F-star Therapeutics Announces Collaboration with MSD to Evaluate FS120 in Combination with KEYTRUDA

F-star Therapeutics, Inc. (NASDAQ: FSTX), a clinical-stage biopharmaceutical company dedicated to developing next generation bispecific immunotherapies to transform the lives of patients with cancer, today announced that it has entered into a clinical trial collaboration and supply agreement with MSD (Merck & Co., Inc., Kenilworth, NJ, USA), to evaluate the combination of FS120, F-star’s first-in-class dual-agonist tetravalent bispecific antibody targeting CD137 and OX40, with KEYTRUDA® (pembrolizumab), MSD’s anti-PD-1 therapy. 

Under the terms of the agreement, MSD will supply KEYTRUDA for a combination arm that will be included in the adaptive Phase 1 clinical protocol of FS120, sponsored by F-star, that was initiated in December of 2020. FS120 is currently being explored as a monotherapy in dose escalation (NCT04648202), including the evaluation of pharmacokinetics and pharmacodynamics in patients with advanced cancer.  FS120 will also be evaluated in combination with KEYTRUDA, with the potential for early demonstration of clinical activity in specific tumor subtypes.  F-star expects to provide a progress update on the FS120 monotherapy accelerated dose titration cohorts later this year and plans to initiate the KEYTRUDA combination cohorts in the second half of 2022, following completion of the FS120 monotherapy dose escalation.

Louis Kayitalire, Chief Medical Officer of F-star, said “This partnership with MSD represents a significant milestone for our FS120 Phase 1 trial as F-star looks to transform the care of those patients with cancer who have limited treatment options. FS120 offers an opportunity to improve upon current treatment paradigms, either as a monotherapy or in combination. In preclinical studies, FS120 has demonstrated strong additive effects in combination with PD-1 monoclonal antibodies. We look forward to working with MSD to evaluate the potential combined effect of FS120 with KEYTRUDA as we strive to improve the quality of life and duration of response for patients with difficult to treat cancers.” 

About FS120 
FS120 is a first-in-class dual-agonist tetravalent bispecific antibody targeting CD137 (4-1BB, TNFRSF9) and OX40 (CD134, TNFRSF4). FS120 has the potential to show activity in "cold" tumors and improve outcomes of existing immunotherapies by simultaneously agonizing CD137 and OX40. These two receptors are part of the Tumor Necrosis Factor Receptor family ("TNFRSF") and are widely expressed on activated T cells and NK cells in tumors. Many TNFRSF-targeting antibodies require crosslinking via Fcγ receptors ("FcγRs") to show activity, but this engagement can limit their clinical activity and lead to significant toxicity. FS120 has been designed to be FcγR-null and instead uses bispecific crosslinking to drive robust receptor clustering and activation, without engaging the FcγR. FS120 preclinical data demonstrated delays in tumor growth, activation and proliferation of CD4⁺ and CD8⁺ T cells, and synergies with PD-1 monoclonal antibodies and chemotherapies. 

About F-star Therapeutics, Inc. 
F-star is a clinical-stage biopharmaceutical company developing tetravalent bispecific antibodies for a paradigm shift in cancer therapy. By developing medicines that seek to block tumor immune evasion, the Company’s goal is to offer patients greater and more durable benefits than current immuno-oncology treatments. Through its proprietary tetravalent, bispecific natural antibody (mAb²™) format, F-star’s mission is to generate highly differentiated best-in-class drug candidates with monoclonal antibody-like manufacturability. For more information visit www.f-star.com and follow us on LinkedIn and Twitter.