Imfinzi’s bid for coverage faces Keytruda’s double-edged impact in Korea

AstraZeneca's immuno-oncology drug Imfinzi (durvalumab) is attempting to expand its reimbursement coverage, but its competitor, MSD's Keytruda (pembrolizumab), is acting as a complex variable.

In other words, Keytruda has become a double-edged sword for its rival drug: pressuring Imfinzi’s price downward while simultaneously creating a short-term opportunity in bile duct cancer.

Imfinzi, an anti-PD-L1 immune checkpoint inhibitor developed by AstraZeneca, secured approval in Korea in December 2018. Since then, it has gained approval for eight indications, including lung cancer, bile duct cancer, liver cancer, uterine cancer, and bladder cancer.

However, only one indication -- adjuvant therapy for unresectable stage 3 non-small cell lung cancer (NSCLC) -- qualifies for the state health insurance coverage for Imfinzi treatment.

This was a strategic choice by AstraZeneca, since pursuing reimbursement in more competitive indications would have forced steep price cuts. The out-of-pocket monthly cost for Imfinzi is approximately 10 million won ($7,133), making it expensive compared to other immuno-oncology drugs.

However, AstraZeneca could no longer delay expanding Imfinzi's coverage. Ultimately, it prioritized expanding coverage for bile duct cancer and first-line liver cancer treatment, where competition is relatively limited.

Imfinzi, which was reviewed by the Pharmaceutical Reimbursement Evaluation Committee (PREC) early this month, received a “re-examination” decision. Despite passing the Cancer Disease Review Committee (CDRC) last November and waiting over 10 months for the PREC, the result was a re-examination. AstraZeneca is now awaiting the resubmission of the Imfinzi agenda to the PREC scheduled for Thursday.

Some observers interpret that changes in the situation of the competing drug, Keytruda, may have influenced the reimbursement discussions for Imfinzi. This is because, on the same day, the PREC approved the expansion of coverage for Keytruda across 11 indications.

If Keytruda successfully negotiates its drug price and secures expanded coverage for these 11 indications, accompanied by a significant price reduction, this will directly impact the cost-effectiveness evaluation of Imfinzi. This is because Imfinzi shares the same indications for first-line treatment of bile duct cancer.

Currently, the monthly out-of-pocket cost for Keytruda is around 5 million won. If its price falls further, this will inevitably put direct pressure on Imfinzi's price negotiations.

However, Keytruda's expanded coverage does not solely have a negative impact on Imfinzi. From the government's perspective, which must ensure patient choice in first-line bile duct cancer treatment, it could instead face pressure to include Imfinzi in the coverage list.

While Keytruda's 11 indications approved by the PREC include bile duct cancer, this is limited to second-line or later monotherapy. It excludes first-line combination therapy, which directly competes with Imfinzi. The industry believes that Keytruda will likely face difficulties in pursuing further coverage expansions in the near term due to the price reduction burden resulting from this blanket coverage expansion for its 11 indications.

Consequently, in the short term, Imfinzi is effectively the only immunotherapy offering reimbursement benefits for first-line treatment of bile duct cancer. From the government's perspective, the complete absence of reimbursement options for first-line bile duct cancer treatment is inevitably burdensome.

Meanwhile, discussions on expanding Imfinzi's coverage for liver cancer are also complex. Particularly in first-line liver cancer treatment, Imfinzi is used in combination therapy with the anti-CTLA-4 immune checkpoint inhibitor Imjudo (tremelimumab)’, intertwining with the issue of establishing coverage for Imjudo.

The combination therapy of Tecentriq (atezolizumab), an immune checkpoint inhibitor with the same mechanism as Imfinzi, and the VEGF inhibitor Avastin (bevacizumab) is already established as the standard first-line treatment for liver cancer. Additionally, the dual immune therapy of Imfinzi + Imjudo, and the combination of Opdivo (nivolumab) + Yervoy (ipilimumab) combination therapy, identical to the dual immunotherapy of Imfinzi and Yervoy, is awaiting being tabled on PREC.

Some analysts suggest that Imfinzi could gain price competitiveness as BMS and Ono Pharmaceutical maintain their high-price strategy. However, the situation remains complex due to the requirement for pharmaceutical companies to align their pricing with the current standard therapy, Tecentriq + Avastin.

The government faces a two-sided choice. While the expanded coverage of Keytruda puts downward pressure on Imfinzi's price, the need to cover Imfinzi is growing to fill the gap in first-line treatment for bile duct cancer.

“While structural challenges like insurance fund burdens and drug price negotiations exist, it's difficult to rule out the possibility of Imfinzi being adopted as a covered option for first-line bile duct cancer treatment to ensure patient choice,” an industry executive said while requesting anonymity.

The direction of Imfinzi's coverage expansion hinges on the outcome of its re-evaluation by the PREC next month. With Keytruda simultaneously bringing about the contrasting effects of “price pressure” and “opportunity creation,” the industry is watching intently what outcome Imfinzi will face in this review.