drug lack of efficacy reports against Drug quality issue or defect

drug lack of efficacy reports against Drug quality issue or defect , need study or review around the globe about (regulatory authority of drug Ex. US FDA, MHRA, TGA, EMA, health Canada, WHO , ICH, NZ ….etc) how they deal with drug lack of efficacy report and Quality defect of drug, how it differentiate? how they chech that is lack of efficacy or decide it is quality defect? practice of Pharmacovigilance and post marketing surveillance references must be depends on those regulatory or agency website and also any guidelines from them or any other country