Varenicline planned for return but ‘not before’ end of 2024, says manufacturer

Smoking cessation therapy varenicline (Champix; Pfizer) will be reintroduced for patients, but is not planned for resupply before the end of 2024, the manufacturer has told The Pharmaceutical Journal.

Varenicline, a nicotine receptor partial agonist, was a first-line treatment for smoking cessation until it was recalled by Pfizer in October 2021, owing to the presence of unacceptable levels of nitrosamine compound N-nitroso-varenicline, a probable human carcinogen​.

Bupropion (Zyban; GSK) was then withdrawn in December 2022 owing to similar concerns, leaving nicotine replacement therapy (NRT) as the only available pharmacological option for smoking cessation in the UK.

In April 2023, then pharmacy minister Neil O’Brien said the government was working with medicine suppliers to ensure supply of smoking cessation aid varenicline in England, as part of wider plans for the country to become smoke free by 2030.

At the time, O’Brien said: “Some of the most cost-effective treatments that we have are not currently available in England. We are working closely with suppliers to give access to prescribers, to put licensed medications in the hands of those who would benefit the most from them.

“For example, ensuring the availability of proven smoking cessation medicines, such as varenicline and cytisine. We have been working urgently with businesses to unblock supply chain problems to support more people who want to quit.”

In July 2023, the European Medicines Agency published updated guidance on nitrosamine impurities, which included limits for acceptable daily intake of nitrosamine, resulting in the return of bupropion in October 2023.

Distributor Consilient Health then announced in December 2023 that cytisine, a popular smoking cessation drug in Europe, was to be made available in the UK from January 2024.

Commenting on the return of varenicline, Darush Attah-Zadeh, clinical fellow respiratory pharmacist at North West London Integrated Care Board, and co-chair of the Taskforce for Lung Health medicines optimisation working group, said: “It’s good news from Pfizer that a resupply is in motion of a much-needed medicine to help treat tobacco dependence.

“It will be three years a void has been left without this effective, well tolerated treatment. I certainly miss it in clinical practice.”

Attah-Zadeh said that varenicline is often available via patient group directions, but this is not the case for cytisine or buproprion.

“The sooner this happens the better,” he added.

According to a population study in England, published on 30 April 2024 in Addiction, researchers estimated that a continued absence of varenicline may result in around 8,400 fewer people quitting smoking for at least six months, and around 1,890 more avoidable deaths each year.

Olivia Bush, NHS strategic lead at the charity Action on Smoking and Health, said: “It is concerning to hear of further delays to the supply of generic varenicline to the UK market.

“Current evidence shows that this will mean fewer people quitting smoking. Ensuring that smokers can access treatments that will improve quitting should be a high priority for local government and NHS services, given the profound impact smoking has on people’s healthy life expectancy,” she added.

“This should include vaping products, shown to be more effective than NRT, as well as accelerating access to a drug new to the UK market, cytisine. When generic varenicline is available in the UK, prescribers should ensure that their patients can get access.”

A spokesperson for the Department of Health and Social Care said a decision to reintroduce varenicline would be a commercial decision for the manufacturer, but added: “We continue to work closely with the pharmaceutical industry to ensure varenicline is made available at the first possible instance, as long as it is safe to do so.”