Zachary Klaassen: Hi, my name is Zach Klaassen, Urologic Oncologist and I'm joined on UroToday by Dr. Carlos Granados. We are in Cartagena, Colombia for the 2025 SCU annual meeting. Carlos, thank you for joining us.

Carlos Granados: Thank you, Zach. Thank you very much.

Zachary Klaassen: We're going to talk today about the future of PSMA theranostics, and specifically, before we get into
the future, let's talk about the past. We've had VISION in 2021, PSMAfore, 2024. What are your thoughts on those trials. Maybe explain for our listeners what those results were.

Carlos Granados: Sure. The VISION and PSMAfore studies support the use of lutetium PSMA-617, in patients with progressing castration-resistant prostate cancer. In the VISION study, we saw that all patients received treatment with taxanes and with ARPIs, across the board, and in the PSMAfore study, the fundamental difference was that the patients were chemotherapy-naive. In both studies it was very important to show a high expression of PSMA, primarily through PET images using PSMA PET, and be sure that there were no discordant lesions when comparing the PET imaging study with conventional or FDG PET images.

Zachary Klaassen: I think when you look at Colombia, what's the utilization of PSMA, radioligand therapy, currently in your guys' country?

Carlos Granados: Yes, in Colombia we are now seeing ever-increasing access to PET PSMA. Currently there are 32 PET units throughout the country; most of them can perform PET scans with 18F-PSMA-1007, and at some centers - only a few centers, actually - they can perform PET scans with 68Ga-PSMA-11. Some facilities are also able to perform PSMA imaging using SPECT/CT, which, basically, is used for the most part when they have no access to PET images. As for radioligand therapies, here in Colombia we use Lu-PSMA-I&T, because PSMA-617 has not yet been approved by the regulatory authorities. So we continue to use I&T.

In any case, we do have less access to lutetium than to PET imaging. Basically, it is performed only at high-level referral hospitals, and there are only a few of these facilities, basically because of all the regulatory procedures that need to be satisfied. So really the fact that there are only a few facilities, added to the issue of costs, makes this therapy not yet as easily accessible as we would like, but things have been improving in recent years.

Zachary Klaassen: Excellent. I know we've seen mCRPC, two studies there. We now have the lutetium moving up in the disease space, so metastatic hormone-sensitive prostate cancer. What are your thoughts on lutetium moving up to mHSPC?

Carlos Granados: Yes, I think that there is growing evidence for it at different phases in the progression of the disease. For example, there was the LuTectomy study, which showed that lutetium therapy may be safe in a neoadjuvant setting. We need more evidence, but I think it won't take long. Likewise, in cases of hormone-sensitive progression, we also know that it is being tested as part of combination therapies, systemic therapies, or targeted therapies like radiotherapy. So it's just a matter of time until we will surely see radionuclide therapies being used in much earlier-stage scenarios.

Zachary Klaassen: Excellent. I know we've had lutetium, now we have actinium, we have lead coming, we have terbium. What radioligand therapies are you most excited about?

Carlos Granados: We’re all really looking forward to them. As for actinium, we know that its high-energy properties have shown very promising results in terms of tumor control. We know there is some concern about xerostomia as an adverse effect, but in terms of getting the disease under control, it is seen as offering very promising possibilities. The same goes for terbium and lead, which also seem very promising, above all in small-volume micrometastatic disease.

Zachary Klaassen: Awesome. It's been a great conversation. Any take home messages, conclusions for our listeners? Well, in terms of theranostics, I think we're just getting started. There's a long road ahead. We are going to see radionuclide therapies becoming involved at various stages of disease.

Carlos Granados: Certainly we'll be transitioning a bit from fixed dosages to individualized dosages, perhaps guided by dosimetry. We're also redefining how to evaluate therapeutic response. So I think we're going to have a lot of work to do, in lots of aspects that are quite exciting for nuclear physicians, urologists, oncologists and above all, for patients as new treatment strategies. I would like to invite everyone to the Congress of the World Federation of Nuclear Medicine and Biology, which will be held next year here in Colombia. We are going to have some very important segments
on theranostics for prostate cancer. It will be held here in Cartagena, from February 13 to 16, so you are all cordially invited.

Zachary Klaassen: Fantastic. Carlos, thank you very much.

Carlos Granados: Thank you, Zach.