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Benjamin P. Saylor is associate editor of Urology Times, an Advanstar Communications publication.

This clearance adds onto a previous indication for the BioTraceIO platform in liver tumor ablation.

FDA grants clearance to BioTraceIO360 for kidney ablation

The approval is supported by data from the phase 3 MK-3475A-D77 trial. 

FDA approves pembrolizumab for subcutaneous injection for solid tumors

The Altaviva device is a minimally invasive implantable tibial neuromodulation therapy for patients with urge urinary incontinence. 

FDA approves Altaviva device for urge urinary incontinence

Among the topics covered are BCG dosing and maintenance regimens.

First Assist: The Historical Context of NMIBC, with Kamal Pohar, MD

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Treatments provide a targeted therapeutic strategy for metastatic
castration-resistant prostate cancer. 

PARP inhibitors: Treating mCRPC from a genetic basis 

The FDA has accepted a new drug application (NDA) for zoliflodacin, an investigational first-in-class, single-dose, spiropyrimidinetrione oral antibiotic for the treatment of adult and pediatric patients 12 years and older with uncomplicated gonorrhea, Innoviva Specialty Therapeutics announced in a news release.

The Prescription Drug User Fee Act (PDUFA) target action date for the application is December 15, 2025.

Zoliflodacin is an oral antibiotic that inhibits type II topoisomerase, a bacterial enzyme that plays a key role in bacterial function and reproduction. According to the company, “If approved, zoliflodacin would be the first new antibiotic for treating gonorrhea in decades.”

The FDA has also granted a Qualified Infectious Disease Product designation to zoliflodacin, which enables the agent to benefit from priority review and market exclusivity.

“Today’s acceptance of the zoliflodacin NDA marks significant progress toward delivering health care providers with a potential new oral treatment option for uncomplicated gonorrhea, including infections caused by drug-resistant strains,” said David Altarac, MD, Chief Medical Officer of Innoviva Specialty Therapeutics, in the news release.

 “We look forward to working closely with the FDA during its review and, if approved, we are committed to expediting the availability of zoliflodacin to patients in the U.S.”

The NDA for zoliflodacin is supported by data from several clinical trials conducted through a collaboration with the Global Antibiotic Research & Development Partnership (GARDP). This portfolio of studies includes a pivotal phase 3 trial (NCT03959527) that evaluated zoliflodacin vs a standard of care (SOC) regimen (500 mg ceftriaxone intramuscular plus 1g oral azithromycin) in patients with uncomplicated gonorrhea.

Overall, the trial met its primary end point by demonstrating that zoliflodacin was non-inferior to the SOC regimen regarding microbiological response at the urogenital site at the test of cure visit (6 +/- 2 days following treatment). Specifically, the microbiological cure rate was 90.9% in the zoliflodacin arm vs 96.2% in the ceftriaxone/azithromycin arm, representing a difference of 5.3% (95% CI, 1.4% to 8.7%) across patients in the micro-intent-to-treat (ITT) population.

The 2 cohorts also demonstrated comparable results on the trial’s secondary end point of microbiological response at extragenital (rectal or pharyngeal) sites. Specifically, at pharyngeal sites, the cure rate was 79.2% in the zoliflodacin arm vs 78.6% in the ceftriaxone/azithromycin arm (difference, -0.67%; 95% CI, -20.8 to 16.3). At rectal sites, the cure rate was 87.3% and 88.6%, respectively (difference, 1.23%; 95% CI, -14.4 to 12.6).

Zoliflodacin was generally well-tolerated in the trial. Treatment-emergent adverse events (TEAEs) occurred in 46.2% of patients in the zoliflodacin arm vs 46.4% of patients in the ceftriaxone/azithromycin arm. The most common TEAEs in the zoliflodacin arm included headache (9.9%), neutropenia (6.8%), and leukopenia (3.9%).

There were no deaths or serious adverse events reported in either arm.

In total, the phase 3 trial included 930 patients with uncomplicated gonorrhea, including patients living with HIV. The study enrolled participants across 16 clinical trial sites in the US, Belgium, the Netherlands, South Africa, and Thailand.

According to Innoviva, the phase 3 study was “the largest clinical trial ever conducted for a new treatment against gonorrhea infection.”

Those enrolled in the study were randomly assigned 2:1 to receive 3 g single-dose, oral zoliflodacin (n = 621) or to 500 mg ceftriaxone intramuscular plus 1g oral azithromycin (n = 309). The primary end point was microbiological cure by culture at urogenital sites in the micro-ITT populations, with a non-inferiority margin of 12%. The trial’s secondary end point was microbiological cure at extragenital sites.

