Ofatumumab
| Evidence Level: L2 | Predicted Indications: 8 |
Table of Contents
Ofatumumab: From Acute Lymphoblastic Leukemia to Follicular Lymphoma
One-Sentence Summary
Ofatumumab is an anti-CD20 monoclonal antibody, with acute lymphoblastic/lymphocytic leukemia and Richter syndrome as its original indications in the knowledge graph. The TxGNN model predicts it may be effective for Follicular Lymphoma, with 11 clinical trials and 20 publications currently supporting this direction.
Quick Overview
| Item | Content |
|---|---|
| Original Indication | Acute lymphoblastic/lymphocytic leukemia; Richter syndrome (from the knowledge graph; no approved-indication text is available in the US license record) |
| Predicted New Indication | Follicular lymphoma |
| TxGNN Prediction Score | 99.70% |
| Evidence Level | L2 |
| US Market Status | Cancelled only |
| Number of NDAs | 1 (BLA125326) |
| Recommended Decision | Proceed with Guardrails |
Why is This Prediction Reasonable?
Currently, detailed mechanism of action data is not available in the compiled data. Based on known information, ofatumumab is a human anti-CD20 monoclonal antibody. Its efficacy in CD20-positive B-cell malignancies such as chronic lymphocytic leukemia has been established, and mechanistically it may be applicable to follicular lymphoma.
Follicular lymphoma cells express CD20, the antibody’s target. Ofatumumab binds a distinct, membrane-proximal epitope of CD20. It can trigger complement-dependent cytotoxicity and antibody-dependent cellular cytotoxicity, including in rituximab-refractory disease. Several Phase 2 trials, some randomized, and a multicenter monotherapy study in rituximab-refractory follicular lymphoma support this activity.
Important caveats: no Phase 3 trial in follicular lymphoma was identified. The one Phase 3 study listed (NCT01077518, ofatumumab plus bendamustine in rituximab-unresponsive indolent NHL) was terminated and no results were compiled. The US market status is “Cancelled only” for the listed product, which limits practical access.
Clinical Trial Evidence
| Trial Number | Phase | Status | Enrollment | Key Findings |
|---|---|---|---|---|
| NCT00394836 | Phase 2 | Completed | 116 | Single-arm ofatumumab in rituximab-refractory follicular lymphoma |
| NCT01077518 | Phase 3 | Terminated | 346 | Ofatumumab + bendamustine vs bendamustine alone in rituximab-unresponsive indolent B-cell NHL |
| NCT01286272 | Phase 2 | Completed | 135 | Randomized: ofatumumab + bendamustine vs the same plus bortezomib in untreated FL |
| NCT02710643 | Phase 2 | Completed | 110 | MIRO: radiotherapy with or without ofatumumab in stage I/II FL, guided by molecular status |
| NCT00823719 | Phase 2 | Completed | 61 | Ofatumumab + ICE/DHAP salvage chemotherapy before transplant (the summary describes relapsed/refractory DLBCL) |
| NCT00494780 | Phase 2 | Completed | 59 | Two ofatumumab doses + CHOP in previously untreated FL |
| NCT01190449 | Phase 2 | Completed | 51 | CALGB single-agent ofatumumab in previously untreated FL |
| NCT01239394 | Phase 2 | Completed | 43 | Ofatumumab as initial treatment of indolent B-cell lymphoma (mixed histologies) |
| NCT01119794 | Phase 2 | Terminated | 10 | Ofatumumab + bortezomib in relapsed low-grade NHL; limited data |
| NCT00742144 | Phase 1 | Completed | 6 | Safety and PK of ofatumumab in Japanese patients with CD20+ FL or CLL |
Literature Evidence
| PMID | Year | Type | Journal | Key Findings |
|---|---|---|---|---|
| 22389254 | 2012 | Multicenter Phase 2 | Blood | Ofatumumab monotherapy in rituximab-refractory FL (N=116); overall response rate about 10-13% |
| 31174236 | 2019 | Randomized Phase 2 | Cancer | CALGB 50904: ofatumumab + bendamustine with or without bortezomib in untreated high-risk FL |
| 22409295 | 2012 | Phase 2 | Br J Haematol | Ofatumumab (500 or 1000 mg) + CHOP in 59 untreated FL patients |
