Method to Predict Success of Sperm Retrieval in Men with Nonobstructive Azoospermia

Background & Unmet Need

• The optimal management of nonobstructive azoospermia (NOA) is testicular sperm extraction (TESE) and intracytoplasmic sperm injection (ICSI)
• However, sperm are absent in the testes of many men with NOA, and preoperative parameters cannot reliably predict the presence of retrievable testicular sperm
• Surgical sperm retrieval fails in ~50% of cases
• Men with unsuccessful sperm retrieval incur risk of morbidity, psychologic stress, and financial expense
• Female partners of men with NOA who fail sperm retrieval may undergo unnecessary ovarian stimulation
• Unmet Need: Non-invasive method to predict patient success of retrieving viable sperm during TESE

Technology Overview

• The Technology: Diagnostic test to predict the success of retrieving sperm from a male with NOA during TESE by measuring expression levels of the heat shock factor Y-linked gene (HSFY) in testicular or semen samples
• The Discovery: Patients with NOA who fail microdissection TESE have low testicular mRNA expression of the AZFb gene HSFY
• PoC Data: In a study of 54 men with NOA who underwent microdissection TESE, HSFY mRNA expression levels predicted successful sperm retrieval with 67% sensitivity and 93% specificity
• Good discrimination between the groups in all histologic variants of NOA (92% sensitivity for Sertoli cell only (SCO) histology, 67% sensitivity for maturation arrest (MA) histology)
• Probabilities of sperm retrieval for HSFY-positive patients was 93%, compared to 31% for HSFY-negative patients

Technology Applications

• Selection of male NOA patients with highest probability of successful sperm retrieval during TESE

Technology Advantages

• Requires only a small sample of testicular tissue
• High specificity and sensitivity in all histologic variants
• qRT-PCR enables rapid, straightforward HSFY mRNA detection