Circle Pharma Appoints Rajinder Singh, PhD as its Chief Science Officer

SOUTH SAN FRANCISCO, Calif.--()--Circle Pharma, Inc. has appointed Rajinder Singh, PhD as its Chief Science Officer. Dr. Singh will oversee Circle’s scientific work to develop macrocycle therapeutics against intractable cancer targets.

Dr. Singh has 25 years of experience in drug discovery and development, spanning small molecules, peptides and peptoids. He most recently served as Senior Vice President of Research and Pharmaceutics at ChemoCentryx and earlier in his career had senior roles at Rigel, Inc. and Chiron. He was awarded a doctorate in Organic chemistry from the University of Oxford where he studied under Prof. Sir Jack Baldwin, and subsequently undertook a postdoctoral research fellowship at Eli Lilly & Company.

“We are delighted to have Raj join the Circle team.” said David J. Earp, J.D., Ph.D., Circle’s President and CEO. “Raj brings deep experience in therapeutics research and development across chemistry, biology, pharmacology and pharmaceutics. He has built and led teams that have advanced multiple programs from discovery through pre-clinical optimization, and from Phase 1 to pivotal clinical studies. Raj is one of the inventors of Syk kinase inhibitor Tavalisse (fostamatinib) and most recently has supported the NDA submission for C5aR inhibitor avacopan. I am very much looking forward to working with Raj to bring Circle’s therapies to patients.”

“We would also like to express our deep appreciation to Dr. David Spellmeyer, who has served as Circle’s interim CSO since October 2017. With David’s scientific guidance and leadership, we have significantly advanced our macrocycle drug discovery platform and our cyclin programs. David will continue as an advisor to Circle, focusing on informatics and computational chemistry.”

About Circle Pharma, Inc.

Circle is developing a new paradigm for macrocycle drug discovery based on rational design and synthetic chemistry. Circle’s technology facilitates the design and synthesis of intrinsically cell-permeable macrocycles that can address both intra- and extra-cellular therapeutic targets, and can be delivered by oral administration. Circle’s macrocycle development platform is applicable across a wide range of serious diseases; the company is initially focusing its development efforts on intracellular protein-protein interactions that are key drivers in cancer. Its lead programs target cyclins A and E, which are part of the regulatory machinery that controls the progression of cells through the cell growth and division cycle. Inhibition of Cyclin A has been shown to be synthetically lethal in cancers driven by mutations in the Rb pathway. Cyclin E upregulation is associated with resistance to drugs that target cdk4/6 activity and is also found across several cancer types.

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David Earp

Release Summary

Rajinder Singh, PhD, has been appointed as Circle Pharma's Chief Science Officer, bringing 25 years of experience in drug discovery and development.


David Earp