Biogen Idec files NT 10-Q to explain late filing of 10-Q 41.54 -0.31 : From today's NT 10-Q: "The registrant was not able to timely file its quarterly report on Form 10-Q for the fiscal quarter ended June 30, 2006 because it had not completed the preparation of its financial statements for the period. On August 10, 2006, the registrant filed its quarterly report on Form 10-Q for the fiscal quarter ended June 30, 2006..."

GeoPharma (GORX) sank 12.5% to $3.08 following its earnings report Thursday. The company earned $195,000, or 2 cents a share, in the quarter compared with $515,000, or 5 cents a share, a year ago. Excluding stock options expenses, the company earned 6 cents a share. Revenue reached $14.4 million, up 22.3% from a year ago.

Oscient Pharmaceuticals (OSCI) got a boost after the company agreed to allow Abbott (ABT) to market its Factive bronchitis drug in Canada. Specific financial terms were not disclosed. Shares were up 2.2% to $1.20.

Advancis Pharmaceutical (AVNC) rose after the company reported positive trial results on its anti-infective drug amoxicillin Pulsys. The stock was higher by 43.9% to $4.49.

Tenet Healthcare's (THC) shares jumped following its quarterly report after the close of trading Wednesday. While the company reported a wider loss of $398 million, or 85 cents a share, in the second quarter, compared with a loss of $33 million, or 7 cents a share, a year earlier, excluding hefty one-time charges, earnings beat analysts' estimates. Tenet had adjusted earnings of 4 cents a share, compared with 3 cents analysts were expecting. Shares were up 12.5% to $6.56.

Among other health stocks on the move were Dynavax Technologies (DVAX) , up 9.1% to $4.33, Xenoport (XNPT) , up 8.2% to $18.15, Cytokinetics (CYTK) , gaining 7.6% to $5.81, and Medicure (MCU) , higher by 6.6% to $1.62. Celgene (CELG) was down 3.4% to $41.37, EP Medsystems (EPMD) fell 8.7% to $1.37, and Allied Healthcare International (AHCI) lost 13% to $2.