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Repros plunges on testosterone drug study delay

NEW YORK (AP) -- Shares of Repros Therapeutics Inc. plunged 40 percent Monday after the company said that results from a study of its testosterone drug Androxal will be delayed because it is removing some patients from the trial.

Repros said men at one testing site had lower starting sperm counts and testosterone levels than other patients in the study, and they appeared to respond as well or better to Androxal than other patients. The Woodlands, Texas, company said it decided to remove those 40 patients from the trial and will replace them with patients who were going to participate in a second study of Androxal. There were a total of 151 patients in the trial.

Repros is studying Androxal as a treatment for secondary hypogonadism, a condition in which the testes don't produce enough testosterone. The company said it now expects to report data from the study during the third quarter instead of the second quarter. It still expects to file for marketing approval of Androxal in mid-2014.

Shares of Repros lost $7.50, or 40.3 percent, to $11.11 on Monday. The shares had been trading at their highest price in three and a half years, peaking at $19.12 on Thursday.

Repros does not have any approved drugs. It is also studying Androxal as a treatment for diabetes and is researching a drug called Proellex as a treatment for uterine fibroids and endometriosis.