Drugs used to treat HIV are to be trialled in people with incurable multiple brain tumours.
Scientists think ritonavir and lopinavir could shrink tumours in patients with neurofibromatosis 2 (NF2), a genetic condition where tumours grow along nerves.
The tumours are normally non-cancerous but can cause symptoms such as balance problems, hearing loss and ringing in the ears.
If they are in the brain and spinal cord or along the nerves of the arms and legs, sufferers can get persistent headaches and limb weakness.
About one in 25,000 to 40,000 people have NF2 but there are no treatments apart from surgery.
A trial involving 12 people will for the first time explore lab studies that show the HIV drugs can shrink and slow down NF2 tumours.
Other studies have suggested they could also help other types of brain tumour.
Professor Oliver Hanemann, from the Brain Tumour Research Centre of Excellence at the University of Plymouth, is leading the trial.
“This could be the first step towards a systemic treatment for tumours related to NF2, both for patients who have inherited NF2 and developed multiple tumours, as well as patients who have a one-off NF2 mutation and have developed a tumour as a result,” he said.
“If results are positive and the research develops into a larger clinical trial, it would be the most significant change for patients with this condition, for whom there is no effective treatment.”
The trial will see patients take the two medicines for 30 days and having a biopsy and blood test both before and after.
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Jayne Sweeney, 57, who’s had chemotherapy and five operations to remove tumours in her brain, ankle and ear, said the trial was “incredibly exciting”.
“If we can find an effective drug for people newly diagnosed, that would be fantastic,” she said.
“For me, the loss of hearing is the worst thing about having NF2 because it’s very isolating and frustrating.”
“Finding better and kinder ways to treat the disease is so important,” she added.
In half of NF2 cases, the faulty gene is passed from mother to child, but in others cases the gene appears to develop spontaneously.
Most patients eventually get serious hearing loss that becomes worse over time.