Formulation

A pharmaceutical formulation comprising: a first active ingredient (e.g. a peptide or peptide derivative) which is unstable; a second active ingredient, a bulk diluent 0.1 -10 wt.% dibasic calcium phosphate anhydrous and, optionally, one or more further adjuvants and/or excipients. Preferably, the first active ingredient is an angiotensin-converting enzyme inhibitor, most preferably lisinopril. The second active ingredient may be a calcium channel blocker such as amlodipine. The bulk diluent may be a polyol, e.g. mannitol. The first and second active components may be present in a ratio of 1:3 to 3:1. The pharmaceutical composition may be a compressed tablet. The composition may be used to treat hypertension. Also claimed is a process for the preparation of a pharmaceutical formulation comprising: combining the first active ingredient, bulk diluent, and, optionally, one or more further adjuvants and/or excipients and homogenising; adding a binder solution; granulating the mixture; drying at atmospheric pressure; adding the second active ingredient to form a bulk formulation. A lubricant may be added to the composition.