UPDATE 1-U.S. FDA releases initial review of Philip Morris' iQOS device

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Jan 22 (Reuters) - An electronic tobacco product made by Philip Morris International Inc that heats rather than burns tobacco contains lower levels of harmful and potentially harmful compounds than cigarettes, a preliminary review by the U.S. Food and Drug Administration (FDA) concluded on Monday.

Laboratory data showed that the aerosol produced by the product, iQOS, can damage cells and affect human tissue, but that the effects "are generally less severe and observed at much higher concentrations," in a reference to cigarette smoke.

The reviewers said full results from a pending study would provide more information about the carcinogenic potential of iQOS, but the results are not expected to become available until later this year.

The review comes two days before a meeting of outside advisors to the FDA who will discuss the product and recommend whether it should be allowed on the market. The panel will also decide whether the company should be allowed to claim iQOS is less harmful than cigarettes.

The FDA is not obliged to follow the recommendations of its advisors, but typically does.

The FDA reviewers found that by some respiratory and cardiovascular measures, iQOS aerosol exposure produced less damage than cigarette smoke. But they also noted there was little difference seen in the development of certain potentially pre-cancerous lesions in the respiratory tract.

Overall, data from the nonclinical studies suggest that iQOS aerosol has lower toxic potential than cigarette smoke under the conditions used in the tests and for the non-cancer conditions measured.

But they said it is "unclear how the effects observed in treatment groups exposed to iQOS aerosols translate to a potential risk reduction for noncancer-related effects when chronically used by humans."

(Reporting by Toni Clarke in Washington; editing by G Crosse)