The present invention relates to improved pharmaceutical formulations, uses and methods for the oral delivery of peptide or protein drugs with advantageously high bioavailability, safety and cost-effectiveness. In particular, the invention provides a peptide or protein drug having a molecular weight of equal to or less than about 50 kDa for use as a medicament, wherein said peptide or protein drug is to be administered orally in combination with a pharmaceutically acceptable copper salt/complex and/or a pharmaceutically acceptable zinc salt/complex, and with a pharmaceutically acceptable reducing agent. The invention also provides a pharmaceutical composition comprising: a peptide or protein drug having a molecular weight of equal to or less than about 50 kDa a pharmaceutically acceptable copper salt/complex and/or a pharmaceutically acceptable zinc salt/complex and a pharmaceutically acceptable reducing agent.
