Ashish Kamat, Professor and Director of Urologic Oncology Fellowship at MD Anderson Cancer Center, shared a post on X about a recent article he and his colleagues co-authored, adding:
“Pleased to share our new open-access meta-analysis in Journal Cancer: Event-free survival and complete response rate as surrogate endpoints for overall survival in high-risk NMIBC.
1. Why this matters: OS is the gold standard, but in HR NMIBC it takes years to mature – slowing trials and patient access to new therapies amid BCG shortages.
2. Context: About 75% of bladder cancers are NMIBC, and ~25% are high-risk. These patients face real progression risk, yet OS follow-up is long and confounded by competing mortality. This is why IBCG BladderCA and sit cancer recommended EFS (and CRR in select settings) – to enable faster, credible efficacy readouts.
What was missing was proof of surrogacy.
3. What we found, across randomized trials in BCG-naive or BCG-remote HR NMIBC: EFS showed a strong correlation with overall survival: • Trial-level R² ≈ 0.72 • Arm-level R² > 0.80
In practical terms, improvements in EFS reliably predicted improvements in survival, across decades of studies and varying definitions.
4. Some caveats: CR rate showed only modest correlation with OS, despite its appeal as an early endpoint. CRR may still be useful – especially for CIS and disease-specific outcomes – but it should not be overstated as a surrogate for long-term survival.
5.Take-home message: In BCG-naive or BCG-remote HR NMIBC, EFS is a meaningful endpoint. When well defined, it captures meaningful benefit earlier, aligns with patient priorities, and supports more efficient trial design.
This reinforces current IBCG BladderCA guidance and sets the stage for smarter trials with modern therapies.”
Title: Event-free survival and complete response rate as surrogate endpoints for overall survival in high-risk non–muscle-invasive bladder cancer: A meta-analysis of bacillus Calmette-Guérin—naive or —remote cases
Authors: Rituparna Bhattacharya, Kalé Kponee-Shovein, Yipeng Gao, Yan Song, Jingyi Liu, Katherine Wei, Ekta Kapadia, Haojie Li, Ashish M. Kamat
Read the full article on Cancer.
More posts featuring Ashish Kamat on OncoDaily.