Absorptive Clearance After Inhaled Osmotics in Cystic Fibrosis

This study has been completed.
Sponsor:
Information provided by (Responsible Party):
University of Pittsburgh
ClinicalTrials.gov Identifier:
NCT01223183
First received: October 14, 2010
Last updated: June 14, 2013
Last verified: June 2013
  Purpose

Blockage of the breathing tubes of the lungs by thick, sticky mucus is a major cause of lung problems for people with cystic fibrosis (CF). Many researchers now believe that people with CF absorb too much water from the insides of their lungs, and that the mucus in their lungs becomes so thick and sticky because there is not enough water in it. The investigators are trying to develop ways to measure how fast water is absorbed from the breathing tubes in the lung so that the investigators can more quickly test new medications that are being developed to fix this problem for CF patients. The investigators have already done studies showing that people with CF absorb a particular radioactive drug (Indium-111 DTPA or In-DTPA) from their lungs more quickly than people without CF. Now the investigators are trying to prove that the absorption of this drug is related to the absorption of water. The investigators measure the absorption of In-DTPA by delivering it in an aerosol (inhaled mist) along with another radioactive drug (Technetium 99m sulfur colloid). This other drug helps us measure how much material is cleared from the lungs in other ways (like coughing) without being absorbed. In this study, the investigators will measure how the absorption of In-DTPA is affected by inhaling isotonic saline and hypertonic saline (salt water), both of which the investigators know affect the absorption of water in the airways.


Condition Intervention Phase
Cystic Fibrosis
Drug: hypertonic saline (7%)
Drug: isotonic saline
Phase 1

Study Type: Interventional
Study Design: Intervention Model: Crossover Assignment
Masking: Open Label
Primary Purpose: Basic Science
Official Title: Absorptive Clearance After Inhaled Osmotics in Cystic Fibrosis

Resource links provided by NLM:


Further study details as provided by University of Pittsburgh:

Primary Outcome Measures:
  • Absorptive clearance rate [ Time Frame: two visits inside of 24 days ] [ Designated as safety issue: No ]
    The absoprtion rate of In-DTPA in the airways


Enrollment: 20
Study Start Date: September 2010
Study Completion Date: December 2012
Primary Completion Date: December 2012 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
Experimental: cystic fibrosis Drug: hypertonic saline (7%)
single treatment by inhalation
Drug: isotonic saline
single treatment by inhalation

Detailed Description:

There is a substantial need for new biomarkers in the study of cystic fibrosis (CF) lung disease. Conventional endpoints, such as rate of FEV1 decline, require prolonged trials and large sample sizes to demonstrate therapeutic efficacy. Ideally such biomarkers would provide a quantitative window to the most basic aspects of CF pathophysiology, allowing for the development and evaluation of therapies prior to large scale clinical trials. The basic defect of CF lung disease occurs in the airways where dysfunction of the cystic fibrosis transmembrane conductance regulator (CFTR) and epithelial sodium (ENaC) channels is thought to create an ionic gradient that causes excessive liquid absorption across the epithelium. This results in a dehydrated airway surface liquid (ASL) layer, defective mucociliary clearance, and an increased proclivity for infection and inflammation.

Aerosol-based methods have been developed to measure mucociliary clearance in the lung and used to demonstrate the efficacy of inhaled osmotic therapies. We have developed an aerosol technique to measure both mucociliary clearance and the absorptive clearance of a hydrophilic small molecule (Diethylene triamine pentaacetic acid - DTPA) in whole, central, and peripheral lung regions. We estimate DTPA absorption by delivering an aerosol containing both Indium 111 DTPA (In-DTPA) and Technetium 99m sulfur colloid (Tc-SC) to the airways. The clearance of each radiopharmaceutical is imaged independently and two separate clearance curves are calculated. In-DTPA is cleared through both absorption and mucociliary clearance while Tc-SC is cleared only through the mucociliary route. The difference between the clearance rates of the radiopharmaceuticals provides an estimate of DTPA absorption rate.

Our previous studies have demonstrated that absorption of Indium-111 labeled DTPA occurs at a higher rate in central (airway dominated) lung zones of CF subjects compared to controls (42 vs. 32 %/hr, CF n= 9, control n=10, p=0.03). We believe that this increased DTPA absorption is being caused by the increased liquid absorption occurring in these airways, however there are other potential causes such as increase in tight junction permeability or epithelial denuding.

In this study we propose to measure DTPA absorption after the delivery of interventions known to affect liquid absorption in the airways to see if changes in DTPA absorption mirror the changes in liquid absorption known to be caused by the interventions.

  Eligibility

Ages Eligible for Study:   18 Years and older
Genders Eligible for Study:   Both
Accepts Healthy Volunteers:   No
Criteria

Inclusion Criteria:

  • age ≥ 18 years
  • diagnosis of cystic fibrosis as determined by sweat test or genotype and clinical symptoms
  • clinically stable as determined by the investigator (pulmonologist)

Exclusion Criteria:

  • intolerant to hypertonic saline.
  • FEV1%p <40% of predicted
  • nursing mother
  • positive urine pregnancy test
  • unwilling to stop hypertonic saline therapy for 72 hours prior to each test day
  • cigarette smoker (regular smoking within 6 months of study)
  Contacts and Locations
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Please refer to this study by its ClinicalTrials.gov identifier: NCT01223183

Locations
United States, Pennsylvania
University of Pittsburgh
Pittsburgh, Pennsylvania, United States, 15213
Sponsors and Collaborators
University of Pittsburgh
  More Information

Additional Information:
Publications:
Responsible Party: University of Pittsburgh
ClinicalTrials.gov Identifier: NCT01223183     History of Changes
Other Study ID Numbers: PRO09080375
Study First Received: October 14, 2010
Last Updated: June 14, 2013
Health Authority: United States: Institutional Review Board

Keywords provided by University of Pittsburgh:
cystic fibrosis
nuclear medicine
aerosol
nebulizer

Additional relevant MeSH terms:
Cystic Fibrosis
Fibrosis
Pancreatic Diseases
Digestive System Diseases
Lung Diseases
Respiratory Tract Diseases
Genetic Diseases, Inborn
Infant, Newborn, Diseases
Pathologic Processes

ClinicalTrials.gov processed this record on August 18, 2014