Hormone receptor (HR) positive, human epidermal growth factor receptor 2 (HER2) negative metastatic breast cancers have had a high unmet medical need even though it accounted for 59.3 percent of all breast cancer as of 2015.

Professor Lee Geun-seok, head of the breast cancer center at the National Cancer Center, stresses the importance of Verzenio receiving reimbursement, during a news conference at the Westin Chosun Seoul on Tuesday.

There has been no long-term improvement in treatment methods in this area despite a large number of patients. Therefore, patients with HR+/HER2- advanced or metastatic breast cancer have needed long-term anticancer chemotherapy amid continued recurrence and often had to suffer from cumulative toxicity and side effects.

However, the releases of CDK 4/6 inhibitor – Pfizer's Ibrance, Lilly's Verzenio, and Novartis' Kisqali – in Korea have entirely changed the treatment environment. These new drugs have proven unprecedented effectiveness as a first-line treatment with letrozole and as a second-line treatment with fulvestrant.

Pfizer had gained health insurance benefits in 2017 for the combo with letrozole as the first-line endocrine therapy in postmenopausal patients with HR+/HER2- advanced and metastatic breast cancer.

However, there have been mounting calls among patients and physicians for a more comprehensive insurance benefit amid the increase of younger patients who had to pay the full medical bill because they were premenopausal while the drugs showed a progression-free survival time of more than twice that of the conventional monotherapy in a group of HR+/HER2- patients, who have failed their first hormone therapy when used with fulvestrant.

Despite such high unmet medical needs, the drug has long been out of reach for patients because the drugs were not entitled to reimbursement as fulvestrant was not reimbursable.

However, the government decided to reimburse fulvestrant in April last year, leading to the reimbursement for Pfizer's Ibrance and Lilly's Verzenio from Monday.

Notably, the reimbursement for Verzenio has drawn significant attention as it is the only domestically approved CDK 4/6 inhibitor that can be taken daily without a resting period and not requiring the patient to eat meals before taking it.

Professor Lee Geun-seok, head of the Breast Cancer Center at the National Cancer Center, explained the importance of the drug receiving reimbursement, during a news conference held by Lilly Korea on Tuesday.

"In metastatic breast cancer, it is essential to introduce therapy to increase the survival rate while maintaining the patient's quality of life," Professor Lee said. "The fact that a treatment that has proven to prolong the survival time while clinically maintaining a quality of life, such as Verzenio, received reimbursement comes as a gift to patients as it can increase their access to the treatment and reduce the burden of medical expenses."

Lee stressed that the period was significantly extended before patients had to start chemotherapy, which means that patients could not only expect a prolonged survival period but also maintain their quality of life.

"Notably, the drug showed improved progression-free survival in patients with rapid disease progression and patients with high tumor grade," Lee said. "Also, when compared with the study results of other drugs among the same series of CDK 4/6 inhibitors, Verzenio showed a relatively low frequency of severe neutropenia and had a differentiated mechanism of inhibiting CDK4 14 times more strongly than CDK6."

Copyright © KBR Unauthorized reproduction, redistribution prohibited