WHEN Darren Scrine hit his 30th birthday he felt tired and listless all the time. At first he put it down his demanding job and busy family life.

"I turned 30 and I thought my energy levels were going. I just thought I was getting older," he recalls.

Fed up with his lack of energy, he went to see his GP. That began a sequence of events which led to the devastating news that he had chronic myeloid leukaemia, or CML.

Affecting around 4,000 people in Britain at any time, this form of leukaemia is usually fatal unless a bone marrow transplant can be carried out.

A form of cancer, it means the white blood cells reproduce uncontrollably, crowding out the oxygen-carrying, energy-giving red blood cells and ultimately killing the patient.

Sufferers who are unable to get a good tissue match have an average of five years to live following diagnosis.

Trying to stay calm despite being given a virtual sentence of death, Darren used the skills he had learned as a website technican manager and surfed the Internet for information about leukaemia in the hope that a cure might be on the horizon.

"You feel as if you have a timebomb ticking inside you, you don't know how long you have got," Darren says.

After hours of surfing he struck gold.

"I came across a news story on an American website which said a new drug had been tested on 30 leukaemia patients and all of them had gone into remission."

Crucially, it gave the name of the new drug - ST1571 - which allowed Darren to step up his search.

"I heard that they were going to start trials in the UK in a couple of months, at Hammersmith and at Newcastle," he recalls.

Being based in Peterborough, Darren tried Hammersmith first but they were only allowing two patients a month get on the trial - and it had to be less than six months since diagnosis. Four months had already passed since Darren was told he had CML.

Fearful of the future, he threw his energies into setting up a European website for CML sufferers.

He was amazed when he was contacted by a blood specialist from Newcastle Royal Victoria Infirmary, a connection which led to him being given a place on a drug trial - and a chance of life.

"Dr O'Brien said he had one place left. I said I want it, I will be there tomorrow," he says.

There was no guarantee that Darren would get the new drug. The trial is randomised and half the patients get ST1571 and the other half get interferon, the standard current treatment which has a good track record in prolonging life but not in curing the condition.

Darren was lucky and was put on the new drug and started taking the pills on June 30.

Three months later he had a bone marrow biopsy which showed that the drug had cleared 98 per cent of the disease.

"It is amazing really. You just take four tablets a day and suddenly your leukaemia is gone. It makes you think that in the future people will be given a prescription for all kinds of cancer," says Darren, who is deeply grateful to Dr O'Brien and the rest of the RVI team.

"They don't know whether it stays away for ever, but I will carry on taking the drug. Within three months it killed 98 per cent and I am more than likely completely cleared now," says Darren.

Consultant haematologist, Dr Stephen O'Brien is so impressed by the new drug he can hardly contain his excitement.

"Even when you are very cautious it is still a very impressive drug," says Dr O'Brien, who was at the American Society of Haematology meeting in San Francisco this week when the results of the clinical trials were announced to the world's top leukaemia experts.

He describes the results - which show that one third of patients who took ST1571 for six months had no evidence of any remaining leukaemia - as "very exciting, a watershed in the leukaemia treatment."

Compared to the rigours and uncertain outcome of a bone marrow transplant, the prospect of popping a pill four or six times a day to treat leukaemia is mind-boggling for doctors and patients

Unlike other anti-cancer drugs, it works by selectively switching off signal proteins related to a faulty chromosome in the leukaemic cell, killing the malfunctioning cells and leaving healthy cells intact.

Side effects with ST1571 are relatively minor. Many patients have no side effects at all and the drug is easy to take.

In contrast to conventional chemotherapy, there is no infertility and no hair loss.

The other alternative, interferon, prolongs survival but has many side-effects, the commonest of which are flu-like symptoms.

Dr O'Brien wants to know the long-term effects of ST1571 before getting really enthusiastic but so far things are looking very good.

"As yet, we don't know how long responses to ST1571 will last or whether these patients are cured. We need results from five years of clinical trials before we get enough information to be confident that this drug improves survival for leukaemia patients," he says.

However, Dr O'Brien, a senior lecturer with Newcastle University's department of haematology, says the drug "clearly represents a major breakthrough in the treatment of chronic myeloid leukaemia."

It also paves the way for the development of new types of anti-cancer drugs that could improve survival while offering minimal side effects and good quality of life.

News of the drug has given fresh hope to North-East leukaemia sufferer Jolene Kimberley, who underwent a painful bone marrow transplant to eradicate her disease.

Although she has lymphoblastic aneamia, a different, more curable form of the blood disease, she knew several CML patients who died because there was nothing doctors could do for them.

"This sounds really fantastic, it is a real breakthrough," says Jolene, 22, of Middlesbrough, who has put her wedding plans to Darren Armstrong back on the agenda after her successful transplant.

"I am really pleased for the patients who will get this treatment but it is just a shame it was too late for my friends," she says.