Abstract 245P
Background
CDK4/6 inhibitors are standard of care at 1st and 2nd line for hormone receptor positive (HR+), human epidermal growth factor 2 negative (HER2-) advanced/metastatic breast cancer (ABC/MBC). Abemaciclib (ABE) was first authorized and available in 2018 via patient access schemes before approval for routine use by the National Institute for Health and Care Excellence (NICE). This study aims to assess treatment patterns and clinical benefit of ABE in a real-world setting.
Methods
A multicenter retrospective observational chart review was undertaken of women in the United Kingdom (UK) with HR+, HER2- ABC/MBC treated with ABE-containing regimens during 07/2021 to 05/2022 and with 3 months’ follow-up data post-ABE initiation, including those who may have received ABE via a commercial free access scheme. Descriptive statistics were used to summarize treatment, and outcomes (tumor response and progression free survival; PFS). Kaplan-Meier methods were used to estimate PFS with 95% confidence intervals (CIs).
Results
174 adult women from 9 institutions across the UK were included. Median patient age at ABE initiation was 65.2 years. The majority (90%) had an ABE starting dose of 150mg twice daily. ABE was 1st, 2nd, 3rd, 4th, or 5th+ line treatment for 45.4%, 26.4%, 12.6%, 6.9% and 8.6% of patients, respectively. Hormone therapies given in combination with ABE were fulvestrant (81%) and aromatase inhibitors (AIs; letrozole or anastrozole [19%]). Best tumor response (136 patients); 0.7% had complete response, 27.9% had partial response, 59.6% had stable disease and 11.8% had disease progressed. Median PFS was 21.9 months across all patients (95% CI 19.4 months–not reached), with 1-year PFS rate of 81.1% (1st line), 68.2% (2nd line) and 58.2% (3rd line).
Conclusions
ABE, used in different treatment lines (including later lines in more heavily pretreated patients (≥3rd line)) in combination with fulvestrant or AIs, was associated with a median PFS of 21.9 months in a UK real-world setting. These data are comparable to those from clinical trials supporting the benefit of ABE in patients with HR+, HER2- ABC/MBC.
Clinical trial identification
IRAS Project ID: 292980.
Protocol Number: 2019-8661.
REC Reference: 21/YH/0061.
CPMS ID 47932 HRA approval granted on 11 March 2021.
Legal entity responsible for the study
Eli Lilly and Company Ltd. Indianapolis, IN, USA.
Funding
Eli Lilly and Company Ltd.
Disclosure
J.W. King: Non-Financial Interests, Personal, Advisory Board: Roche, Eli Lilly and Company, Novartis, Bristol Myers Squibb, Exact Science, Prosigna, Gilead, Eisai, AstraZeneca, Seagen; Non-Financial Interests, Personal, Invited Speaker: Roche, Eli Lilly and Company, Novartis, Bristol Myers Squibb, Prosigna, AstraZeneca, Seagen. W. Fakhouri: Non-Financial Interests, Institutional, Full or part-time Employment, Employee and shareholder of Eli Lilly and Company: Eli Lilly and Company; Financial Interests, Personal and Institutional, Stocks/Shares, Employee and shareholder of Eli Lilly and Company: Eli Lilly and Company. R.S. Jarvis: Non-Financial Interests, Institutional, Full or part-time Employment, Employee and shareholder of Eli Lilly and Company: Eli Lilly and Company; Financial Interests, Personal and Institutional, Stocks/Shares, Employee and shareholder of Eli Lilly and Company: Eli Lilly and Company. W. Badreldin: Non-Financial Interests, Institutional, Full or part-time Employment, Employee and shareholder of Eli Lilly and Company: Eli Lilly and Company; Financial Interests, Personal and Institutional, Stocks/Shares, Employee and shareholder of Eli Lilly and Company: Eli Lilly and Company. G. Harper: Non-Financial Interests, Institutional, Sponsor/Funding, Employed by Adelphi Real World, who received funding from Eli Lilly and Company to complete study: Eli Lilly and Company. L. Bateman: Non-Financial Interests, Institutional, Sponsor/Funding, Employed by Adelphi Real World, who received funding from Eli Lilly and Company to complete study: Eli Lilly and Company. C. Palmieri: Financial Interests, Institutional, Research Grant: Pfizer, Daiichi Sankyo, Seagen, Gilead, Exact Science; Non-Financial Interests, Personal and Institutional, Advisory Board: Pfizer, Roche, Daiichi Sankyo, Seagen, Gilead, Exact Science, Eli Lilly and Company, Novartis; Non-Financial Interests, Personal and Institutional, Other, Support for travel and conferences: Roche, Novartis, Gilead. M. Nathan: Financial Interests, Personal and Institutional, Invited Speaker: Roche, Seagen, AstraZeneca, Eli Lilly and Company; Financial Interests, Personal, Invited Speaker: Novartis, Pfizer; Financial Interests, Institutional, Invited Speaker: Merck Sharp and Dohme.