BAT therapy - NIH article

[Magnus1964]

Efficacy and safety of bipolar androgen therapy in castration-resistant prostate cancer following abiraterone or enzalutamide resistance: A systematic review.

You X, Huang S, Wang X, Yi C, Gong N, Yu J, Xu C, Xiang Z. Front Endocrinol (Lausanne). 2023 Apr 11;13:1125838. doi: 10.3389/fendo.2022.1125838. eCollection 2022. PMID: 37113653 Free PMC article.

Bipolar androgen therapy (BAT) is a new endocrinologic treatment for castration-resistant prostate cancer (CRPC) that can restore some patients' sensitivity to drugs such as abiraterone (Abi) and enzalutamide (Enz). ...

[GeorgeGlass]

What’s the takeaway?

[SeosamhM in reply to GeorgeGlass]

The paper is a review of existing data, the authors "systematically analyzed the efficacy and safety of BAT in treating Abi- or Enz-resistant CRPC using a meta-analysis." They concluded that "BAT can trigger the resensitization of patients with CRPC to subsequent endocrine therapy and improve the overall survival of patients and their quality of life. However, biomarkers that can predict the efficacy of BAT still need to be identified."

So...IMO, this paper legitimizes the use of BAT as a legitimately effective PCa treatment tool. But since BAT has been on the periphery of standard-of-care, there are no solid predictors of success. The reintroduction of testosterone is a risky business, indeed. I believe TA addressed this or something similar in a recent post. - Joe

[MateoBeach in reply to SeosamhM]

The biomarker is a favorable response to initial cycles of BAT by monitoring PSA. A drop to near baseline at the end of a 28 day cycle. Not dangerous: you just discontinue if there is a larger rise in PSA at 28 days.Not for those with painful bone mets. Clinical trial not required, just monitoring.

[PhilipSZacarias in reply to MateoBeach]

True MateoBeach, but I believe the response may be better when BRCA and other DNA repair defects are present in the germline and/or via liquid biopsy (correct me if I am wrong) , therefore these may predict initial response. I would still go for just doing it and see what the response is. Cheers, Phil

[tango65]

Thanks.!

[Papillon2]

Thnx Magnus.

[Hidden]

The biomarker is AR amplified or copy gain, approx 30% has that. If you add the PARPi Olaparib approx 50% has a PSA drop of more than 50%, especially the AR-V7 which depends on PARP.

[MateoBeach in reply to Hidden]

You sound like someone I know. Greetings.

[Hidden]

BAT worked to resensitize Enzalutamide AND abiraterone in my husband. After failing Xtandi, Zytiga, Provenge, radiation, etc, through 2020, he had 10 cycles of BAT starting in Jan 2021. When BAT failed, he went back on Xtandi in Oct 2021 until June 2022 (9 months).

When Xtandi failed he resumed BAT in July 2022 for two cycles. Then he tried Zytiga again from Sept 2022 to present. (7 more months. He has also switched steroids from Pred to Dexamethasone during this time.) Since the Zytiga has held his psa relatively low (under 20) and Pluvicto isn’t available yet, he asked if he could do another round of BAT once Zytiga fails and didn’t get a hard No. So…..that may be what he does. He loves the high T injections.

Being willing to experiment has gained him 16 months of additional abi and Enza response and another year+ with his response to BAT.

[CAMPSOUPS in reply to Hidden]

Did he have any bone met pain just prior to starting bat?

[Hidden in reply to CAMPSOUPS]

Nothing that required opiates to relieve. I think that was the definition used in trials for "pain". He does take a fair amount of otc pain pills, especially before and after activity.

[CAMPSOUPS in reply to Hidden]

Thanks so much for responding. Yep I heard that was a criteria in the trial(s) but wondered maybe he had some pain and that maybe there is some leeway. I also heard the pain can get worse with BAT but again maybe tolerable depending on extent of bone met pain until benefits of BAT come into play.

[GSDF]

Thanks for this Mag 👍