- Clarus Therapeutics, a specialty pharma focused on men's health, has won U.S. approval for a testosterone replacement therapy meant to treat adult males who have certain forms of a condition that impairs testosterone production.
- Approval of Clarus' Jatenzo, an oral softgel formulation of testosterone, was based on results from a late-stage study wherein 87% of hypogonadal men treated with the drug had a daily average testosterone level in the normal range. Adverse events were generally consistent with other testosterone replacement therapies.
- However, the Food and Drug Administration warned that Jatenzo should not be used for aged-related hypogonadism, where benefits have not be proven. Jatenzo will carry a boxed label warning because of the potential for raising blood pressure and boosting risk for heart attack and stroke in older men.
It's not been a speedy route to the market for Jatenzo (testosterone undecanoate).
The drug was in late-stage testing in the U.S. and Germany back in 2012, when it was known as Rextoro. Clarus would submit Rextoro for FDA approval in January 2014. But the agency's Bone, Reproductive and Urologic Drugs Advisory Committee and Drug Safety and Risk Management Advisory Committee voted 18-3 that the benefit/risk profile did not support approval, and 12-8 that there was not enough evidence of efficacy.
By May 2016, Clarus had began another Phase 3 trial, inTUne, comparing the then-renamed Jatenzo against an active comparator, Axiron (topical testosterone). The company submitted Jatenzo for approval in June 2017.
Jatenzo is now OK'd for use in men with hypogonadism due to specific medical conditions, such as genetic disorders like Klinefelter syndrome or tumors that have damaged the pituitary gland.
While cleared for U.S. market, the drug's label carries a boxed warning because of the potential to raise blood pressure. It also cautions against being used for age-related forms of hypogonadism.
"It’s important to emphasize that this drug should not, like other testosterone treatments, be used to treat older men with 'age-related hypogonadism,'" said Hylton Joffe, director of the Division of Bone, Reproductive and Urologic Products in the FDA's Center for Drug Evaluation and Research.
"The benefits of testosterone therapy, including Jatenzo, have not been established for this use, and Jatenzo’s effects on raising blood pressure can increase the risks of heart attack, stroke and cardiovascular death in this population," Joffe added.
Oral administration holds several advantages over other types of testosterone replacement therapy. With gels, for instance, there's a risk the testosterone could transfer to other people. Oral therapy also doesn't have the same irritation that can be associated with transdermal patches, and it can be more convenient than intramuscular injections.