A Randomized Phase 2/3 Study of Naptumomab Estafenatox + IFN-α vs IFN-α in Renal Cell Carcinoma: Final Analysis with Baseline Biomarker Subgroup and Trend Analysis.

To prospectively determine the efficacy of naptumomab estafenatox (Nap) + interferon α (IFN) versus IFN in metastatic renal cell carcinoma (RCC).

In a randomized, open-label, multicenter, phase 2/3 study, 513 RCC patients received Nap (15 µg/kg intravenously in three cycles of four once daily injections) + IFN (9 MU subcutaneously three times weekly) or the same regimen of IFN monotherapy.

The primary endpoint was overall survival (OS).

This phase 2/3 study did not meet its primary endpoint. Median OS/PFS for Nap+IFN patients was 17. 1/5. 8 months versus 17. 5/5. 8 months for the patients receiving IFN alone (p=0. 56, hazard ratio 1. 08/p=0. 41, hazard ratio 0. 92). Post-hoc exploratory subgroup and trend analysis revealed that the baseline plasma concentrations of anti-SEA/E-120 (anti-Nap antibodies) for drug exposure and IL-6 for immune status could be used as predictive biomarkers. A subgroup of patients (SG; n=130) having concentrations below median of anti-SEA/E-120 and IL-6 benefitted greatly from addition of Nap. In SG median OS/PFS for the patients treated with Nap+IFN was 63. 3/13. 7 months versus 31. 1/5. 8 months for the patients receiving IFN alone (p=0. 02, hazard ratio 0. 59/p=0. 02, hazard ratio 0. 62). Addition of Nap to IFN showed predicted and transient immune related AEs and the treatment had an acceptable safety profile.

The study did not meet its primary endpoint. Nap+IFN has an acceptable safety profile and results from post-hoc subgroup analyses showed that the treatment might improve OS/PFS in a baseline biomarker defined RCC patients subgroup. The results warrant further studies with Nap in this subgroup.

Clinical cancer research : an official journal of the American Association for Cancer Research. 2016 Feb 05 [Epub ahead of print]

Robert E Hawkins, Martin Gore, Yaroslav Shparyk, Vladimir Bondar, Oleg Gladkov, Tosho Ganev, Mihai Harza, Serhii Polenkov, Igor Bondarenko, Petr Karlov, Oleg Karyakin, Rustem Khasanov, Gunnar Hedlund, Goran Forsberg, Orjan Nordle, Timothy Eisen

Medical Oncology, Christie CRC Research Centre  Gynecological Oncology Unit, Royal Marsden Hospital. , Unknown, Lviv State Regional Treatment and Diagnostics Oncology Center. , unknown, Public Clinical Treatment and Prophylaxis Institution: Donetsk Regional Antitumor Center. , Clinical Oncology, Chelyabinsk Regional Clinical Oncology Center. , unknown, PhD, Urology Clinic General Hospital for Active Treatment. , Unknown, Fundeni Clinical Institute. , Unknown, Public Treatment and Prophylaxis Institution: Chernihiv Regional Oncology Center. , Oncology and Medical Radiology Department, Dnipropetrovsk Municipal Clinical Hospital. , Unknown, Municipal Clinical Oncology Center. , Unknown, Medical Radiology Research Center under the Ministry of Healthcare of Russian Federation. , Unknown, Republican Clinical Oncology Center of Ministry for healthcare of the Republic of Tatarstan. , Scientific Affairs, Active Biotech Research AB. , Unknown, Active Biotech AB. , Biostatistics, Active Biotech. , Addenbrooke's Hospital, Cambridge Biomedical Campus.

PubMed