bims-cyhorp Biomed News
on Cyclin-dependent kinases in hormone receptor positive breast cancer
Issue of 2023‒02‒19
eight papers selected by
Piotr Okupski,



  1. J Med Econ. 2023 Feb 16. 1-14
      Background and AimsCombination of a cyclin-dependent kinase 4 and 6 (CDK4/6) inhibitor and an aromatase inhibitor is the standard of care first-line (1L) treatment of hormone receptor-positive (HR+), human epidermal growth factor receptor 2-negative (HER2-) advanced breast cancer (ABC). Updated clinical data have become available from the MONALEESA-2 and PALOMA-2 trials for ribociclib and palbociclib, respectively. This analysis with updated data assessed the cost-effectiveness of ribociclib versus palbociclib, both in combination with letrozole, in the setting of 1L therapy of postmenopausal women with HR+/HER2- ABC, from a United Kingdom (UK) National Health Service perspective.MethodsA three state (progression-free, progressed disease, and death) partitioned survival model with a 1-month cycle was developed. Clinical data were derived from MONALEESA-2 (NCT01958021) and PALOMA-2 (NCT01740427). Treatment effect was modelled using hazard ratios (HRs) for progression-free survival and overall survival derived through a matched-adjusted indirect comparison. Trial data and published literature were used to derive utility values. Cost inputs included drug acquisition, disease monitoring, subsequent therapies, and adverse events. Costs and outcomes were discounted by 3.5%, over a 40-year lifetime horizon. One-way and probabilistic sensitivity analyses were performed.ResultsRibociclib dominated palbociclib, and was both overall cost saving (-£3,273) and more effective (+1.251 quality-adjusted life years [QALYs]). Ribociclib total drug costs were £17,156 lower than palbociclib. At a £30,000 per QALY willingness-to-pay threshold, the probability of ribociclib being cost-effective was almost 100%. Ribociclib remained cost-effective when varying HRs, utilities, drug cost, and health state costs.ConclusionsRibociclib is both cost-saving and cost-effective compared with palbociclib for the 1L treatment of postmenopausal women with HR+/HER2- ABC in the UK.
    Keywords:  CDK 4/6 inhibitors; HR+/HER2− advanced breast cancer; I; I00; I1; I10; breast cancer; cost-effectiveness; palbociclib; ribociclib
    DOI:  https://doi.org/10.1080/13696998.2023.2182051
  2. JAMA Netw Open. 2023 Feb 01. 6(2): e2256170
      Importance: The number of new cancer medicines that are being approved by regulatory agents is increasing exponentially. Yet little is known about the pace at which these medicines reach eligible patients in daily clinical practice during different phases of the postapproval access pathway.Objective: To describe the entire postapproval access pathway of cyclin-dependent kinase 4/6 (CDK4/6) inhibitors in the Netherlands, from regulatory approval to reimbursement and to investigate the adoption of these medicines in clinical practice among patients with metastatic breast cancer.
    Design, Setting, and Participants: This cohort study reviewed approval and reimbursement decisions of the CDK4/6 inhibitors palbociclib, ribociclib, and abemaciclib and estimated the number of patients with metastatic breast cancer who were eligible for these medicines compared with the actual use in clinical practice. The study used nationwide claims data that were obtained from the Dutch Hospital Data. Claims and early access data for patients with hormone receptor-positive and ERBB2 (formerly HER2)-negative metastatic breast cancer who were treated with CDK4/6 inhibitors from November 1, 2016, to December 31, 2021, were included.
    Main Outcomes and Measures: Description of the postapproval access pathway, monthly number of patients who were treated with CDK4/6 inhibitors in clinical practice, and estimated number of patients who were eligible for treatment. Aggregated claims data were used, and patient characteristics and outcomes data were not collected.
    Results: Three CDK4/6 inhibitors have received European Union-wide regulatory approval for the treatment of HR-positive and ERBB2-negative metastatic breast cancer since November 2016. In the Netherlands, the number of patients who have been treated with these medicines increased to approximately 1847 (based on 1 624 665 claims over the entire study period) from approval to the end of 2021. Reimbursement for these medicines was granted between 9 and 11 months after approval. While awaiting reimbursement decisions, 492 patients received palbociclib, the first approved medicine of this class, via an expanded access program. By the end of the study period, 1616 patients (87%) were treated with palbociclib, whereas 157 patients (7%) received ribociclib, and 74 patients (4%) received abemaciclib. The CKD4/6 inhibitor was combined with an aromatase inhibitor in 708 patients (38%) and with fulvestrant in 1139 patients (62%). The pattern of use over time appeared to be somewhat lower compared with the estimated number of eligible patients (1847 vs 1915 in December 2021), especially in the first 2.5 years after approval.
