Updated from 2:31 p.m. EDT

Shares of Intuitive Surgical ( ISRG) were among the best-performing health care and pharmaceutical stocks Thursday, after the company received Food and Drug Administration clearance for its da Vinci surgical system.

The system will be used to perform coronary anastomosis during cardiac revascularization. This indication broadens the use of the system and allows surgeons in the U.S. to perform coronary artery bypass surgery with small incisions. The da Vinci system had already received FDA clearance for other intracardiac procedures. Shares of Intuitive Surgical traded up 72 cents, or 4%, to $18.80.

Cantel Medical ( CMN) rose after its subsidiary, Minntech, received Environmental Protection Agency clearance for the use of its Minncare cold sterilant. In its liquid form, the cold sterilant is used to disinfect ultrapure water production and distribution systems used by kidney dialysis centers, pharmaceutical manufacturing companies and the microelectronics industry. Shares of Cantel Medical traded up $1.53, or 6.2%, to $26.11.

Shares of Power3 Medical Products ( PWRM) rose after the company secured the rights to an early-detection breast cancer test. The technology was codeveloped with the University of Texas M.D. Anderson Cancer Center. Shares of Power3 traded up $1.36, or 31.1%, to $5.74.

Tanox ( TNOX) traded down modestly after the company announced it enrolled its first patient in a phase II clinical trial evaluating the safety and efficacy of Xolair in patients suffering from peanut allergies. The drug was codeveloped with Genentech ( DNA) and Novartis ( NVS). The peanut allergy trial will enroll 150 patients and last 38 weeks. Peanut allergy is the most common food allergy in the U.S. Shares of Tanox traded down 22 cents, or 1.3%, to $16.89.

Despite posting strong second-quarter financial results, shares of Genentech sold off Thursday in active trading. The company reported a pro forma profit of 19 cents a share on sales of $1.128 billion . Analysts polled by Thomson First Call had expected it to earn 19 cents a share on sales of $1.06 billion. A year ago, it earned 16 cents a share on sales of $799.7 million. Strong sales of its Avastin cancer-treatment drug propelled the second-quarter sales gain. Shares of Genentech traded down $1.90, or 3.5%, to $52.

Other health care volume movers included Pfizer ( PFE), up 22 cents to $33.94; Schering-Plough ( SGP), up 20 cents to $17.82; Amgen ( AMGN), down 57 cents to $53.32; and Johnson & Johnson ( JNJ), up 23 cents to $54.76.