430P - Real-world patient characteristics and treatment patterns in HR+/HER2+ metastatic breast cancer patients in 5 European countries

Background

For patients (pts) with HR+/HER2+ metastatic breast cancer (mBC) with no contraindication for chemotherapy (CT), the ESMO mBC Living guidelines recommend first-line CT in combination with dual anti-HER2, followed by endocrine therapy (ET) with dual anti-HER2 agents upon CT completion as maintenance therapy. This study assesses patient characteristics and treatments patterns for adults with HR+/HER2+ mBC in 5 European countries.

Methods

Data were collected using the Adelphi Advanced BC Disease Specific Programme. Oncologists in France, Germany, Italy, Spain, and the UK abstracted data from patient medical records. This study included pts who had previously received induction therapy and were receiving maintenance treatment for HR+/HER2+ mBC at time of data abstraction (July 2022 to February 2023).

Results

495 pts with HR+/HER2+ mBC were included. At time of data abstraction: mean (SD) age was 62 (9.88) years; 81% had de novo mBC; 63% had visceral metastases; pain was the most common symptom (22%). Among pts who received early-stage BC treatment (n=78), 63% received CT and ≥1 anti-HER2 agent. 89% of pts received CT and a single/dual anti-HER2 agent(s) as 1L regimen for mBC, with 81% of pts then receiving ET and a single/dual anti-HER2 agent(s) as a maintenance regimen (Table). CT only was received by 6% of the sample as an induction regimen, with 70% then receiving ET and a single/dual anti-HER2 agent(s) as a maintenance regimen. The remaining 4% of pts received a single/dual anti-HER2 agent(s) as an induction regimen, with single anti-HER2 +/- ET the most common maintenance regimens. Table: 430P

Treatment sequencing in pts with HR+/HER2+ mBC

* Includes dual anti-HER2 and ET + 3 anti-HER2 regimens

Conclusions

Most pts were de novo mBC, with two thirds of the population having visceral metastases. While most pts in our study received treatment aligned with ESMO guidelines, some regimens did not align to the guidelines. Further investigation is required to understand the factors that drive treatment decisions and adherence to the guidelines.

Clinical trial identification

Editorial acknowledgement

Legal entity responsible for the study

Adelphi Real World.

Funding

This study, utilizing Adelphi Real World’s ABC DSP, was sponsored by Pfizer Inc.

Disclosure

C. Criscitiello: Financial Interests, Personal, Invited Speaker: Pfizer, Novartis, Eli-Lilly, Roche, Gilead; Financial Interests, Personal, Advisory Board: MSD, Seagen, AstraZeneca, Daiichi Sankyo. K. Lewis, A. Lambert, G. Thomason: Financial Interests, Institutional, Full or part-time Employment: Adelphi Real World. E. Broughton: Financial Interests, Personal, Full or part-time Employment: Pfizer; Financial Interests, Personal, Stocks/Shares: Pfizer.