Vaccines typically contain inactivated viruses or bacteria antigens which stimulate the inherent immune system, triggering an immune response. As a result, corresponding antibodies are produced which provide immunity from the actual pathogen for which the vaccine is designed. In addition to inactivated viruses or bacteria antigens, vaccines also contain some excipients aimed at increasing their efficacy and safety. Some vaccine excipients, intermediates and process solutions used in downstream vaccine processing are removed from the final vaccine, whereas the rest are essential ingredients for the final formulation.


Vaccine manufacturing can be broadly classified into two parts: upstream and downstream manufacturing. Upstream process involves growing virus or bacteria under controlled conditions. When the required pathogens are obtained, downstream processing begins with harvesting and purifying antigens, followed by formulating the final vaccine product. Downstream process utilizes several intermediates, process solutions and vaccine excipients before the final product is tested for safety and efficacy. Downstream processing is complex and critical, as it directly affects the quality, efficacy and safety of the final vaccine product. All downstream processing intermediates, process solutions and vaccine excipients are required to be manufactured under full GMP compliance to pass stringent quality checks laid out by relevant regulatory bodies, to ensure safety and efficacy of the final products.


Downstream vaccine manufacturing processes require different GMP grade vaccine excipients for specific purposes as described below:

  • Inactivating agents: Inactivating agents are used to attenuate viruses and bacteria or to inactivate disease toxins. Inactivating agents are essential to reduce pathogenicity of viruses or bacteria to safe levels. Some of the vaccine excipients widely used as inactivating agents include GMP grade Polysorbate 80 and GMP grade Formaldehyde. After successful inactivation of viruses or bacteria, these agents are removed before further processing of vaccine formulations.
  • Purification agents: Following deactivation of viruses or bacteria, antigens are required to be separated from the co-precipitated material. This purification step is crucial in obtaining high yields of antigens for further processing. Some of vaccine excipients used as purification agents include GMP grades of CTAB and Benzalkonium Chloride.
  • Buffers and process solutions: pH changes during multi-stage vaccine manufacturing processes can degrade inactivated antigens and thus reduce their efficacy. To maintain pH of media within the required window, buffers are employed to resist change in pH. Some of the widely used buffers are GMP grades of Sodium Phosphate, Potassium Phosphate and Sodium Citrate buffers.
  •  Stabilizers: To withstand environmental elements during storage, transport and handling, vaccines are added with vaccine excipients that work as stabilizing agents, such as GMP grade 2-Phenoxyethanol, Sucrose and Urea.
  • Tonicity adjusters: For rapid dissolution and distribution after administration, vaccines are required to be isotonic to bodily fluids. A number of salts, including GMP grades of Sodium Chloride and Calcium Chloride, are extensively used in vaccines to achieve required tonicity of vaccines matching bodily fluids, for optimum dosage delivery.


  • Preservatives: Small quantities of preservatives are also added to the final vaccine to prevent bacterial and fungal contamination during storage and usage, particularly for multi-dose vials. Some of the approved preservatives include GMP grades of Thimerosal, Formaldehyde, Phenol, Benzalkonium Chloride and 2-Phenoxyethanol.


A&C has been servicing the vaccine industry for several years. We supply a wide range of GMP grade vaccine excipients, intermediates and process solutions to vaccine manufacturers around the world. Our vaccine excipients are used in a number of novel vaccines developed and marketed by some of the world’s leading vaccine manufacturers.

We provide GMP custom development of niche and novel excipients ,  GMP custom manufacturin, GMP packaging and down packing of liquid and powder raw materials. At A&C, we offer tailor-made GMP solutions for excipients and raw materials, from early-stage formulation development to late-stage commercial scale supply.


Below is a list of the main vaccine excipients, raw materials, buffers and process solutions that A&C offers for your vaccine manufacturing needs.