How it is administered

Pirtobrutinib is taken orally as a tablet. The recommended dose is 200 mg once daily, swallowed whole with water, with or without food. Tablets should not be cut, crushed, or chewed. If a dose is missed by more than 12 hours, the next dose should be taken as scheduled, without making up the missed dose.

How it works

Pirtobrutinib is a small molecule, noncovalent inhibitor of Bruton tyrosine kinase (BTK). BTK is a key signaling protein in B-cells, which are a type of white blood cell involved in many blood cancers. BTK signaling is necessary for B-cell proliferation, movement, and survival. By binding to both normal and mutated forms of BTK, pirtobrutinib blocks its activity, leading to reduced growth and survival of malignant B-cells.

This action helps to control cancers such as mantle cell lymphoma (MCL) and chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL/SLL), especially in patients who have already received other treatments. Pirtobrutinib maintains BTK inhibition throughout the dosing interval, which is important for continuous control of cancer cell growth.

Who Should take it

Pirtobrutinib is indicated for adults with certain blood cancers:

• Mantle cell lymphoma (MCL) that has returned or did not respond to at least two previous treatments, including another BTK inhibitor.
• Chronic lymphocytic leukemia (CLL) or small lymphocytic lymphoma (SLL) in adults who have received at least two prior lines of therapy, including a BTK inhibitor and a BCL-2 inhibitor.

These approvals are based on response rates seen in clinical trials, and ongoing studies are confirming its long-term benefits. It is generally used when other standard treatments have not worked or are no longer effective.

Who should not take it

There are no absolute contraindications listed for pirtobrutinib. However, patients who are allergic to any of its components should not take it.

Special caution is needed for patients with severe liver problems, those at risk for serious infections, bleeding, or heart rhythm problems. Women who are pregnant or breastfeeding should not use pirtobrutinib, as it can harm the unborn baby or nursing infant. Always discuss your full medical history with your healthcare provider before starting this medication.

Commonly used with

Pirtobrutinib is often used as a single agent in patients who have already tried other therapies. In some cases, it may be used in combination with other treatments for blood cancers, especially when previous therapies have failed. Your healthcare team will decide the best combination based on your specific situation.

Commonly tested with

In clinical trials, pirtobrutinib has been studied primarily as a single agent in patients with relapsed or refractory mantle cell lymphoma and chronic lymphocytic leukemia/small lymphocytic lymphoma. It is often tested in patients who have previously received other BTK inhibitors and BCL-2 inhibitors. Ongoing studies may explore its use in combination with other cancer therapies.