Circle Pharma, a clinical-stage biopharmaceutical company focused on macrocycle therapeutics, has received FDA Orphan Drug Designation for CID-078 in the treatment of small cell lung cancer (SCLC). The designation recognizes the significant unmet medical need in this aggressive cancer type and provides regulatory incentives to accelerate drug development.
Addressing an Aggressive Cancer with Limited Treatment Options
Small cell lung cancer represents a particularly challenging malignancy, accounting for approximately 13-15% of all lung cancer cases and demonstrating strong links to tobacco exposure. The disease is characterized by its highly aggressive nature, high recurrence rate, and poor overall prognosis. While newer therapies have shown some improvements in overall survival, most patients continue to experience rapid disease progression.
"The Orphan Drug Designation from the FDA underscores both the seriousness of small cell lung cancer and the lack of effective treatment options," said Michael C. Cox, PharmD, MHSc, BCOP, SVP, and head of early development at Circle Pharma. "We are committed to accelerating the clinical development of CID-078 to offer new hope for patients who face limited therapeutic choices."
Regulatory Benefits and Development Incentives
The FDA's Orphan Drug Designation program targets rare diseases or conditions affecting fewer than 200,000 people in the United States. This designation provides several significant development incentives, including seven years of market exclusivity upon regulatory approval, tax credits for qualified clinical trial costs, and eligibility to apply for FDA-administered research grants.
Novel Mechanism of Action
CID-078 represents a novel approach to cancer treatment as an orally bioavailable macrocycle with dual cyclin A and B RxL inhibitory activity. The drug selectively targets tumor cells with oncogenic alterations that cause cell cycle dysregulation. In biochemical and cellular studies, Circle Pharma's cyclin A/B RxL inhibitors have demonstrated the ability to potently and selectively disrupt protein-to-protein interactions between cyclins A and B and their key substrates and modulators, including E2F (a substrate of cyclin A) and Myt1 (a modulator of cyclin B).
Preclinical studies have shown promising results, with these cyclin A/B RxL inhibitors demonstrating the ability to cause single-agent tumor regressions in multiple in vivo models.
Current Clinical Development
Circle Pharma has initiated a Phase 1 clinical trial (NCT06577987) of CID-078 to evaluate its safety, tolerability, pharmacokinetics, and early signs of anti-tumor activity in patients with advanced solid tumors, including SCLC. The multi-center trial is currently enrolling patients.
Company's Macrocycle Platform
South San Francisco-based Circle Pharma leverages its proprietary MXMO™ platform to overcome key challenges in macrocycle drug development. The platform enables the creation of intrinsically cell-permeable and orally bioavailable therapies for historically undruggable targets. The company's pipeline focuses on targeting cyclins, key regulators of the cell cycle that drive many cancers, with CID-078 serving as the lead program in their cyclin-targeting approach.
