The raging covid-19 pandemic has brought attention to the onerous cold storage requirements of vaccines. The Moderna covid-19 vaccine requires cold storage at minus 20 degrees Celsius and the Pfizer vaccines requires ultra-cold conditions at minus 70 degrees Celsius. To maintain a cold chain and handle these vaccines is a daunting challenge. Not only is it technically demanding and extremely costly, but it may also preclude large groups of people from having access to the vaccine with an impact on live and death.
These requirements on cold storage are, however, not unique to covid-19 vaccines. Injectable vaccines are often heat sensitive pharmaceuticals with very short shelf life in room temperature.
There are studies showing that the lack of cold storage leads to large wastage of drug. Maintaining an unbroken cold chain also adds a significant cost to a vaccine. Estimates made by WHO suggest that the cold chain accounts for 14% of the cost of vaccination and up to about 5USD per dose. This is a very significant cost in developing countries. In a vaccination programme in rural Vietnam in 2005, it was estimated that the wastage of doses was as high as 33% for some pharmaceuticals. An even larger risk is that people are vaccinated with an inactive vaccine and not receiving the expected protection from disease.
In addition to the burden of cold storage, injections also present a safety risk to both patients and health professionals. There is a great risk of injuries and infections when used needles are not properly disposed of. WHO estimates that contaminated syringes cause 21 million of hepatitis B infections, 2 million of hepatitis C infections and over 200 000 HIV infections that place a significant burden on the healthcare system. This is mainly caused by re-using syringes scavenged at waste disposals and landfills.
The drawbacks mentioned above provide a strong driver to consider better alternatives to injected vaccines, like inhaled vaccine. The lung is a suitable route of administration for dry powder vaccines.
There are several scientific publications reporting successful use of dry powder inhaled vaccines for diseases like the measles, influenza vaccine, Ebola, Tuberculosis, Pertussis (Whooping Cough), Pneumonia, Hepatitis B and Diphtheria.
There are not only clinical advantages but also pharmaceutical advantages like:
• No need for sterility and sterile water
• No preparation before use
• Easy to use – no medically trained staff needed
• Safe - no risk of needle injuries
• No need for cold storage and reduced wastage
• Simple and safe handling and disposal after use - no management of high-risk waste
• No proliferation of used needles
• Low cost - Simple to manufacture
The commonly used dry powder inhalers on the market are not suitable for the delivery of an inhaled dry powder vaccine as they are designed for multi-dose use and are not cost efficient for single dose administration. Iconovo has developed ICOone, which is a novel disposable unit dose inhaler comprising only one injection molded part. This offers the lowest possible manufacturing cost. Even though the device is simple to manufacture, it provides superb humidity protection for the dry powder and simple administration as the user only has to pull a tab and inhale.
It is proven to work with various types of formulations like spray dried, freeze dried or conventional carrier-based formulations used in asthma inhalers. A dose up to 50 mg can be delivered with a respirable fraction of 60-70%.
ICOone is not only suitable for vaccine delivery but also for the treatment of viral infections like e.g. covid-19 and for rescue treatment of hypoglycemia with glucagon or adrenalin for allergic reactions.
ICOone is currently being used in a clinical trial with inhaled dry powder oxytocin to prevent postpartum hemorrhage (PPH). This is a cooperation with Monash University’s Institute of Pharmaceutical Sciences (MIPS) in Melbourne, Australia. MIPS recently entered into an R&D agreement with Janssen Pharmaceutica, part of Johnson & Johnson, to further advance the clinical development of inhaled oxytocin for the prevention of PPH in developing countries.
ICOone is also used in a program to develop dry powder tuberculosis vaccine together with McMaster University in Canada.