Cost-Effectiveness of Treatment Options for HER2-Positive Breast Cancer

The most cost-effective treatment strategy for women with HER2-positive stage II to III breast cancer in a simulated clinical practice cohort was neoadjuvant trastuzumab + paclitaxel + pertuzumab followed by adjuvant trastuzumab for patients with pathologic complete response and by adjuvant dose-dense anthracycline/cyclophosphamide and T-DM1 for those with residual disease. Researchers presented findings from their analysis of five treatment strategies during a session at the San Antonio Breast Cancer Symposium in San Antonio, Texas. 

“Several neoadjuvant and adjuvant treatment options exist for patients with HER2-positive stage II to III breast cancer. Recent results of the KATHERINE trial showed that adjuvant T-DM1 can reduce distant recurrence risk in patients without pathologic complete response (pCR) after neoadjuvant chemotherapy,” researchers explained in a session abstract. “However, pCR rates can range between 20% and 80% depending on treatment regimen and subtype. Given the high cost of T-DM1 and other HER2-targeted agents, understanding the relationship between the costs and health consequences of various neoadjuvant-adjuvant treatment combinations is needed.”

Researchers developed a model to analyze the cost-effectiveness of  five strategies: 

1. neoadjuvant dose-dense anthracycline/cyclophosphamide (ddAC) followed by paclitaxel (T), trastuzumab (H), and pertuzumab (P) (ddAC/THP) + adjuvant H for residual disease and for pCR;
2. neoadjuvant ddAC/THP + adjuvant T-DM1 for residual disease and adjuvant H for pCR;
3. neoadjuvant THP + adjuvant ddAC followed by T-DM1 for residual disease and adjuvant H for pCR;
4. neoadjuvant HP + adjuvant ddAC/THP followed by T-DM1 for residual disease and adjuvant H for pCR; and
5. neoadjuvant docetaxel, carboplatin, H, and P + adjuvant-T-DM1 for residual disease and adjuvant H for pCR. 

Strategy 3 was the dominating strategy, researchers reported, with an estimated average 10.56 gain in quality-adjusted life years and $274,550 in costs per patient. 

In addition, “probabilistic sensitivity analysis indicated Strategy 3 to have the highest probability of cost-effectiveness and expected net benefit across a wide range of willingness-to-pay thresholds ($0-250,000),” researchers added. “These findings persisted when changing a number of assumptions, including increasing starting age and varying pCR rates and distant recurrence probability after an initial local recurrence.” 

—Jolynn Tumolo

Reference

Kunst NR, Wang SY, Hood A, et al. Cost-effectiveness of different neoadjuvant followed by adjuvant treatment combination strategies for women with HER2-positive breast cancer. December 13, 2019.