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.

Cortex has inactivated but hasn't formerly withdrawn the IND while it reviews the FDA response but said any resubmission for ADHD is unlikely. The company is also studying CX717 for acute treatment of respiratory depression and for Alzheimer's Disease. Cortex noted that an acute indication requiring a lower dose or an indication with a different risk/benefit profile would be a better fit for the drug. Shares tumbled $1.14, or 63%, to 66 cents.

On the rising side, Novacea ( NOVC) edged up 11 cents, or 1.7%, to $8.60, after initiating a phase II, 56-patient trial for banoxantrone, an investigational anti-cancer prodrug in patients with relapsed or refractory acute lymphoblastic leukemia (ALL), a type of cancer that starts with white blood cells in the bone marrow.

The primary efficacy objective is the response rate over three cycles of the drug, and the secondary efficacy objectives are duration of response and overall survival. The study will also evaluate safety and tolerability.

Also, Momenta ( MNTA) climbed after disclosing top-line results from a phase I study and announcing that it treated the first patient in its phase II study (called the Eminence trial) on the IV formulation of its blood thinner M118. The study is designed to treat patients with stable coronary artery disease who are undergoing percutaneous coronary intervention (PCI). Shares rose 63 cents, or 5%, to $13.08.

Elsewhere, Ariad Pharmaceuticals ( ARIA) entered into a non-exclusive license agreement with cardiovascular device company Icon Medical, to develop and commercialize drug-eluting stents that deliver Ariad's novel mTOR inhibitor, deforolimus, to prevent re-narrowing of arteries after interventions in which stents are used with balloon angioplasty.

Icon is responsible for development and commercialization. Ariad is receiving an equity stake in Icon, up to $27 million in payments based on achievement of certain clinical, regulatory and commercial milestones for two products and royalties on all sales of Icon medical devices that deliver deforolimus. Additional terms weren't disclosed. Ariad shares edged down 12 cents, or 2.3%, to $5.01.