- A. Menarini Farmaceutica Internazionale SRL
- AbbVie Ltd
- Accord Healthcare Limited
- Accord-UK Ltd
- Actelion Pharmaceuticals UK Ltd
- ADVANZ Pharma
- Aguettant Ltd
- AJ Vaccines A/S
- Akcea Therapeutics UK Ltd
- Alan Pharmaceuticals
- Alcon Eye Care UK Limited
- Alexion Pharma UK Ltd
- Alimera Sciences Limited
- ALK-Abello Ltd
- Allen & Hanburys Ltd
- Allergan Ltd
- Allergy Therapeutics
- Alliance Pharmaceuticals
- Almirall Limited
- Amgen Ltd
- Amneal Pharma Europe Limited
- Amryt Pharmaceuticals DAC
- AOP Orphan Pharmaceuticals AG
- Aristo Pharma Limited
- Aspen
- Aspire Pharma Ltd
- Astellas Pharma Ltd
- AstraZeneca UK Limited
- Atlantic Pharma Ltd
- Atnahs Pharma UK Ltd
- Auden Mckenzie (Pharma Division) Ltd (a subsidiary of Actavis PLC)
- Aurobindo Pharma - Milpharm Ltd.
