Updated from 3:07 p.m.

Shares of

KV Pharmaceutical

(KVA)

were among the worst-performing health-related stocks Wednesday, falling 17.8% after the company warned that fourth-quarter results would be well below year-ago levels.

The company now believes it will post a modest fourth-quarter profit or a small loss. Sales, meanwhile, are expected to be about $72 million. Analysts polled by Thomson First Call had been expecting a profit of 26 cents a share on sales of $94.5 million. KV blamed the shortfall on delayed approvals for certain generic products, increased headcount related to Ther-Rx sales, a temporary interruption in the supply of the company's PrimaCare One product, lower volumes and price erosion relative to certain generic/nonbranded products, and the timing of certain trade show orders. Shares traded down $4.30 to $19.92.

Delcath Systems

(DCTH)

rose 33.6% after the company said its system for delivering high-dose chemotherapy to specific organs and body regions received fast-track status from the Food and Drug Administration for use in treating metastatic melanoma in the liver with melphalan, an approved anticancer agent. Shares traded up 94 cents to $3.57.

Shares of

Salix Pharmaceuticals

(SLXP)

rose 6% after the company posted first-quarter earnings that beat forecasts. The specialty pharmaceutical company earned $3.4 million, or 9 cents a share, on sales of $28.8 million. Analysts were expecting earnings of 7 cents a share on sales of $28.8 million. A year ago the company posted a loss of $2.4 million, or 7 cents a share, on sales of $19.9 million. Looking ahead, Salix forecast sales of $150 million to $1.55 million and earnings of at least 60 cents a share. Analysts are expecting earnings of 63 cents a share on sales of $144.7 million. Shares traded up 88 cents to $15.58.

ArthroCare

(ARTC)

rose 14.3% after the company posted first-quarter results that beat expectations. The company earned $3.2 million, or 12 cents a share, on sales of $49.7 million. Excluding items, the company would have earned 16 cents a share. Analysts were expecting earnings of 14 cents a share on sales of $48 million. A year ago the company earned $1.6 million, or 7 cents a share, on sales of $35.6 million. Shares traded up $4.08 to $32.65.

Other health care volume movers included

Elan

(ELN)

, up 52 cents to $7.42;

Pfizer

(PFE) - Get Report

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, up 18 cents to $27.65;

Amgen

(AMGN) - Get Report

, up 39 cents to $61.42;

Arena Pharmaceuticals

(ARNA) - Get Report

, up 52 cents to $6.49;

Merck

(MRK) - Get Report

, down 38 cents to $33.50;

Vertex Pharmaceuticals

(VRTX) - Get Report

, unchanged at $13.40;

Johnson & Johnson

(JNJ) - Get Report

, up 22 cents to $67.95;

Schering-Plough

(SGP)

, up 10 cents to $20.39; and

Genentech

(DNA)

, up 22 cents to $74.60.