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Circle Pharma

Category: AI in Healthcare

Circle Pharma is a clinical-stage biopharmaceutical company developing orally bioavailable, cell-permeable macrocyclic peptide therapeutics targeting intracellular protein-protein interactions for cancer and serious illnesses. Circle Pharma was founded in 2014. The company is led by David J. Earp. Based in South San Francisco, USA. Team size: 51-100. Total funding raised: $210.75M. Latest round: Series D. Key investors include The Column Group, Pfizer, Mission Bay Capital, ShangPharma Innovation, Nextech Invest, Euclidean Capital, Eli Lilly and Company.

Founded
2014
Headquarters
South San Francisco, USA
Team size
51-100
Total funding
$210.75M

Value proposition

Developing potent, selective, orally bioavailable macrocyclic therapies to drug traditionally undruggable intracellular protein interactions.

Products and solutions

CID-078 (Oral Cyclin A/B RxL Inhibitor) — Phase 1 clinical trials, CID-165 (Oral Cyclin D1 RxL Inhibitor) — development candidate nominated Dec 2025, Preclinical programs targeting Cyclin E1 and other oncology targets

Unique value

Ability to design macrocycles with drug-like properties including oral bioavailability and cell permeability, enabling targeting of intracellular proteins previously inaccessible to drugs.

Target customer

Pharmaceutical companies and patients with various cancers including solid tumors.

Industries served

Biotechnology, Pharmaceuticals, Oncology

Technology advantage

Proprietary computational and synthetic chemistry platform MXMO for rational design of macrocycles with high affinity and drug-like properties for intracellular targets.

How they differentiate

Proprietary MXMO platform enabling design of cell-permeable macrocycles targeting difficult intracellular protein interactions, differentiating from competitors focusing on other modalities.

Main competitors

Vividion Therapeutics, Bicycle Therapeutics, PeptiDream

Key partnerships

Pfizer Inc. – collaboration and investor, ShangPharma Innovation – investor, Mission Bay Capital – investor, Boehringer Ingelheim – research collaboration and license agreement (Oct 2024, up to $607M), Eli Lilly and Company – AI/ML platform agreement via Lilly TuneLab (Sept 2025)

Notable customers

Strategic collaboration with Boehringer Ingelheim announced October 2024 for cyclin inhibitor co-development valued up to $607M., Agreement with Eli Lilly and Company (Sept 2025) to use Lilly TuneLab AI/ML platform to enhance MXMO drug discovery capabilities.

Major milestones

Closed $90M Series D financing in September 2024., Received FDA Orphan Drug Designation for CID-078 in Small Cell Lung Cancer., Initiated Phase 1 clinical trial for CID-078 in solid tumors., Selected CID-078 as first clinical candidate in July 2023., Announced collaboration with Boehringer Ingelheim (Oct 2024) valued up to $607M., Agreement with Lilly to use TuneLab AI/ML platform (Sept 2025)., Nominated CID-165, first-in-class oral cyclin D1 RxL inhibitor, as development candidate (Dec 2025)., Appointed Anne E. Borgman, M.D. as Chief Medical Officer (Dec 2025).

Growth metrics

Private company with undisclosed revenue and user metrics.

Market positioning

Clinical-stage innovator in macrocycle drug discovery focused on challenging oncology targets.

Geographic focus

Based in South San Francisco with global clinical and partnership focus.

Patents and IP

Robust IP portfolio covering platform technology, novel macrocycles, and clinical candidates; protected by dedicated IP leadership.

About David J. Earp

Previously held various roles at Geron Corporation including Chief Patent Counsel, Chief Legal Officer and Senior Vice President of Corporate Transactions. Earlier in his career, was a partner at the intellectual property law firm Klarquist, LLP. Holds a Ph.D. in Biochemistry and Molecular Biology from the University of Cambridge and a J.D. (magna cum laude) from Northwestern School of Law of Lewis and Clark College.

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