BioProtect Balloon Spacer shows sustained quality-of-life benefits in long-term study

Use of the BioProtect Balloon Spacer during prostate cancer radiation therapy led sustained preservation of bowel, urinary, and sexual quality of life through 4 years of follow-up, according to updated data from a pivotal, randomized trial of the spacer.¹

Notably, the study also showed a statistically significant improvement in patient-reported sexual function among those who received the rectal spacer, making it the first of its kind to do so, according to BioProtect.

"These long-term results reinforce what we have seen clinically, that rectal spacing can have a meaningful and lasting effect on patients' day-to-day lives following radiation," said principal investigator Daniel Yeong-Jin Song, MD, professor of radiation oncology at Johns Hopkins University in Baltimore, Maryland, in the news release.¹

These findings add on to previously reported safety and efficacy data from the trial, published in the International Journal of Radiation Oncology, Biology, Physics² as well as quality-of-life data presented at the American Society for Radiation Oncology (ASTRO) 67th Annual Meeting in San Francisco, California.³ In total, the study included 164 patients with T1 to T3 prostate cancer. Participants were randomly assigned 2:1 to receive the BioProtect Balloon Spacer or to the control arm.

Previously reported data showed that the trial met its primary end point, with 97.9% of patients who received the balloon achieving a rectal V70 reduction greater than 25% (P < .001).²

The primary safety end point was also met, with fewer grade 1 or greater adverse events (AEs) reported among patients in the treatment arm. Specifically, 18% of patients who received the balloon vs 23% of patients in the control arm reported an AE (P < .001 for noninferiority). Further, 4.3% of patients in the treatment arm vs 6.5% of patients in the control arm reported a grade 2 or higher AE (P = .527).

Quality-of-life data from the trial were recently presented at ASTRO 2025.³ Data showed that at a median follow-up of 32.8 months, patients in the balloon arm experienced a lower incidence both grade 1 or higher (14.2% vs 29.5%; P < .01) and grade 2 or higher (6.9% vs 15.8%; P = .03) rectal toxicity. Patients in the treatment arm also demonstrated lower rates of grade 1 or higher (20.2% vs 42.4%; P < .01) and grade 2 or higher (10.6% vs 22.3%; P = .03) urinary toxicity. According to the authors, “Sexual toxicity trended lower but was not significant (grade ≥1, 12.9% vs 19.9%; P = .28; grade ≥2, 10.3% vs 14.7%; P = .49).”

The recently reported data, which assessed patient-reported outcomes through 48 months of follow-up, confirm the sustained preservation of quality-of-life.

"What stands out in this follow-up is the consistency of the quality-of-life results,” said co-investigator Shawn H. Zimberg, MD, National Director of Radiation Oncology Services at Solaris Health, in the news release.¹ “Seeing these benefits persist for 4 years speaks to the durability of protection that the BioProtect Balloon Spacer provides in real-world treatment settings."

REFERENCES

1. Long-Term Study Reports Sustained Quality of Life Benefits with the BioProtect Balloon Spacer in Prostate Cancer Radiation Therapy. News release. BioProtect. November 7, 2025. Accessed November 11, 2025. https://www.prnewswire.com/news-releases/long-term-study-reports-sustained-quality-of-life-benefits-with-the-bioprotect-balloon-spacer-in-prostate-cancer-radiation-therapy-302607671.html

2. Song D, Dabkowski M, Shpunt I, et al. Long-Term Toxicity and Patient-Reported Quality of Life after Prostate IMRT with or without Biodegradable Balloon Rectal Spacer: Analysis of a Pivotal Randomized Trial. Presented at: American Society for Radiation Oncology 67th Annual Meeting. September 27-October 1, 2025. San Francisco, CA. https://doi.org/10.1016/j.ijrobp.2025.06.1105

3. Song D, Dabkowski M, Costa P, et al. Prospective, Randomized Controlled Pivotal Trial of Biodegradable Balloon Rectal Spacer for Prostate Radiation Therapy. Int J Radiat Oncol Biol Phys. 2024;120(5):1410-1420. doi:10.1016/j.ijrobp.2024.07.2145