FDA Extends Authority to e-Cigarettes: Implications for Smoking Cessation? on July 27, 2016

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FDA Extends Authority to e-Cigarettes: Implications for Smoking Cessation?

On August 8, a final rule from the US Food and Drug Administration (FDA) goes into effect that tobacco control experts say could dramatically change the status of e-cigarettes in this country. The rule extends the agency’s regulatory authority to all tobacco products, including e-cigarettes, and requires manufacturers to report product ingredients and undergo the agency’s premarket review to receive marketing authorization.

The move is intended to “improve public health and protect future generations from the risks of tobacco use,” the FDA said in a statement. Tobacco-control experts lauded the FDA for restricting e-cigarette use in adolescents: the rule makes it illegal for the products to be sold in person or online to people younger than 18 years. Use of e-cigarettes has skyrocketed among adolescents, and there’s some early evidence that it may lead to cigarette smoking in this demographic. 

Yet some experts have expressed misgivings about unintended consequences of tight regulations that could potentially block cigarette smoking cessation efforts by adult e-cigarette users.

The concerns bring to light the health conundrum presented by e-cigarettes: do these devices deliver a recreational drug or a medicine? If they can do both, which some experts argue is likely the reality, how do health agencies and health care professionals balance the risks with the benefits?

POPULARITY GROWS
According to the first estimates from a nationally representative household interview survey, more than 12% of US adults have tried an e-cigarette, while less than 4% are current users. Since they entered the US market in 2007, e-cigarettes, which typically contain nicotine in varying dosages, have become increasingly popular among cigarette smokers trying to quit or reduce their harm.

“Survey after survey shows [that] when you ask people who have tried e-cigarettes what [they tried] for, one big chunk says to quit smoking and another big chunk says to reduce smoking,” said Jonathan Foulds, PhD, professor of public health sciences and psychiatry at Penn State College of Medicine’s Cancer Institute.

There aren’t robust data yet on how many people in the United States are switching from cigarettes to e-cigarettes to help them quit. However, in the United Kingdom, where e-cigarettes are already a widely accepted quit-smoking tool, there’s a clear preference for the devices over traditional nicotine replacement therapy (NRT).

The trend is perhaps unsurprising, considering that puffing on an e-cigarette mimics smoking far more closely than wearing a nicotine replacement patch or chewing nicotine replacement gum.

“We know that [e-cigarettes] are products that smokers seem more interested in buying than nicotine replacement products that are FDA-approved cessation aids,” said Nancy Rigotti, MD, director of the Tobacco Research and Treatment Center at Massachusetts General Hospital.

While it’s clear that many smokers want to use e-cigarettes to quit, questions about safety and efficacy continue to loom large.

INVESTIGATING TOXICITY

Smoke from combustible cigarettes contains upwards of 7000 chemicals, including dozens of carcinogens, compared with a handful of chemicals in the vapor produced by e-cigarettes. Most of the toxicants released from tobacco combustion aren’t present in e-cigarette vapor, said Maciej Goniewicz, PhD, PharmD, assistant professor of oncology at Roswell Park Cancer Institute in Buffalo, New York. Goniewicz is currently investigating e-liquid flavorings, many of which have never been studied for inhalation toxicology.

The main group of toxicants in e-cigarette vapor appears to be carbonyl compounds, including the human carcinogens formaldehyde and acetaldehyde, Goniewicz said. But urine levels of metabolites from certain toxicants and carcinogens have been found to be significantly lower in e-cigarette smokers than in smokers. 

“That’s the kind of evidence that makes [researchers] feel it’s reasonable to make… an educated guess that e-cigarettes are probably significantly less harmful than cigarettes,” Foulds said.

Foulds was a member of an international expert panel convened by DrugScience (formerly the Independent Scientific Committee on Drugs), a UK-based research group, that investigated the relative harm of nicotine-containing products. Looking at 14 criteria, including morbidity, mortality, dependence, and injury, the panel concluded in 2014 that cigarettes are more harmful than e-cigarettes 

“Based on the results that we have and that have already been published, even in a worst-case scenario… compared to tobacco cigarettes, electronic cigarettes are still less toxic,” Goniewicz said.

Rigotti agreed that the relative risk of e-cigarettes is lower. “[I]t’s almost certain that using them will be safer than continuing to use cigarettes,” she said, although she noted that “we also don’t know that they’re harmless.”

“The big concern, and I share this concern, is the long-term effect of using electronic cigarettes,” Goniewicz said. Their potential harm may become apparent in people who transfer their nicotine addiction from combustible cigarettes to e-cigarettes instead of weaning themselves off nicotine altogether—a phenomenon that is almost certain to occur in some exsmokers, Foulds said.

Naturally, understanding the potential long-term health effects of vaping will take many years of study. Those investigations will be made difficult by the relatively small numbers of regular e-cigarette users and the almost nonexistent numbers of regular users who never smoked.

“It’s really hard to separate the effects of electronic cigarette use versus a history of previous smoking,” Goniewicz explained.

