Question: Hello Doctor,
Thank you in advance for your help. I am looking at two drugs which treat the indication Chronic Lymphocytic leukaemia:

Imbruvica (ibrutinib)

rituximab biosimilar (APB-798)
1. Assume rituximab biosimilar (APB-798) is FDA approved for Chronic Lymphocytic leukaemia. In your view as a specialist, would a doctor consider it to be a substitute and a competitor to Imbruvica (ibrutinib) for purposes of treating patients? I note that the two drugs treat the same indication but have different mechanisms of action.
2. Why or why not?
See below the research that we have already done (so it is not necessary to give me any background on the drugs):
3. Am I missing anything here?
Approved Name
(Alternate names)
Rituximab biosimilar (APB-798)
Stage
Phase III
Sales ($m)

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Indication
Chronic lymphocytic leukaemia, Non-Hodgkin’s lymphoma
Mechanism of Action T-lymphocyte stimulants
Companies Involved
Amgen (US): Originator
Allergan (US): Licensee
Description
A biosimilar of rituximab, a monoclonal antibody which targets CD20, is being developed by Allergan in collaboration with Amgen, for the treatment of cancer and rheumatoid arthritis. Development is underway for chronic lymphocytic leukaemia.
Phase III development is ongoing for rheumatoid arthritis and non-Hodgkin's lymphoma in the EU.
Launch, Geographic Details
Phase III in Spain, Germany, Italy, Poland, Estonia.
In Jan-19, Amgen announced positive results from a Phase III trial that met its primary endpoint in patients with moderate to severe rheumatoid arthritis. Investigation is underway for chronic lymphocytic leukaemia (Amgen pipeline, Feb-17).
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Approved Name
(Alternate names)
Ibrutinib
(Imbruvica, PCI-32765, JNJ-0000, CRA-032765)
Stage
Preregistered in EU, Registered in Japan
Sales ($m)
$5.3bn (‘20E)

Indication
Chronic lymphocytic leukaemia, Non-Hodgkin’s lymphoma, Mantle-cell lymphoma
Mechanism of Action
Kinase-EMT-protein-inhibitors, ITK-protein-inhibitors
Companies Involved
Celera Genomics (US): Originators
Janssen Biotech (US): Licensee
Description
Ibrutinib is a selective Bruton's tyrosine kinase (Btk) inhibitor, jointly developed by AbbVie (Pharmacyclics) and J&J (Janssen Biotech), for treatment of various haematological malignancies, solid tumours, and graft-versus-host disease. Ibrutinib acts by blocking B-cell antigen receptor signalling, thereby inducing cell death. As Btk is not found in T-cells, ibrutinib does not affect T-cell receptor signalling. The product is available for chronic lymphocytic leukaemia, graft-versus-host disease, mantle-cell lymphoma, marginal zone B-cell lymphoma and Waldenstrom's macroglobulinaemia.
Launch, Geographic Details
Approved for chronic lymphocytic leukaemia, mantle-cell lymphoma and Waldenstrom's macroglobulinaemia in Europe, the US, Australia, Canada, Brazil, Chile, China, XXXXXXX Uruguay, Argentina and Puerto Rico.
In clinical development for diffuse large B cell lymphoma, follicular lymphoma, squamous-cell cancer, non-Hodgkin's lymphoma, pancreatic cancer, acute myeloid leukaemia, B-cell lymphoma, marginal zone B-cell lymphoma, multiple myeloma, solid tumours and gastrointestinal cancer, among many others.
Registered in Japan, Preregistration completed for EU. In January 2019, US FDA approved Imbruvica (ibrutinib) in combination with obinutuzumab in previously untreated adult patients with chronic lymphocytic leukaemia or small lymphocytic lymphoma (CLL/SLL). In November 2018, Janssen submitted a Type II variation to the EMA to expand the use of ibrutinib in combination with obinutuzumab. Positive results from a Phase III trial supported the submission.
Patent Details
In October 2016, Janssen was granted a US patent, expected to expire in 2027. Pharmacyclics has been granted composition of matter patents covering ibrutinib and related BTK inhibitor compounds and expects to receive patent protection up to at least December 2026 in the US and other countries.

I have asked this question 5 DAYS ago, not 16 hours ago. Please have some answer this immediately since I have stressed its urgency multiple times.