By Ann Neuer
May 4, 2009 | Acquiring medical images is an art form, especially when those images serve as endpoints for clinical trials. So says Kenneth Faulkner, VP of medical imaging for Perceptive Informatics, a subsidiary of PAREXEL. Proper acquisition of images is gaining importance as pharmaceutical and biotechnology sponsors embrace imaging more frequently in the earlier phases of clinical development as a tool for faster separation of the more promising compounds from less hopeful ones.
To expand the role of early imaging in clinical trials, sponsors are engaging multiple investigative sites, and are recognizing the need for those sites to acquire images in a uniform manner. “In a multi-center regulated environment, the most important thing is consistency. We need to have all of the sites doing things the same way so we can guarantee that any difference in response is due to the drug, and not due to differences in procedure,” Faulkner says.
To facilitate greater use of standardized imaging practices in early clinical trials, Perceptive (along with its PAREXEL parent) has established a dedicated early phase investigational unit offering streamlined image collection, comprehensive image management, and independent image interpretation by industry experts. The company uses its network of sites and provides them with the necessary training to acquire images uniformly in compliance with protocol. In addition, Perceptive is working actively with the Society for Nuclear Medicine as well as other organizations to establish guidelines for the use of exploratory imaging endpoints, such as positron emission tomography (PET) and functional magnetic resonance imaging (fMRI), in early phase multi-center studies. Standardized training and procedures are critical as sites can acquire images in various ways, making the task of consistent image compilation and interpretation nearly impossible.
As an added quality control measure, sites are tested periodically throughout studies for competency. The company maintains early phase testing sites in the United States, Latin America, South Africa, Europe, and Asia.
The push toward earlier imaging comes with broader use of techniques such as PET, fMRI, and single-photon emission computed tomography (SPECT). Traditionally, these techniques have been the domain of academic medical centers where they have been used in small studies involving a handful of sites, often as few as one or two. As Faulkner explains, “Expanding the use of PET beyond the realm of the academic medical center has been difficult because of challenges involved in standardizing how procedures are done.”
Consistent imaging practices yield results that are increasingly recognized for the value they bring to the clinical development process. First, they can help sponsors make better and faster GO/NO-GO decisions by detecting early clues of safety and efficacy. Taking this step sooner, rather than waiting until later phases to introduce imaging, cuts time and expense from clinical development timelines. Also, reliable imaging results can do more than identify endpoints that comply with guidelines for regulatory submission. They can actually provide a marketing advantage. “To go to market, you may need other endpoints that are not accepted for regulatory approval. For example, a regulatory endpoint for rheumatoid arthritis might be images of painful swollen joints. But there may be early signals using magnetic resonance imaging (MRI), x-ray, even ultrasound that are not for regulatory submission but can detect when that disease is starting before it progresses to the point of irreparable damage,” Faulkner comments.
By the time the patient seeks help for swollen joints, the disease has already progressed to the point that clinicians can do little more than relieve their pain. If it is detected earlier, there might be a chance of reversing the damage. It is this broader use of imaging as a diagnostic tool that is often rooted in clinical trials and eventually reaches patients the world over as it becomes part of routine medical practice.