It was in December 2018 that Tagrisso (osimertinib), an EGFR-mutated anticancer drug targeting non-small cell lung cancer (NSCLC), won approval for the first-line treatment of stage-4 patients in Korea.

AstraZeneca, which developed Tagrisso, has provided drug cost support to patients receiving first-line treatment through its expanded access program (EAP) since January 2019, shortly after approval. It is estimated that at least 500 to 600 patients per year have received drug cost assistance in their first-line treatment.

Tagrisso's drug expense support program still goes on.

During that time, Tagrisso has become the "global standard" for treating EGFR-mutant NSCLC. Most OECD countries recognize Tagrisso as a first-line treatment. Korea is one of the few countries, along with Slovakia, Latvia, and Turkestan, where insurance does not cover it.

After repeated failures in Korea, it also passed the Cancer Disease Review Committee, the first gateway to reimbursement, in March. It is now discussed at the Economic Evaluation Subcommittee. Still, few know the timing of Tagrisso's reimbursement for first-line treatment amid the government's endless requests for additional data.

Tagrisso's monthly medication costs more than 6 million won ($4,615). Even now, patients who take Tagrisso for first-line treatment are paying more than 4 million won per month out of their pockets.

Some have stopped treatment because they could not wait any further for reimbursement, while others have sold their homes to pay for their treatment. A patient's caregiver who spoke at a meeting to discuss reorganizing health insurance finance complained that she had to sell her home and move out after four years of Tagrisso treatment. There was no help from the state for these cancer patients and their families.

Recently, a homegrown new drug, Leclaza (lazertinib), has been added to the first-line treatment, improving the treatment environment for newly diagnosed stage 4 lung cancer patients.

That was because Yuhan Corps., the company that owns Leclaza, announced that it would cover the full cost of Leclaza until its insurance coverage, meaning that patients diagnosed with stage-4 EGFR-mutated NSCLC can now choose from two third-generation targeted anticancer drugs. If they choose Leclaza, they will receive full coverage.

What hasn't changed, however, is that patients receiving first-line treatment with Tagrisso for the past four-and-a-half years are still paying more than 4 million won per month out of pocket, and the government is completely ignoring them.

There's another aspect to the delayed reimbursement for Tagrisso that the government is overlooking; Korea may be excluded from developing a follow-up treatment. The treatment of EGFR-mutated NSCLC is based on targeted anticancer drugs, and EGFR TKIs inevitably lead to resistance.

A fourth generation of agents is now being developed worldwide to treat patients who have developed resistance to Tagrisso. All are being tested in clinical trials in patients previously treated with Tagrisso. This is because Tagrisso is the only global standard treatment. Only Korea and China use third-generation EGFR TKIs other than Tagrisso in clinical practice.

As a result, the development of fourth-generation drugs by Western pharmaceutical companies will center on patients who have developed resistance to Tagrisso. Furthermore, if most countries reimburse first-line Tagrisso, Korea will be even less likely to participate in developing fourth-generation drugs by global pharmaceutical companies due to its disparity in clinical practices.

This exclusion from clinical studies will inevitably lead to delays in approving future fourth-generation drugs. But that’s not the end of the story. Tagrisso's delayed payment could also hurt domestic companies developing fourth-generation drugs. If you're developing a global drug and the clinical environment in your home country is different from the global one, the difference will translate into higher development costs.

In the end, the government should keep in mind that Tagrisso's delayed payment is not just a grievance for some patients receiving drug subsidies. It is also closely linked to the future of lung cancer treatment in Korea and the interests of the domestic pharmaceutical industry.

Most importantly, the government should recognize that patients and their families are left to bear the brunt of the difficult cancer treatment journey without government support.