Lantheus Medical Imaging, a provider in diagnostic medical imaging, has presented preliminary Phase 2 data describing the methodology used to define an imaging protocol for a one-day rest-stress myocardial perfusion imaging test using its investigational PET imaging agent flurpiridaz F 18 injection.

Flurpiridaz F 18 injection is in development for use with Positron Emission Tomography (PET) for myocardial perfusion imaging (MPI) to detect coronary artery disease.

Data suggested that the uptake properties of flurpiridaz F 18 injection make it possible to allow for a relatively low dosing ratio and a delay of between 30 minutes and one hour between rest and stress injections, depending on the mode of stress used.

Lantheus, together with its partner in the method development, Cardiovascular Imaging Technologies of Kansas City, developed a technique to determine the dependence of the rest-to-stress dosing ratio in order to identify the minimum delay between the two injections for a one-day rest-stress test.

In evaluating the maximum residual contribution of the imaging agent initially used in the rest study to the subsequent stress image which did not produce a meaningful change in the reader’s perception of the stress image, it was determined for stress induced by adenosine (a pharmacological stress agent) that a minimum dosing ratio of 2.0 (twice as much imaging agent used in stress as compared to rest) was required with a 30 minute delay between injections.

Dana Washburn, vice president of clinical development and medical affairs at Lantheus Medical Imaging, said: “Using this novel approach, we expect to validate a protocol that fits into current clinical practice and that can be administered at the lowest possible dose for patients undergoing a same-day rest-stress test with flurpiridaz F 18 injection.

“We developed this novel methodology to define the rest and stress doses as well as the optimal delay between the two doses without having to involve a large number of patients.”