2004-04-09 at 10:09:00 am #6914Molecular Imaging: Tomorrow’s Stethoscope
General Electric is betting that molecular imaging is medicine’s next frontier — and a great growth opportunity.Doctors love To scan their patients — whether it’s with X-rays, ultrasound, MRI (magnetic resonance imaging), or CT (computerized tomography). Doctors rely on imaging technologies to pinpoint what’s wrong with patients before they treat or operate. As wonderful as these devices may seem, one day we will look back and think they are as crude as a stethoscope. Or, rather, the way doctors use them today will seem crude.
That’s because, for the most part, these machines are used to look inside our bodies at the anatomical level — at our organs and tissues and bones. But as our understanding of the human genome and its links to disease unfolds, doctors will increasingly use these machines and others to look at what is happening inside our bodies at the molecular level — at our cells and genes and proteins.
Already, there is a machine that does this: the PET (positron-emission tomography) scanner. As Michael Phelps, the inventor of PET, once told me, “The PET scan is a way to measure the molecules of the body. It makes visible to us the living chemistry of our bodies.” The way it does that is by taking a trace amount of radioactive material, inserting it into the body, and seeing what happens to it. Today, PET scans are used mostly with cancer patients to watch how much glucose a given piece of tissue is consuming (cancer cells consume a lot of glucose). But its application to other color=#0000ff diseases is limited only by the harmless radioactive contrast agents designed to monitor a specific biological function or find a specific molecular target within the body.
Indeed, it is these contrast agents that are the key to molecular medicine. Given the right agents, even older color=#0000ff technologies such as MRI () can be used to monitor molecular events. “We need new molecular probes,” Phelps says. As scientists find out how genes give rise to specific diseases and cause a cascade of protein-cell interactions, contrast agents that target those interactions can be developed. Nadeem Ishaque, who heads up the molecular medicine group at GE Research, says, “It is becoming possible to look at fundamental aspects of the cell and tissue that we could not before. We can now design these contrast agents to attach to very specific events.” In that way, they are just like drugs. The difference is that these agents would be seeking biomarkers of a disease — the molecular symptoms — rather than trying to block the disease itself. But these molecular symptoms arise early, and identifying them via molecular imaging holds the promise of personalized medicine.
Molecular imaging also holds the promise of huge profits for whoever can figure it out first. That’s why General Electric ( GE) is in the midst of buying Amersham, a British molecular imaging company, for $9.5 billion. It is the shift from anatomical to molecular imaging that is behind this acquisition. Amersham will be rolled into GE Medical Systems — the market leader in medical imaging machines such as those used for X-ray, ultrasound, MRI, and PET scans — and the whole thing will be renamed GE Healthcare Technologies. The Amersham acquisition is so important to the future of this business that Amersham’s current CEO will become the new boss — a departure from GE’s usual practice of putting its own people in charge of acquisitions. Steve Bolze, the GE executive who will help oversee the integration of Amersham into GE, notes that “GE Medical Systems is not in the contrast agent business today. That is Amersham’s business.”
If more contrast agents were developed that could reliably diagnose more diseases, GE would be able not only to sell more of its medical imaging machines but also to generate recurring revenue from the contrast agents. Those agents are like the profitable ink cartridges sold for computer printers that have to be constantly replenished. “The opportunity we see,” Bolze says, “is [that] as you go from anatomical imaging to molecular imaging, you are going to be changing how clinical medicine is done. It will be more personalized to a specific patient’s genetic profile or how they metabolize a given medicine. Instead of the see-and-treat model, we will move to a new model that is more predictive. That is when you start getting into more targeted diagnostics.” And that is the opportunity that GE is eyeing.
Whether GE will be able to capitalize on that opportunity hinges on as-yet-undiscovered links between genes and diseases, the identification of biomarkers for those diseases, and the development of contrast agents (which require FDA approval) that will let doctors see those biomarkers. So this is a long-term opportunity. Today, molecular imaging represents less than 5 percent of the overall medical imaging industry. I’d say that if it ever reaches 50 percent, we’ll know that personalized medicine has finally arrived.