Cortex Pharmaceuticals, Inc. announced that it has received a Notice of Allowance from the US Patent and Trademark Office (USPTO) for a patent that protects the use of Ampakine molecules for the treatment or prevention of respiratory depression. This patent broadly covers all Ampakine molecules, including competitor compounds, and provides patent protection into 2027. The patent is licensed exclusively to Cortex from the University of Alberta, and is based on the pioneering research of Dr John Greer.

Dr Greer stated, “It is striking how well Ampakines enhance the activity of brain cells in the respiratory rhythm generator. This offers the potential to effectively counter respiratory depression caused by a host of factors ranging from opiate analgesics, anaesthetics through to pathological conditions. We are very encouraged by the pre-clinical and clinical data and continue to focus on this exciting opportunity to translate our basic neuroscience research to the clinic.”

Ampakine compounds have previously demonstrated proof-of-concept in the prevention of opiate-induced respiratory depression in both animal models and in a human clinical study. In these double-blind, placebo-controlled, cross-over clinical trials, baseline breathing rates were significantly depressed by the potent opiate, alfentanil. A single oral dose of the Ampakine, CX717 prevented alfentanil-induced respiratory depression without interfering with the desired analgesic effects of the opiate.

Earlier this year, Cortex reported results from a phase II a sleep lab study with its lead Ampakine molecule, CX1739 in subjects with moderate to severe sleep apnea. The results from this study suggested a potential opportunity for CX1739 in the treatment of central sleep apnea, which is often seen in heart failure patients and chronic opiate users. This same brain region, the respiratory rhythm generator, also plays a role in central sleep apnea, a form of central respiratory depression which occurs during sleep in approximately 30-40 per cent of heart failure patients.

“The presence of central sleep apnea in heart failure patients leads to a reduced heart function, which often leads to a reduced life span. Existing evidence suggests that treating sleep apnea can have long-term beneficial effects on these patients, in terms of heart function and quality of life,” stated Mark Varney, president and CEO of Cortex. “We are currently planning to test CX1739 for its ability to attenuate central sleep apnea in this patient population, and are eager to begin these studies.”

Cortex is a clinical-stage neuroscience company focused on the discovery, development and commercialization of a novel class of glutamate modulators called Ampakine compounds, which have been shown to enhance impaired breathing by stimulation of AMPA-type glutamate receptors in neurons in the brain stem.