Health indices were flat Thursday, balanced by stocks moving on merger updates and data divulgence.

Bioenvision

( BIVN) fell 3% after

Genzyme

( GENZ) reaffirmed its offer price of $5.60 per outstanding share to purchase Bioenvision. On Oct. 4, Bioenvision shareholders will vote on the merger.

Genzyme, which already owns all of the company's preferred stock and 22% of the outstanding shares, said in a press release Thursday that if it doesn't garner the majority support from shareholders for the merger, it's committed to playing an active and constructive role as a significant long-term shareholder of Bioenvision.

Genzyme edged down just 31 cents, or 0.5%, to $62.82, and Bioenvision fell 17 cents, to $5.26.

Wednesday after close, biopharmaceutical company

Parexel International

(PRXL)

said it completed its acquisition of Taiwan-based Apex International Clinical Research and now anticipates consolidated service revenue between $203 million and $210 million in the first quarter of 2008 and between $875 million and $910 million for fiscal 2008.

The company previously predicted between $200 million and $210 million for the quarter and between $855 million and $885 million in 2008. Parexel gained $1.42, or 3.5%, to $41.84 Thursday.

Another winner --

MGI Pharma

( MOGN) -- garnered $1.35, or 5.1%, to $27.86, after saying it submitted to the Food and Drug Administration a new-drug application for its Aquavan Injection for use as a sedative-hypnotic agent in patients who are having brief surgical or diagnostic procedures. MGI said that the application comprised data from 21 clinical studies, including 1,611 subjects.

Meanwhile, other companies got a boost of from clinical data.

Introgen Therapeutics

(INGN) - Get Report

said that an analysis of data from multiple phase II studies shows a statistically significant correlation between the abnormal p53 biomarker and how tumors respond to Advexin in patients with head and neck, lung, prostate and LiFraumeni Syndrome cancers. Shares rose 4 cents, or 1%, to $4.21.

Introgen Therapeutics and MGI Pharma are both components of the Nasdaq biotechnology index, which was up 0.5, or 0.1%, to 858.71.

Also,

Pharmacopeia

( PCOP) said a phase I trial confirmed the ability of PS433540, a potential treatment for hypertension and diabetic nephropathy, to block the angiotensin II (AII) response in healthy volunteers, which the company noted is a strong indication that the agent can be expected to lower blood pressure in hypertensive patients.

The study showed that all doses of PS433540 compared with placebo produced a statistically significant inhibition of the expected (AII-induced) increase in blood pressure, and the 250 mg and 500 mg doses PS433540 were at least as effective in blocking the AII response as irbesartan, a leading angiotensin receptor blocker for the treatment of hypertension. Pharmacopeia shares rose 40 cents, or 7.2%, to $5.99.

Elsewhere on Thursday, federal prosecutors said four companies have agreed to pay a total of $311 million to settle government claims under the anti-kickback statute and the civil federal False Claims Act.

Zimmer Holdings

(ZMH)

agreed to pay $169.5 million,

Johnson & Johnson

(JNJ) - Get Report

will pay $84.7 million, Smith & Nephew $28.9 million, and Biomet $26.9 million.

A fifth company,

Stryker

(SYK) - Get Report

, didn't enter a civil settlement and hasn't been given any release from civil liability nor any release from the U.S. Department of Health and Human Services, but did agree to be monitored.

Zimmer rose 1.3% to $82.21; J&J edged up 0.2% to $65.54; and Stryker climbed 1.4% to $68.88.