Mast Therapeutics begins enrolment for Phase II INABLE-TRAINING study of AIR001 to treat HFpEF


US-based biopharmaceutical company Mast Therapeutics has begun enrolment for its Phase II INABLE-TRAINING study of AIR001 to treat heart failure with preserved ejection fraction (HFpEF).

AIR001 is a sodium nitrite solution developed for intermittent inhalation via nebulisation. Nitrite is a direct vasodilator and can be recycled into in vivo to form nitric oxide (NO) that is independent of the classical NO synthase (NOS) pathway.

The NO formation results in several clinically beneficial effects such as the dilation of blood vessels and reduction of inflammation and undesirable cell growth.

Formation of NO from sodium nitrite is not dependent upon endothelial function and is expressed in the setting of tissue hypoxia and acidosis, conditions in which NOS activity is evident.

The Phase II randomised, double-blind, parallel-group and placebo-controlled Inorganic Nitrite to Amplify the Benefits and Tolerability of Exercise Training (INABLE-TRAINING) trial is being conducted to test the effect of inhaled AIR001 on chronic exercise training (ET) in subjects with HFpEF than placebo.

"There are now three Phase II studies actively enrolling patients to evaluate AIR001 for the treatment of HFpEF and we remain excited about its potential in this indication."

Mast Therapeutics CEO Brian Culley said: "There are now three Phase II studies actively enrolling patients to evaluate AIR001 for the treatment of HFpEF and we remain excited about its potential in this indication.

"Data from this and other studies will help guide our clinical and regulatory strategy in this area of significant unmet need.

"Currently, HFpEF affects approximately half of the more than five million people in the US diagnosed with heart failure and has no proven effective treatment."

The study is expected to enrol about 68 patients who will undergo 12 weeks of cardiac rehabilitation, including exercise training, and will receive either AIR001 or placebo inhalation solution during the training period.

It is firstly focused on determining the efficacy of inhaled AIR001 in addition to ET in improving exercise capacity and hemodynamic reserve in HFpEF.

Secondly, it will evaluate the ability of AIR001 in addition to ET in improving daily activity levels and quality of life (QOL) while reducing symptoms of effort intolerance during ET.