    Conclusions and Relevance: This study found that CDK4/6 inhibitors rapidly reached many eligible patients with metastatic breast cancer and were adopted gradually over time in the Netherlands. Adoption of innovative medicines may be further optimized, and better transparency of the availability of new medicines during different phases of the postapproval access pathway is needed.
    DOI:  https://doi.org/10.1001/jamanetworkopen.2022.56170
  3. Expert Opin Drug Saf. 2023 Feb 15.
      BACKGROUND: Thrombosis is the second leading cause of mortality in cancer patients. This study aimed to investigate the association between cyclin-dependent kinase 4 and 6 inhibitors (CDK4/6i) and thrombosis.RESEARCH DESIGN AND METHODS: A retrospective pharmacovigilance analysis based on real-world data combined with a systematic review was used to explore the thrombotic risk profiles of CDK4/6i. The study has been registered with Prospero (CRD42021284218).
    RESULT: In the pharmacovigilance analysis, CDK4/6i showed a higher rate of reported venous thromboembolism (VTE) (ROR= 2.78, 95% CI= 2.64-2.92), with the highest signal for trilaciclib (ROR= 27.55, 95% CI= 13.43-56.52) but only 9 cases, followed by abemaciclib (ROR= 3.73, 95% CI= 3.19-4.37). For arterial thromboembolism (ATE), only ribociclib increased the reporting rate (ROR= 2.14, 95% CI= 1.91-2.41). In the meta-analysis, palbociclib, abemaciclib, and trilaciclib all increased the risk of VTE (OR= 2.23, 3.17, and 3.90). In the subgroup analysis, only abemaciclib increased the risk of ATE (OR= 2.11, 95% CI= 1.12-3.99), while ribociclib did not significantly increase the risk of ATE compared with controls (OR= 5.44, 95% CI= 0.95-31.0).
    CONCLUSIONS: CDK4/6i had different profiles of thromboembolism. Palbociclib, abemaciclib, or trilaciclib increased the risk of VTE. Ribociclib and abemaciclib showed a weak association with the risk of ATE.
    Keywords:  FAERS; arterial thromboembolism; cyclin-dependent kinase 4 and 6 inhibitors; pharmacovigilance; systematic review; venous thromboembolism
    DOI:  https://doi.org/10.1080/14740338.2023.2181338
  4. Sci Rep. 2023 Feb 15. 13(1): 2710
      Resistance to therapy remains a major obstacle in cancer management. Although treatment with hormone and CDK4/6 inhibitors is successful in luminal breast cancer, resistance to these treatments is frequent, highlighting the need for novel therapeutic strategies to delay disease progression and improve patient survival. Here, we assessed the mechanisms of acquired resistance using T47D and MCF-7 tamoxifen- and palbociclib-resistant cell-line variants in culture and as xenografts, and patient-derived cells (PDCs) obtained from sensitive or resistant patient-derived xenografts (PDXs). In these models, we analyzed the effect of specific kinase inhibitors on survival, signaling and cellular aggressiveness. Our results revealed that mTOR inhibition is more effective than PI3K inhibition in overcoming resistance, irrespective of PIK3CA mutation status, by decreasing cell proliferation and tumor growth, as well as reducing cell migration and stemness. Moreover, a combination of mTOR and CDK4/6 inhibitors may prevent pathway reactivation downstream of PI3K, interfering with the survival of resistant cells and consequent tumor escape. In conclusion, we highlight the benefits of incorporating mTOR inhibitors into the current therapy in ER + breast cancer. This alternative therapeutic strategy not only enhances the antitumor response but may also delay the emergence of resistance and tumor recurrence.
