PM meets French president in Paris, insisting Brexit impasse can be broken "with energy and creativity".
The drug combination has huge potential and would cost just "pennies a day", say the researchers.
Traffic is expected to peak on Friday as holidaymakers share the roads with commuter traffic.
The boy was taken to hospital where "nothing could be done to save him", West Midlands Police said.
Chesterholme's owner also runs Whorlton Hall, where filming appeared to show patients abused.