NEW YORK (CNN/Money) - Drug stocks took another hit Friday, a day after a veteran Food and Drug Administration researcher said that five drugs currently on the market needed closer scrutiny for possible safety risks.

Dr. David Graham, speaking before a Senate panel Thursday, highlighted Abbott Laboratories Inc.'s weight-loss drug Meridia, AstraZeneca Plc's cholesterol fighter Crestor, Pfizer Inc.'s arthritis treatment Bextra, Roche's acne drug Accutane and GlaxoSmithKline's asthma drug Serevent.

Shares of Abbott (down $0.57 to $42.80, Research), AstraZeneca (down $0.66 to $39.70, Research), GlaxoSmithKline (down $0.76 to $42.83, Research) and Pfizer (down $0.32 to $27.45, Research) all lost more than 1 percent Friday. Roche stock fell in Zurich.

Graham, associate director for science in the FDA's Office of Drug Safety, told the Senate committee that the five drugs and possibly others on the market needed to be "looked at quite seriously to see if they belonged there."

Graham in August argued after an FDA-sponsored study that Merck's arthritis drug Vioxx posed serious risks for heart attack and stroke, a month before the drugmaker pulled its $2.5 billion drug off the market due to those same risks. The FDA researcher said Thursday that senior FDA officials tried to suppress his views.

"David Graham was the FDA researcher who had questioned Vioxx's safety before it was recalled, so a list of drugs he's also concerned about is going to be taken quite seriously,'' said David Moskowitz, an analyst at Friedman, Billings, Ramsey & Co.

A top official at the FDA's Office of New Drugs disagreed with Graham's views on the five drugs he cited during Thursday's hearing on Capitol Hill.

"I do not have reason to believe that set of five drugs is specifically more concerning,'' Dr. Sandra Kweder, deputy director of the Office of New Drugs, told the Senate Finance Committee hearing.

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Pfizer's Bextra is in the same class of drugs as Vioxx, which was recalled Sept. 30 after a company study showed it doubled heart attack and stroke risk.

The FDA is planning to look at the entire family of Vioxx-type drugs at an advisory committee meeting next year, including Pfizer's older Celebrex arthritis treatment.

Shares of Merck (down $0.26 to $27.10, Research) also fell Friday. Its stock has lost about 40 percent since its Vioxx recall.  

-- Reuters contributed to the story