EVALUATING EFFICACY
Meanwhile, researchers are locking horns over whether e-cigarettes can actually help people quit smoking.
Researchers at the University of California, San Francisco (UCSF), ignited debate with a recent systematic review and meta-analysis that included the only 2 randomized trials on the subject, as well as 15 cohort and 3 cross-sectional studies. They concluded that the odds of quitting smoking were 28% lower in adults who used e-cigarettes compared with those who did not use e-cigarettes.

“There’s been a fair amount of discussion and vitriol about [this analysis],” Rigotti said.

Peter Hajek, PhD, director of the tobacco dependence research unit at the Wolfson Institute of Preventive Medicine in London, pointed out that the studies included in the UCSF analysis primarily compared smokers who tried vaping but continued to smoke with smokers who did not try vaping. This meant that smokers who tried vaping and successfully stopped smoking were excluded. “The paper took studies that contained no useful information on whether vaping helps smokers quit and misreported them as if they were showing that vaping undermines quitting,” he said.

Hajek added, “population data show that e-cigarettes have helped a large number of smokers quit, but there have been only a few experimental studies so far.”

In fact, the 2 randomized clinical trials looking at the effectiveness of e-cigarettes for smoking cessation that have been published to date both reported only modest cessation rates with e-cigarette use relative to placebo.  In the larger Lancet study, led by researchers in New Zealand, quit rates at 6 months for both e-cigarettes (7.3%) and nicotine patches (5.8%) were disappointingly low compared with placebo e-cigarettes (4.1%).

Foulds pointed out that this study, although a good trial, used a first-generation “cigalike” device that delivered low levels of nicotine. A problem with the published studies is that they haven’t taken into account a few crucial factors, such as device design and regularity of use, he said. Newer-generation e-cigarettes, which quickly deliver a high dose of nicotine, appear to help people quit more effectively than cigalikes, and people who use e-cigarettes every day are more likely to quit smoking than nondaily users.

“I think there are very important factors that probably affect the success rate [of] quitting with electronic cigarettes, and I think we’ve just started to understand the predictors of successful quit attempts with the devices,” Goniewicz said.

Contributing to the dearth of clinical trials assessing the efficacy of e-cigarettes for smoking cessation is the FDA’s requirement for an Investigational New Drug (IND) application though its Center for Drug Evaluation and Research, which researchers say is a prohibitively time-consuming and expensive process.

As a result, “it’s been virtually impossible in the United States to do [such] research,” Rigotti said.
For this reason, US-based researchers are eagerly awaiting a standardized electronic cigarette in development through the National Institute on Drug Abuse. The project will provide researchers with the device data the FDA requires to evaluate an IND application.

CONCERNS OVER REGULATION
Given the new FDA rule, the public may also feel the pinch. A costly premarket application process through the agency’s Center for Tobacco Products (CTP) could lead to consolidation of the e-cigarette market, pushing out smaller manufacturers and leaving only the largest players—mainly tobacco companies—still standing. As a result, there is concern that smokers who want to use e-cigarettes to quit will have fewer choices.

“Because I think [e-cigarettes] may be valuable for people that can’t stop smoking with other methods, I want to make sure that they’re still available,” Rigotti added.

There’s another possible fallout: e-cigarette models from tobacco companies tend to be “closed-system” devices that don’t allow for user. Shu-Hong Zhu, PhD, director of the Center for Research and Intervention in Tobacco Control at the University of California, San Diego, School of Medicine, has found that smokers prefer open systems when they try to quit smoking, and those who use open systems are more likely to succeed in quitting. “If the [FDA] regulation dramatically limits the availability of open systems, which allows greater customization by the user… the associated benefit to smoking cessation could be reduced,” Zhu said in an email.

At a press conference in May, FDA officials indicated they will weigh the net effects of e-cigarettes on a population level as they decide how to implement the agency’s new authority over the products. “We’re trying to maintain an open mind here,” CTP director Mitch Zeller, JD, said at the meeting. According to an FDA spokesperson, the CTP has supported or is currently supporting more than 85 research projects addressing e-cigarettes, including investigations around design, constituents, toxicity, addiction, and health consequences.

Earlier this year, the Tobacco Advisory Group of the Royal College of Physicians published a report that stated, “in the interests of public health, it is important to promote the use of e-cigarettes, NRT, and other nontobacco nicotine products as widely as possible as a substitute for smoking in the United Kingdom”.

The US Preventive Services Task Force disagrees. A draft recommendation statement from the group concluded that “the current evidence is insufficient to recommend electronic nicotine delivery systems (ENDS) for tobacco cessation”.

Clinicians in the United States—even those who believe e-cigarettes could help people quit smoking—also aren’t ready to make the leap to recommending e-cigarettes as a first-line smoking cessation therapy. “We have other things that are FDA-approved that we know are safe and effective to help you quit, and so I encourage smokers to use those other products first,” Rigotti said.

Foulds agreed: “Clinicians should use FDA-approved smoking cessation medicines, but if somebody says ‘I’ve tried all that; I really want to try an e-cigarette,’ I don’t think we should say, ‘No, you must not: they’re equally as harmful as cigarettes.’ Because that’s simply not true.”

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