 798, Biosimilar Candidate To Rituxan® (Rituximab). Amgen. Published August 22, 2019. https://bit.ly/2L0pACF. Accessed August 22, 2019.
2. McBride H, Maher G, Sweet H, Foltz I, Kuhns S. Functional similarity of proposed biosimilar ABP 798 with rituximab. Blood. 2017;130:5001. bloodjournal.org/content/130/Suppl_1/5001.
3. Amgen And Allergan Announce Positive Top-Line Results From Phase 1/ Phase 3 Study Of ABP 798, Biosimilar Candidate To Rituximab. Amgen. Published January 24, 2019. https://bit.ly/2FVzjct. Accessed January 24, 2019.
4. FDA Approves Pfizer’s Biosimilar, RUXIENCE (rituximab-pvvr), for Certain Cancers and Autoimmune Conditions. Pfizer. Published July 23, 2019. https://bwnews.pr/2Sxzvmo. Accessed July 23, 2019.