    DOI:  https://doi.org/10.1038/s41598-023-29425-y
  5. Clin Pharmacokinet. 2023 Feb 17.
      BACKGROUND AND OBJECTIVE: Renal impairment is common in patients with cancer and can alter the PK and thus the safety and efficacy of drugs. We assessed the impact of renal impairment during treatment with ribociclib, a cyclin-dependent kinase 4/6 inhibitor, and determined dose recommendations for patients with advanced breast cancer with renal impairment.METHODS: A comprehensive assessment integrating pharmacokinetic, safety, and efficacy data from a phase I dedicated renal impairment study in non-cancer subjects and six phase I-III trials in patients with cancer was performed.
    RESULTS: Ribociclib showed higher pharmacokinetic exposure in subjects with renal impairment than those with normal renal function following a single 400-mg dose in the dedicated renal impairment study. However, in patient trials, both single-dose and steady‑state ribociclib exposure was comparable between patients with cancer with mild/moderate renal impairment and those with normal renal function following the recommended starting dose of 600 mg. Model-predicted steady‑state exposure in patients with advanced breast cancer was also similar across the renal function groups. Progression-free survival was similar and safety profiles were generally consistent across the renal cohorts (normal/mild/moderate) in patients with advanced breast cancer, with low-grade and manageable adverse events, demonstrating a positive benefit-risk profile.
    CONCLUSIONS: From the collective evidence and considering a real-world clinical setting, no dose adjustment is recommended for patients with mild/moderate renal impairment, whereas a reduced dose is recommended for patients with severe renal impairment. This report presented a holistic and innovative strategy to determine dose in patients with renal impairment and demonstrated the effectiveness of integrating the data of both a clinical pharmacology study and patient trials to justify doses in patients with renal impairment.
    CLINICAL TRIAL REGISTRATION: Clinicaltrials.gov identifiers: NCT02431481, NCT01958021, NCT02422615, NCT02278120, NCT01237236, NCT01898845, NCT01872260.
    DOI:  https://doi.org/10.1007/s40262-022-01206-2
  6. NPJ Precis Oncol. 2023 Feb 16. 7(1): 18
      Endocrine therapy (ET) in combination with CDK4/6 inhibition is routinely used as first-line treatment for HR+/HER2- metastatic breast cancer (MBC) patients. However, 30-40% of patients quickly develop disease progression. In this open-label multicenter clinical trial, we utilized a hypothesis-driven protein/phosphoprotein-based approach to identify predictive markers of response to ET plus CDK4/6 inhibition in pre-treatment tissue biopsies. Pathway-centered signaling profiles were generated from microdissected tumor epithelia and surrounding stroma/immune cells using the reverse phase protein microarray. Phosphorylation levels of the CDK4/6 downstream substrates Rb (S780) and FoxM1 (T600) were higher in patients with progressive disease (PD) compared to responders (p = 0.02). Systemic PI3K/AKT/mTOR activation in tumor epithelia and stroma/immune cells was detected in patients with PD. This activation was not explained by underpinning genomic alterations alone. As the number of FDA-approved targeted compounds increases, functional protein-based signaling analyses may become a critical component of response prediction and treatment selection for MBC patients.
    DOI:  https://doi.org/10.1038/s41698-023-00360-5
  7. Chem Biodivers. 2023 Feb 17. e202200554
      The optimized geometry of palbociclib, (PD 0332991) (8-cyclopentyl-6-ethanoyl-5-methyl-2-(5-(piperazin-1-yl)pyridin-2-ylamino)pyrido[2,3-d]pyrimidin-7(8H)-one), electrostatic potential map, molecular orbitals were calculated using the density functional theory. The geometry was used in a molecular docking study of palbociclib-kinase complexes, results could be explained by the charge of the nitrogen and oxygen atoms within the palbociclib. Energy gap of HOMO-LUMO surfaces, could help to explain the reactivity of the ligand and the hydrogen bonding with three different kinases, two of CDK6 and one of CDK4 type. Docking results are similar and complementary with literature reports using molecular dynamics, were hydrogen bonding was obtained and analyzed. The promiscuity of three kinases with palbociclib was detected by the docking results, thus, palbociclib could be used in other types of cancer besides myeloid leukemia. Some similarities are found with CDK4/CDK6 kinases which allow us to determine that palbociclib could be used to control other resistant inhibitor types of cancer.
    Keywords:  kinases CDK4/CPD6; molecular docking; palbociclib; poly target agent; quantum chemistry
    DOI:  https://doi.org/10.1002/cbdv.202200554
  8. Clin Adv Hematol Oncol. 2023 Feb;21 Suppl 3(2): 12-15