CS1 increases the production of t-PA

The drug candidate CS1 is a new advanced reformulation of valproic acid (VPA) and acts as an epigenetic modulator with anti-thrombotic, anti-inflammatory, anti-fibrotic, and pressure-relieving properties. CS1 is being developed as a treatment for the rare disease pulmonary arterial hypertension (PAH) with the aim to offer patients a better, disease-modifying drug.

CS1’s epigenetic mechanism is expressed through HDAC (histone deacetylase) inhibition and brings a novel treatment approach to cardiovascular disease. The current body of evidence supporting CS1’s properties has been provided through a successful Phase I study, but also through in vitro studies, animal models, human physiological data, and independent epidemiology studies. In preclinical studies, CS1 showed an improvement in the endogenous fibrinolytic system by supporting thrombolysis only at the site of the injury with few side effects, especially no bleedings. With the clinical phase I study, CS1 demonstrated good safety and tolerability, robust reduction of PAI-1 and no problems with bleeding.

Combined, CS1 shows strong promise for a four-fold efficacy:

• Anti-thrombotic
• Anti-inflammatory
• Anti-fibrotic
• Pulmonary pressure-relieving properties

 

Clinical phase II program

A clinical phase IIa study with CS1 in rare disease pulmonary arterial hypertension (PAH) was initiated in 2021. This Phase II study intends to evaluate drug candidate CS1’s safety, tolerability, dose and exploratory efficacy in patients with the rare disease PAH. The primary endpoint is safety and tolerability. All standard efficacy endpoints for this patient group will be explored as well as a validated risk score. Cereno anticipates that dosing for later studies will be informed by the continuous pulmonary pressure readings derived from global partner Abbott’s CardioMEMS HF System. 

The clinical development program for CS1 in PAH is anchored in the Orphan Drug Designation (ODD) that was granted by the US Food and Drug Administration (FDA) in March 2020. The US FDA grants orphan drug designations to entice the development of products that are intended for the treatment of rare diseases that affect fewer than 200,000 people in the US. Several incentives are associated with ODDs to facilitate the drug development for rare diseases, such as seven years of market exclusivity in the US if the drug is approved, FDA assistance in clinical trial design, and tax credits for qualified clinical trial costs. Through the granted ODD request, the FDA has indicated that they believe that CS1 has the potential to provide significant benefit to patients suffering from PAH.

Cereno’s development program for CS1 in thrombotic indication VTE/SPAF is deferred to follow after the Phase II study program in PAH.