Serametrix MDSC Assay Being Utilized By Infinity Pharmaceuticals in the First Clinical Study to Prospectively Identify Patients With High Blood Levels of MDSCs

First Patient Enrolled in IPI-549 Plus OPDIVO® MDSC-High Cohort in Infinity Pharmaceuticals Ongoing IPI-549-01 Phase 1/1b Clinical Trial

Carlsbad, CA. – May 22, 2018 Today Serametrix Corporation announced that Infinity Pharmaceuticals, Inc. (NASDAQ: INFI) has enrolled the first patient in a clinical trial in which the Serametrix MDSC Assay is being used to pre-select patients having high baseline blood levels of myeloid derived suppressor cells (MDSCs). Screening samples will be analyzed at the Serametrix CLIA certified laboratory. Studies have shown that poor response to checkpoint inhibitor therapy is correlated with the presence of high baseline blood levels of MDSCs in cancer patients.1,2,3,4 This is the first clinical trial in which patient blood levels of MDSCs are being used as an enrollment criterion. Baseline and on-treatment MDSC levels will be measured in approximately 100 patients in the combination expansion phase of the IPI-549-01 study now underway evaluating IPI-549 plus Opdivo. This includes the 20 patient MDSC high cohort in which patients will be pre-screened and selected for high baseline blood levels of MDSCs. Additionally, the pre and on-study MDSC blood levels of approximately 80 patients in 6 disease specific cohorts in the IPI-549-01 study will be analyzed.  These data will be used to assess the relationship between MDSC levels, intratumoral M2 macrophage levels, and response to combination therapy across a range of tumor types. Financial details were not disclosed.

“We are delighted to be supporting Infinity’s patient enrollment for this potentially groundbreaking study,” said Henry Hepburne-Scott, Ph.D., Chief Scientific Officer at Serametrix. “This is an important step in our development of companion diagnostic tests for PD-1 and other checkpoint blockades,” he added.

Accurate testing for this important cell type in cancer patients has previously been difficult to achieve. The Serametrix assay, which gained CLIA status last year, utilizes a proprietary algorithm for reliable data analysis. This unique algorithm was developed in the laboratory of Jedd Wolchok, M.D., Ph.D., at Memorial Sloan Kettering Cancer Center and licensed by Serametrix in 2013.  Dr.Wolchok is also the primary investigator on Infinity’s Phase 1/1b study of IPI-549.

“IPI-549, our first-in-class oral immuno-oncology product candidate that selectively inhibits phosphoinositide-3-kinase-gamma (PI3K-gamma) has anti-MDSC activity in preclinical studies5,” said Jeffery Kutok, M.D., Ph.D., Chief Scientific Officer at Infinity Pharmaceuticals. “Preliminary translational data from the dose escalation component of Infinity’s IPI-549-01 Phase 1/1b study suggested an association between high baseline blood levels of MDSCs and clinical responses. Pre-selecting patients with high blood levels of MDSCs could therefore lead to improved clinical activity for patients treated with the combination of IPI-549 and anti-PD1. The Serametrix MDSC assay enables us to evaluate in the clinic whether IPI-549 can improve response rates to Opdivo in patients with elevated blood levels of MDSCs.”

About IPI-549 and the Ongoing Phase 1/1b Study

IPI-549 is an investigational first-in-class, oral, immuno-oncology product candidate targeting tumor-associated myeloid cells through selective PI3K-gamma inhibition, thereby reducing pro-tumor macrophage function and increasing anti-tumor macrophage function. In preclinical studies, IPI-549 reprograms macrophages from a pro-tumor (M2), immune suppressive function, to an anti-tumor (M1) immune activating function and can enhance the activity of, and overcome resistance to, checkpoint inhibitors.5,6  IPI-549 can also overcome the suppressive effects of MDSCs on T-cell proliferation5.  As such, IPI-549 may have the potential to treat a broad range of solid tumors and represents a potentially additive or synergistic approach to restoring anti-tumor immunity in combination with other immunotherapies such as checkpoint inhibitors.

The ongoing Phase 1b study being conducted by Infinity is designed to evaluate the safety, tolerability, activity, pharmacokinetics and pharmacodynamics of IPI-549 as a monotherapy and in combination with Opdivo in approximately 200 patients with advanced solid tumors.7  The study includes monotherapy and combination dose-escalation components, in addition to monotherapy expansion and combination expansion components. The monotherapy dose-escalation component is complete, and the monotherapy expansion component has been fully enrolled.  The combination dose-escalation component is also complete, and combination expansion cohorts are enrolling.

The combination expansion component of the study includes multiple cohorts designed to evaluate IPI-549 in patients with specific types of cancer, including patients with non-small cell lung cancer, melanoma and head and neck cancers whose tumors show initial resistance or initially respond to but subsequently develop resistance to immune checkpoint blockade therapy. The combination expansion component also includes a cohort of patients with triple negative breast cancer who have not been previously treated with immune checkpoint blockade therapy, a cohort of patients with mesothelioma, a cohort of patients with adrenocortical carcinoma and a cohort of patients with high baseline blood levels of MDSCs.

IPI-549 is an investigational compound and its safety and efficacy has not been evaluated by the U.S. Food and Drug Administration or any other health authority.

About Serametrix Corporation

Serametrix provides solutions to the problem of monitoring immune response to immunotherapies in clinical trial cancer patients.  In partnership with the Ludwig Institute for Cancer Research (LICR) and other leading institutes Serametrix has developed a suite of immunoassays that monitor anti-tumor immunity in patients enrolled into clinical trials for novel cancer therapies.  Serametrix is part owned by the LICR.

About Infinity

Infinity is an innovative biopharmaceutical company dedicated to advancing novel cancer treatments. Infinity is advancing IPI-549, a potentially transformative immuno-oncology approach that aims to reprogram tumor-associated macrophages by selectively inhibiting PI3K-gamma. A Phase 1/1b study in approximately 200 patients with advanced solid tumors is ongoing. For more information on Infinity, please refer to Infinity’s website at

1. Kitano et al. Myeloid Derived Suppressor Cell Quantity Prior to Treatment with Ipilimumab at 10mg/kg Predicts for Improved Overall Survival in Patients with Metastatic Melanoma. ASCO annual meeting #2518, 2013.

2. Postow et al. Immunologic Correlates of the Abscopal Effect in a Patient with Melanoma. NEJM 2012, 366;10.

3. Kitano et al. Computational Algorithm-Driven Evaluation of Monocytic Myeloid-Derived Suppressor Cell Frequency For Prediction of Clinical Outcomes. Cancer Immunol Res. 2014, 2(8): 812.

4. Weber et al. Phase I/II Study of Metastatic Melanoma Patients Treated with Nivolumab Who Had Progressed after Ipilimumab. Cancer Immunol Res 2016, 4(4) : 1.

5. De Henau, O., Rausch, M., Winkler, D., Campesato, L., et al. Overcoming resistance to checkpoint blockade therapy by targeting PI3Kγ in myeloid cells. Nature, 2016 Nov;539:443-447.

6. Kaneda, M., Messer, K., Ralainirina, N., Li, H., et al. PI3Kγ is a molecular switch that controls immune suppression. Nature, 2016 Nov;539:437–442.

7., NCT02637531.