Pirtobrutinib (Jaypirca, Eli Lilly) is a non-covalent, third-generation BTK inhibitor. 

When is Pirtobrutinib Used?

Pirtobrutinib is indicated for the treatment of relapsed or refractory patients with chronic lymphocytic leukemia (CLL) who have previously failed or relapsed two other treatments.

How is Pirtobrutinib Administered?

This medication is taken orally at a recommended dosage of two 100 mg tablets a day. 

How Does Pirtobrutinib Work?

Pirtobrutinib is a non-covalent Bruton's tyrosine kinase (BTK) inhibitor, which means it binds to BTK in a reversible manner. This contrasts with covalent BTK inhibitors that form a permanent bond with BTK.

In CLL patients who have developed resistance to covalent BTK inhibitors (like ibrutinib, acalabrutinib, or zanubrutinib) due to BTK mutations, pirtobrutinib's reversible binding allows it to maintain efficacy. This is because pirtobrutinib can still inhibit BTK even if certain mutations have altered the protein structure, whereas covalent inhibitors might lose effectiveness. Over time, additional mutations in the CLL cell may occur, which can cause pirtobrutinib to stop working. 

How Effective is Pirtobrutinib for CLL?

A 2023 study of pirtobrutinib in CLL showed the following data: 

• Patients who have previously taken a covalent BTK inhibitor can expect pirtobrutinib to limit the progression of CLL for an average of 1.6 years.
• If you have not taken venetoclax or other BCL-2 inhibitors, you can expect pirtobrutinib to limit the progression of CLL for an average of 1.9 years. 
• If you have previously taken venetoclax, you can expect pirtobrutinib to limit the progression of CLL for an average of 1.3 years. 

Side Effect Profile of Pirtobrutinib

The percentage of CLL patients who experience mild-moderate versions of common side effects from pirtobrutinib is shown below. 

You can visit the Side Effects Management section of this guide for more information on these side effects. 

For more information on this therapy, check out Jaypirca Prescribing Information.

Financial Resources for Pirtobrutinib

To locate financial resources for pirtobrutinib, click here to visit the financial support section of the guide.