“This important milestone demonstrates the crucial role that public-private partnerships can play in tackling the escalating global antimicrobial resistance crisis,” said Manica Balasegaram, Executive Director of GARDP, in the news release.

 “If zoliflodacin is approved, this collaboration paves the way for millions of people across the world to get access to a potentially powerful new drug to treat multidrug-resistant gonorrhea.”

1. Innoviva Specialty Therapeutics receives FDA New Drug Application acceptance for zoliflodacin, a first-in-class oral antibiotic for uncomplicated gonorrhea in adults. News release. Innoviva Specialty Therapeutics. Published online and accessed June 10, 2025. https://innovivaspecialtytherapeutics.com/innoviva-specialty-therapeutics-receives-fda-new-drug-application-acceptance-for-zoliflodacin-a-first-in-class-oral-antibiotic-for-uncomplicated-gonorrhea-in-adults/

2. FDA Grants Priority Review for Zoliflodacin New Drug Application for the Treatment of Uncomplicated Gonorrhea and Assigns Target PDUFA Date of December 15, 2025. News release. Innovia Specialty Therapeutics, Inc. Published online and accessed June 12, 2025. https://www.businesswire.com/news/home/20250612432209/en/FDA-Grants-Priority-Review-for-Zoliflodacin-New-Drug-Application-for-the-Treatment-of-Uncomplicated-Gonorrhea-and-Assigns-Target-PDUFA-Date-of-December-15-2025 

3. Luckey A, Broadhurst H, Daram P, et al. Oral zoliflodacin is non-inferior to a combination of ceftriaxone and azithromycin for treatment of uncomplicated urogenital gonorrhoea: results of a large global Phase 3 randomised controlled trial. Presented at: European Society of Clinical Microbiology and Infectious Disease Global Congress. April 27-30, 2024. Barcelona, Spain. https://gardp.org/wp-content/uploads/2024/04/Zoli001-Topline-ECCMID2024_final_V1.0_23Apr2024_.pdf

The FDA has accepted the NDA for zoliflodacin, a novel oral antibiotic for treating uncomplicated gonorrhea in patients aged 12 and older. Zoliflodacin, which inhibits type II topoisomerase, has been granted a Qualified Infectious Disease Product designation, allowing for priority review. Clinical trials, including a pivotal phase 3 study, demonstrated that zoliflodacin is non-inferior to the standard regimen of ceftriaxone and azithromycin. The trials showed comparable microbiological cure rates at urogenital and extragenital sites, with zoliflodacin being generally well-tolerated and no serious adverse events reported.

The NDA is supported by a pivotal phase 3 trial of zoliflodacin vs ceftriaxone plus azithromycin in patients with uncomplicated gonorrhea. 

News

FDA accepts new drug application for zoliflodacin for uncomplicated gonorrhea

Dr. De La Cerda provides an overview of a patient case involving a 68 year-old male presenting with severe back pain, with an analysis of the clinical presentation, workup, and medical history.

Bone Predominant mCRPC Patient Case

Video content above is prompted by the following:

What are your initial impressions of the case?

Video Series

The FDA has accepted a Biologics License Application (BLA) seeking approval of nivolumab (Opdivo) co-formulated with Halozyme’s proprietary recombinant human hyaluronidase (rHuPH20), or subcutaneous nivolumab, for the treatment of patients with all previously approved solid tumor indications for nivolumab as a monotherapy, monotherapy maintenance following completion of combination therapy with nivolumab plus ipilimumab (Yervoy), or in combination with chemotherapy or cabozantinib (Cabometyx).

Nivolumab is currently approved under several indications, including in combination with ipilimumab for the first-line treatment of patients with intermediate- or poor-risk advanced renal cell carcinoma (RCC), in combination with cabozantinib for the first-line treatment of patients with advanced RCC, for the treatment of patients with advanced RCC who have received prior anti-angiogenic therapy, and in combination with cisplatin and gemcitabine for the first-line treatment of patients with unresectable or metastatic urothelial carcinoma.

The FDA is set to have a decision regarding the subcutaneous nivolumab formulation on or by December 29, 2024.

 According to a news release from Bristol Myers Squibb,

 approval of the formulation would make it the first and only subcutaneously administered PD-1 inhibitor.

“We believe subcutaneous nivolumab has the potential to make a significant difference in the lives of patients, which is reinforced by the FDA’s acceptance of our application,” said Gina Fusaro, PhD, vice president, global program lead, Bristol Myers Squibb, in the news release.

