Just started immotherapy trial (neoadjuvent Xaluritamig)

Hello. I haven’t seen any posts in forums about Xaluritamig clinical trial participants so figured I’d share in case there are folks out there who may be considering or who are/were in it to share their experience.

My story: 53yrs. Diagnosed in January after having elevated PSA (~7) found due to suspected Prostatitis. CT clear at the time. PSA went down to ~6, so seemed OK. But a year later, it only went down .2 or so. DRE was suspect, so MRI done. PI-RADS 5. Biopsy was Gleason 9 (4+5 w/ cribriform and PNI). PSMA-PET was somewhat equivocable for rib metasticies, but otherwise prostate contained. Got connected to multidisciplinary prostate cancer team at Fred Hutch in Seattle for a second opinion. They felt that the tiny rib legions were likely from prior injuries and were indifferent about surgery vs. radiation, but all felt a clinical trial would be best due to the high risk of future recurrence (50-80% in 10 years was shared). Two studies were available given my risk profile and both ended in RP. It was a tough decision, but Xaluritamig seemed to have very promising resulting in late stage cancer and using in advance of surgery is similarly promising. The drug is also called Amgen 509 and the study is Amgen NEO. It’s an immunotherapy that targets STEAP-1 cells by training T-Cells to fight it - forgive any layman’s mistakes but details are online.

The study combines Xaluritamig with ADT (Orgovyx), the later of which I’ve been on for a month. Beside poor sleep, zero libido, mild hot flashes (annoying but not sweat drenching), and a bit more easy to tire when exercising, no other ADT symptoms to speak of which is awesome. I realize that those things all sound objectively terrible in almost any other context.

Today was my first infusion of the immunotherapy, which starts with a tiny dose, increasing each week for two more weeks for Cycle 1, then two more treatments in Cycle 2, then RALP about 2 weeks later (ADT stops then). Nice thing about the study is it pays for a post-treatment MRI, so if 3 months of ADT plus the Xal shrinks things a lot, it will help with surgical plans.

3 hours post-infusion I have no side effects from it, but certainly will expect flu-like symptoms at some point, maybe not until next week though. I have a veritable pharmacy of meds to manage potential symptoms. They give steroids (dexamethasone) to calm the immune system and preemptive Tylenol. Then I have drugs for muscle pain, diarrhea, and nausea as needed. Joining a trial has added a ton of visits, tests, and blood draws to what could have been a straightforward treatment plan. My MyChart periodically explodes with test results and appointments check-ins (6 appts today and around 8 or 9 tests). I took two special trips to Seattle to enroll and will take a total of 6 more in-person plus roughly biannual visits for 3 years. Luckily Amgen pays for travel expenses up to a very reasonable amount, and that includes my wife.

So, all in all, it feels really good to finally be in this part of the study and be feeling well enough to write this while waiting for the Day 1 observation period to be over.

Curious if anyone else is in this trial and happy to share more as this progresses if folks are interested.