ESPAC-3

Background

Phase III RCT (ESPAC-3). 1,088 patients with resected pancreatic ductal adenocarcinoma at 159 centers in 8 countries. Randomized 1:1 to adjuvant gemcitabine or 5-FU/leucovorin for 6 months. Designed to determine the superior adjuvant chemotherapy backbone following ESPAC-1.

Interventions and follow up

Arm A: Gemcitabine 1,000 mg/m² days 1, 8, 15 every 4 weeks ×6 cycles
Arm B: 5-FU 425 mg/m² + leucovorin 20 mg/m² days 1–5 every 4 weeks ×6 cycles
Primary endpoint: Overall survival
Median follow-up: 34.2 months

Results

mOS: 23.6 months (gemcitabine) vs 23.0 months (5-FU/LV), HR 0.94, 95% CI 0.81–1.08, P=.39 — no significant difference
2-yr OS: 48.1% vs 49.1%

Adverse events

Gastrointestinal: Grade ≥3 stomatitis/mucositis higher with 5-FU (10% vs 2%); grade ≥3 diarrhea 13% vs 5%.
Other: Gemcitabine had more grade ≥3 alopecia; quality of life significantly better with gemcitabine.

Conclusions

Gemcitabine and 5-FU/LV were equivalent in OS after resection. Given superior tolerability and quality of life, gemcitabine became the preferred adjuvant agent, confirming the standard established by CONKO-001 but without a superiority claim over 5-FU.

Key Limitations

The study was powered for superiority and found none, so either drug is acceptable but neither was proven superior. Capecitabine (oral 5-FU prodrug) was not tested; subsequent ESPAC-4 showed gemcitabine + capecitabine superior to gemcitabine alone, suggesting the 5-FU backbone matters. At the time the largest adjuvant pancreatic trial conducted.

Clinical Context

ESPAC-3 confirmed gemcitabine as the backbone adjuvant agent due to better tolerability, consistent with CONKO-001. The next question — whether combination chemotherapy could improve on gemcitabine — was answered by ESPAC-4 (gemcitabine + capecitabine superior) and PRODIGE-24 (mFOLFIRINOX superior). ESPAC-3 remains the largest randomized adjuvant trial in resected pancreatic cancer.

References

References: Neoptolemos JP et al, JAMA 2010 (ESPAC-3)