A Cleveland Clinic researcher bought 9,000 shares of Quigley Corp. stock before publishing the results of a study last summer that found Quigley's zinc lozenges were effective in reducing symptoms of the common cold, which caused the stock's price to soar.

Last week the researcher, Michael Macknin, sold his remaining stock in Quigley, which, along with a previous sale of stock last fall, gave him a profit of $144,000, he said. Company disclosures of the stock sale, at a time when the company's product, Cold-Eeze, is selling briskly, have focused attention on Macknin and whether his stock transactions represented a conflict of interest or violated securities law.

Macknin and his lawyers, as well as spokesmen for the Cleveland Clinic, say he did nothing wrong and that he checked with his lawyer and with the clinic's ethics committee before acquiring the stock, 18 months before the results of the study were made public.

"Macknin bought the stock at the market price from the company with everybody's knowledge and after obtaining opinions from both the clinic and from his own personal counsel," said Sheldon Berns, a lawyer whose Cleveland firm, Kahn, Kleinman, Yanowitz & Arson, represents Macknin. "There's no insider trading here at all. That's not even an issue."

Berns also said the stock purchase did not influence Macknin's scientific judgment because "he had already finished the study when he bought the stock. The study was participated in by people who had no stock." The study and its conclusions also were examined by a peer review board at the Cleveland Clinic and by the Annals of Internal Medicine, the journal that published it, Berns said.

After publication of the favorable study, the product's sales took off and Quigley's stock price soared. The stock closed yesterday at $10, down $1.50, in Nasdaq Stock Market trading.

In an interview yesterday, Macknin defended the stock transactions and the efforts he made to ensure that no one involved with the study objected to the purchase.

Harvey Pitt, a Washington securities lawyer who was formerly general counsel of the Securities and Exchange Commission, said though he doesn't know the details of Macknin's trading, that it appears to him that Macknin broke no laws because he bought the shares from the company, whose executives knew about the study.

Pitt said that buying in the open market, where investors did not know about the study's positive results, would have been a different matter because it could have been interpreted as an insider trading violation of securities law.

In November 1994, Macknin finished his study and "unblinded" it, meaning he discovered for the first time who in the study used the zinc lozenges and who used placebo lozenges. The results were promising, showing that in 100 people the lozenges appeared to reduce cold symptoms and duration by 42 percent. Over the next 18 months, until the study was published, he said it would have been impossible to alter the results because they were being reviewed by colleagues.

Macknin bought 9,000 Quigley shares in December 1994 and January 1995 for $10,000. In July 1996, the results of the cold study were published. In the following months, the price rose, peaking at $31 on Jan 10. (It split 2 for 1 last week.)

Last August, Macknin sold 4,000 of his shares for $14,000. Last Friday, Macknin sold his remaining 5,000 shares for $140,000.

Separately, securities regulators are investigating trading in Quigley stock, after the company complained that false information about the firm was being disseminated to investors.

One leading ethics expert said Macknin's stock transactions are troubling, even if legal.

"It's safe to assume the prospect of buying stock didn't influence him, but the appearance will surely influence others to be skeptical of the research and of the status that researchers have as insiders in the markets," said Arthur Caplan, director of the Center of Bioethics at the University of Pennsylvania. "It is crucial that research, particularly regarding health, be seen as credible." AS THE STUDY UNFOLDS WEEKLY CLOSING PRICE Nov. 1994: Macknin "unblinds" his study, finding out who used the zinc lozenges and who used placebos. Dec. 1994- Jan. 1995: Macknin buys 9,000 shares of Quigley from the company. July 1996: Results of the study are published. Between Aug. 1996 and Jan. 24, 1997, Macknin sells his shares, netting a profit of about $145,000 SOURCE: Bloomberg News