A SLEEPING pill that triggered a period of consciousness in a comatose patient after being administered to calm a bout of restlessness is to be taken into full clinical trials, The Times has learnt.

A British company is to begin trials of zolpidem on up to 30 patients later this year, such is the promise shown by the drug at temporarily bringing people out of vegetative states.

Louis, a young South African, had been in a coma for more than three years when he was given the pill as a routine sedative in the care home where he was being treated.

To the amazement of his mother and doctor, within an hour he was awake and speaking again. The effects of zolpidem lasted for about four hours, before Louis, who was 31 at the time, slipped back into the permanent vegetative state (PVS). It was the first time that he had shown any awareness of people, and been able to respond to them, since a car crash three years earlier.

The pill has since been given to two other PVS patients, who have shown similar responses. It also triggered the temporary recovery of speech and co-ordination in several stroke victims and sufferers of movement disorders.

ReGen Therapeutics, a London biotech company, is sponsoring phase II clinical trials, which will involve 20-30 patients with brain injuries. The trials will be held in South Africa, pending approval by the drugs regulator, with an interim report scheduled for early next year. They aim to provide clinical proof of zolpidem’s efficacy in smaller doses, to lessen any sedative side effects.

The seemingly miraculous case of Louis, who was left in a coma after being hit by a lorry while cycling, has echoes of patients treated with L-Dopa, a brain stimulant. The L-Dopa cases, made famous by the Hollywood film Awakenings, involved some survivors of a rare disease called encephalitis lethargica, or sleeping sickness. A few were temporarily awoken with L-Dopa, but they developed an intolerance to the drug over time.

However, studies of zolpidem, known by the brand name Stilnoct in Britain, suggest that its efficacy does not weaken with continued use. Louis, the first PVS patient to show the effects of the drug, was first given it in late 1999. Six and half years on, he continues to take 10mg of the drug daily, with the same effect.

Wally Nel, the GP who first gave Louis zolpidem, said the impact was totally unexpected. Louis began to show awareness of his surroundings within 20 minutes, and after an hour managed to start conversing. When asked his favourite rugby player, he was able to answer.

“He was restless, so I gave him the zolpidem as sedation,” Dr Nel said. “The effect was simply amazing.”

Dr Nel’s research colleague, Ralf Clauss, who has also seen the effects of zolpidem on Louis and two other PVS patients, described the transformation as “gobsmacking”. He said: “About 15 minutes after [Louis] is given the tablet he begins getting a reddish flush and a bit of a cough. As time goes by he starts to wake up.”

Two other patients, G and N, were also studied by the doctors, who reported their findings this week in the journal NeuroRehabilitation.

Dr Clauss said that, although the patient still had severe brain injuries that would always impair aspects of normal behaviour, the “dormancy” of their comatose state was lifted.

Some neurologists have urged caution, suggesting that the patients may not have had PVS. Mike Barnes, professor of neurological rehabilitation at the Hunters Moor Centre, Newcastle upon Tyne, said a study carried out ten years ago had shown that up to 45 per cent of patients thought to have PVS had other conditions from which they could wake up.

A LIVING DEATH

• A person in a permanent vegetative state (PVS) may appear to be awake with their eyes open but shows no awareness of his or her surroundings
• They are not able to respond to people or to sounds or events
• They may sleep and eat as normal, show signs of movement and be able to breathe unaided

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