Sanofi to evaluate the safety and efficacy of novel investigational candidate THOR-707 and KEYTRUDA® (pembrolizumab) in pursuit of establishing a new treatment option in oncology

October 29, 2020
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Sanofi to evaluate the safety and efficacy of novel investigational candidate THOR-707 and KEYTRUDA® (pembrolizumab) in pursuit of establishing a new treatment option in oncology

*THOR-707 (SAR444245) is a non-alpha IL-2 candidate with a best-in-class profile currently being evaluated in Phase 1 trials for the treatment of solid tumors

PARIS – October 29, 2020 – Sanofi has entered into an agreement with Merck & Co., Inc., Kenilworth, NJ, USA (known as MSD outside the U.S. and Canada) to conduct a Phase 2 clinical trial to evaluate the safety, pharmacokinetics, and preliminary efficacy of THOR-707, a highly differentiated non-alpha IL-2 candidate with a best-in-class profile, combined with or in sequenced administration with MSD’s KEYTRUDA® (pembrolizumab) in patients with various cancers.

Under the agreement, Sanofi will sponsor the clinical trials while MSD will provide KEYTRUDA.

“We believe that THOR-707 has the potential to become a foundation of the next generation of immuno-oncology therapies,” said Peter Adamson, Global Head, Oncology Development and Pediatric Innovation, Sanofi. “This collaboration with MSD will enable us to explore whether THOR-707 can increase and expand the effectiveness of KEYTRUDA and improve the outcomes for patients with cancer.”

THOR-707 is currently being evaluated by Sanofi in an ongoing Phase 1 open-label, multi-center, dose escalation and expansion trial.  This study is designed to evaluate the safety and tolerability of THOR-707, and to determine its recommended Phase 2 dose alone and in combination with anti-PD-1 and anti-EGFR antibodies.

In addition to testing THOR-707 in combination with KEYTRUDA, Sanofi is separately evaluating the activity of this novel biologic in combination with other anti-PD-1 antibodies, including Libtayo® (cemiplimab-rwlc) and with anti-EGFR and anti-CD38 antibodies for various types of cancer tumors.

THOR-707 demonstrated in preclinical studies the ability to induce the expansion of CD8+T-cells resulting in anti-tumor effects both as single agent as well as in combination with an anti-PD1 mAb.

It is the first molecule from the Synthorin platform, Sanofi’s unique expanded genetic alphabet platform, which has the potential to create a new generation of precision medicines for oncology and autoimmune disease.

About THOR-707

THOR-707 has the potential to be a best-in-class IL-2 therapeutic for the treatment of many types of malignancies and may demonstrate improved pharmacology allowing for less frequent dosing. In pre-clinical experiments, THOR-707 shows striking synergy with anti-PD-1 therapeutics.

It is a precisely PEGylated engineered version of interleukin-2 (IL-2), where the PEG chain is attached at a location on IL-2 that prevents it from binding to immune receptors that cause drug toxicities (IL-2R-alpha, CD25) while preserving binding to immune receptors that selectively expand tumor-killing T effector and Natural Killer (NK) cells without the immunosuppressive effects of regulatory T cells or vascular leak syndrome (VLS) inducing eosinophils.

Editor’s Note: As discussed at Sanofi’s R&D Day in June, full Phase 1 results for THOR-707 and the recommended Phase 2 dose are expected by 2021.


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