Long-term observational study of treatment with the drug ibrutinib (PCI-32765) in patients with certain types of blood and lymphatic cancers

Ibrutinib is a medication used to treat certain types of blood and lymphatic cancers. It belongs to the group of tyrosine kinase inhibitors, specifically the Bruton’s tyrosine kinase (BTK) inhibitors, and inhibits the spread of malignant B cells. B cells are specialized cells of the immune system; in certain cancers, they become malignant—they grow uncontrollably, no longer perform their defensive function, and displace healthy cells in the blood and bone marrow. Ibrutinib works by blocking an enzyme called Bruton’s tyrosine kinase, thereby shutting down a key signaling pathway in cancer cells that is essential for their survival and proliferation. As a result, the cancer cells die or their growth is slowed. This is a targeted therapy taken daily as a tablet and is often used long-term. The standard treatment for these diseases depends on the exact diagnosis and may consist of chemotherapy, antibodies, or other targeted medications. Ibrutinib has established itself as an effective long-term therapy.

The CAN3001 study is a so-called “long-term extension study.” This means it is exclusively for patients who have already participated in another ibrutinib study. They will continue to receive the medication at the same dosage—as long as their treating physician sees a benefit and no serious side effects occur. The goal of the study is not to test a new treatment, but to collect long-term data on the safety and efficacy of ibrutinib while maintaining access to the drug for those affected. The dose of ibrutinib that patients are already receiving will remain unchanged. As part of the NCT01804686 study, ibrutinib will be taken for as long as patients derive clinical benefit from it and no serious side effects occur.

Eligible participants include women and men aged 18 and older with certain forms of blood and lymphatic cancers, including chronic lymphocytic leukemia (CLL), various non-Hodgkin lymphomas (such as mantle cell, follicularor diffuse large B-cell lymphoma), as well as patients with Waldenström’s macroglobulinemia or chronic rejection following a stem cell transplant, known as chronic graft-versus-host disease. To be eligible for this study, patients must currently be participating in an ibrutinib study that has already been completed and must have been receiving ibrutinib for at least 6 months. Alternatively, individuals who originally received a different medication in a comparative study and have since been switched to ibrutinib may also participate—in this case, the 6-month rule does not apply, although more frequent medical checkups are required. Patients from a specific combination therapy trial involving ibrutinib and nivolumab may also participate if they are currently still taking these medications. Patients who are taking certain blood-thinning medications (e.g., Marcumar) or medications that could strongly interact with ibrutinib (so-called CYP3A4 or CYP3A5 inhibitors) are excluded.