• The HD-MAP platform technology offers user-friendly vaccines, allowing possible self-administration. Its room temperature stability revolutionizes distribution, reducing costs and expanding vaccination access, particularly in lower- to middle-income countries.

SK bioscience, an innovative vaccine and biotech company committed to promoting human health from prevention to cure, announced today that the company has entered into a collaboration agreement with Vaxxas, an Australian biotechnology company developing a unique vaccine patch platform technology, to develop a second-generation typhoid conjugate vaccine with support from Wellcome.

SK bioscience's SKYTyphoid™ vaccine will be reformulated so that it can be 'printed' onto the thousands of tiny microprojections covering the Vaxxas patch to be delivered directly to the abundant immune cells just under the skin surface. This reformulation aims to enhance access and broaden markets where traditional intramuscular delivery using needle and syringe has been employed.

Under the agreement, SK bioscience will supply the antigen utilized by its typhoid conjugate vaccine, SKYTyhpoid™ that was jointly developed by SK bioscience and the International Vaccine Institute (IVI).

Vaxxas will be responsible for reformulating the SKYTyphoid antigen so that it can be applied to its proprietary HD-MAPs, and then conduct preclinical studies, which if successful, will be followed by a Phase I human clinical trial. The project is expected to be completed within two years from initiation to reporting the data from the Phase I clinical trial.

The project is being supported by approximately AU$5.4 million (GB£2.84 million / US$3.67 million) in grant funding received from Wellcome.

Wellcome is a global charitable foundation supporting discovery research into life, health and wellbeing, and action to take on mental health, infectious disease and climate and health. Their infectious disease programme supports projects to help increase understanding of the sources of disease and drivers of escalation, as well as accessible and affordable solutions to control the impact of infections.

SK bioscience collaborated with Wellcome and the IVI on the development of a trivalent invasive non-typhoidal Salmonellosis vaccine candidate in 2019. In October 2022, SK bioscience also signed a memorandum of understanding (MoU) with Hilleman Laboratories, a research institute established by MSD and Wellcome, for a strategic partnership to co-develop new vaccine candidates and technology platforms.

As Vaxxas' HD-MAPs deliver the vaccine directly to abundant immune cells in the skin, they hold the potential to be more immunogenic than traditional needle and syringe administration, and they offer the prospect of reduced dosing. Vaxxas' user-friendly applicator facilitates simplified self-administration accommodating individuals with varying skill levels.

Vaxxas' innovation to reformulate vaccines for application on HD-MAPs and subsequent drying can prevent drug deterioration and improve vaccine stability. This could allow storing and distributing vaccines at room temperatures, which is vital for making vaccines more accessible in lower- and middle- income countries with limited cold-chain distribution infrastructure.

SKYTyphoid is a polysaccharide-protein conjugate (Vi-DT) vaccine, formulated by conjugating the polysaccharide of Typhi, which serves as an antigen, to diphtheria toxin protein, which serves as a carrier.

SK bioscience received funding to develop SKYTyphoid from the Bill & Melinda Gates Foundation in the early stages of the development. Based on its immunogenicity and safety, SKYTyphoid obtained an approval for exportation from the Ministry of Food and Drug Safety (MFDS) in May 2022, and is expected to obtain WHO Prequalification this year.

Compared to a current polysaccharide vaccine, SKYTyphoid provides acceptable immunogenicity and long-term preventive effects with a single-dose administration. Furthermore, the vaccine can be administered to infants 6 months to 2 years of age.

Typhoid fever is a life-threatening infection caused by the bacterium Salmonella Typhi. It is usually spread through contaminated food or water. The disease continues to be a public health problem in many developing countries in Africa, Middle East, and Southeast where there is a continuing lack of clean water supply and lack of adequate sewage facilities.

According to the World Health Organization, an estimated 9 million cases of typhoid fever occur globally each year.Symptoms include prolonged high fever, fatigue, headache, nausea, abdominal pain, and constipation or diarrhea with mortality rates up to 30%.^[1]

Pierre Balard, Senior Research Manager at Wellcome said, "To help protect more people at risk from deadly diseases like typhoid fever, new vaccine innovations are needed to improve access and ensure equitable coverage. Vaxxas' high-density microarray patch (HD-MAP) is an important step in this direction. With the potential to overcome some of the most enduring barriers to vaccine access in lower income countries, this product could be a vital addition to our global toolkit."

David L. Hoey, President and CEO of Vaxxas said "We are excited to be initiating this important work with Wellcome and SK bioscience to leverage our HD-MAP vaccine platform to potentially enhance typhoid vaccination. We believe our HD-MAP can play a critical role in extending the global reach of typhoid conjugate vaccines, and make a significant difference to the lives of many."

Jaeyong Ahn, CEO of SK bioscience said, "Typhoid fever is a dangerous disease that frequently occurs in low- and middle- income countries, but the utilization of typhoid vaccines has been limited due to the requirement for vaccines that remain stable under varying temperatures and those that can be administered without medical supervision. This collaboration with Vaxxas provides an opportunity to overcome those challenges. We will continue to develop various formulations and products that can contribute to human health based on cross-border cooperation with international organizations and institutions, such as Wellcome and Vaxxas."