Tuesday, Endo Pharmaceuticals Holdings Inc. (ENDP) released new long-term clinical trial data in men with hypogonadism who were treated for 21 months with testosterone undecanoate injection, a long-acting testosterone replacement therapy in development in the U.S. for treatment of hypogonadism. Endo Pharmaceuticals is engaged in the development of generic prescription drugs used to treat and manage pain.
Hypogonadism, also known as low testosterone, is a common under-recognized and under-treated condition that affects an estimated 13.8 million men in the United States. Only 9% of American men with low testosterone are currently being treated with testosterone replacement therapy. Low testosterone is associated with other serious medical conditions including diabetes, cardiovascular disease and metabolic syndrome.This open-label study enrolled 130 hypogonadal men with serum testosterone levels below 300 ng/dL at study entry. NEBIDO was dosed as an intramuscular injection, 750 mg at baseline, at week four, and then every 10 weeks throughout the remainder of the 21-month study. Approximately 70% of patients completed all NEBIDO injections.
According to the company, results showed that average testosterone levels were maintained within the normal range over the 21-month study, and NEBIDO was generally well tolerated. NEBIDO is currently under review at the U.S. Food and Drug Administration. Safety data showed that NEBIDO was generally well tolerated over the 21-month study, with reported side effects characterized as mild and non-serious.
Earlier report at the final stage data evaluated NEBIDO's effectiveness and safety over the primary six month treatment period among the hypogonadal men, with 94% of patients achieving the average testosterone level within the normal range over the 10 week treatment.
Four days following the first injection the average testosterone level for the patients rose into the normal range at the first sampling point,
Safety data showed that NEBIDO was generally well tolerated over the 21-month study, with reported side effects typically characterized as mild and non-serious. The most common side effects reported were acne, 6,2% and increased prostate specific antigen 5.4 %.
ENDP is currently trading at $18.37, up $0.45 or 2.51%, on a volume of 0.79 million shares on the Nasdaq.
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June 05, 2026 16:18 ET A busy week for economic news flow saw a slew of reports being released that reflected the trends in the U.S. labor market. In Europe, economic growth and inflation data gained attention as the European Central Bank and Bank of England head for policy session later in the month. In Asia, the monetary policy session of the Indian central bank was in focus as the country, a major oil importer, reels under the pressures of a weaker rupee and rising inflation.