The Glioma Actively Personalized Vaccine Consortium (GAPVAC; funded by the European Union Framework 7 Program) aims at treating newly diagnosed glioblastoma (GB) patients with two distinct actively personalized vaccines (APVACs).

Resected tumor material is analyzed for multiple biomarkers to characterize the tumor in depth and to enable the design of APVACs tailored to each individual patient: Tumor-specific mutations, the HLA peptidome and gene expression profile are assessed by next-generation sequencing, mass spectrometry and RNA microarray analysis, respectively. Further, the patient-individual immune status is investigated by assessment of leukapheresis samples utilizing an in vitro immunogenicity platform. Data are integrated to define two distinct APVACs for each patient: APVAC1 is composed of up to ten peptides selected from a pre-manufactured “warehouse”. The warehouse contains 59 HLA class I-binding and three class II-binding tumor-associated peptides frequently over-presented in GB. APVAC2 is composed of one or two peptides that are de novo synthesized for a given patient and preferentially represent mutation-bearing neo-epitopes.

After a preparation phase in which the warehouse was generated and setup of APVAC selection and manufacturing processes took place, the GAPVAC-101 phase I clinical trial was initiated. Primary endpoints of the study are assessment of safety, feasibility of APVAC manufacturing and biological activity.

The trial is conducted at six European centers and recruits HLA-A*02:01 or A*24:02-positive patients with newly diagnosed GB after gross total resection. Patients receive APVAC1 and APVAC2 vaccinations plus immunomodulators (poly-ICLC and GM-CSF) three and six months post study enrolment, respectively, and concurrent to maintenance temozolomide (TMZ).

As of November 2015, 11 patients have been enrolled, of whom six already received APVAC vaccines. Composition and manufacturing are ongoing for four patients. All APVACs were generated in time without ultimate failures. APVAC1 vaccines differ substantially with 31 out of 59 warehouse peptides have been selected at least once, indicating the need for personalization due to tumor heterogeneity even for non-mutated epitopes. In patients’ tumor samples an average of 40 non-synonymous mutations (including known driver mutations) were identified. Injection site reactions were the most frequent toxicities so far. One brain edema (Grade 3) and one allergic reaction (Grade 4)were observed, both potentially related to the vaccinations. First data on biological activity of APVACs and updated clinical data will be presented at the Annual Meeting.

In conclusion, the GAPVAC concept has been successfully translated into the clinics and so far demonstrated to be safe and feasible with its level of personalization matching the observed tumor heterogeneity.

Citation Format: Norbert Hilf, Katrin Frenzel, Sabrina Kuttruff-Coqui, Sandra Heesch, Sebastian Kreiter, Arie Admon, Valesca Bukur, Sjoerd van der Burg, Cecile Gouttefangeas, Judith R. Kroep, Marij Schoenmaekers-Welters, Jordi Piro, Berta Ponsati, Hans Skovgaard Poulsen, Ulrik Lassen, Francisco Martinez-Ricarte, Jordi Rodon, Juan Sahuquillo, Monika Stieglbauer, Stefan Stevanovic, Per thor Straten, Marco Skardelly, Ghazaleh Tabatabai, Michael Platten, David Capper, Andreas von Deimling, Valérie Dutoit, Hideho Okada, Christian Ottensmeier, Randi Kristina Feist, Jens Fritsche, Karoline Laske, Peter Lewandrowski, Martin Löwer, Regina Mendryzk, Miriam Meyer, Carsten Reinhardt, Bernhard Rössler, Anna Paruzynski, Nina Pawlowski, Colette Song, Stevermann Lea, Toni Weinschenk, Christoph Huber, Hans-Georg Rammensee, Pierre-Yves Dietrich, Wick Wolfgang, Ugur Sahin, Harpreet Singh-Jasuja. GAPVAC-101 phase I trial: First data of an innovative actively personalized peptide vaccination trial in patients with newly diagnosed glioblastoma. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 2654.