Fenoterol is a drug that has been used for the treatment of disease like asthma for many years. It is available in Canada in an inhaled form where it is called Berotec . Fenoterol stimulates receptors in the body called Beta Adrenergic Receptors and is therefore in a family of drugs called Beta Agonists. While one particular form of the drug, called a Racemic mixture has traditionally been used for asthma, multiple forms of the drug have now been produced and it is possible that using one of the newer forms of the drug will have benefits for people with heart failure.
Treatment for heart failure is a complex problem. It is a problem of the heart not pumping enough blood to meet the demands of the body and a number of changes that ultimately prove harmful in an attempt to compensate for this failure. Scientists have observed several effects of Fenoterol that may prove beneficial to people with heart failure. Use of the older Fenoterol (Racemic) mixture indicates that the drug causes the heart to pump more blood out to the rest of the body by increasing a person s heart rate but having little to no effect on their blood pressure. These effects provide a rationale for attempting to develop Fenoterol as a possible treatment for congestive heart failure. It is hoped that this new form of the drug will prove to have even more benefits.
However, the new form of the drug (called the R R form ) has not yet been tested in humans. Animal studies and scientific understanding of these types of mixtures suggest that it will little to no difference between it and the older Racemic form. To test this thinking and determine what doses should be used in future studies, we will conduct a Phase I, escalating dose study in healthy volunteers using the orally administered forms of the older Racemic mixture and newer R R form .
This study will consist of three groups of 6 people taking doses of the drug by mouth and then monitoring their heart rate, blood pressure, blood chemistry, genetic factors, and heart function. The first group will get a 2.5 mg dose of the R R form of the drug on one visit and then a 5 mg dose of the racemic mixture on the other visit. The second group will get a 5mg dose of the R R form on one of their visits and a 10mg dose of the Racemic mixture on the other. Finally, the third group will get a 10mg dose of the R R form on one visit and a 20mg dose of the Racemic mixture on the other. Also, blood will be collected at regular intervals to monitor levels of the drug, its rate of breakdown, changes in blood chemistry, and the testing of various genes. All research will be performed at the National Institute on Aging (NIA) Clinical Research Unit located on the 5th floor of Harbor Hospital in Baltimore, MD.
Testing the safety and breakdown of this drug and comparing it to the older Racemic form will be an important first step in its development as a new drug for heart failure.
The specific aims are:
1. A Phase 1 study in healthy volunteers to establish the body s absorption and breakdown of this new form of Fenoterol (R R form) in comparison with the older, established Racemic mixture.
2. To monitor the effects of the drug on heart rate, blood pressure, and cardiac structure and function after a person takes the drug.
Endpoint: This study will provide a safety assessment and will determine the pharmacokinetics and bioavailability of (R,R )- and racemic Fenoterol in healthy subjects. In addition, information will be gained about the pharmacodynamics of Fenoterol. This will provide information for future studies that will evaluate (R,R )-Fenoterol as a potential treatment for congestive heart failure.
