Botulinum may offer option in BPH, but results are equivocal

May 25, 2005

Botulinum toxin A (Botox) injections show potential for providing a quick, easy, and safe treatment option for men with lower urinary tract symptoms related to BPH, but two small studies presented yesterday provided equivocal results regarding the efficacy of this investigational approach. U.S. researchers tested their 10-minute, ultrasound-guided technique in a two-part study. In the first part, 10 patients were injected with botulinum, 100 units, to assess safety, International Prostate Symptom Score, flow rates, and bother scores. In the second part, 30 patients received 200 units of botulinum in a sham-controlled, double-blind study, and sequential MRIs were taken pretreatment and at 1 and 3 months post-treatment to measure prostate volume.

Botulinum toxin A (Botox) injections show potential for providing a quick, easy, and safe treatment option for men with lower urinary tract symptoms related to BPH, but two small studies presented yesterday provided equivocal results regarding the efficacy of this investigational approach.

U.S. researchers tested their 10-minute, ultrasound-guided technique in a two-part study. In the first part, 10 patients were injected with botulinum, 100 units, to assess safety, International Prostate Symptom Score, flow rates, and bother scores. In the second part, 30 patients received 200 units of botulinum in a sham-controlled, double-blind study, and sequential MRIs were taken pretreatment and at 1 and 3 months post-treatment to measure prostate volume.

In the 10-patient group, mean IPSS scores dropped from a mean of 21.2 before treatment to 9.7 at 7 months. In the 30-patient group, little difference was seen in IPPS scores and flow rates between the sham and treatment groups, and MRIs were unable to show any change in prostate size.The procedure was safe, as none of the patients required immediate cateheterization, and one of the 40 men treated has gone into retention. Epididymitis occurred in one patient.

"This is a treatment that is fast, easy, and the patients tolerate it well," said Thayne Larson, MD, of the Institute of Medical Research in Scottsdale, AZ. "A longer study with more patients is important."

Dr. Larson also presented data on behalf of Federico Guercini, MD, of Università di Perugia, Rome, who led a multicenter study of 16 patients with severe BPH. All received intraprostatic injections of botulinum, 300 units. Mean IPSS dropped from 24 at baseline to 9 at 6 months (p=.002), and mean prostate weight dropped from 106 grams to 53 grams.

The authors said, based on their findings, they considered botulinum injections a "mutually exclusive alternative to surgery" in men with severe BPH.