A few biotech stocks took a tumble Tuesday amid earnings, regulatory setbacks and a management shakeup.

In earnings, medical technology company Biolase Technology ( BLTI) reported a net loss of $3.1 million, or 15 cents a share, vs. a loss of $1 million, or 4 cents a share, in the 2006 quarter. The company reported net revenue of $12.8 million, compared to $17.1 million in the year-ago period. Analysts surveyed by Thomson Financial had expected a loss of 2 cents a share on revenue of $18.3 million.

Additionally, the company said that CEO Jeffrey Jones is leaving the company immediately, and Federico Pignatelli, an independent director, will serve as interim CEO while a replacement is sought. Keith Bateman, executive vice president of global sales and marketing, also is leaving immediately and the company is searching for his replacement. Shares gave up $2.45, or 45%, to $2.97.

Also, Albany Molecular Research ( AMRI) missed on earnings Tuesday and fell $5.59, or 32%, to $11.82. The company reported adjusted earnings of $2 million, or 6 cents a share, vs. $1.4 million, or 4 cents a share in the year-earlier period. Revenue came in at $47.56 million, vs. $44.2 in the 2006 quarter. But analysts surveyed by Thomson Financial expected 9 cents a share on revenue of $48.3 million.

Then Anika Therapeutics ( ANIK) reported earning $1.8 million, or 16 cents a share, compared with $1.3 million, or 12 cents a share, for the same period last year. The company reported product revenue of $7.3 million vs. $5.5 million in the 2006 period. The company also said it's in negotiations to terminate its license and supply agreements with Galderma Pharma for the Elevess family of products.

Anika's injectible dermal filler Elevess has marketing approval in the U.S. and in Europe for improving the appearance of wrinkles and scars, and for lip augmentation. Anika will now be seeking a new distribution partner to launch it. Shares fell $3, or 16.8%, to $14.89.

Elsewhere GPC Biotech ( GPCB) and Spectrum Pharmaceuticals ( SPPI) said Monday after close that an American Arbitration Association panel appointed to resolve a dispute over claims raised by Spectrum Pharmaceuticals and counter claims by GPC Biotech dismissed all claims.

The dispute related to the co-development license for prostate cancer drug satraplantin. Spectrum demanded arbitration based on being excluded from almost $70 million in sublicense income that GPC Biotech received and to address other non-monetary material violations of its license agreement. GPC Biotech counterclaimed and demanded a royalty-free license.

GPC was trading up 95 cents, or 19.9%, at $5.73, while Spectrum was down 27 cents, or 7%, to $3.59.

Also on the decline, Momenta Pharmaceuticals ( MNTA) plummeted $7.52, or 56.2%, to $5.86, after it announced the Food and Drug Administration rejected its abbreviated new-drug application for a generic form of Lovenox, a blood clot treatment and preventive.

Momenta Pharmaceuticals and Albany Molecular weren't enough to weigh down the Nasdaq biotechnology index, of which they're components. The index was up 2.83, or 0.3%, to 880.34.