From here, symptoms can progress rapidly with accumulation of fluid within the lungs followed by respiratory collapse and failure.

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The cells' shape is affected because a protein within it - haemoglobin which carries oxygen from the lungs to the rest of the body - is different to normal.

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Within a few weeks, she had regained the strength in her legs and lungs.

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One melanoma patient who had tumors clogging her lungs was able to go off oxygen within weeks of starting on the drug.

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But because the review process involves research and public comment and because there's not enough organ donations for children, the nation's transplant system won't likely be able to save the life of Sarah Murnaghan, who could die within weeks without a transplant of lungs.

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