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The science behind IQOS

Our scientific assessment journey

Scientific program

We have developed a comprehensive step-by-step scientific assessment program. This program is inspired by the practices of the pharmaceutical industry and is in line with the FDA’s 2012 guidance on the assessment of candidate Modified Risk Tobacco products. Our assessment was also conducted according to international standards.

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Is IQOS less toxic?

In laboratory settings, we found that IQOS’ tobacco aerosol is less toxic than cigarette smoke.

Our scientists test our products thoroughly before they go into adult smokers’ hands. Using in vitro* assays in our labs, we assessed the cytotoxicity and genotoxicity of IQOS tobacco aerosol in comparison with the smoke of a reference cigarette designed for research purposes. Taken together, the results of these assays show that IQOS tobacco aerosol is significantly less toxic than the smoke from reference cigarette.

* A test performed in vitro ("in the glass") means that it is done outside of a living organism and it usually involves isolated tissues, organs or cells. They are used to evaluate human specimen (blood, urine, other).

This is just a glimpse of our work. These tests were crucial before we moved on to test IQOS with thousands of adult smokers who voluntarily participated in our clinical study program and ultimately allowed us to commercialize our products.

Clinical studies

Do the significantly lower number and levels of harmful chemicals in IQOS tobacco aerosol also mean lower levels of such chemicals in the body? If you reduce the level of harmful chemicals in IQOS tobacco aerosol, it would make sense that switching completely to IQOS from cigarettes reduces exposure to these harmful chemicals. To prove this, we measured biomarkers of exposure for a number of these harmful chemicals in thousands of smokers who participated in our clinical study program (some switched to IQOS, while others either continued smoking their cigarette brand or quit for the duration of the study).

These studies show that when smokers switch to IQOS, their body absorbs significantly lower levels of harmful chemicals, which in turn results in favorable changes in a number of risk markers selected because of their known association with smoking-related diseases.

IQOS experience

Our clinical study participants who switched to IQOS also report that IQOS provides comparable levels of experience as cigarettes. This supports our view that IQOS has the potential to be an acceptable alternative for adult smokers who would otherwise continue to smoke. Based on all the scientific evidence, we are confident that switching completely to IQOS is less harmful than continuing to smoke cigarettes.

However, and this is important: IQOS is not risk-free and the reduction in risk also depends upon each individual’s smoking history. The absolute best choice remains to quit tobacco and nicotine use altogether. IQOS is not an alternative to cessation. It delivers nicotine, which is addictive.

Long term studies

Once IQOS is available in the market, the research moves from being conducted in a pre-market setting to a real-world post-market setting. There, we look at how the product is being used and by whom in order to complement our pre-market findings and to do our best to identify and prevent use or uptake by unintended audiences. After years of commercialization in many countries, the available data confirms our pre-market observations that IQOS is chosen by adult smokers and there is a relative lack of interest in former and never smokers.

We also monitor reports of health effects now that the product is used by millions of adult users. Long-term studies will eventually help us to evaluate the potential disease–specific risk reduction of IQOS. Gathering data to answer this question takes time, but it’s the right choice. So far, all the data we’ve seen points in the right direction.

The result:

IQOS is a better choice than continued smoking.

The totality of scientific evidence available to-date clearly demonstrates that switching completely to IQOS presents less risk to your health than continuing to smoke cigarettes*.

IQOS is not risk free and delivers nicotine, which is addictive. The best decision any smoker can make is to quit tobacco and nicotine use altogether.
* Source: based on the totality of evidence available for IQOS in comparison with continuing to smoke, which includes data on aerosol chemistry from 10 clinical studies conducted with thousands of participants in the US, Japan and Poland, and data from 18 non-clinical studies.
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This website contains information about our smoke-free products and we need your age to make sure that you are an adult in Lithuania who would otherwise continue to smoke or use nicotine products. Our nicotine and tobacco products are not an alternative to quitting and are not designed as cessation aids. They are not risk free. They contain nicotine, which is addictive. Only for use by adults.