Umesh Oza, MD: So, we each talked about PSMA-PET [prostate-specific membrane antigen-positron emission tomography]. You and I each know there are 2 radioisotopes certain to totally different brokers, PSMA [and] amino acid, amongst different issues. Can you contact on what 2 totally different radionuclides are available for PSMA-PET, simply typically? Then we are able to discuss slightly bit extra particularly about benefits and downsides.
Jaideep S. Sohi, MD: Absolutely. The first tracer that involves thoughts is gallium-68 PSMA. That’s the one which has been utilized in Australia and Europe for the previous about 7-plus years. Our first FDA-approved tracer within the US was gallium-68 PSMA, which was developed by [University of California San Francisco] and [University of California, Los Angeles] again in December 2020. As the title suggests, it’s a gallium-based imaging agent. The second PSMA agent that’s available is F-18, or fluorine-18 PSMA, which was authorized, I consider, in May 2021. That’s a more recent agent, and now each are in utilization and observe.
Umesh Oza, MD: That’s fascinating as a result of on our facet, the place we’re, in an enormous metropolis, Dallas, we noticed the F-18 agent present up first, after which we noticed the gallium-68. You’re telling me that, in Europe and the remainder of Australia, it’s been round for almost 7 years. It’s fascinating how issues work out about availability in huge cities like this. But I’m hoping we’re seeing extra of a steadiness and that we’re each tracers. We have sufficient information to take a look at what’s finest for our sufferers, what subset of sufferers, what situations, and issues like that. Let’s simply discuss first about how each is made. How are they produced? Is there a distinction between the gallium and the fluorinated PSMA agent?
Jaideep S. Sohi, MD: Yes, and once more, simply to finish the loop from the prior matter, I feel you’ve talked about that you just’ve seen larger utilization, or better utilization, or earlier adoption of F-18 in contrast with gallium. I feel a part of the reason being that the primary tracer, though it was gallium-68 that was authorized within the US, that was, technically available to anyone, however actually in practical phrases, was available to sufferers who may journey to these establishments.
Then, after all, all the pieces was authorized, after which that grew to become available. Maybe that’s the rationale why we had the approval of a tracer, but it surely was not extremely, extensively available. I feel with regard to how they’re produced, the gallium-68 is a generator-produced isotope, and F-18 is produced by cyclotron. Do you need to go into slightly element? How about you? Go into some element about what the distinction between a generator and a cyclotron is.
Umesh Oza, MD: Sure, [with] a cyclotron, you’ve received to have some area. It’s very extremely radioactive, [with a radioactive area of] what was a soccer discipline. But now they’re smaller than that. But they’re very high-radiation areas. They want very huge areas of defending, concrete, and lead, and are very costly. And that’s the place our fluorinated brokers are coming from. For our mainstay F-18 PET-CT, we do it for each different malignancy. A generator is one thing that you’ve got, a guardian, if you’ll. Then it decays to a, we name it a daughter within the nuclear medication world. A generator will make that because it decays, [and] you’ll be able to pull off what you’re making an attempt to supply. In this case, it’s [such a] smaller piece of kit. It does have its personal half-life and decays. But upon getting that generator, you’ll be able to produce that isotope domestically, pretty simply, effectively. And you’ll be able to distribute these mills to smaller areas. You can’t transfer a cyclotron and say, “Hey, I want this cyclotron in my small town right now,” however you’ll be able to transfer mills, or you’ll be able to have a setup the place the mills are nearer to those smaller cities.
Transcript is AI-generated and edited for readability and readability.
