Aluminum-based adjuvants are a type of substance that is added to some vaccines to enhance the body's immune response to the vaccine. They are called adjuvants because they "adjourn" or boost the effectiveness of the vaccine. Aluminum adjuvants have been used in vaccines for decades and are one of the most widely studied and used adjuvants in the world.
There is evidence to suggest that aluminum adjuvants are effective at enhancing the body's immune response to vaccines. When a vaccine is given, the body's immune system responds by producing antibodies to fight off the disease that the vaccine is designed to protect against. The presence of an adjuvant in the vaccine can help to boost the production of these antibodies, resulting in a stronger and longer-lasting immune response.
Current Issues With Aluminum-Adjuvants
Aluminum-based adjuvants are the most common type of adjuvant used in vaccines. These adjuvants are made up of insoluble irregular-shaped micrometer-sized particles. Vaccines that contain aluminum adjuvants are typically formulated as aqueous suspensions. However, aluminum adjuvants tend to be heavier than water and sediment, which causes quality issues for these vaccines both before and after they are released for use.
The sedimentation of suspended particles during the fill-finish step of manufacturing can cause uneven filling of containers, such as vials. For some vaccines, filling aluminum adjuvants over the regulatory limit (0.85 mg Al(III) per dose in the US, 1.25 mg Al(III) per dose in Europe) can lead to subpar efficacy or a product recall.
Aluminum-adjuvanted vaccines may sediment to the bottom of the vial during transportation and storage, requiring vigorous shaking before use. If the vaccine is not fully re-suspended, it can lead to defects at the drug product level that are not detectable through prefilling testing of the drug substance, posing challenges for quality control. These defects may cause vial-to-vial variability and may go undetected unless every vial in a batch is inspected.
For example, in April 2010, the World Health Organization recommended the recall and destruction of all lots of SHAN5 vaccines that contained particles that were not fully re-suspended by shaking. If the uneven filling is significant, it can result in miss-dosing.
One challenge with current commercial aluminum adjuvants is that they are only available in liquid form, which poses logistical issues. There is a need to develop lyophilized thermostable formulations and excipients that enable stability during freezing temperature fluctuations, which could make it easier to deliver these adjuvants to resource-poor areas. Nano adjuvants have been proven to be more effective than traditional adjuvants in various academic studies. However, aluminum-based nano adjuvants are not yet available for commercial use. This is due to the difficulty in controlling the key physicochemical properties and scaling up commercial production using the current available manufacturing process.
The Adjucon Solution
Adoxima and Adjucon, using its trademarked DNC Technology, has solved many aluminum nano adjuvant critical technical bottlenecks. By demonstrating the critical attributes at a pilot scale according to Indian, Australian, US, and EU regulatory standards will make it a viable option for integration into existing vaccine formulations by vaccine manufacturers.
Adjucon Product Benefits
High Surface To Volume Ratio
Large surface areas generate a higher capacity of interaction sites. This has important implications for antigen delivery, improved bio-availability, and controlled release.
Stable Colloidal Suspension
Our product demonstrates remarkably stable colloidal suspension. Stable colloidal suspension generates better adsorption and homogeneity of multi-component vaccine formulation
High Antigen Suspension
Our high antigen adsorption property is the manifestation of small crystallite size and high surface-to-volume ratios. Studies indicate that small crystallite size induced a stronger antigen-specific antibody response.
High-Purity
Trace metals are below detection limits. Studies indicate that high amounts of elemental impurities can affect vaccine stability
Adjucon is in the process of moving into a Pilot scale facility to start supplying nano-adjuvants and exploring long-term partnerships within the industry.
For more information, including material data sheets, please contact info@adoxima.com.