Proof-of-concept Study to Evaluate the Safety and Efficacy of Tryptophan in Patients with BPH.

Inclusion criteria

• Written informed consent;
• Male patients with BPH for which tamsulosin is the therapeutic option per SoC;
• Aged ≥50 and less than 75 years old;
• With prostate volume ≥30 cm3 by TRUS;
• Diagnosed with LUTS defined by a stable IPSS total score ≥13 points.

Exclusion criteria

• Patients with post-void bladder residual volume ≥250 ml;
• Patients with intravesical obstruction from any cause other than BPH;
• History of any procedure considered an intervention for BPH;
• Patients with active urinary tract infection;
• History of recurrent urinary tract infections;
• Current prostatitis or diagnosis of chronic prostatitis;
• History of prostate or invasive bladder cancer;
• Use of 5 α-reductase inhibitors within 6 months;
• Phytotherapy within 2 weeks before entry;
• Use of serotonin reuptake inhibitors or monoamine oxidase inhibitors;
• Patients with acute or chronic kidney failure;
• Patients with diagnosed or suspicion of intolerance to lactose;
• Patients submitted to general anesthesia in the past 4 weeks;
• Known intellectual disability that may hampers giving informed consent and would make the patient inappropriate for entry into this study, in the judgment of the investigator.