A Phase 2 Study of Methylene Blue Photodynamic Therapy for Treatment of Breast Abscesses

Summary

The objective of this Phase 2 study is to evaluate the efficacy of methylene blue photodynamic therapy (MB-PDT) performed at the time of percutaneous breast abscess drainage for disinfection of breast abscesses. The study includes two arms: (1) standard of care breast abscess drainage and (2) MB-PDT plus standard of care breast abscess drainage. The primary endpoint is time to resolution of clinical symptoms. Secondary endpoints include imaging evidence of abscess resolution, abscess recurrence, need for repeated intervention, and cure rate across treatment groups. Responses will be compared between the two study arms for the per protocol population to determine the efficacy of MB-PDT relative to standard of care. The investigators hypothesize that the addition of MB-PDT to standard of care will significantly reduce the time to symptom resolution, compared to standard of care alone.

Conditions

• Breast Abscess

Interventions

PROCEDURE

Standard of care breast abscess drainage

All subjects will receive ultrasound-guided percutaneous abscess drainage in a procedure room. The site will be prepared and dressed following standard of care sterile procedure, and a needle/catheter will be advanced under ultrasound guidance into the abscess. The abscess will be drained by syringe aspiration, and the cavity will be flushed with sterile saline. Aspirated abscess fluid will be delivered to the Clinical Microbiology Laboratory for processing, including bacterial identification and antibiotic susceptibility testing.

DRUG

Methylene Blue

Following standard of care breast abscess drainage, for subjects randomized to the photodynamic therapy arm, sterile, clinical-grade methylene blue will be infused into the abscess cavity at a concentration of 100 µg/mL via the same needle/catheter used for drainage. The volume introduced will be matched to the amount of abscess material aspirated during the standard of care drainage. After a 10-minute incubation interval, methylene blue will be aspirated and the cavity flushed with sterile saline to remove methylene blue that has not been taken up by microbes.

DRUG

Lipid Emulsion

For subjects randomized to the photodynamic therapy arm, immediately prior to illumination a lipid emulsion will be administered directly to the abscess through the drainage needle/catheter at a concentration of 0.1%. This lipid emulsion will be either Intralipid or Nutrilipid. The lipid emulsion serves to gently distend the cavity, and through light scattering, homogenize the light dose to the walls of the cavity. The volume administered will be matched to the amount of abscess material aspirated during the standard of care drainage. Following laser illumination, the lipid emulsion will be aspirated and the cavity flushed with sterile saline.

DEVICE

Insertion of optical fiber

For subjects randomized to the photodynamic therapy arm, a sterile, single-use optical fiber will be advanced to the approximate center of the abscess cavity via the same needle/catheter used for abscess drainage under ultrasound guidance. This will be connected to the clinical laser system via SMA connector for delivery of treatment light.

DEVICE

Laser illumination

For subjects randomized to the photodynamic therapy arm, laser illumination for photodynamic therapy will be delivered by a laser system operating at 665 nm (ML7710, Modulight, Tampere, Finland) at a fluence rate of 20 mW/cm\^2. The laser power required to achieve this fluence rate will be calculated based on abscess size. Illumination will be delivered for \~20 minutes, resulting in a total delivered fluence of 25 J/cm\^2.

PROCEDURE

Photodynamic therapy

For subjects randomized to the photodynamic therapy arm, the photodynamic therapy procedure comprises the methylene blue, lipid emulsion, insertion of optical fiber, and laser illumination interventions.

Sponsors & Collaborators

• University of Rochester

  lead OTHER

Study Design

Allocation

RANDOMIZED

Purpose

TREATMENT

Masking

DOUBLE

Model

PARALLEL

Eligibility

Min Age

18 Years

Sex

ALL

Healthy Volunteers

No

Timeline & Regulatory

Start

2026-04-30

Primary Completion

2031-03-31

Completion

2031-03-31

FDA Drug

Yes

Countries

• United States

Study Locations