Clinical trial news burned a few biotech stocks Thursday, while brighter trial updates kept others on higher ground. NPS Pharmaceuticals ( NPSP) gave up $1.50, or 27%, to $4.17 after its drug for short bowel syndrome failed to meet its goal in a phase III study. Specifically, the goal was a reduction in parenteral nutrition (being fed intravenously) of at least 20%. The lower-dose group did show a statistically significant reduction compared with placebo, but according to the study design, the high-dose group needed to show statistical significance before the results for the low-dose group could be considered. The company said it will meet with the Food and Drug Administration to discuss the results. Also, CuraGen ( CRGN) said its velafermin for the prevention of mouth ulcerations in patients undergoing chemotherapy treatment failed a phase II clinical trial, and it is discontinuing its development. The company is now focusing on belinostat in phase II clinical trials for solid tumors and malignancies. Shares fell 48 cents, or 33%, to 98 cents. NPS and CuraGen both tugged at the Nasdaq biotechnology index, which was down $2.15, or 0.2%. Small-cap Cortex Pharmaceuticals ( COR) crashed after reporting that the FDA sent a final rejection to the company's investigational new-drug application (IND) to study its CX717 in a Phase IIb study in attention deficit hyperactivity disorder, based on results of animal toxicology studies that Cortex filed.