You will have seen mention of CDK inhibitors in various articles in this edition of The Beacon.
A number of clinical trials have shown encouraging results for the CDK inhibitors palbociclib (Ibrance) and ribociclib (Kisqali) as a ‘first-line’ treatment for postmenopausal women with hormone receptor positive, HER2-negative metastatic breast cancer.
Results have shown that, taken with an aromatase inhibitor (anastrozole or letrozole), they substantially increase the length of time before the cancer progresses when compared with the current standard treatment of an aromatase inhibitor on its own.
A third CDK inhibitor, abemaciclib, has been tested with very good results as a later-line treatment (after other treatments have been tried), when taken with fulvestrant (Faslodex). Abemaciclib is not yet available to buy in Australia.
A number of other trials have further explored how these drugs can best be used to treat metastatic breast cancer.
This includes a trial with pre- and peri-menopausal women, where ribociclib was added to goserelin and tamoxifen, or an aromatase inhibitor. It was found to extend progression-free survival to 23.8 months, compared with 13.0 months for women treated with a placebo, goserelin and tamoxifen or an aromatase inhibitor.
The PATINA trial is investigating adding palbociclib to hormone therapy and anti-HER2 therapy for people with hormone receptor positive, HER2-positive metastatic breast cancer.
Trials are also exploring how these drugs may be used in treatment of high-risk early breast cancer, the monarchE trial is investigating whether adding abemaciclib to hormone therapy is better than hormone therapy alone for women with high-risk early breast cancers.
The PATINA and monarchE trials are currently recruiting in Australia, so talk to your medical oncologist if you think they might be of interest to you.