A cystic fibrosis drug dubbed by doctors as the “holy grail” can cause mood swings, behavioural problems, insomnia and rumours of suicide in children as young as three, disturbing research has revealed.
The drug, Kaftrio, which was approved for full use on the NHS last month, relieves the worst symptoms of the genetic disease and is expected to dramatically improve life expectancy.
But a new study, published last week in The Lancet, offers clear evidence that the drug can affect mental health. Researchers administered doses of the drug to 197 children aged between two and five. After a month, 93 of them (47 percent) suffered sudden and abnormal changes in behaviour.
One third developed attention deficit hyperactivity disorder (ADHD), which causes poor concentration, irritability and impulsive behaviour. Others became aggressive. One in ten developed an “abnormal sadness” and one had suicidal thoughts. These changes persisted in 58 of the 93 children and stopping treatment led to an “immediate recovery of symptoms”.
A cystic fibrosis drug dubbed by doctors as the “holy grail” can cause mood swings, behavioural problems, insomnia and rumours of suicide in children as young as three, disturbing research reveals (file image)
It is not clear why the drug might cause mental health problems or who might be most affected.
The French scientists behind the Lancet study speculate that it may alter the balance of brain chemicals involved in feelings of anxiety and depression. They believe that until there is a better understanding of what the drug does in the body, caution should be exercised when prescribing it to children.
Cystic fibrosis (CF) is a lifelong genetic disease that causes the body to produce thick mucus that clogs the digestive system and causes lung infections. In the 1970s, few patients lived past their teens; today, about half make it to their 40s.
Patients, who are often hospitalised for the effects of the disease, say Kaftrio is “close to a cure” as it helps them lead normal lives. But since it was made available in 2020, stories of psychiatric problems have emerged.
Two years ago, The Mail on Sunday was first to sound the alarm after adults with cystic fibrosis reported a range of problems they said had been triggered by the pills, including severe depression, debilitating brain fog and memory problems.
It is not clear why the drug might cause mental health problems or who might be most affected (file image)
A woman in her 30s began experiencing extreme anger and depression, migraines, seizures and temporary paralysis. In two shocking cases reported by this newspaper in 2022, a woman attempted suicide and a nine-year-old boy with no history of mental health issues began self-harming after starting a similar medication.
At the time, health professionals and the Cystic Fibrosis Foundation suggested that these problems might be a result of the life-changing nature of the treatment, not the drug itself. But following our reporting, the patient advice leaflets included in Kaftrio packages were updated to include depression as a possible side effect.
Kaftrio, as well as other similar drugs such as Symkevi, Orkambi and Kalydeco, are known as CFTR modulators, as they correct the fault in a gene called CFTR that causes the most debilitating symptoms of cystic fibrosis. They are all manufactured by the American pharmaceutical company Vertex.
A company spokesman said last night: “We have conducted an in-depth analysis of all available data and based on this comprehensive assessment we found no causal relationship between Kaftrio and psychiatric events, nor did we find a causal association of Kaftrio with low mood, sleep, concentration and memory problems, or challenging behaviour in children and young people.”
Kaftrio, as well as similar drugs such as Symkevi, Orkambi and Kalydeco, are known as CFTR modulators because they correct the fault in a gene called CFTR that causes the most debilitating symptoms of cystic fibrosis.
We have reached out to the mother of the nine-year-old boy, who previously spoke to the MoS about the side effects her son suffered from taking Symkevi and Kalydeco.
She said the drugs had caused her “happy” son to cry constantly. She later discovered he had started scratching his face and arms with a razor.
Her doctor told her to stop taking the medication and she quickly returned to normal.
Last summer, the boy, now 11, started taking Kaftrio. His mother says: “The problems started almost as soon as he started taking the medication – it was like a change. He went from being a happy, cheerful, confident boy who loved football to being tearful and angry. And he started self-harming again, which is terrifying.”
The medication was again taken away and he quickly returned to normal.
‘I’m in a Facebook group for parents of children with cystic fibrosis. There are endless posts about behavioural problems. I can’t help but think that Kaftrio is the cause.’
David Ramsden of the CF Trust said that while the effects of Kaftrio have been positive for most, “we know this has not been the case for everyone”.