Pharmac knew there were clinical reasons some epilepsy patients would not tolerate a change to their medicines. But the drug buying agency went ahead with a switch that forced more than 10,000 people to change brands of the anti-epileptic drug lamotrigine anyway.
That admission was contained in evidence presented by Pharmac today at the Chief Coroner's Inquest into whether the brand switch had any role in the deaths of six people, who died after changing epilepsy medication.
"Pharmac staff were conscious when negotiating this agreement that there would be some patients who, for clinical reasons, would not be able to change brands of lamotrigine," Pharmac's director of operations manager Lisa Williams said.
She said that was why Pharmac's agreement to allow the generic drug Logem to be the sole form of publicly funded lamotrigine provided for a "specified number of patients" to remain on their original brand of medicine.
Pharmac's specialist neurological committee said in 2019 that the number of patients who would not tolerate the brand switch "would likely be low - less than 100".
Williams said Pharmac aimed to save $30 million over five years with the switch, but had been cautious about the change because previous advice from its Pharmacology and Therapeutic Advisory Committee (PTAC), had warned against it.
"PTAC had historically given advice cautioning against changing patients stabilised on one brand of lamotrigine in 2007 and against brand changes for anti-epileptic drugs more generally in 2009, 2010, 2012 and 2013."
Because of that, Williams said Pharmac was conscious of getting sound clinical advice before making the brand switch.
In 2019, Pharmac received assurance from its specialist neurological committee that it would be safe to make the brand switch.
Williams said Pharmac had then gone to significant lengths to help patients switch brands before the move was fully implemented on October 1, 2019.
This included a five-month transition period, rather than the normal three, and offering patients a free GP visit if they needed it.
Pharmac said it widely distributed information about the change, including on its own website and by engaging with interest groups like Epilepsy New Zealand.
It also held a Facebook "ask me anything" event in June 2019, although "fewer than fifteen" people attended it.
The inquest also heard from the UK-based Jane Hanna OBE, an international expert with 25 years experience in tackling epilepsy deaths.
Hanna told the inquest that changing brands of medication was a known risk factor in epilepsy fatalities.
She said small differences between drugs could make a significant difference to people with epilepsy, as generic equivalent drugs could increase risks to the patient, including fatal seizures.
"Changes in medications three to six months before death, problems with adherence with medication and depression and anxiety are some of the known risk factors associated with epilepsy mortality," Hannah said.
She was also highly critical of Pharmac for a "paternalistic" attitude when determining how much information patients needed about the change.
When Pharmac's special subcommittee considered the brand switch change in February 2019, it said "there was a risk of causing unnecessary anxiety about the change if too much emphasis was placed on the change and that caution should be taken with the amount of information provided to patients upfront."
Hanna said that approach did not align with valuing the lives of people with epilepsy.
"It is a paternalistic approach which has been at the centre of the problem or challenge of dealing with epilepsy death."
The inquest heard that many of those who died did not know about the brand switch and neither did the GPs caring for them.
Even some of those who were aware of the switch did not discuss it with their patients.
Dunedin-based neurologist John Mottershead, who was on the Pharmac subcommittee which considered the brand switch, told the court he did not normally discuss brand changes with his own patients.
"I generally wouldn't do it unless it had been volunteered, or they expressed a brand preference or a problem with a particular brand," he said.
"It's not something that we would have actively sought out."
The UK's medicines regulator - the MHRA, the equivalent of New Zealand's Medsafe - lists lamotrigine in a category of drugs which are too risky for patients to switch brands without a clinical assessment and consultation with the patient.
Hanna recommended that the UK approach be adopted in New Zealand.
Pharmac says Logem is entirely safe, works in the same way as other lamotrigine brands available in New Zealand and that people who have been prescribed the drug should not stop taking it.
The inquest is due to wrap up next week.