 “Opdivo is a foundational PD-1 inhibitor approved for many different types of cancer, and our continued investment in research that puts patients first remains a priority. If approved by the FDA, the subcutaneous administration of nivolumab would provide patients and their physicians with a new option that delivers the same well-known benefits as IV Opdivo but with the improved convenience of an injection administered in 3 to 5 minutes rather than a 30-to-60-minute infusion.”

The BLA submission is supported by findings from the phase 3 CheckMate-67T trial (NCT04810078), in which subcutaneous nivolumab met the study’s co-primary end points by demonstrating noninferiority to intravenous (IV) nivolumab regarding time average nivolumab serum concentration over 28 days (C

; geometric mean ratio [GMR}, 2.098; 90% CI, 2.001-2.200) and minimum serum concentration at a steady state (C

Data from the study, which were presented at the 2024 American Society of Clinical Oncology Genitourinary Cancers Symposium in San Francisco, California,

 also showed that subcutaneous nivolumab demonstrated noninferiority to IV nivolumab in the key powered secondary end point of objective response rate (ORR). Specifically, the subcutaneous arm demonstrated an ORR of 24.2% (95% CI, 19.0-30.0) per blinded independent central review (BICR), compared with 18.2% (95% CI, 13.6-23.6) in the IV arm.

The safety profile for subcutaneous nivolumab was consistent with that of the IV formulation. Among patients who received the subcutaneous formulation, 8.1% experienced injection-site reactions, with all being low-grade and transient. Deaths due to study drug toxicity occurred in 3 patients in the subcutaneous arm and 1 patient in the IV arm. Most deaths that occurred during the study were due to disease progression.

In total, the phase 3, open-label CheckMate-67T trial enrolled 495 patients with advanced or metastatic ccRCC who had received prior systemic therapy. Patients were randomly assigned 1:1 to receive 1200 mg subcutaneous nivolumab plus rHuPH20 every 4 weeks (n = 248) or to 3 mg/kg IV nivolumab every 2 weeks (n = 247) for up to 2 years of treatment or until disease progression, unacceptable toxicity, withdrawal, or death.

The co-primary pharmacokinetic end points for noninferiority testing were C

 of subcutaneous nivolumab vs IV nivolumab. The key secondary end point was ORR per BICR.

Final completion of the CheckMate-67T study is expected in January 2026.

1. U.S. Food and Drug Administration accepts Bristol Myers Squibb’s application for subcutaneous nivolumab (nivolumab and hyaluronidase). News release. Bristol Myers Squibb. May 6, 2024. Accessed May 7, 2024. https://news.bms.com/news/corporate-financial/2024/U.S.-Food-and-Drug-Administration-Accepts-Bristol-Myers-Squibbs-Application-for-Subcutaneous-Nivolumab-nivolumab-and-hyaluronidase/default.aspx

2. Bristol Myers Squibb announces updated action date by the U.S. Food and Drug Administration for subcutaneous nivolumab (nivolumab and hyaluronidase). News release. Published online and accessed May 21, 2024. https://investors.bms.com/iframes/press-releases/press-release-details/2024/Bristol-Myers-Squibb-Announces-Updated-Action-Date-by-the-U.S.-Food-and-Drug-Administration-for-Subcutaneous-Nivolumab-nivolumab-and-hyaluronidase/default.aspx

3. George S, Bourlon TB, Chacon MR, et al. Subcutaneous nivolumab (NIVO SC) vs intravenous nivolumab (NIVO IV) in patients with previously treated advanced or metastatic clear cell renal cell carcinoma (ccRCC): Pharmacokinetics (PK), efficacy, and safety results from CheckMate 67T. 

4. A study of subcutaneous nivolumab versus intravenous nivolumab in participants with previously treated clear cell renal cell carcinoma that is advanced or has spread (CheckMate-67T). ClinicalTrials.gov. Last updated March 1, 2024. Accessed May 7, 2024. https://clinicaltrials.gov/study/NCT04810078

The FDA is set to have a decision regarding the subcutaneous nivolumab formulation on or by December 29, 2024. 

FDA accepts BLA for subcutaneous nivolumab in solid tumors

Holmium laser enucleation of the prostate using MOSES technology (M-HoLEP) and thulium fiber laser enucleation of the prostate (ThuFLEP) were both safe and effective and led to comparable functional outcomes in patients with benign prostatic hyperplasia (BPH), according to data from a randomized controlled trial (RCT) published in 

However, the study also showed that the M-HoLEP procedure was superior in terms of enucleation time and efficiency, catheterization time, and hospital stay.

