A public outcry has led to the NZ government’s drug funding agency making a partial backdown on a policy that restricted lamotrigine prescriptions to just one generic brand for people with epilepsy.

The country’s drug buying agency Pharmac removed brands including Lamictal from public funding on 1 October and stipulated that patients could access the Mylan-supplied generic Logem.

But the move, which aimed to save the country $30 million over five years, has been accompanied by media reports linking brand switching to breakthrough seizures and possibly three deaths of people with epilepsy.

The switch to a single generic supply of lamotrigine was done with the backing of the drug-funding agency’s neurological expert committee, although the medical regulatory body MedSafe said there were potential safety issues.

The move also triggered concerns from patients and clinicians who said that the 10-20% differences in lamotrigine absorption between generic brands could lead to loss of seizure control for some patients.

“As a neurologist, I’m slightly uncertain about whether the absorption characteristics in the different tablets are going to be exactly the same,” neurologist Dr Peter Bergin told Radio New Zealand.

“The real difficulty is that we won’t know whether people who have seizures have done so because they’ve changed the drug. The reality is that even if someone has been seizure-free for a year, there’s no guarantee they’ll remain seizure-free for the next year,” said Dr Bergin, who is president of Epilepsy New Zealand.

In response to the concerns, Pharmac announced on 15 November that it would ease the criteria for lamotrigine for patients in exceptional circumstances.

“We understand the news of the three deaths of patients taking lamotrigine will concern people. We don’t know if this linked to the brand change – and we don’t want people to stop taking their medication out of fear so we’re making it easier for people to stay on their current brand if their doctor believes it is the right thing for them,” said Dr Ken Clark, PHARMAC’s medical director.

Dr Clark emphasised that Logem had been approved as safe and effective by drug regulators and was widely used internationally including in Australia.