Active immunotherapy in patients with progressive disease (PD) after first-line therapy: Racotumomab experience.
3086 Background: Racotumomab is a therapeutic vaccine that induces a cellular and humoral immune response against NeuGc-containing gangliosides expressed in several tumors but not in normal human tissues. A previous randomized, double blinded, placebo-controlled trial has demonstrated low toxicity of racotumomab and a statistically significant benefit in overall survival (OS) in patients with advanced non-small-cell lung cancer (NSCLC) who had achieved partial or complete response or disease stabilization after first line therapy. Methods: An open, non-randomized study was performed to evaluate if racotumomab could also be beneficial in patients with progressive disease. Patients with recurrent and advanced stages (IIIB/IV) of NSCLC, in progression after completion of first-line onco-specific treatment as per the NCCN Oncology Therapeutic Guidelines (surgery, chemotherapy and/or radiotherapy) were included in the study. Most of them had received 4 to 6 cycles of cisplatin/vinblastin. Vaccination consisted of 5 intradermic doses of racotumomab (1 every 14 days), followed by 1 dose every 28 days until patient refusal or worsening of ECOG status. The patients did not receive second-line therapy. Results: 180 patients were included in an intent to treat (ITT) survival analysis (Kaplan Meier estimate), after at least 10 months of follow-up. Median survival was 8.06 months. OS rate (%) at 24 months was 21%. A control group of 85 consecutive patients treated at the same institution by the same investigators, who did not receive second-line therapy or racotumomab showed a median survival of 6.26 months (log rank test p= 0.011). OS rate (%) at 24 months was only 7%. A per protocol survival analysis including only the 124 patients (68.8%) who received ≥ 5 doses of racotumomab showed a median survival of 12 months. OS rate (%) at 24 months was 30%. Conclusions: Patients with PD after first-line treatment show favorable results in survival when vaccinated with racotumomab. This result is similar to previous clinical trials where racotumomab was administered to patients with objective response (partial or complete) or stable disease after first line therapy.