ATPace™

ATPace (adenosine triphosphate injection) is a proposed product for the acute treatment and diagnosis of certain cardiac arrhythmias (abnormal heart rate). These include the termination of paroxysmal supraventricular tachycardia (PSVT), a rapid regular heart rate originating in the atria. ATPace is also being developed to diagnose bradycardia (slow heart rate), which is one of the main causes of fainting.

Therapeutic Indication:

ATPace, a stable liquid formulation of adenosine 5’-triphosphate (ATP) for intravenous injection, is an investigational drug for the acute termination of PSVT. The bradycardic effect of ATP, in particular its blockade of atrio-ventricular nodal conduction, has been shown in numerous published clinical studies to safely and effectively terminate re-entrant PSVT involving the atrio-ventricular node. Design of a pivotal Phase 3 clinical trial for ATPace in PSVT is in the planning stage.

PSVT, one of the most common cardiac arrhythmias, is a rapid, regular heart rate originating in the atria. It has been estimated that there are 89,000 new cases of PSVT per year and approximately 570,000 persons with PSVT in the United States alone.

Currently, adenosine is the only approved treatment for PSVT in the United States. Duska believes that the initial dose of ATPace will be significantly more efficacious than the initial labeled dose of adenosine in terminating PSVT. While both ATP and adenosine inhibit atrio-ventricular nodal conduction, ATP is believed to have dual inhibitory action; one mediated by adenosine, the product of its rapid enzymatic degradation, and the other a triggered vagal reflex. Vagal maneuvers aimed at enhancing vagal tone to the heart, and thereby suppressing atrio-ventricular nodal conduction, have been clinically used to terminate tachycardia. Injectable formulations of ATP have been approved in Europe for over 50 years as safe and efficacious treatments for PSVT.

Duska has established its own safety database for ATPace, which was obtained in its Phase 1 and 2 clinical trials, and has obtained more than 1,000 patients records from other clinical trials. On April 16, 2008, Duska met with the FDA and confirmed that a New Drug Application under section 505(b)(2) would be the appropriate regulatory pathway for filing an ATPace marketing application for the acute treatment of PSVT. Duska is in the process of modifying the proposed Phase 3 clinical trial in accordance with the FDA’s comments and plans to submit a revised protocol to the FDA for Special Protocol Assessment procedure approval. Duska intends to initiate a single, prospective, placebo-controlled, and randomized trial in patients presenting to the emergency room with PSVT to demonstrate ATPace’s clinical safety and efficacy. Upon successful completion, Duska would intend to file a New Drug Application under section 505(b)(2).

Legend: ATP activates P2X2/3 receptors on vagal sensory nerve terminals in the heart. These nerve terminals are believed to play a mechanistic role in certain types of fainting.

Diagnostic Indication:

Duska is pursuing the development of ATPace to diagnose fainting due to bradycardia (abnormally slow heart rate). Duska believes that the bradycardic effect of ATPace is much more pronounced in selected groups of patients with fainting of unknown origin or suspected neurally-mediated fainting. ATPace injection conducted in a doctor’s office in about an hour should identify patients with bradycardic fainting who could benefit from cardiac pacemaker therapy. Duska anticipates that the ATPace diagnostic test will be quick, safe, cost-effective and convenient when compared to other current diagnostic alternatives. The only approved diagnostic test that can determine the potential benefits of cardiac pacemaker therapy in patients with recurrent fainting is the Insertable Loop Recorder (ILR), a device that is implanted in the patient’s chest for several months. ILR requires 2 surgeries resulting in pain to the patient and high cost and may not yield any conclusive results after several months. ATPace has the potential to benefit a significant number of patients whose fainting is currently misdiagnosed and mistreated.

Duska Therapeutics

info@duskatherapeutics.com

At the heart of cardiovascular medicine