Importance: Increasingly, cost-effectiveness analyses are being done to determine the value of rapidly increasing oncology drugs; however, this assumes that these analyses are unbiased.
Objective: To analyze the characteristics of cost-effectiveness studies and to determine characteristics associated with whether an oncology drug is found to be cost-effective.
Design, setting, and participants: This retrospective cross-sectional study included 254 cost-effectiveness analyses for 116 oncology drugs that were approved by the US Food and Drug Administration from 2015 to 2020.
Exposures: Each drug was analyzed for the incremental cost-effectiveness ratio per quality-adjusted life year, the funding of the study, the authors' conflict of interest, the threshold of willingness-to-pay, from what country's perspective the analysis was done, and whether a National Institute for Health and Care Excellence cost-effectiveness analysis had been done.
Main outcomes and measures: The main outcome was the odds of a study concluding that a drug was cost-effective.
Results: There were 116 drug approvals with 254 studies and country perspectives. Of the country perspectives, 132 (52%) were from the US. Forty-seven of 78 drugs with cost-effective studies had been shown to improve overall survival, whereas 15 of 38 of drugs without a cost-effectiveness study had been shown to improve overall survival. Having a study funded by a pharmaceutical company was associated with higher odds of a study concluding that a drug was cost-effective than studies without funding (odds ratio, 41.36; 95% CI, 11.86-262.23).
Conclusions and relevance: In this cross-sectional study, pharmaceutical funding was associated with greater odds that an oncology drug would be found to be cost-effective. These findings suggest that simply disclosing potential conflict of interest is inadequate. We encourage cost-effectiveness analyses by independent groups.