Cost Difference Between Two Lung Cancer Drugs in Japan

In Japan, doctors often treat extensive‑stage small cell lung cancer with a platinum‑based chemo drug plus etoposide, and then add one of two immunotherapy medicines: atezolizumab or durvalumab. Both combos are used as the first line of care. Early trials showed they work about the same, but no head‑to‑head test has been done, and the price tag and hospital resources can differ.

Researchers pulled records from eight hospitals across the country. They looked at patients who got the chemo plus either atezolizumab or durvalumab between August 2018 and December 2022. After removing those who got cisplatin and using a scoring method to balance groups, 128 people stayed in the analysis. The average age was about 74, and most were men. The team calculated monthly medical bills from insurance claims and checked survival, serious immune side effects, and lung inflammation.

The monthly bill was markedly lower for atezolizumab: roughly ¥1,000,000 (about $7,200) versus ¥1,600,000 (about $11,400) for durvalumab. Survival times were almost identical, around 14 months for each group. Serious immune reactions happened in about one‑tenth of the atezolizumab group compared with nearly a third of the durvalumab group, and lung inflammation was far less common with atezolizumab. The only factor that clearly worsened survival was poor performance status; the choice of drug did not.