A Clinical Trial Evaluating the Efficacy and Safety of Leflutrozole on Testicular Function

The goal of this clinical trial is to evaluate three doses of the drug leflutrozole on improvement of semen quality in men. It will also study the safety of leflutrozole. The main questions it aims to answer are: * Does leflutrozole improve semen quality? * What medical problems do participants experience when taking leflutrozole? Researchers will compare leflutrozole to a placebo (a look-alike substance that contains no drug). Participants will: * Take leflutrozole or a placebo orally once a week for 16 weeks. * Visit the clinic every 4 weeks for checkups and tests. * Provide semen samples to measure changes in semen quality. * Have their blood tested to measure hormone levels and ensure safety. * Be monitored for any side effects.