immatics announces Phase II Results with its Therapeutic Cancer Vaccine IMA901 in Patients with Advanced Renal Cell Carcinoma at ASCO

Results of multi-center phase II trial highlight the promise of cancer vaccines in showing strong signal for improved survival with significant correlation of immune response and survival and excellent safety profile

Randomized, controlled, pivotal trial in preparation

Tuebingen, 5 June, 2010 - immatics biotechnologies GmbH, a clinical-stage biopharmaceutical company developing advanced therapeutic vaccines that are active against cancer, announced that results from its Phase II clinical trial with IMA901 in patients with advanced renal cell carcinoma were presented at the 46th Annual Meeting of the American Society of Clinical Oncology (ASCO) in Chicago. Following discussions with key opinion leaders, immatics plans to start a randomized, controlled pivotal clinical trial with IMA901 based on the positive outcomes from this Phase II study which highlighted the vaccine’s potential to confer a survival benefit in patients with advanced renal cancer.

The exploratory Phase II study recruited 68 patients with advanced/metastatic renal cell carcinoma who had failed previous first line therapy (either tyrosine kinase inhibitors (TKI) or cytokines). Patients in the study were randomized to receive one single infusion of cyclophosphamide (CY) as immunomodulator prior to the first vaccination with the multi-peptide vaccine IMA901. The study investigated disease control rate (DCR) at 6 months, progression-free survival, overall survival, correlation of immune response with clinical benefit, and safety and tolerability.

Patients randomized to receive a single dose of CY showed a strong trend towards improved overall survival versus patients who did not receive CY (p=0.086; median OS not reached after 23 months of follow-up in the CY-pretreated patients versus median OS of 16 months in the other patients). The survival data of this study compares very favorably to previous studies of the approved tyrosine kinase inhibitors sunitinib and sorafenib.

The relevance of this finding was further supported by data showing that CY – as prospectively hypothesized – significantly reduced regulatory T cells (Tregs), an immune cell population thought to inhibit TUMAP-specific immune responses. Finally, patients who were able to mount a vaccine-induced immune response against tumor-derived peptides contained in IMA901, showed significantly longer survival compared to those who did not (p=0.048 in all patients and p=0.006 in CY-pretreated patients).

With regard to the short-term endpoint DCR at 6 months, the study showed a strong trend towards an improvement compared to a prospectively defined no-effect threshold. The favorable safety profile observed in the previous phase I study was confirmed with most drug-related adverse events being mild local site reactions.

Paul Higham, CEO of immatics said: “The phase II trial results with our lead therapeutic vaccine IMA901 to treat patients with advanced renal cell carcinoma are highly encouraging. The overall survival that we have seen compares very well with published clinical data generated with currently marketed treatments for this severe form of cancer. The fact that we have seen this potential survival benefit is important given the regulatory authorities’ recognition of survival as the key efficacy endpoint for cancer vaccines. Additionally, we have confirmed the mechanism of action of IMA901 by demonstrating a significant association of immune response with clinical benefit in two independent trials. Based on these positive data and the feedback we have received from our lead investigators we have decided to conduct a randomized, controlled pivotal study as soon as possible.”

The Study
The phase II study was carried out at 23 centers in 10 European countries. Patients in the study were stratified for risk group and previous treatment and randomized to receive one single infusion of cyclophosphamide (CY; 300mg/m2) prior to the first vaccination with IMA901. Both groups of patients then received up to 17 injections of IMA901 plus GM-CSF (both intradermally) over a period of up to 9 months. CY was introduced to evaluate the impact as an additional immunomodulator as it had been observed that patients with lower regulatory T cells had a better outcome in the IMA901 phase I study.

Two posters that were presented at ASCO and which contain a more detailed analysis of the survival, safety and immune response data generated with IMA901 in this phase II study can be accessed here.

About IMA901
IMA901 is therapeutic cancer vaccine comprising 10 tumor-associated peptides (TUMAPs) that are frequently found to be over-expressed in the majority of patients suffering from renal cell carcinoma. As with all immatics’ vaccines, IMA901 has been designed to elicit a strong, clinically relevant immune response to a specific tumor type. The TUMAPs were selected from in over 2,000 peptides identified via immatics’ unique XPRESIDENT™ platform. TUMAPs included in IMA901 are from targets with vital functions for the tumor, for example invasion, neo-angiogenesis.

-/ Press release_IMA901 results_100506_english (PDF, 116 KB)

-/ Pressemitteilung_IMA901 Ergebnisse_100605_deutsch (PDF, 121 KB)