The US Food and Drug Administration (FDA) is reviewing a supplemental New Drug Application (sNDA) for the drug Imbruvica (ibrutinib) in combination with rituximab (Rituxan) for treating Waldenström macroglobulinemia. The sNDA application has been accepted for Priority Review. The full article can be found here, at AbbVie Pressroom.
About the Application
A supplemental New Drug Application is used when an organisation wants to change the indication, label, dosage, or similar for a drug that has previously had a New Drug Application accepted. This is the case for Imbruvica, which has been accepted for the FDA for the treatment of multiple types of cancer, and graft-vs-host disease. However, it hasn’t yet been approved as a combination therapy with rituximab for treating Waldenström macroglobulinemia.
The application for this approval is under Priority Review. This means that the FDA will respond to the application more quickly (within six months rather than ten). This is used for drugs that, if approved, are likely to lead to a significant improvement for patients. More precise information about Priority Review is available at the FDA’s website.
About Waldenström Macroglobulinemia
Waldenström macroglobulinemia (WM) is part of a group of cancers called non-Hodgkin lymphomas. WM forms when lymphoplasmacytic (LPL) cells are overproduced in an abnormal form. LPL cells are a type of white blood cell, and their out-of-control growth leads to build-ups of the cells in areas of the body, particularly the bone marrow, lymph nodes, and spleen, amongst other possible organs. This can cause a protein called Igm to be produced, which then thickens the blood. This cancer is generally slow growing, and may not cause obvious symptoms.
How Imbruvica Works
Imbruvica (ibrutinib) is a medicine that is being investigated as a possible combination treatment with rituximab for WM. It is currently approved to treat several forms of lymphoma (including WM), lymphocytic leukaemia, and graft-versus-host-disease. Imbruvica works by blocking a protein called BTK, which is involved in the B-cell receptor-signalling complex. B cells are a type of white blood cell that can multiply and spread to cause disease, so blocking the BTK protein is thought to reduce this process. The drug has already been granted Breakthrough Therapy Designation by the FDA four times.
The iNNOVATE Study
The supplemental New Drug Application to the FDA for Imbruvica as a combination treatment with rituximab is based on clinical studies of the combination therapy. A recent Phase 3 iNNOVATE study has shown promising results. Data from this trial showed that a combination therapy of Imbruvica and rituximab led to greater progression-free survival rates than rituximab alone. All 150 patients on the trial had untreated and relapsed or refractory WM.
Imbruvica is currently being studied in over 130 clinical trials to better understand what conditions it could be effective as a treatment for.
