Neither of the referenced studies note when the treatment started; one states "plus standard NHS treatment", which implies presentation at a hostpital -- usually days after onset of symptoms.
Virtually all of the studies that do indicate treatment initiation within 1-3 days of onset of symptoms do strongly indicate effectiveness.
It seems ... odd to avoid disclosing average start of treatment from onset of symptoms, don't you think? Especially when this appears to be the primary determinant of successful treatment in numerous (>100) studies?