Two GCE grants explore new ways to deliver and manage vaccine supplies

The first of the two Grand Challenges Explorations (GCE) grants totaling US$100,000 each recently awarded to PATH by the Bill & Melinda Gates Foundation will help to advance the development of a novel protective liner for vaccine carriers. Currently in the early stages of product development, the low-cost liner designed by PATH is filled with a nontoxic engineered phase change material (PCM) that acts as a buffer, preventing the vaccine from freezing while maximizing the potential cold life and outreach duration of each carrier. Vaccines are often temporarily stored or transported in insulated vaccine carriers for periods of eight or more hours in ambient temperatures that can reach 40°C. The carriers are built to hold ice packs that help to keep the vaccines at cool temperatures. Although World Health Organization (WHO) guidelines state that cool packs (i.e., packs kept in the refrigerator instead of the freezer) should be used or that frozen ice packs should be allowed to thaw slightly before use, it remains a common practice in many countries for frozen ice packs to be placed directly in the carriers, raising the risk of exposure of a vaccine to extreme cold. Freezing temperatures can irreversibly damage many vaccines, especially those that contain aluminum salt adjuvants, which are common in many traditional vaccines as well as several of the newer, more expensive vaccines being introduced. If exposure to freezing temperatures is suspected, the vaccines must be discarded, resulting in vaccine wastage. If the vaccines are frozen, but not discarded, vaccines with reduced potency may be delivered to patients, leading to inadequate protection from disease. PATH’s protective PCM liner may soon eliminate the risks associated with frozen ice packs, helping to ensure the delivery of fully potent vaccines. PATH has retrofitted several WHO-prequalified vaccine carriers with the PCM liner, and a prototype is now being evaluated in Vietnam. Further assessments will be advanced under the GCE grant. The second GCE grant awarded to PATH will support feasibility studies of bar code technology to improve vaccine inventory management and supply forecasting when introducing new vaccines in low-income countries. Bar code technology and web-based data repositories hold promise for improving the availability and accessibility of real-time data on vaccine inventory, helping to prevent stockouts. A stronger data system could also ensure a country’s vaccine supplies are sent where they are needed most, helping to reduce wastage and inventory holding costs. In addition, the information could help match vaccine supply and demand at the global level, ensuring vaccines are allocated effectively. For more on these PATH projects, please see the original press release: www.path.org/news/an120509-grand-challenges.php For more information on the Gates Grand Challenges Explorations Grants for designing new approaches to optimizing immunization systems, please visit: www.path.org/news/an120509-grand-challenges.php