| 30723894 | 2019 | Phase 2 | Br J Haematol | CALGB 50901: single-agent ofatumumab in untreated low/intermediate-risk FL |
| 38937025 | 2024 | Phase 2 | Lancet Haematol | FIL MIRO: local radiotherapy with MRD-driven anti-CD20 immunotherapy in early-stage FL |
| 18390837 | 2008 | Phase 1/2 | Blood | First clinical use of ofatumumab in relapsed/refractory FL |
| 26043777 | 2015 | Review | Expert Opin Biol Ther | Activity of ofatumumab in CD20+ B-cell lymphomas |
| 29934061 | 2018 | Review | Clin Lymphoma Myeloma Leuk | Evidence review of anti-CD20 regimens in relapsed/refractory CLL, DLBCL and FL |
| 32933335 | 2021 | Review | Expert Opin Biol Ther | Anti-CD20 therapy for B-cell malignancies: status and future directions |
| 35663281 | 2022 | Review | Leuk Res Rep | Immunotherapy in indolent non-Hodgkin lymphoma |
US Market Information
| Authorization Number | Product Name | Dosage Form | Approved Indication |
|---|---|---|---|
| BLA125326 | KESIMPTA (Novartis Pharmaceuticals Corporation) | Injection, solution | Not available; status: cancelled |
Cytotoxicity
| Item | Content |
|---|---|
| Cytotoxicity Classification | Immunotherapy (anti-CD20 monoclonal antibody), not a conventional cytotoxic agent |
| Myelosuppression Risk | Please refer to the package insert warnings and precautions |
| Emetogenicity Classification | Please refer to the package insert warnings and precautions |
| Monitoring Items | Please refer to the package insert; a CBC and liver function are generally reasonable for B-cell-depleting therapy |
| Handling Protection | Please refer to the package insert warnings and precautions |
Safety Considerations
- Drug Interactions: The interaction screen returned 80 interacting drugs, mostly Major or Moderate in severity. Representative Major interactions include deferiprone, samarium (153Sm) lexidronam, adalimumab, baricitinib, certolizumab pegol, cladribine and clozapine. Moderate interactions include alemtuzumab, azathioprine, anakinra, zidovudine and several vaccines (e.g., tetanus toxoid, anthrax, live cholera). Many of these involve additive immunosuppression or myelosuppression, or a reduced vaccine response.
Package insert warnings and contraindications were not available in the compiled data. Please refer to the package insert for these.
Conclusion and Next Steps
Decision: Proceed with Guardrails
Rationale: Several completed Phase 2 trials, including randomized ones and a multicenter study in rituximab-refractory disease, show activity of ofatumumab in follicular lymphoma, and the CD20 target is well established. However, no completed Phase 3 trial exists in this setting, single-agent response in rituximab-refractory disease was modest (about 10-13%), and the listed US license is cancelled. The drug is also already established in CLL/SLL, which is effectively its on-label use. The other predictions are weaker: CLL/SLL subtypes and the susceptibility entity have no subtype-specific data, and metastatic neoplasm rests on a single 10-patient melanoma pilot. Malignant spiradenoma and Langerhans cell histiocytosis lack a biological rationale and appear to be model artifacts.
To proceed, the following is needed:
- FDA package insert warnings and contraindications (a blocking data gap for safety screening)
- Mechanism of action data from DrugBank
- A review of the terminated Phase 3 trial NCT01077518 and any available results
- Clarification of access: a currently marketed US product and formulation for an oncology indication (the listed KESIMPTA license is cancelled)
- A comparison against current standard follicular lymphoma regimens (e.g., rituximab- or obinutuzumab-based)
- A safety monitoring plan, including infection and hepatitis B screening, and an interaction-management plan for concurrent immunosuppressants
Disclaimer
This content is for research purposes only and does not constitute medical advice. Clinical validation is required before any clinical application.