David Cameron has pledged to do what he can to help make a breakthrough treatment available on the NHS after meeting a nine-year-old boy it could benefit.
Archie Hill suffers from Duchenne muscular dystrophy which will soon leave him needing a wheelchair.
But a drug called Translarna could enable sufferers to walk for longer after it was approved in August.
It is currently available to boys in France, Spain, Germany, Italy and Denmark but UK families say it is taking too long to be approved on the NHS.
The drug will only work while Archie can walk so if his condition deteriorates he could miss out on it completely.
This prompted him to hand in a 22, 785 signature petition to Downing Street in a bid to speed things up.
Archie, who was diagnosed with the condition when he was just three, said: "I was happy to meet the Prime Minister and to give him my letter. He was very nice and asked me about my football team."
His mother Louisa said: "Archie knows that there is a medicine out there that could help him keep playing football for longer. That means everything to our little boy."
During Prime Minister's Questions, Mr Cameron told Parliament: " I was looking at this issue last night and there was a child, who was about the same age as my son, pictured with his local football team, just as my son was.
"It made me think how vital it is to get these drugs through as quickly as we can.
"I know that there has been a debate on whether these drugs should be licensed quickly and on all the issues and problems. I will meet those parents, look at their petition and see what can be done."
Muscular Dystrophy causes irreversible muscle damage and problems with heart and lung muscles mean most sufferers do not currently live beyond 30.