Shares of

DUSA Pharmaceuticals

(DUSA) - Get Report

were among the worst-performing health-related stocks Friday, falling 10% after the company posted disappointing second-quarter product sales.

The biopharmaceutical company reported Kerastick sales of 20,172 units, up from 17,910 a year ago, but down significantly from a quarter ago when it sold 28,704 units. During the quarter the company placed 72 BLU-U units. At the end of the second quarter some 1,117 units were in doctor's offices. The company said that its Kerastick sales were hurt by discounting and by the addition of 11 new salespeople to the company's sales force during the first four months of the year. "While we are disappointed with the second quarter sales results, we continue to receive very positive feedback about our therapy from doctors across the country that believe Levulan PDT will become a routine part of standard dermatological practice," the company said. DUSA said that it expects to post full second-quarter results on or before Aug. 9. Shares were trading down $1.03 to $9.10.

Rigel Pharmaceuticals

(RIGL) - Get Report

fell 4% after the company said that it would sell 3.65 million shares at $20.75 a share. The price represents a 4% discount to Thursday's closing price of $21.56. The company granted underwriters an option to buy an additional 547,500 shares to cover over-allotments. The sale is expected to close on July 20. Shares were trading down 77 cents to $20.79.

Shares of

Ivax

( IVX) traded actively after the company's hydrocholorothiazide capsule received final Food and Drug Administration approval. The drug is the generic equivalent of

Watson Pharmaceuticals'

(WPI)

Microzide, which is used for the treatment of hypertension. Ivax said that it would sell the product through its Ivax Pharmaceuticals subsidiary. Shares were recently trading down 6 cents to $22.85.

Keryx Biopharmaceuticals

(KERX) - Get Report

rose 11% after the company priced its 5-million-share stock offering. Keryx said it would sell the shares for $14.05 apiece, resulting in gross proceeds of about $70.7 million. The company also granted underwriters an option to purchase an additional 750,000 shares to cover over-allotments. The offering price was in line with Thursday's closing price of $14.05. Shares were trading up $1.49 to $15.54.

Other health-care volume movers included

Pfizer

(PFE) - Get Report

, down 9 cents to $27.51;

Genzyme

( GENZ), up $3.61 to $68.91;

WebMD

(HLTH)

, up 56 cents to $10.71;

Amgen

(AMGN) - Get Report

, up 6 cents to $70.49;

StemCells

(STEM)

, up 2 cents to $5.84;

UnitedHealth Group

(UNH) - Get Report

, down 83 cents to $50.57;

IMS Health

( RX), down 13 cents to $27.06;

Wyeth

( WYE), up 40 cents to $45.37;

Abbott Labs

(ABT) - Get Report

, up 24 cents to $46.86;

Schering-Plough

( SGP), down 17 cents to $19.93;

Merck

(MRK) - Get Report

, down 8 cents to $31.83;

Johnson & Johnson

(JNJ) - Get Report

, up 38 cents to $64.98; and

Bristol-Myers Squibb

(BMY) - Get Report

, up 6 cents to $25.13.