In total, the open-label trial included 104 patients who were randomly assigned 1:1 to receive M-HoLEP (n = 52) or ThuFLEP (n = 52). Patients included in the study had been referred to urology for refractory lower urinary tract symptoms or urinary retention secondary to BPH and had failed prior medical treatment.

 Baseline characteristics were similar between both arms. The median prostate volume was 110 mL in the M-HoLEP arm and 103 mL in the ThuFLEP arm.

The primary end point for the study was the length of stay in the hospital. Secondary outcome measures included safety via intraoperative complications, bleeding incidence, operative time, and time to catheter removal. The investigators also assessed postoperative functional outcomes.

Overall, M-HoLEP demonstrated a shorter median enucleation time and significantly higher enucleation efficiency vs ThuFLEP. Specifically, the median enucleation time was 50 minutes with the M-HoLEP procedure vs 57.5 minutes with the ThuFLEP procedure (

 < .001). Further, the enucleation efficiency was 1.97 g/min with M-HoLEP compared with 1.49 g/min with ThuFLEP (

The average hospital stay was also significantly longer for patients who underwent ThuFLEP. Specifically, the mean hospital stay was 6.3 hours in the M-HoLEP arm vs 11.9 hours in the ThuFLEP arm (

The authors also reported, “Our study identified differences across all investigated hemostasis parameters. While hemostasis time did not differ significantly, immediate postoperative outcomes, including hemoglobin drop, CBI time, postoperative hematuria duration, and hematuria scale in both the operating and recovery rooms, significantly favored M-HoLEP in our hands.”

In total, 7.7% of patients in the M-HoLEP cohort vs 30.8% of patients in the ThuFLEP cohort were admitted with immediate postoperative hematuria (

However, postoperative functional outcomes were similar between both arms through 12 months.

The average prostate size was comparable between both cohorts (

 = .3) at 6 months following the procedure, with no significant differences noted in the percentage of prostate-specific antigen reduction (

 = .51) between the 2 arms. Both groups also showed no significant difference in sexual outcomes at 12 months (

One patient in each cohort (1.9%) experienced stress urinary incontinence (SUI; 

 = 1) at 3 months following the procedure. However, no patients reported persistent SUI at the final follow-up visit.

Overall, grade 1 complications were observed in 19.2% of patients in the M-HoLEP arm and 42.3% of patients in the ThuFLEP arm. Further, 6.2% of patients in the M-HoLEP arm and 19.4% of patients in the ThuFLEP arm failed same-day trial of void (TOV) following the procedure (

 = .06), but all patients passed their TOV within 1 week.

No grade 4 of 5 complications were reported in either arm.

Based on these data, the authors concluded, “M-HoLEP and ThuFLEP are safe and effective BPH treatments with comparable functional outcomes. However, ThuFLEP demonstrated lower ambulatory success. Laser choice should depend on the urologist’s preference and expertise, prioritizing patient safety. Larger RCTs are needed to determine whether one technique offers significant clinical advantages.”

1. Elmansy H, Alhelal S, Blahitko O, et al. Thulium fiber laser versus holmium MOSESTM laser enucleation of the prostate for the treatment of benign prostatic hyperplasia: a randomized prospective clinical study. 

2. Thulium Fiber Laser (TFL) vs Holmium MOSES for treatment of benign prostatic hyperplasia (BPH). ClinicalTrials.gov. Last updated August 16, 2024. Accessed July 28, 2025. https://clinicaltrials.gov/study/NCT05240001

A randomized controlled trial compared holmium laser enucleation of the prostate using MOSES technology (M-HoLEP) and thulium fiber laser enucleation of the prostate (ThuFLEP) for treating benign prostatic hyperplasia (BPH). Both procedures were safe and effective, yielding similar functional outcomes. However, M-HoLEP demonstrated superior enucleation time, efficiency, and shorter hospital stays. Postoperative functional outcomes were comparable, but M-HoLEP had fewer complications and better immediate postoperative hemostasis. The study suggests that laser choice should be based on urologist preference and expertise, with larger trials needed for further evaluation.

However, M-HoLEP was superior in terms of enucleation time and efficiency, catheterization time, and hospital stay.

ThuFLEP and M-HoLEP achieve comparable functional outcomes in BPH

 shed light on factors associated with recurrence following high-intensity focused ultrasound (HIFU) for prostate cancer.

