Breath test for detection of drug metabolism

• US 5,962,335 A
• Filed: 01/03/1997
• Issued: 10/05/1999
• Est. Priority Date: 01/03/1997
• Status: Expired due to Term

• Current Assignee: Exalenz Bioscience, Ltd. (Otsuka Holdings Company Limited)
• Original Assignee: Oridion Medical Ltd (Medtronic Plc)
• Inventors: Katzman, Daniel E.
• Primary Examiner(s): WALLENHORST, MAUREEN
• Application Number:
  US08/778,589
• Time in Patent Office: 1,005 Days
• Field of Search: 436/56, 436/106, 436/113, 436/127, 436/133, 436/173, 436/175, 436/181, 436/900, 436/901, 422/61, 422/83, 422/84, 73/23.3
• US Class Current: 436/181
• CPC Class Codes: A61K 47/6949 inclusion complexes, e.g. clathrates, cavitates or fullerenes
• CPC Class Codes: A61K 51/1206 Administration of radioactive gases, aerosols or breath tests
• CPC Class Codes: B82Y 5/00 Nanobiotechnology or nanomedicine, e.g. protein engineering or drug delivery
• CPC Class Codes: Y10S 436/90 Breath testing
• CPC Class Codes: Y10T 436/13 Tracers or tags
• CPC Class Codes: Y10T 436/204998 Inorganic carbon compounds
• CPC Class Codes: Y10T 436/24 Nuclear magnetic resonance, electron spin resonance or other spin effects or mass spectrometry
• CPC Class Codes: Y10T 436/25875 Gaseous sample or with change of physical state

Abstract

A breath test for determining the rate of metabolism of a drug is described. First, a safe and effective amount of the drug, preferably appropriately labelled and most preferably isotopically-labelled, is administered to a subject. After a suitable time period, the exhaled breath of the subject is analyzed to determine the concentration of a metabolite. The concentration of the metabolite is then used to determine the rate of metabolism of the drug. A breath test kit is also described. Such a breath test kit would include an item or items necessary for performing at least one of the methods of determining the rate of metabolism of a drug in a subject. For example, such a breath test kit could include an isotopically-labelled drug to be administered to the subject.

Claims

1. A method for determining a therapeutic dosage regimen of a drug administered to a subject comprising the steps of:

a. labeling a drug sought to be administered therapeutically to a subject with a non-radioactive isotope having a range of natural abundance and being detectable in a metabolite of said drug;

b. prior to administration of said drug to a subject, measuring a first concentration of said non-radioactive isotope in the subject'"'"'s breath;

c. following said measuring step, administering said drug labeled with said non-radioactive isotope to the subject;

d. following the administering step, measuring a second concentration of said non-radioactive isotope in the subject'"'"'s breath, at least one of said first and second concentrations being within the range of natural abundance of the isotope; and

e. employing the difference between said first and second concentrations to provide information as to a therapeutically acceptable dosage regimen of said drug based on metabolization of said drug by the subject.

2. A method according to claim 1 further comprising administering said drug to said subject in a therapeutically acceptable dosage regimen confirmed using said employing step e.

3. A method according to claim 1 wherein said measuring comprises the use of a measuring instrument selected from the group consisting of an infrared spectrometer and a mass spectrometer.

4. A method according to claim 1 wherein said non-radiactive isotope is carbon 13.