The BTK (Bruton’s Tyrosine Kinase) inhibitor, ibrutinib, revolutionized the care of chronic lymphocytic leukemia by blocking the B cell receptor (BCR) pathway and thus preventing the cancerous cells from getting positive survival messages. This inhibition leads to cell death and control of the CLL.
Acalabrutinib was the next BTK inhibitor approved and has helped many patients stay on a BTK inhibitor when ibrutinib had intolerable side effects.
Now zanubrutinib has taken a step closer to being a third BTK treatment option.
The well respected NCCN (National Comprehensive Cancer Network) publishes treatment guidelines for many cancers including CLL and in Dec. 2020 made the following updates to their CLL recommendations:
- First-line therapy of zanubrutinib as a single agent is recommended for the treatment of CLL / SLL with del(17p) and TP53 mutations in patients with contraindication to other bruton tyrosine kinase (BTK) inhibitors who have indications for treatment.
- For second-line treatment and subsequent therapy, the NCCN recommends the indication as a single agent for the treatment of CLL / SLL with or without del(17p) and TP53 mutations in patients with intolerance or contraindication to other BTK inhibitors who have indications for retreatment.
This is important for two reasons.
- First is that if your doctor believes zanubrutinib is the best medication for you, with it being part of the NCCN guidelines, odds are good your insurance will pay for it. It is already approved for a closely related blood cancer, mantle cell lymphoma (MCL), so its use in CLL would be “off label.”
- The second is that being added to the NCCN guidelines often presages FDA approval for similar indications. It did for both ibrutinib and acalabrutinib.
The reasons for this NCCN recommendation are based on its safety and efficacy data and on its ability to be used with many commonly used other drugs without fear of significant drug/drug interactions.
Over the next few months, CLL Society will be reporting on the promising research on zanabrutinib from ASH 2020 and elsewhere that likely informed the NCCN panel of experts in the making of their recommendations.
Blocking the B cell receptor through the BTK pathway is a very safe and effective way to control CLL so having another possible option for patients is good news for CLL patients.
Here’s a link to the news online.
Stay strong. We are all in this together.
Brian Koffman MDCM (retired) MS Ed
Co-Founder, Executive VP and Chief Medical Officer
CLL Society, Inc.