FDA Grants ‘Breakthrough Therapy’ Designations for Ibrutinib
Investigational oncology agent aimed at B-cell malignancies (Feb. 12)
The FDA has granted breakthrough therapy designations for the investigational oral agent ibrutinib (Janssen) as monotherapy for patients with two B-cell malignancies: in patients with relapsed or refractory mantle-cell lymphoma (MCL) who have received prior therapy, and in patients with Waldenström’s macroglobulinemia (WM).
Enacted as part of the 2012 FDA Safety and Innovation Act, a breakthrough therapy designation is intended to expedite the development and review time for potential new medicines to treat serious or life-threatening diseases or conditions.
The filing for ibrutinib in MCL is expected to be made before the end of 2013, and discussions with the FDA about filing in WM are ongoing.
MCL is an aggressive type of B-cell non-Hodgkin lymphoma that usually occurs in older adults. The disease typically begins in the lymph nodes but can spread to other tissues, such as bone marrow and the liver. Ibrutinib targets the B-cell receptor pathway — an important pathway in malignant B-cell growth and proliferation. Approximately 5,000 new cases of MCL occur in the U.S. each year.
WM is a rare type of lymphoma. The disease begins with a malignant change to B-cells during their maturation so that they continue to reproduce more malignant B-cells, resulting in an overproduction of monoclonal immunoglobulin M (IgM) antibody. WM is a hematologic malignancy for which no established standard of care or approved therapeutic agent exists. Approximately 1,500 people develop WM in the U.S. each year.
Ibrutinib was designed to specifically target and selectively inhibit an enzyme called Bruton’s tyrosine kinase (BTK). BTK is a key regulator of at least three critical B-cell pro-survival mechanisms occurring in parallel: apoptosis, adhesion, and cell migration/homing. Through these multiple actions, BTK helps to direct malignant B-cells to lymphoid tissues, thereby allowing access to a microenvironment necessary for survival.
The effectiveness and safety of ibrutinib, alone or in combination with other treatments, are being studied in several B-cell malignancies, including MCL, WM, chronic lymphocytic leukemia, small lymphocytic lymphoma, diffuse large B-cell lymphoma, follicular lymphoma, and multiple myeloma. To date, five phase III trials have been initiated with ibrutinib, and a total of 27 studies are currently registered on clinicaltrials.gov.
Source: Johnson & Johnson; February 12, 2013.