A student who was due to take part in a trial of the drug which has left six men seriously ill has spoken of his concern for those involved.
By Hannah Goff
BBC News health reporter
Student David has done a number of drugs trials
Student David O'Donnell, 19, was expecting to take part in a higher dose trial of the drug, TGN1412, in April but it was cancelled when the six men were taken ill.
One of his friends, who is said to be in a serious condition in hospital, was actually on the trial.
"I am very worried about him indeed but I had a message from my friends to say they have managed to get in contact with him."
He said that as he was "partly responsible" for letting his friend know about the financial benefits of the trial, he felt a certain amount of "irrational guilt".
The first year economics student at university in Birmingham said that as someone who has done a number of different drugs trials, he was "very shocked" when he heard how the subjects had reacted to the drug.
But Mr O'Donnell said his main reaction was one not of relief for himself but of fear for those left ill.
He told the BBC News website: "Understandably, it was a strange experience, but primarily I was more concerned with the well-being of those involved.
"There's a certain sense of relief. But it's a situation where the bad luck involved definitely outweighs the good luck.
"I have another friend who was going to do that trial as well, and he is equally relieved."
The 19-year-old said many students took part in the trials because of the large sums of money involved.
He added: "Being a student, it is very difficult to find flexible employment. Clinical trials allow us to earn large sums of money in a small amount of time."
The fee for the trial in question, he said, was the equivalent of a student loan and would make a real difference to a student's life.
They might even enable them to pay off their tuition fees.
However, the events at Northwick Park Hospital have not shaken Mr O'Donnell's faith in clinical trials and he still plans to take part in one in the near future.
"When I've been doing these trials there have been a number of safety measures in place.
"I've always found them to be professional and responsible for everything they have done.
"I sincerely believe this is an anomaly and not a regular occurrence. It is a freak, unlucky accident."
He added that without them the pharmaceutical industry and the medical profession would not be able to find new cures for devastating diseases.