Safety and Efficacy of Weekly Testosterone Cypionate Auto-Injector in Men With Hypogonadism

Hypogonadism in adult males is characterized by inadequate testosterone production and may be associated with reduced energy, decreased libido, diminished muscle mass and strength, impaired physical function, and other clinical symptoms. Testosterone replacement therapy is commonly used to restore serum testosterone concentrations to the normal physiological range and improve symptoms associated with testosterone deficiency. This Phase 3, multicenter, single-arm, multiple-dose study is designed to evaluate the long-term efficacy, safety, pharmacokinetic profile, and usability of testosterone cypionate administered subcutaneously via a prefilled weekly auto-injector in adult males with hypogonadism. The study seeks to characterize the ability of the investigational product to achieve and maintain serum testosterone concentrations within the target eugonadal range during chronic administration. Participants will initiate treatment with a weekly subcutaneous dose of testosterone cypionate administered using the auto-injector. Dose adjustments may be implemented during the study based on serum testosterone concentrations to optimize therapeutic exposure. Pharmacokinetic assessments will be performed to characterize testosterone exposure following repeated dosing and to evaluate maintenance of testosterone concentrations over time. In addition to evaluating testosterone concentrations, the study will assess the long-term safety and tolerability of weekly subcutaneous testosterone cypionate. Safety evaluations will include monitoring of adverse events, clinical laboratory parameters, vital signs, physical examinations, and other assessments routinely used to evaluate testosterone replacement therapy. The study will also evaluate participant experience with the auto-injector, including ease of use and successful self-administration. Information obtained from this study is intended to support the clinical evaluation of a convenient, once-weekly subcutaneous testosterone replacement option for adult males with hypogonadism. This study includes a treatment period and an extension phase to provide additional long-term safety and efficacy data following repeated administration of testosterone cypionate using the auto-injector device.