Despite recent advances in molecular medicine, physicians are still in the dark about many diseases, gleaning clues to a therapy’s effectiveness only by studying changes in symptoms. Even as doctors seek the best treatment, patients may deteriorate. At Yale’s new Positron Emission Tomography (PET) Center, researchers hope to bring light into this darkness by discovering novel diagnostic tools for otherwise hidden molecular abnormalities and speeding development of new medications.
PET imaging, said George Mills, M.D., director of the Division of Medical Imaging and Radiopharmaceutical Drug Products at the Food and Drug Administration’s Center for Drug Evaluation and Research, is “the essential foundation” of the agency’s efforts to modernize the process of developing new medicines. Mills spoke at the January 18 opening ceremony for the new 22,000-square-foot facility, located at 801 Howard Avenue.
PET is a noninvasive imaging technique that scans for minute amounts of radioactive material—radiotracers—that have been injected into a patient’s body to bind to specific organ sites, providing images of molecular function. Researchers and clinicians use this information to study changes in organ function as a result of disease or in response to treatment. The radiotracer can also label a drug to determine whether and how much of the compound has reached its target. Labeling enables researchers to study the safety and efficacy of different dose levels and identify biological markers of disease that can aid in diagnosis.
“The work we do here will build the knowledge we need to develop diagnostic imaging agents coupled to therapy,” said J. James Frost, M.D., Ph.D., professor of diagnostic radiology and psychiatry, chief of nuclear medicine at Yale-New Haven Hospital and director of the PET Center. Joining Frost as co-directors are lead physicist Richard E. Carson, Ph.D., professor of diagnostic radiology and biomedical engineering; and lead radiochemist Yu-Shin Ding, Ph.D., professor of diagnostic radiology. Completing the senior faculty team is Henry Huang, Ph.D., a radiochemist and associate professor of diagnostic radiology.
The development of the center was made possible, in part, by Pfizer, the pharmaceutical company, which contributed $5 million to establish it and provides $2 million annually to support PET imaging studies of mutual research interest to both parties. Most research at the center will be supported by federal grants. The company has already used the PET facilities to study a small group of patients to determine how much of a new drug for depression would be required to reach its target in the brain, and how much would generate unacceptable side effects, said Diane K. Jorkasky, M.D., Pfizer’s vice president of clinical pharmacology.
Researchers are usually required to give dosages that escalate over several months to large numbers of patients to establish the safest and most effective dose of a drug. “If we are able to avoid the need to do large-scale clinical studies like that, we’ll be saving tons of money and time, and most important, we won’t expose patients needlessly to a drug that may not have any benefit,” said Jorkasky.
Frost said the center will serve as a core facility for the entire School of Medicine. Some biomarkers discovered in the course of research projects with Pfizer or other companies will be available for faculty research projects.
Along with cardiology and oncology, other major areas of focus are Alzheimer’s disease, schizophrenia, depression, obesity, post traumatic stress disorder and other conditions that are difficult to diagnose and treat. Frost hopes that the center’s research will help to identify biomarkers for subtypes of these diseases, which can help determine the best treatment for a given individual. “Ultimately this will benefit our patients,” Frost said. “That’s the key.”