3rd & 4th pBAT cycle results with daro question

[Ichthus316]

Started 3rd pBAT cycle on 6-4-24 with a PSA of 0.58 measured 1 day earlier, 32 days after last of 6 T injections. Started 4th cycle on 7-26-24 with a PSA of 0.59 measured 2 days earlier, 34 days after last of 9 T injections. Tomorrow I will start my first loT phase with darolutamide (see below question for my fellow BAT-men) with a PSA of 2.25 measured 7 hours after the last of 11 T injections.

6-20-24, end of 3rd hiT cycle (9 injections):

PSA = 2.17 (similar to previous 3 hiT cycles)

T = 1346 (drawn approximately 48 hrs after 8th T injection, delayed to check Tp half-life)

E2 <15 (took a single .0625 dose of letrozole, will eliminate this on the next hiT cycle)

7-24-24, end of 3rd loT cycle, 34 days after last T injection:

PSA = 0.59 (similar to previous cycles)

E2 = 13 (target is 20, so will increase # of days on low dose E2 patch)

8-16-24, end of 4th hiT cycle, drawn 7 hours after 11th T injection:

PSA = 2.25

E2 ultrasensitive pending

I recently obtained a script for daro (Nubeqa) from my MO. I plan to take a half dose (300 mg) twice daily for the 1st 2 weeks of loT and then measure PSA. Regardless of the result, I plan to wait another week or two and re-measure since this is my first cycle using daro. If PSA is not well under 0.5 (target is <0.1) after 4 weeks, I may have to increase the dose on the next cycle, assuming that I’m handling the SE’s okay.

Sound reasonable?

[KocoPr]

That all sounds reasonable. I am thinking of taking half doses of daro on next low T cycle.

I can tell you have done your homework.

Are your complete cycles around a month? Ie 2 weeks T-prop (what doses) and then 2 weeks daro with 6 days clearance? It kinda sounds like you’re adjusting it on the fly according to PSA which is the beauty of propianate and n=1.

I myself am embarking on a 90 day cycle of 60 days on high T and 30 days Orgo and Daro.

Oh are you taking an ADT like Orgovyx?

[Ichthus316 in reply to KocoPr]

Since I’m Gleason 9, I’m motivated to do research once in a while to keep the PCa guessing. I’m trying to improve my protocol with hopes of delaying resistance. That’s what I find attractive about BAT and adaptive therapies.

My Tp dose is 50 mg eod, which results in peak T of around 2500. I began with a 30 day cycle and am gradually working toward a 60 day cycle (30 days hiT, 30 days loT). This time frame is similar to the ExBAT trial. Part of my reasoning stems from reading the following in a reply to one of my posts from a guy with lots of BAT experience: “a 4 week castrate period following a 1 week washout of the T-prop...is how long it takes for the androgen receptors (AR) to up-level in number and activity in preparation for the next high-t BAT cycle."

I also plan to eventually integrate some rBAT cycles, as it is my understanding that the majority of DNA DSB’s occur within the first few days of SPT. I’ve also read something similar about loT: “In a study where daily biopsies of the prostate were done after the start of ADT, maximal apoptosis occurred by day 3 and was virtually absent by day 7.”

I receive an Eligard shot every 12 weeks, so ADT is always in the background. The reason I plan to take a half dose, restrict daro to 2 weeks (with a 1 week washout) and limit it to every 3rd cycle is because a) it’s a new drug for me; b) I don’t want to develop resistance to ARSIs; and c) that’s what RH was doing at last report. I believe (not 100% sure) that he and others in one of the support groups were concerned that ARSIs could eventually become fuel for PCa growth.

[dhccpa in reply to Ichthus316]

How long have you been on BAT since you started?

[Ichthus316 in reply to dhccpa]

I began the first cycle March 2024

[KocoPr]

I read your bio, do you have any mutations germline or somatic?

[Ichthus316 in reply to KocoPr]

It’s my understanding that a well-designed BAT program should work for most guys who don’t have NEPC. Since BAT is my primary therapy, I’m hoping to delay the mutations puzzle a while longer.

[dhccpa in reply to Ichthus316]

Thanks!

[Justfor_]

I would front load the Daro with full dosage during the first week, half that the second and if successful a quarter after that. Total amount taken per cycle the same but more even blood concentration and a more rapid high to low T transition.

[Ichthus316 in reply to Justfor_]

I like the concept of front loading for a more rapid transition from high to loT. But I'm wary of side effects and possible long term negative effects of ARSIs. That's why I had planned to take a half dose for two weeks and then let it clear. If my math is correct, starting with a full dose and halving it for 2 consecutive weeks results in 75% more Daro per cycle than originally planned. That may be where I end up if PSA doesn't drop off the table as I'm hoping.

How about this compromise:

1st 5 days: full dose

2nd 5 days: half dose

3rd 5 days: quarter dose

This results in only 25% more Daro for the first ARSI cycle than originally planned yet preserves the concepts you suggested.

[Justfor_ in reply to Ichthus316]

I was of the impression that you were planning Daro for 4 weeks not two. To this plan I counter-proposed. With only 2 weeks I don't think PSA 0.1 is a feasible option. But you can try and see what will happen. You may be an exceptional responder. So, your 3x5 days plan is worth trying. Best of luck.

[Ichthus316 in reply to Justfor_]

Yes, sorry about that. I should have phrased my proposed plan more clearly. The PSA target of 0.1 is more of an intermediate target, not something I expect to achieve on the first cycle of Daro. If I handle the SEs well, I am prepared, if necessary, to up the dose on future cycles (or extend loT) until I reach the target. But as long as PSA at the end of each loT cycle is trending down, I will be happy to stay the course. Perhaps ambitiously, I will also be searching for the minimum effective dose that drops my PSA until it becomes undetectable.

Thanks for your insightful recommendations, I seem to recall that you have gained much experience by dose adjusting bicalutamide.

[Scout4answers]

Watching your progress on BAT with interest.