OBJECTIVES: Since 2017, biosimilars have become available for important anti-cancer biologics. This study aims to investigate the factors associated with biosimilar prescription in Germany, Italy, Spain, France, and the UK.

METHODS: This retrospective cross-sectional study is based on data from IQVIA Oncology Dynamics, a cross-sectional semi-retrospective survey collecting anonymized patient cases from a representative panel of cancer-treating physicians. We analyzed cases with a documented prescription of Bevacizumab, Rituximab, or Trastuzumab between 01.01.2017 and 31.12.2022. A multivariable logistic regression model was fitted with biosimilar product prescription as the dependent variable and age, sex, health insurance status, country, cancer type, cancer stage, line of therapy as impact variables.

RESULTS: A total of 58,915 patients were available for analysis; 16,795 (28.5%) had been treated with biosimilars. The prevalence of biosimilar use increased continuously from 3.5% in 2017 to 55.8% in 2022. Compared to Italy, the odds for biosimilar prescription were highest in the UK (OR: 5.75, 95%CI: 5.28-6.27), followed by Germany (OR: 3.09, 95%CI: 2.41-3.97), France (OR: 1.98, 95%CI: 1.84-2.13), and Spain (OR: 1.62, 95%CI: 1.50-1.75). Furthermore, treatment by gynecologists (OR: 1.86; 95%CI: 1.42-2.42) vs. oncologists, neoadjuvant therapy (OR: 1.73: 95%CI: 1.53-1.95) vs. first-line treatment, age > 80 (OR: 1.34; 95%CI: 1.21-1.48) vs. ≤50, statutory health insurance (SHI, OR: 1.32; 95%CI: 1.19-1.46) vs. private health insurance, gastrointestinal cancers (OR: 4.83, 95%CI: 3.89-6.00), breast cancer (OR: 3.73, 95%CI: 2.94-4.73), female vaginal organ cancers (OR: 3.60, 95%CI: 2.85-4.55), and non-Hodgkin lymphoma (OR: 2,06, 95%CI: 1.11-3.83) vs. lung cancer were significantly associated with a higher odd of biosimilar prescription.

CONCLUSIONS: Our findings highlight parameters of oncological practice associated with a higher probability of a biosimilar prescription (SHI funding, neoadjuvant therapy, treatment by a gynecologist, defined cancer types, higher age) and indicate potential disparities between major European countries in terms of anti-cancer biosimilar utilization.