Background and supplementary materials

As mentioned in the Aims Section, this Cyclib-tool web is based in our manuscript “Palbociclib and ribociclib in breast cancer: consensus workshop on the management of concomitant medication”1 but 1) with some refinements in the Tables showing specific drug-drug-interactions (DDI), and 2) with the addition of DDIs for abemaciclib. Therefore, we strongly recommend the Cyclib-tool user to ground his or her concomitant drug election on this new information, rather than on the tables published in the manuscript.

However, our manuscript (to see, click here), also contained an Educational Module which we believe that may be complementary and useful for the professionals prescribing CDK4/6i. This Educational module includes:

  1. An overview about metabolism (Section “Drug metabolic pathways and membrane transporters: how to interpret DDIs with palbociclib and ribociclib?”) and particular toxicities of palbociclib and ribociclib.
  2. A section entitled “QTc for oncologists: how to evaluate and manage it”, which may be very informative for non-cardiologist ofessionals to understand its measurement and meaning. As also mentioned in the Aims section of this web, we now consider that the recommendations made in this section regarding palbociclib appear to be excessively conservative based on new information published2.
  3. A formative section that addresses the use of antidepressants in breast cancer, their categorization and their DDI with CDK4/6i, mainly via QTc enlargement (Section “Psychotropic drugs in the breast-cancer population: management of antidepressants in patients under CDK4/6i treatments").

Additionally, this website contains an overview about metabolism (Annex 1, to see click here) and incidence and management of abemaciclib toxicity (Annex 2, to see click here). This information is included in two separate documents as our original article was focused only on palbociclib and ribociclib (the 2 CDK4/6i approved in Spain at the time). We also provide a link to the Summary of Product Characterisitics of palbociclib (Click here), ribociclib (Click here) and abemaciclib (Click here).

Along with the Cyclib-tool web itself, we hope that this additional material can help Oncologists and other Health Care Professionals (Primary Care Physicians, Physicians for many other specialties, Nurses, Pharmacy specialists, etc.) in their daily commitment of managing and taking care of cancer patients.


  1. Bellet M, Ahmad F, Villanueva R, Valdivia C, Palomino-Doza J, Ruiz A, Gonzàlez X, Adrover E, Azaro A, Valls-Margarit M, Parra JL, Aguilar J, Vidal M, Martín A, Gavilá J, Escrivá-de-Romaní S, Perelló A, Hernando C, Lahuerta A, Zamora P, Reyes V, Alcalde M, Masanas H, Céliz P, Ruíz I, Gil M, Seguí MÀ, de la Peña L. Palbociclib and ribociclib in breast cancer: consensus workshop on the management of concomitant medication. Ther Adv Med Oncol. 2019 May 10;11:1758835919833867. doi: 10.1177/1758835919833867. PMID: 31205497; PMCID: PMC6535716.
  2. Santoni M, Occhipinti G, Romagnoli E, Miccini F, Scoccia L, Giulietti M, Principato G, Saladino T, Piva F, Battelli N. Different Cardiotoxicity of Palbociclib and Ribociclib in Breast Cancer: Gene Expression and Pharmacological Data Analyses, Biological Basis, and Therapeutic Implications. BioDrugs. 2019 Dec;33(6):613-620. doi: 10.1007/s40259-019-00382-1. PMID: 31529317