Neoadjuvant Intraprostatic OnabotulinumtoxinA Before Radical Prostatectomy for High-Risk Localized Prostate Cancer

NCT07796490 | Not Yet Recruiting Phase 1 FDA Drug

• 1 other identifier: Pro00046310
• Study Type: interventional
• Target: 30
• Locations: 1 country
• Sites: 1

Brief Summary

This pilot randomized, single-blind, placebo-controlled study evaluates the feasibility, safety, and preliminary biological activity of neoadjuvant intraprostatic onabotulinumtoxinA (BOTOX®) administered before radical prostatectomy in men with high-risk localized prostate cancer. Thirty participants will be randomized 1:1 to receive a single transrectal ultrasound-guided intraprostatic injection of onabotulinumtoxinA (50 units) or placebo 6 to 8 weeks before surgery. Outcomes include feasibility metrics, safety, adverse events, pathological findings at prostatectomy, and postoperative prostate-specific antigen (PSA) levels

Conditions

Prostate Cancer

Outcome Measures

Primary Outcomes (5)

• Participant Accrural

  Number of participants enrolled in the study

  Through study completion, an average of 1 year

• Protocol Adherence

  Proportion of participants who complete study procedures according to protocol requirements.

  Through study completion, an average of 1 year

• Successful Completion of Intraprostatic Injection

  Number of participants who successfully receive the assigned intraprostatic study injection.

  At time of surgery

• Incidence of Adverse Events

  Incidence, severity, seriousness, and relationship of adverse events associated with intraprostatic administration of onabotulinumtoxinA or placebo.

  From study injection through 36 months of follow-up.

• Successful Completion of Planned Radical Prostatectomy

  Proportion of participants who undergo planned radical prostatectomy following study intervention without study-related cancellation or unacceptable delay.

  Within 6 to 8 weeks after intraprostatic injection.

Secondary Outcomes (6)

• Gleason Score at Radical Prostatectomy

  At radical prostatectomy (6 to 8 weeks after study injection).

• Perineural Invasion

  At radical prostatectomy (6 to 8 weeks after study injection).

• Stromogenic Component

  At radical prostatectomy (6 to 8 weeks after study injection).

• Tumor Size

  At radical prostatectomy (6 to 8 weeks after study injection).

• Positive Surgical Margin Status

  At radical prostatectomy (6 to 8 weeks after study injection).

Other Outcomes (1)

• Time to Biochemical Recurrence

  Up to 36 months after radical prostatectomy.

Study Arms (2)

Botox

EXPERIMENTAL

A single transperineal, transrectal ultrasound (TRUS)-guided intraprostatic injection of onabotulinumtoxinA, total dose 50 units, administered 6 to 8 weeks prior to radical prostatectomy.

Drug: OnabotulinumtoxinA (BOTOX®)

Placebo

PLACEBO COMPARATOR

A single transperineal, transrectal ultrasound (TRUS)-guided intraprostatic injection of normal saline placebo administered in an identical volume and injection pattern 6 to 8 weeks prior to radical prostatectomy.

Other: Normal Saline Placebo

Interventions

OnabotulinumtoxinA (BOTOX®) DRUG

A single transperineal, transrectal ultrasound (TRUS)-guided intraprostatic injection of onabotulinumtoxinA, total dose 50 units, administered 6 to 8 weeks prior to radical prostatectomy.

Also known as: Botox

Botox

Normal Saline Placebo OTHER

Participants randomized to the placebo arm will receive a single transperineal, transrectal ultrasound (TRUS)-guided intraprostatic injection of normal saline administered in an identical volume and injection pattern as the active treatment arm, 6 to 8 weeks prior to planned radical prostatectomy.

Placebo

Eligibility Criteria

• Age: 45 Years - 80 Years
• Sex: male
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Male, ≥ 45 years
• Histologically confirmed prostate adenocarcinoma
• Gleason score ≥8 on biopsy
• Candidate for and scheduled to undergo RALP for primary treatment
• ECOG 0-2
• Able to read, speak, and understand English
• Able to provide informed consent

You may not qualify if:

• Prior prostate cancer therapy (radiation, ADT, chemotherapy)
• Metastatic disease
• Known hypersensitivity to botulinum toxin
• Neuromuscular disorders (e.g., myasthenia gravis)
• Active infection, coagulopathy, or contraindication to transperineal injection
• Medications significantly affecting neuromuscular transmission (clinically relevant)
• Any condition compromising safety or protocol compliance

Sponsors & Collaborators

• The Methodist Hospital Research Institute: lead

Study Sites (1)

Houston Methodist

Houston, Texas, 77030, United States

Location

MeSH Terms

Conditions

Prostatic Neoplasms

Interventions

Botulinum Toxins, Type A

Condition Hierarchy (Ancestors)

Genital Neoplasms, Male; Urogenital Neoplasms; Neoplasms by Site; Neoplasms; Genital Diseases, Male; Genital Diseases; Urogenital Diseases; Prostatic Diseases; Male Urogenital Diseases

Intervention Hierarchy (Ancestors)

Botulinum Toxins; Metalloendopeptidases; Endopeptidases; Peptide Hydrolases; Hydrolases; Enzymes; Enzymes and Coenzymes; Metalloproteases; Bacterial Proteins; Proteins; Amino Acids, Peptides, and Proteins; Bacterial Toxins; Toxins, Biological; Biological Factors

Study Officials

• Brian Miles, MD

  Houston Methodist Urology, Houston Methodist Research Institute

  PRINCIPAL INVESTIGATOR

Central Study Contacts

Vivian MacDonnell, MD

CONTACT

7134928703; vmmacdonnell@houstonmethodist.org

Brian Miles, MD

CONTACT

7138170870; bjmiles@houstonmethodist.org

Study Design

• Study Type: interventional
• Phase: phase 1
• Allocation: RANDOMIZED
• Masking: SINGLE
• Who Masked: PARTICIPANT
• Masking Details: Participant will not know if they are receiving Botox or placebo, they will remain blinded.
• Purpose: TREATMENT
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Principal Investigator

Model Details: Participants will be randomized in a 1:1 ratio to receive either a single intraprostatic injection of onabotulinumtoxinA (50 units) or placebo (normal saline) administered 6 to 8 weeks prior to radical prostatectomy. Participants remain in their assigned treatment group throughout the study, and outcomes are compared between parallel treatment arms.

Study Record Dates

• First Submitted: August 20, 2026
• First Posted: September 1, 2026
• Study Start (Estimated): November 1, 2026
• Primary Completion (Estimated): November 1, 2028
• Study Completion (Estimated): November 1, 2029
• Last Updated: September 2, 2026

Record last verified: 2026-08

Locations

US (1)