Correct grammar...?

Hey , I’m GeI have this tect to send to the school paper, but I think that the termas marked in red (my point of view) are not correct.

Could anyone give a look and give me an opion.



Thanks.

People are becoming increasingly aware of a medical condition known as narcolepsy, which causes sufferers to fall asleep anywhere at any time of the day. It is not just for own safety but is at risk. A man, who worked as a builder, fell asleep at the top of a ladder and could easily have fallen and killed both him and anyone passing by.

For years, no one/nobody had any idea what caused narcolepsy, and nearly that sufferers were given drugs which had serious side effects. Recently, however, researchers at Stanford University and the University of Texas have come to the/a conclusion that the problem due to an insufficient quantity of a chemical called orexin in the brain. ..........?..... this discovery has led to is the development of a new drug which appears to have no side effects at all.

Neither group of researchers has been slow to realise the potential of creating a drug. Not only would it help narcoleptics, but it could be used to help certain groups of workers, of surgeons and soldiers, to stay awake. The very latest trials, carried by on a group of young volunteers, have even shown that, with addition, the drug can improve many other aspects of mental functioning, including memory.