NEW YORK (TheStreet) -- Shares of Alcobra (ADHD) were dropping 56.82% to $2 on heavy trading volume mid-Thursday morning after the company said late yesterday that it received verbal notice from the FDA to hold its MEASURE study of MDX, an ADHD treatment for adults.

The Israeli biopharmaceutical company has not been given written notice to place the trial on clinical hold, but Alcobra said it will work with the FDA to resolve any issues with the study.

Cantor Fitzgerald maintained its "buy" rating and $16 price target on the stock today following the announcement.

"We have liked the reworked phase III MEASURE study, which has been a key component of our investment thesis," the firm said.

Any issues the FDA has with preclinical information "could be resolved," Cantor added.

Although Alcobra shares are likely to face pressure today, the firm said, Cantor noted that it is positive on the "risk/reward scenario" on the stock.

More than 2.03 million shares of Alcobra have traded so far today vs. the 30-day average volume of about 114,000 shares.

Image placeholder title