Global representativeness and impact of funding sources in cost-effectiveness research on systemic therapies for advanced breast cancer: A systematic review

Background

Breast cancer (BC) is the most incident tumor and, consequently, any new intervention can potentially promote a considerable budget impact if incorporated. Cost-effectiveness (CE) studies assist in the decision-making process but may be influenced by the country's perspective of analysis and pharmaceutical industry funding.

Methods

A systematic review of Medline, Scopus, and Web of Science from January 1st, 2012 to July 8th, 2022 was conducted to identify CE studies of tumor-targeted systemic-therapies for advanced BC. Articles without incremental cost-effectiveness ratio calculations were excluded. We extracted information on the country and class of drug studied, comparator type, authors’ conflicts of interest (COI), pharmaceutical industry funding, and authors' conclusions.

Results

71 studies comprising 204 CE assessments were included. The majority of studies were from the United States and Canada (44%), Asia (32%) and Europe (20%). Only 8% were from Latin America and none from Africa. 31% had pharmaceutical industry funding. The most studied drug classes were cyclin-dependent-kinase inhibitors (29%), anti-HER2 therapy (23%), anti-PD(L)1 (11%) and hormone therapy (11%). Overall, 34% of CE assessments had favorable conclusions. Pharmaceutical industry-funded articles had a higher proportion of at least one favorable conclusion (82% vs. 24%, p-value<0.001), European countries analyzed (45% vs. 9%, p-value = 0.003), and CE assessments with same class drug comparators (56% vs. 33%, p-value = 0.004).

Conclusions

Breast cancer CE literature scarcely represents low-and-middle-income countries' perspectives and is influenced by pharmaceutical industry funding which targets European countries', frequently utilizes comparisons within same-drug class, and is more likely to have favorable conclusions.