 These data point to the importance of careful patient selection for HIFU, as the therapy was shown to be an effective and tolerable treatment option for patients with intermediate-risk localized prostate cancer.

"Focal therapies such as HIFU are an exciting and rapidly evolving option for localized prostate cancer, offering meaningful cancer control while preserving urinary and sexual function," said lead author Kevin Shee, MD PhD, a PGY6 resident at the University of California, San Francisco (UCSF), in correspondence with 

However, our findings highlight that HIFU is not a one-size-fits-all solution—its success depends on careful patient selection based on PSA, Gleason grade, and genomic risk. Tailoring treatment to the right patient is essential to achieving optimal outcomes."

For the study, the investigators conducted a retrospective review of 135 men who underwent a HIFU procedure at UCSF between 2021 to 2023. All patients had a 1-year post-HIFU MRI-fusion biopsy. The median age of patients at diagnosis was 66 years (IQR, 59 to 71).

According to biopsy data collected at a median of 12 months of follow-up, 54% of patients experience a recurrence of grade group 2 or higher disease, and 41% of patients had an in-field recurrence.

Multivariable logistic regression showed that overall recurrence was associated with GG3 or higher disease (HR, 2.62; 95% CI, 1.03 to 6.67) and a prostate-specific antigen (PSA) level of greater than 10 vs less than 6 ng/mL (HR, 5.64; 95% CI, 1.82 to 17.48). Further, in-field recurrence was associated with GG3 or higher disease (HR, 3.11; 95% CI, 1.30 to 7.47) and a high vs low/intermediate genomic risk score (HR, 2.87; 95% CI, 1.18 to 6.99).

The authors also added, “Notably, we found no significant differences in biopsy outcomes between cases treated early at our institution and later, showing no identifiable learning curve with the FocalOne device.”

Data also showed no association between the location of treatment and disease recurrence, in line with prior literature.

In total, 4 patients (3%) in the study underwent a repeat HIFU procedure. At 1 year, the rate of treatment failure, defined as progression to salvage-whole gland therapy or the development of metastasis, was 4%. The overall treatment failure rate was 16%, and the median time to treatment failure was 16 months (IQR, 13 to 18).

The investigators also compared SHIM and International Prostate Symptom Scores (IPSS) before and at 1 year following HIFU. Notably, they found no significant difference between pre- and post-HIFU SHIM scores or IPSSs. Specifically, the median SHIM score was 16 (IQR, 3 to 24) before HIFU and 13 (IQR, 3 to 21) following the procedure. The median IPSS was 6 (IQR, 3 to 12) before HIFU and 6 (IQR, 4 to 10) following the procedure.

There were also no reported instances of Clavien-Dindo greater than 2 complications or the development of rectal fistulae or urinary strictures following HIFU during the study duration.

According to the authors, these findings support the viability of HIFU in patients with intermediate risk localized prostate cancer. Significantly, they found no impact on urinary or sexual function at 1 year following treatment, which is a key advantage of focal therapy over whole-gland therapy, they explained.

However, the authors caution that a key limitation of the study is generalizability, as the data were collected from a single institution in a homogenous cohort.

They write, “Longer follow-up is needed to determine its impact on local progression and metastasis, highlighting the importance of patient selection, especially in those with a high genomic risk, high PSA, or GG3+ disease.”

1. Shee K, Pace WA, Liu AW, et al. Determining optimal patient selection for high-intensity focused ultrasound for prostate cancer. 

. 2025 Aug 2:S2405-4569(25)00174-9. doi:10.1016/j.euf.2025.06.007

High-intensity focused ultrasound (HIFU) is an effective treatment for intermediate-risk localized prostate cancer, but careful patient selection is crucial due to recurrence risks. A study of 135 men at UCSF showed a 54% recurrence rate of grade group 2 or higher disease. Recurrence was linked to higher-grade disease and elevated PSA levels. No significant differences in urinary or sexual function were observed post-treatment. The study highlights the importance of patient selection, especially for those with high genomic risk, high PSA, or GG3+ disease, and calls for longer follow-up.

HIFU was shown to be an effective and tolerable treatment option for patients with intermediate-risk localized prostate cancer. 

