BACKGROUND: The US Food and Drug Administration (FDA) has expanded the use of surrogate markers in drugs approved for oncology/hematology indications. This has likely resulted in a greater number of approvals and possibly drugs coming to market faster, but it is unknown whether these drugs also improve overall survival (OS) for patients taking them. METHODS: We sought to estimate the percentage of oncology drugs that have shown to improve OS in a cross-sectional analysis of US FDA oncology drug approvals (2006-2023). We searched for OS data in registration trials and the peer-reviewed literature. RESULTS: We found 392 oncology drug approvals. Eighty-seven (22%) drug approvals were based on OS, 147 drug approvals were later tested for OS benefit (38% of all approvals and 48% of drugs approved on a surrogate), and 130 (33%) have yet to be tested for OS benefit. Of the 147 drug approvals later tested for OS, 109 (28% of all approvals and 74% of drugs later tested for OS) have yet to show OS benefit, whereas 38 (10% of all approvals and 26% of drugs later tested for OS benefit) were later shown to have OS benefit. In total, 125 out of 392 (32%) drugs approved for any indication have been shown to improve OS benefit at some point, and 267 (68%) have yet to show approval. CONCLUSION: About 32% of all oncology drug approvals have evidence for an improvement in OS. Higher standards are needed in drug regulation to ensure that approved drugs are delivering better patient outcomes, specifically in regards to survival.

Background

Immune checkpoint inhibitor (ICI) therapies have become increasingly popular treatment options for patients with cancer, even for patients in non-metastatic settings. Survival and responses have been reported for individual tumor types, but little is known about these outcomes, collectively. We sought to provide an overview of overall survival (OS) and progression-free survival (PFS) in ICI drugs tested in registration trials.

Methods

In a cross-sectional analysis of US FDA oncology ICI drug approvals (2011-2023), we searched for supporting ICI registration trials. We characterized these trials, regarding differences in median OS and PFS between patients in intervention and control arm participants in ICI registration trials; percentage of patients who receive ICI crossover; and whether there is correlation between the percentage of crossover and differences in OS or PFS.

Results

Fifty-six (54.4 %) approvals had trials that reported median OS for both intervention and control arms (median difference was 2.8 months; IQR: 2.2 to 5.0 months). Sixty-five (63.1 %) approvals had trials that reported PFS data for both arms (median of 0.9 months; IQR: -0.2 to 3.0 months). Subsequent therapy was common (median=18.9 %) and was significantly correlated with a higher difference in median OS in all studies with reported differences (R2 =0.15; p = 0.001).

Conclusion

ICIs are increasingly used in the treatment of cancer, yet the median OS improvement is modest, and many ICIs have not been tested for OS benefit. OS is the outcome most meaningful for patients, and drug regulation should require better testing and reporting of these data.