A Comparison of Technegas and Xenon-133 Planar Lung Imaging in Subjects Referred for Ventilation Scintigraphy

This is a Phase 3 within-subject non-inferiority trial of Technegas ventilation imaging
compared to Xenon-133 (Xe-133) ventilation imaging to demonstrate the non-inferiority of
Technegas compared to Xe-133 ventilation studies with respect to subject pulmonary
ventilatory distribution. Subjects will undergo site-specific standard of care (SOC) Xe-133
imaging per medical needs followed by Technegas ventilation imaging per study protocol.
Primary assessments of efficacy will be based on three blinded readers' assessments of the
Technegas and Xe-133 ventilation images in independent reading sessions.

Inclusion Criteria:

- Male or female subject at least 18 years of age.

- Subject is a candidate for ventilation imaging.

- Subject must be willing and able to provide informed consent.

- Subject must be stable and able to undergo Xe-133 planar imaging and Technegas planar
imaging.

- Subject must be willing and agree to complete study procedures.

- Subject is using adequate birth control, if female and fertile. Adequate birth control
is defined as surgical sterilization, hormone contraceptive use or intrauterine device
(IUD).

- Female subject of child-bearing potential has a negative urine or serum pregnancy
test.

- Subject has had or is scheduled to have a chest X-ray within 24 hours prior to the
investigational imaging study.

Exclusion Criteria:

- Subject has been administered any other radiopharmaceutical within a timeframe that
might cause interference with study imaging.

- Subject is a pregnant or lactating female.

- Subject has received Technegas in the past.

- Subject has received an investigational drug within 30 days prior to dosing.

- Subject is hemodynamically unstable.