This is a 52-week open label single arm study + 24-Month long-term safety extension to investigate the effects of XYOSTED, as testosterone replacement therapy, on adolescent males with either primary or secondary hypogonadism.
The study aims to determine the effectiveness of XYOSTED measured by continuation or induction of puberty in addition to XYOSTED dosage, safety and testosterone levels.
Diagnosed with a deficiency or absence of endogenous testosterone due to primary or secondary hypogonadism of a known etiology. Children with combined hormone deficiencies are permitted to enroll (but the child must already be receiving treatment for concomitant hormonal deficiencies)
Participants receiving prior testosterone treatment must be receiving a stable dose for at least 12 weeks prior to Screening. Treatment naive participants are permitted to enroll.
Have parent(s) or a legal guardian who will voluntarily provide written informed consent for the child to participate in the study
Willing to provide assent for participation in the study
Has abnormal thyroid function tests at Screening. May supplement per usual clinical practice and rescreen up to two times.
Has suspected or known constitutional growth delay in growth and puberty (CDGP)
Has evidence of possible nutritional or gastrointestinal disorder that may impact growth (e.g., abrupt weight loss within the 3 months prior to Screening, unmanaged celiac disease, inflammatory bowel disease)
Has a known allergy or hypersensitivity to XYOSTED, or to any of its ingredients (testosterone enanthate and sesame oil)