Adjuvant Durvalumab Yields Improved Efficacy in NIAGARA Regimen

During the 2025 ASCO Genitourinary Cancer Symposium, CancerNetwork® spoke with Guru P. Sonpavde, MD, medical director of Genitourinary Oncology, assistant director of the Clinical Research Unit, and Christopher K. Glanz Chair for Bladder Cancer Research at the AdventHealth Cancer Institute about the phase 3 NIAGARA trial (NCT03732677), what he considers to be the “single most practice impacting abstract”.

The NIAGARA trial evaluated the efficacy of neoadjuvant gemcitabine (Gemzar) and cisplatin with and without durvalumab (Imfinzi) in patients with muscle-invasive bladder cancer. One of the major questions regarding this regime was whether patients who experienced a pathologic complete response (pCR) needed to receive the adjuvant durvalumab portion of the treatment. The presented results showed a benefit in patients who did receive the adjuvant durvalumab.

In the group of patients who underwent a pathologic complete response (pCR), the median event-free survival was not reached (NR; 95% CI, NR-NR) in the durvalumab arm vs NR months (95% CI, NR-NR) in the comparator arm (HR, 0.58; 95% CI, 0.332-0.999); median overall survival was NR (95% CI, NR-NR) vs NR (95% CI, NR-NR), respectively (HR, 0.72; 95% CI, 0.367-1.426).

Transcript:

The single most practice-impacting abstract might be the NIAGARA follow-up. NIAGARA was a large phase 3 study looking at neoadjuvant gemcitabine and cisplatin with or without durvalumab. The durvalumab was given, not only in the neoadjuvant phase of the treatment but also for 8 more cycles, or 8 months of treatment in the post-operative phase. The question has always been, in patients who have a pCR with gemcitabine/cisplatin/durvalumab, do you need the adjuvant durvalumab component? In this analysis, and remember, this regimen is still not approved—hopefully, it will be—but in this analysis, it suggests that whether the patients had [a pCR] or not, there seemed to be some benefit with the adjuvant component. Now, we are not at the point of saying that we can live without the adjuvant component. Further studies need to be done incorporating circulating tumor DNA and perhaps predictive biomarkers to select patients who might benefit from adding durvalumab to gemcitabine/cisplatin. But now, it’s interesting to see that [patients with a] pCR or [without a] pCR both seem to benefit, although the hazard ratios seem more impressive in the [patients with a] pCR group. Even the non-pCR group seems to have a hazard ratio [that shows] benefit [when] adding the adjuvant durvalumab.

References

Galsky M, Van Der Heijden M, Catto J, et al. Additional efficacy and safety outcomes and an exploratory analysis of the impact of pathological complete response (pCR) on long-term outcomes from NIAGARA. J Clin Oncol 43, 2025 (suppl 5; abstr 659). doi:10.1200/JCO.2025.43.5_suppl.659