Inavolisib-Based Therapy for PIK3CA-Mutated Advanced Male Breast Cancer: A Cost-Effectiveness Analysis

The Phase III INAVO120 trial established inavolisib-based therapy as a superior first-line treatment for PIK3CA-mutated, HR-positive, HER2-negative advanced breast cancer, a finding of particular importance for the historically underrepresented male population with high unmet need.

A lifetime Markov model was developed from a US payer perspective to evaluate the cost-effectiveness of inavolisib plus palbociclib and fulvestrant versus placebo plus palbociclib and fulvestrant in men with PIK3CA-mutated advanced breast cancer. Primary outcomes were life-years (LYs), quality-adjusted life-years (QALYs), and the incremental cost-effectiveness ratio (ICER).

The inavolisib group provided an additional 1.23 LYs and 0.69 QALYs compared to the placebo group, resulting in an ICER of $886,440 per QALY. One-way sensitivity analysis identified the price of inavolisib as the primary driver of the ICER. Probabilistic sensitivity analysis showed a 0% probability of inavolisib being cost-effective at a willingness-to-pay threshold of $150,000 per QALY.

Inavolisib-based therapy is not cost-effective for treating PIK3CA-mutated advanced male breast cancer at its current price. Significant price reductions or adjustments to value assessment frameworks are required to ensure equitable access for this underserved population.