How much of a cancer drug is too much? Patients, researchers challenge FDA-approved dosages

“There is incredible uncertainty in drug dosing.”

By
Arthur Allen
August 20, 2026
15 min

Kff Health News

Objective:

To explore the challenges and implications of FDA-approved dosages of cancer drugs, particularly in light of patient experiences and emerging research on lower dosages.

Approach:

Patient Experience: Chuck Manski, an economist and cancer patient, opted to stop his nivolumab treatment early due to severe side effects, questioning the necessity of the full year of treatment as recommended by the FDA.
International Practices: Manski's decision aligns with practices in other countries where lower doses or shorter treatment durations of nivolumab and pembrolizumab are used.
Economic Considerations: Research indicates that optimizing dosages could save billions in healthcare costs and reduce side effects, yet dose-optimization studies are rare post-approval.

Key Findings:

43% of U.S. adults reported skipping medication due to cost.
30% of cancer drug prescriptions went unfilled among Medicare enrollees.
Using minimum necessary dosages could save the U.S. healthcare system approximately $31 billion in 2024.

Limitations:

Pharmaceutical companies have little incentive to study lower dosages due to profit motives.
Legal concerns may deter oncologists from prescribing lower-than-labeled dosages.