Less than three years ago, North-East woman Siobhan Kielty was a prisoner to multiple sclerosis (MS).

Now, thanks to her fighting spirit and a revolutionary drug, she has thrown away her wheelchair and proudly struts the catwalk.

She spoke yesterday about the medical breakthrough drug - beta interferon - that has transformed her life.

"Looking back now it's hard to believe, but I was unable to move at home without a zimmer frame, and would need a wheelchair to go out. I suffered repeated blindness and paralysis to various limbs,'' said Siobhan, 28.

"MS is such a cruel disease. You can be perfectly normal one day then wake up disabled, unable to function. The psychological effect of wondering when it will strike next can be very traumatic.''

The first signs for Siobhan came in 1994, when she suffered numbness in her hands and legs - but it was another two years before doctors identified her condition as MS.

"I remember trying to put on some make-up, but my hand wouldn't do what my brain was telling it. I ended up with mascara all over my face," she said.

Siobhan, who works for the Benefits Agency, in Middlesborough, soon began suffering dozens of attacks which left her blind, or paralysed, for weeks on end - and always in fear that the condition would become permanent.

In the two years since she started taking beta interferon, Siobhan has had just two minor relapses. She has moved into a flat in Redcar, east Cleveland, and launched a modelling career.

"My doctor mentioned beta interferon," she said. "He said it was a new drug and did I want to be a guinea pig? I said I'd give it a go.

"The results have been amazing. I live life to the full now. I had always wanted to try modelling and the drug gave me the confidence and strength to do that.

"I can go out at weekends to discos and parties.''

Despite the drug's success, the National Institute for Clinical Excellence has provisionally recommended it should not be prescribed to any new NHS patients on the grounds of "clinical and cost-effectiveness".

A final decision is expected next month