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Home » Rottapharm Biotech announces the first patient dosed in the Phase 1/2 study of the EP4 receptor antagonist CR6086 combined with Agenus’ anti-PD-1 balstilimab in advanced colorectal cancer

Rottapharm Biotech announces the first patient dosed in the Phase 1/2 study of the EP4 receptor antagonist CR6086 combined with Agenus’ anti-PD-1 balstilimab in advanced colorectal cancer

December 13, 2021

Monza (Italy) – Rottapharm Biotech announces dosing the first patient in the Phase 1/2 study of CR6086 in combination with Agenus’ balstilimab (anti-PD-1) in advanced colorectal cancer at the National Cancer Institute (Istituto Nazionale dei Tumori) – Milan (Italy).

Patients with colorectal cancers have limited treatment options, as most do not respond to PD-1 therapy or other immunotherapy regimens studied to date. Colorectal cancers represent one of the three most common cancers diagnosed, and the second leading cause of deaths across all cancer types globally. More than 80% of colorectal cancers are classified as mismatch repair-proficient (pMMR) and microsatellite stable (MSS) colorectal cancer (CRC), which correlates with low tumor mutation burden and poor immune cell infiltration within the tumor microenvironment (“cold tumors”). These patients generally do not benefit from PD-1 therapy alone and combination strategies with other immune-modulating therapies are necessary to address immune suppression in the tumor microenvironment and improve sensitivity to PD-1 therapy.

The involvement of prostaglandin E2 (PGE2) in cancerogenesis has been known for decades. There is now growing evidence about the role of PGE2, via its EP4 receptor on different immune cells, as a key effector for the impaired immune response within the tumor microenvironment and the potential for an EP4 receptor antagonist to turn the tumor microenvironment into an immune-responsive (“hot”) tissue.

Rottapharm Biotech is developing CR6086, a potent and selective small molecule antagonist of EP4. EP4 signaling broadly suppresses immune activity in the tumor microenvironment, contributing to treatment resistance and tumor progression. CR6086 is designed to increase the activity and infiltration of several different immune cell types – including T cells, natural killer cells, and dendritic cells – while blocking the immune suppressive role of PGE2 in the tumor microenvironment. Preclinical evidence suggests that CR6086 may work in combination with PD-1 therapy to promote durable, anti-tumor immune responses. CR6086 is a potential best-in-class EP4 receptor antagonist, based on its pharmacokinetics and pharmacodynamic profile, and has demonstrated a strong safety profile in >250 subjects treated to date.

Balstilimab is a monoclonal antibody developed by Agenus Inc., belonging to the immune checkpoint inhibitor class, and is an inhibitor of programmed cell death 1 (PD-1) protein. It has been evaluated in >400 patients to date and has demonstrated strong clinical activity and an excellent safety profile in several tumor types, including cervical cancer (results published in Gynecologic Oncology this year).

The Phase 1/2 clinical study aims at evaluating the safety and efficacy of CR6086 combined with balstilimab in patients with advanced pMMR/MSS metastatic CRC (mCRC). The primary endpoints are safety, tolerability, and preliminary efficacy, as determined by disease control rate. The secondary endpoints include objective response rate, duration of response, progression-free survival, and overall survival.

Rottapharm Biotech’s clinical collaboration with Agenus offers a promising new combination therapy for patients with advanced pMMR/MSS mCRC where there is a high unmet need, and for a further range of potential applications in other immunotherapy-resistant tumors.

Rottapharm Biotech 

Rottapharm Biotech is a research company dedicated to the discovery and development of innovative drugs. It is located in Monza (Italy) The company expertise in research and development includes medicinal / computational chemistry for small molecules, a proprietary platform for the generation and selection of new monoclonal antibodies and the development of other biological drugs and advanced therapies, the validation of new molecular targets, the pharmacological, pharmacokinetic, toxicological and pharmaceutical characterization of new drug candidates; the design and conduct of innovative clinical trials. The company strategy is to develop its own pipeline independently and then seek partnerships with pharmaceutical companies, as well as investing in alliances on innovative projects of other biotech companies or university spin-offs.


Federica Girolami (Business Development, Scientific Liaison and Drug Safety Director)
Tel. +39 346 4131428

About Agenus

Agenus is a clinical-stage immuno-oncology company focused on the discovery and development of therapies that engage the body’s immune system to fight cancer. The Company’s vision is to expand the patient populations benefiting from cancer immunotherapy by pursuing combination approaches that leverage a broad repertoire of antibody therapeutics, adoptive cell therapies (through its affiliate MiNK Therapeutics), adjuvants, and proprietary cancer vaccine platforms. The Company is equipped with a suite of antibody discovery platforms and a state-of-the-art GMP manufacturing facility with the capacity to support clinical programs. Agenus is headquartered in Lexington, MA.

For more information, please visit and the Twitter handle @agenus_bio. Information that may be important to investors will be routinely posted on our website and Twitter.

Agenus Cautionary Statement Regarding Forward-Looking Statements

This press release contains forward-looking statements that are made pursuant to the safe harbor provisions of the federal securities laws, including statements regarding clinical development and regulatory plans and timelines, anticipated corporate milestones, new clinical data and program updates to be presented. These forward-looking statements are subject to risks and uncertainties that could cause actual results to differ materially. These risks and uncertainties include, among others, the factors described under the Risk Factors section of our most recent Quarterly Report on Form 10-Q or Annual Report on Form 10-K filed with the Securities and Exchange Commission. Agenus cautions investors not to place considerable reliance on the forward-looking statements contained in this release. These statements speak only as of the date of this press release, and Agenus undertakes no obligation to update or revise the statements, other than to the extent required by law. All forward-looking statements are expressly qualified in their entirety by this cautionary statement.


Agenus Inc.
Divya Vasudevan, PhD

Agenus Media Relations
Kimberly Ha
KKH Advisors