In a multicenter trial, the effect of a commercially available combination of autologous keratinocytes (3–6 × 106/mL) with fibrin sealant (Tissucol Duo S Immuno, Baxter Hyland Immuno) on the healing of recalcitrant venous leg ulcers (duration >3 months) was compared with standard care. The primary endpoint was time to healing, and the secondary endpoint was number of healed ulcers in both groups. Both groups received compression therapy with short-stretch bandages. Forty-four (38.3%) of the 116 patients who had BioSeed®-S treatment achieved complete healing of the target ulcer compared with 24 (22.4%) of 109 patients who received standard treatment. The advantage for treatment with BioSeed®-S over standard treatment was statistically significant (chi-square test: p=0.0106). Time to complete healing of ulcers: the log-rank test for equality over strata revealed a superiority of treatment with BioSeed®-S+compression (median: 176 days) over compression+standard care (median >201 days) (p<0.0001). This study, to date the largest multicenter study with autologous keratinocytes, provides evidence for its efficacy in the treatment of patients with therapy-resistant chronic venous leg ulcers.