The US Food and Drug Administration (FDA) has approved obinutuzumab (Gazyva) for certain patients with previously treated follicular lymphoma (FL).
Obinutuzumab is a glycoengineered, humanized, monoclonal antibody that selectively binds to the extracellular domain of the CD20 antigen on B cells.
The drug was previously approved by the FDA for use in combination with chlorambucil to treat patients with previously untreated chronic lymphocytic leukemia.
Now, obinutuzumab is approved for use in combination with bendamustine, followed by obinutuzumab alone, to treat patients with FL who did not respond to a rituximab-containing regimen or whose FL returned after such treatment.
The recommended dose and schedule for the regimen is:
- Obinutuzumab at 1000 mg by intravenous infusion on days 1, 8, and 15 of cycle 1; on day 1 of cycles 2-6 (28-day cycles); then every 2 months for 2 years.
- Bendamustine at 90 mg/m2 by intravenous infusion on days 1 and 2 of cycles 1-6.
Full prescribing information for obinutuzumab is available on the FDA website or at www.Gazyva.com.
Phase 3 study
The approval for obinutuzumab in FL is based on results from the phase 3 GADOLIN study. The trial included 413 patients with rituximab-refractory non-Hodgkin lymphoma, including 321 patients with FL, 46 with marginal zone lymphoma, and 28 with small lymphocytic lymphoma.
The patients were randomized to receive bendamustine alone (control arm) or a combination of bendamustine and obinutuzumab followed by obinutuzumab maintenance (every 2 months for 2 years or until progression).
The primary endpoint of the study was progression-free survival (PFS), as assessed by an independent review committee (IRC). The secondary endpoints were PFS as assessed by investigator review, best overall response, complete response (CR), partial response (PR), duration of response, overall survival, and safety profile.
Among patients with FL, the obinutuzumab regimen improved PFS compared to bendamustine alone, as assessed by IRC (hazard ratio [HR]=0.48, P<0.0001). The median PFS was not reached in patients receiving the obinutuzumab regimen but was 13.8 months in those receiving bendamustine alone.
Investigator-assessed PFS was consistent with IRC-assessed PFS. Investigators said the median PFS with the obinutuzumab regimen was more than double that with bendamustine alone—29.2 months vs 13.7 months (HR=0.48, P<0.0001).
Best overall response for patients receiving the obinutuzumab regimen was 78.7% (15.5% CR, 63.2% PR), compared to 74.7% for those receiving bendamustine alone (18.7% CR, 56% PR), as assessed by the IRC.
The median duration of response was not reached for patients receiving the obinutuzumab regimen and was 11.6 months for those receiving bendamustine alone.
The median overall survival has not yet been reached in either study arm.
The most common grade 3/4 adverse events observed in patients receiving the obinutuzumab regimen were neutropenia (33%), infusion reactions (11%), and thrombocytopenia (10%).
The most common adverse events of any grade were infusion reactions (69%), neutropenia (35%), nausea (54%), fatigue (39%), cough (26%), diarrhea (27%), constipation (19%), fever (18%), thrombocytopenia (15%), vomiting (22%), upper respiratory tract infection (13%), decreased appetite (18%), joint or muscle pain (12%), sinusitis (12%), anemia (12%), general weakness (11%), and urinary tract infection (10%).
About obinutuzumab
Obinutuzumab is being studied in a large clinical program, including the phase 3 GOYA and GALLIUM studies.
In GOYA, researchers are comparing obinutuzumab head-to-head with rituximab plus CHOP chemotherapy in first-line diffuse large B-cell lymphoma. In GALLIUM, researchers are comparing obinutuzumab plus chemotherapy head-to-head with rituximab plus chemotherapy in first-line indolent non-Hodgkin lymphoma.
Additional combination studies investigating obinutuzumab with other approved or investigational medicines, including cancer immunotherapies and small-molecule inhibitors, are planned or underway across a range of blood cancers.
Obinutuzumab was discovered by Roche Glycart AG, a wholly owned, independent research unit of Roche. In the US, obinutuzumab is part of a collaboration between Genentech and Biogen.
Genentech has a patient assistance program, Genentech Access Solutions, that can help qualifying patients access obinutuzumab and other Genentech medications.
The program is designed to help people navigate the access and reimbursement process and provide assistance to eligible patients in the US who are uninsured or cannot afford the out-of-pocket costs for their medicine. For more information, visit www.Genentech-Access.com.
