Clarus Therapeutics, a Northbrook, Ill.-based privately held biopharmaceutical company focused on oral T replacement products, released top-line results from its ongoing phase III study of CLR-610, a proprietary oral testosterone (T) replacement product.

In this positive-controlled study, data from the 90-day treatment phase demonstrate that 87% of the 141 men treated with CLR-610 achieved average serum T levels (C-avg) in the normal range (300-1,000ng/dL), the study's primary efficacy endpoint. The C-avg in men treated with CLR-610 was 624 ng/dL. This compares to the 80% of the 146 men in the T-gel comparison arm who achieved C-avg in the normal range. The C-avg in men treated with the T-gel comparison arm was 480 ng/dL.

"We are particularly excited about the significant number of men receiving CLR-610 who achieved normal T levels in this study," said Bela S. Denes, M.D., chief medical officer of Clarus. "Market research shows that men currently being treated for low T with transdermal or injectable products would overwhelmingly prefer an oral option. Thus, we believe CLR-610 will have strong appeal."

The study enrolled 325 men with low serum T (less than 300ng/dL) in 25 sites in the U.S. and five sites in Germany. Men were randomly assigned to receive CLR-610 or T-gel. Primary endpoint of the ongoing study is the percentage of men who achieve normal serum T levels after administration of CLR-610 for 90 days. At least 75% of men on day 90 must had an average serum T in the normal range to meet current FDA efficacy guidance for T replacement products.

Consistent with phase II results, there was no evidence of liver toxicity in men treated with CLR-610 or T-gel.

"The results observed thus far with CLR-610 are very encouraging and the feedback we received from trial participants at UCLA has been extremely positive," added Ronald S. Swerdloff, M.D., chief of the division of endocrinology, department of medicine at the Harbor-UCLA Medical Center and the principal investigator at the LA Biomedical Research Institute on the phase III study. "The convenience of an oral T replacement option is one that I believe patients and their healthcare providers will embrace."