Personal project using public CMS data
Medicare Part B oncology drug spending, 2020–2024
An interactive look at where provider-administered cancer-drug spending is concentrated, what drives its growth, and where biosimilars could lower cost. Built in Python/pandas from public CMS data. It isn't employer work.
2024 oncology Part B spend
$21.50B
Growth 2020→2024
+41%
Share of all Part B drug spend
35%
Top-10 drugs' share (2024)
68%
Oncology vs. all Part B drug spending
Top 10 oncology drugs, 2024
Together: 68% of 2024 oncology spend ($21.50B)
Tip: click a bar to drill into that drug below.
Drug drill-down: Keytruda (Pembrolizumab, J9271)
Price vs. volume, 2020→2024
Growth here is driven more by volume (use) than by price.
2024 beneficiaries: 75,361
Biosimilar adoption
Biosimilar share of spend
Spend: brand vs. biosimilars (hover for $)
2024 savings what-if
Avg spend per 10 mg unit: brand $76.27 vs. biosimilar $29.43 (61% lower).
$268.3M
Simple what-if: switched units × per-unit gap. It isn't a forecast and ignores clinical, contracting, and rebate effects.
Findings
- Oncology Part B drug spend rose from $15.3B (2020) to $21.5B (2024), up 41%. That is 35% of all Part B drug spending.
- Keytruda alone was $5.99B, or 28% of oncology spend. The top 10 drugs were 68%.
- Of the $6.25B added since 2020, $5.07B came from codes with no 2020 spending (new drugs and new formulations).
- Biosimilar share in 2024: bevacizumab 72%, trastuzumab 63%, rituximab only 41% (flat since 2021). Biosimilars cost 53–61% less per unit.
- For a specialty benefit manager: focus pathway programs on the few big immunotherapy and myeloma drugs, scan for new launches, and push rituximab biosimilar adoption.