Background: Post-hoc analyses of AFP response and progression and their relationship with objective measures of response and survival were performed in patients from REACH.
Methods: Serum AFP was measured at baseline and every 3 cycles (2 weeks/cycle). Associations between AFP and radiographic progression and efficacy end points were analysed.
Results: Median percent AFP increase from baseline was smaller in the ramucirumab than in the placebo arm throughout treatment. Time to AFP progression (HR 0.621; P < 0.0001) and to radiographic progression (HR 0.613; P < 0.0001) favoured ramucirumab. Association between AFP and radiographic progression was shown at 6 (OR 6.44, 95% CI 4.03, 10.29; P < 0.0001) and 12 weeks (OR 2.28, 95% CI 1.47, 3.53; P = 0.0002). AFP response was higher with ramucirumab compared with placebo (P < 0.0001). More patients in the ramucirumab arm experienced tumour shrinkage and AFP response compared with placebo. Survival was longer in patients with AFP response (13.6 months) than in patients without (6.2 months), irrespective of treatment (HR 0.457, P < 0.0001).
Conclusions: Treatment with ramucirumab prolonged time to AFP progression, slowed AFP increase and was more likely to induce AFP response. Similar benefits in radiographic progression and response correlated with AFP changes.