Study offers insights into optimal patient selection for HIFU in prostate cancer

A lower dose of abiraterone acetate (AA; Zytiga; 500 mg) demonstrated promise in delivering optimal anti-tumor efficacy and a favorable safety profile compared with the standard 1000-mg dose in the treatment of patients with prostate cancer, according to data from a phase 1 study published in 

“Our findings open the door to more cost-effective and safer treatment for prostate cancer patients, with minimal compromise on efficacy,” said Eric Chan, PhD, and Edmund Chiong, MBBS, PhD, FRCSEd, FRCSI, FAMS (Urology), in a news release on the study results.

These data build off prior working from a global phase 2 trial showing that a 250 mg dose of AA taken with a low-fat meal achieved comparable prostate-specific antigen (PSA) metrics compared with the standard AA dose in a fasting state among patients with castration-resistant prostate cancer (CRPC). However, the authors noted that ensuring patient compliance with a low-fat diet may pose challenges, and thus further determined that a 500-mg dose of AA in a fasted state demonstrated comparable pharmacokinetic (PK) data to the 250-mg dose with a low-fat meal.

The authors added, “Furthermore, our modeling studies revealed that 500-mg AA is promising in achieving optimal antitumor efficacy and diminishing mineralocorticoid-related adverse outcomes simultaneously. In addition, patients will pay less with a half-reduced dose. Currently, data on the administration of 500-mg AA in prostate cancer patients remains insufficient.”

To that end, the investigators conducted a proof-of-concept phase 1 study assessing the efficacy and safety of a 500 mg once-daily AA dose in 2 patients with metastatic CRPC (mCRPC) and 7 patients with metastatic hormone-sensitive prostate cancer (mHSPC). The median age of patients was 72 years (range, 65 to 90).

Patients in the study received 500 mg of AA once daily for 12 weeks plus oral prednisolone 5 mg twice daily for mCRPC and 5 mg once daily for mHSPC. The authors added, “After this period, patients were reverted to the standard 1000 mg dose due to ethical considerations and were followed up with routine clinical visits.”

Overall, data showed that all 9 patients achieved a decline in PSA level by week 12. Further, 78% of patients (7 of 9) achieved a PSA decline of at least 50% at any visit. Six patients with mHSPC achieved a PSA decline of at least 50% by week 4, which further decreased to at least 80% at week 12.

The authors also reported, “24-h PK profiles revealed that the systemic exposure of 500-mg AA was comparable with previous results from mCRPC patients under the same dose and was approximately half of that previously observed or simulated with a 1000 mg dose of AA.”

Low dose AA also showed substantial suppression of testosterone, androstenedione, DHEA-S and cortisol, which “support[s] the pharmacological response of 500-mg AA,” according to the authors.

Further, treatment with the lower-dose regimen maintained CYP17A1 enzyme occupancy at over 80% despite the 50% reduction in systemic exposure to AA.

The lower dose of AA was also shown to be safe and well-tolerated. In total, 6 of 9 patients experienced an adverse event (AEs) of any cause during the 12-week treatment period. The most common AE was hypokalemia. Other AEs included dry throat, weight gain, puffiness of face, and hot flushes. Notably, other reported AEs were not observed in the current study.

Based on these findings, the authors concluded, “Our proof-of-concept phase I study and PBPK/PD modeling results underscored the pharmacological response of the low-dose regimen, and were consistent with our hypothesis that a lower dose of AA is promising for achieving optimal antitumor efficacy, reducing adverse outcomes, and alleviating financial burdens simultaneously. A long-term, large-scale, controlled clinical trial is essential to further evaluate and confirm the clinical efficacy of low-dose AA therapy.”

1. Chiong E, Wang Z, Cheong EJY, et al. Evaluation of exposure-response-safety relationship of model-informed low-dose 500 mg abiraterone acetate in prostate cancer patients. 

2. Lower dose of abiraterone acetate as effective for prostate cancer treatment. News release. National University of Singapore. July 23, 2025. Accessed July 29, 2025. https://www.eurekalert.org/news-releases/1092211

A phase 1 study demonstrated that a 500 mg dose of abiraterone acetate (AA) is as effective as the standard 1000 mg dose in treating prostate cancer, with a favorable safety profile. The study involved patients with metastatic castration-resistant and hormone-sensitive prostate cancer, showing significant PSA declines and comparable pharmacokinetic profiles. The lower dose also maintained CYP17A1 enzyme occupancy and suppressed key hormones effectively. Despite some adverse events, the lower dose was well-tolerated. Further large-scale trials are needed to confirm these findings and assess long-term efficacy.

The 500 mg regimen of abiraterone acetate demonstrated comparable anti-tumor activity and a favorable safety profile compared with the standard 1000 mg dose. 

Thomas E. Hutson, PharmD, DO

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