Switching from Lynparza to Talzenna and Xtandi safe?

[Har036]

Hello, my husband was on Lynparza for four years. He started on the full dose but over the years the dose was reduced d/t fatigue and decreased blood counts. Last month he discontinued his 100mg twice daily dose when his neutrophil count was too low. We saw his doctor several days ago and although his counts increased were not back to where it would have been safe. His PSA had been undetectable on the lynparza then January psa went up to.104

And last week it was back down to .087.

His physician discussed with us switching to Talzenna and Xtandi but he will continue on a “pause” for another month. He’s due for scans in April. Last scan in October was stable without any new lesions or growth. He’s still getting his Eligard injections. His hematologist wants him to get a bone marrow test to check for other types of blood cancer. This was a very difficult year.

Wondering if the Talzenna and Xtandi would be just as harsh on his blood counts. His hemoglobin is low as well 10.6.

In addition he’s had problems with hypercalcemia for the past year. Zometa infusions caused renal issues so he’s on Xgeva again which is now keeping the calcium under 11.

He also experienced a blood clot in his lung and femur November 2024. Freqent bladder infections as well.

I know I don’t have his history in the proper place, but he was first diagnosed in 2013, Gleason 8.

Treated with SBRT

lupron started 2018

Metastatic- hip and sacrum- radiation

Provenge 2019

Abiraterone and prednisone 2020 stopped working after four months

September 2020 fell fractured hip/hip replacement

Sept 2020 Lynparza started-stopped Jan 2024 restart March 2024 paused again Feb. 2025.

He’s 75 yo.

I’d appreciate feedback.

[j-o-h-n]

Is switching from Lynparza to Talzenna and Xtandi safe?

A I - ChatGPT said:

Switching from Lynparza (Olaparib) to Talzenna (Talazoparib) and Xtandi (Enzalutamide) depends on your specific medical condition, treatment goals, and your doctor's recommendation. These medications are used for different but overlapping indications, primarily in prostate and breast cancer treatment.

Key Considerations:

Medical Supervision: Always consult your oncologist before making any medication changes. They will assess your cancer type, genetic mutations (such as BRCA mutations), disease progression, and response to prior treatments.

Drug Mechanism Differences:

Lynparza & Talzenna: Both are PARP inhibitors, but they have different efficacy and side effect profiles. Switching from one to another may depend on resistance patterns or tolerability.

Xtandi: This is an androgen receptor inhibitor, primarily used in prostate cancer to reduce androgen-driven tumor growth.

Safety & Side Effects:

Talzenna and Lynparza have similar mechanisms but may have different side effects.

Xtandi can cause fatigue, hypertension, and seizures in rare cases.

Combining Talzenna with Xtandi is an approved treatment for metastatic castration-resistant prostate cancer (mCRPC) with BRCA mutations, but safety should be monitored.

Clinical Justification: If you’re switching due to side effects, resistance, or disease progression, your doctor will determine the best approach.

Would be a good idea to update your/his Bio..... All info is voluntary and it will help you/him and helps us too. Regards!!!

Good Luck, Good Health and Good Humor.

j-o-h-n

[Har036 in reply to j-o-h-n]

Thank you!

[j-o-h-n in reply to Har036]

I hope that helped....... and you're welcome...

Good Luck, Good Health and Good Humor.

j-o-h-n

[Har036]

I found some helpful information in your post.

Thanks again.