Calls are growing to expand health insurance coverage for the HER2-positive breast cancer treatment Enhertu (trastuzumab deruxtecan) to include HER2-low breast cancer.

The Health Insurance Review and Assessment Service (HIRA) discussed expanding Enhertu coverage to include HER2-low breast cancer and HER2 (ERBB2) mutation-positive non-small cell lung cancer (NSCLC) at the Cancer Disease Review Committee meeting held in April, but decided “not to set reimbursement criteria.”

However, a petition was recently posted on the National Assembly's Public Petition Board, stating, “Patients with HER2-low metastatic breast cancer are unable to afford the high treatment costs and are giving up on treatment,” requesting the expansion of health insurance coverage for Enhertu. As of Monday morning, the petition had received 7,902 signatures.

“Enhertu is only partially covered by health insurance for HER2-positive patients, leaving low-HER2-expression patients who could benefit from the same treatment unable to afford the high costs and forced to abandon treatment,” the petitioner said.

The petitioner said his mother, who has HER2-low-expressing breast cancer, must pay 5 million won ($3,610) to 700 million won for each injection administered every four weeks. “Since health insurance does not cover the costs, the patient must bear the full burden,” he said. “After calculating how many times we could afford the treatment by adding savings and monthly income, we had to give up.”

Considering clinical results at home and abroad, as well as the necessity of treatment, patients with HER2-low expression should also be included in reimbursement coverage. Institutional reforms reflecting fairness in treatment accessibility and medical realities are necessary, the petitioner emphasized.

“There is still hope. If the expansion of coverage is discussed again and the pharmaceutical company and the government work together, many patients could gain access to treatment,” the petitioner said. “I ask the Health Insurance Review and Assessment Service and the Ministry of Health and Welfare to reconsider the decision to grant health insurance benefits to patients with HER2-low breast cancer.”