The distraught girlfriend of one of two men fighting for their lives in a London hospital after being poisoned in a drug trial today said she had barely recognised him because his head was so swollen.

Myfanwy Marshall, 35, said that her boyfriend looked "like the Elephant Man" after being given a dose of the drug, TGN 1412.

Her boyfriend is a 28-year-old landlord who had taken part in drug trials before without adverse side effects, but is now in the intensive care unit at Northwick Park hospital, Harrow, north-west London.

Five other men were also admitted to the intensive care unit at Northwick Park from an independent medical research unit on the hospital campus after taking part in the trial. The six, all paid volunteers, had reacted badly to the drug, which is formulated to treat chronic inflammatory conditions and leukaemia.

The hospital said this evening that two of the young men were in a critical condition today while four others, still in intensive care, were in a serious state but showing signs of improvement.

Ganesh Suntharalingham, clinical director of intensive care, said: “We are continuing to treat the inflammatory disorder triggered by the drug and the effects. We have given some treatment aimed at the immune system and the patients are continuing to receive a whole range of treatments that the Critical Care Service offers.”

Ms Marshall said that her boyfriend felt ill 80 or 90 minutes after being given an oral or injected dose of the drug. She told BBC News 24: "He is like a shell of who he is and this machine is pumping out his lungs. His chest is puffed out. He is already a big kind of guy but his face is out here, like Elephant Man, it’s completely puffed.

"His friends can’t even face seeing him. I have to stay there looking behind the wires and the puffiness because he is in there. I’m trying to talk in his ear, they say sometimes he can hear.

"I’m trying to say ‘get your cells to regenerate, tell your body to regenerate itself’ because that’s all the hope they are giving me. They haven’t got a cure. This is not leukaemia. This is a drug they have never tested on humans before so they don’t know what they are dealing with. It’s completely messed up their vital organs."

The men fell ill on Monday evening, after which the Medicines and Healthcare products Regulatory Agency (MHRA), the UK medicines watchdog, immediately suspended the trial and sent inspectors to the research unit to carry out an investigation.

It is working with the North West London Strategic Health Authority, the Department of Health and the Metropolitan Police, to find out what happened.

Professor Kent Woods, the organisation’s chief executive officer, said: "Our immediate priority has been to ensure that no further patients are harmed. We will now undertake an exhaustive investigation to determine the cause and ensure all appropriate actions are taken."

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