Another Day Pharma has announced promising Phase II clinical trial results for BZ371A, a novel topical treatment for post-prostatectomy erectile dysfunction (ED). The synthetic peptide, derived from spider venom, demonstrated significant efficacy in improving erectile function in men who underwent radical prostatectomy for prostate cancer.
The Phase II trial involved 74 men aged 40-68 years and evaluated BZ371A's effectiveness both as a monotherapy and in combination with tadalafil, the current standard of care. Success was measured using the International Index of Erectile Function (IIEF) Questionnaire, with improvement defined as an increase of more than 4 points in the erectile function domain.
Superior Efficacy Compared to Standard Treatment
The results revealed that men receiving combination therapy (BZ371A plus tadalafil) were 10 times more likely to respond after 30 days compared to those receiving tadalafil alone, with success rates of 38% versus 4% respectively (p<0.05).
BZ371A monotherapy also outperformed tadalafil alone:
- 15% success rate at 30 days (versus 4% for tadalafil)
- 32% success rate at 60 days (versus 13% for tadalafil)
The topical gel formulation demonstrated excellent tolerability with no serious adverse events reported and no treatment discontinuations due to side effects.
Novel Mechanism of Action
BZ371A represents a significant innovation in ED treatment. The synthetic non-hormonal peptide is derived from the venom of the Phoneutria nigriventer spider, which is known to cause priapism (prolonged erection) in bite victims.
The compound works by stimulating nitric oxide (NO) production, which triggers cyclic guanosine 3',5-monophosphate (cGMP) production. This cascade leads to endothelial muscle relaxation and increased blood flow, resulting in erection. Importantly, BZ371A can induce erections even without sexual stimulation.
This mechanism makes BZ371A particularly valuable for post-prostatectomy patients whose neural pathways have been compromised by surgery. While effective as monotherapy, BZ371A's mechanism complements PDE5 inhibitors like tadalafil, explaining the enhanced efficacy of combination therapy.
Addressing a Significant Unmet Need
"We are delighted that these trial results show that BZ371A is proving to be a well-tolerated, effective option for men undergoing radical prostatectomy, either as monotherapy or concomitantly with tadalafil," said Paulo Lacativa, clinical researcher at Biozeus Biopharmaceuticals in Brazil, which developed the treatment. "The results support the advancement of BZ371A into Phase III trials and reinforce its potential to address other forms of ED."
Carlos Sanchez, Director at Another Day Pharma, added: "BZ371A offers a new way of treating ED that we hope will benefit, in the future, the many men who don't respond to or are unable to take PDE5-inhibitors. We are now seeking strategic partnerships with pharmaceutical companies interested in licensing or co-developing this product."
The need for effective post-prostatectomy ED treatments is substantial. Approximately 60,000-70,000 men in Europe and 161,000 in the US undergo radical prostatectomy annually, with over 90% experiencing ED immediately after surgery. These patients risk irreversible erectile tissue damage without early intervention.
Current treatment approaches, including daily tadalafil for 18-24 months, offer limited benefit, as no existing treatment effectively improves recovery of spontaneous erections. Surgical damage to nerves and blood vessels often leads to long-term loss of erectile function, leaving patients with few effective options to prevent permanent loss of erectile capability.
Market Context and Future Directions
Erectile dysfunction affects between 3-76.5% of men globally, representing up to 87 million men in the US and Europe alone. While PDE5 inhibitors like sildenafil (Viagra) and tadalafil (Cialis) are first-line treatments, approximately 35% of ED sufferers are resistant to these medications, and for 15%, these drugs are contraindicated.
Another Day Pharma, a UK-based company focused on sexual dysfunction therapies, recently partnered with Biozeus Biopharmaceuticals to develop BZ371A. The compound is also currently in Phase II trials for female sexual dysfunction, highlighting its potential broader applications.
Based on these promising results, BZ371A appears poised to advance to Phase III clinical trials, potentially offering a much-needed new option for post-prostatectomy patients and possibly the broader ED market in the future.
