New single-shot vaccine could offer controlled release of multiple doses over six months

• CEPI to fund new innovation that condenses multiple vaccine doses into one shot
• Vaccine encapsulated in microparticles, coated with nanoscopic layers of metal oxide, enables controlled release of doses
• Specialised vaccine could also be thermostable, increasing access to doses in hard-to-reach settings

OSLO/ BOULDER, CO, 24 APRIL 2025—Pioneering new research is set to investigate a promising vaccine technology designed to remove the need for cold-chain storage and condense multi-dose regimens into a single, controlled-release vaccination. 

The U.S.-based company, VitriVax, has developed their proprietary vaccine design, Atomic Layering Thermostable Antigen and Adjuvant (ALTA®), to replace multi-dose vaccines for protection against an infectious disease with a single-administration alternative. The company’s innovative approach in the pharma industry, known as ‘atomic layering deposition’, is used to control the release of the vaccine in the body over time. 

The Coalition for Epidemic Preparedness Innovations (CEPI) is providing up to $5 million in grant funding to VitriVax to develop further the ALTA® technology as it could offer a simplified way to protect populations during an outbreak and help control the spread of a threatening pathogen. 

The funding will be used to test ALTA® in preclinical trials using Rabies as a disease target*. If successful, scientists will prepare the vaccine candidate for Phase I trials, the clinical research stage used to assess the safety of a vaccine in a small group of people. Learnings from the research could be applicable to other emerging infectious diseases CEPI is focusing on, including a new or as-yet-identified ‘Disease X’, as well as other vaccine antigens and adjuvants.

“Receiving all the doses of protection you need in one go – with doses safely and slowly released over time - could be a gamechanger when it comes to effective outbreak response” explains Dr Kent Kester, Executive Director of Vaccine Research and Development at CEPI. 

“As well as saving on costs, a multi-dose vaccine regimen delivered in a single shot would help ensure that more people are fully protected from a virus over time, helping to reduce the chance of repeat outbreaks and save more lives. The vaccine could be especially advantageous for use by nomadic populations and refugees, as well as in conflict settings where they may be difficulties in making repeat visits to the clinic for follow-up doses.”

The ALTA® platform is designed to enable the delivery of multiple vaccine doses in a single injection through a proprietary spray-drying process. This method encapsulates the antigen/adjuvant within a glassy sugar matrix, protecting the active ingredients from heat and chemical degradation. The resulting spray-dried powders are then transferred to a specialized reactor, where they undergo a controlled coating process with the metal oxide, alum. By precisely adjusting the thickness of the alum coating around each vaccine particle, scientists can determine the timing of dose release in the body. Currently, ALTA® vaccines are designed to release subsequent doses up to six months following a single injection.

ALTA®-formulated vaccines could offer several potential advantages over traditional liquid vaccines. Specifically, they remain stable at high temperatures for prolonged periods without losing efficacy, eliminating the need for refrigeration. This stability could enable broader distribution of vaccine doses, particularly in low-resource regions and hard-to-reach areas. Additionally, ALTA® vaccines could be formulated to require lower amounts of antigen and adjuvant, reducing overall production costs, making them more cost-effective for low- and middle-income countries.

"CEPI funding will accelerate the advancement of our vaccine technology, particularly its application to the rabies immunization,” said Romulo Colindres, Chief Executive Officer of VitriVax. “We believe the ALTA® platform has the potential to simplify the delivery of the vaccination by providing complete multi-dose protection in a single shot, as well as eliminate the need for cold chain storage. This is especially important in remote or resource-constrained regions where rabies remains a serious threat."​

This is the latest vaccine project to be supported by CEPI’s call for vaccine innovations to tackle future epidemic and pandemic threats. 

VitriVax is already assessing the use of the ALTA® platform for multi-dose vaccine administration in a single shot against other diseases including Melioidosis, Glanders and Polio. 

CEPI and VitriVax are committed to enabling equitable access to the outputs of their partnership, in line with CEPI’s Equitable Access Policy. Should the project be successful, CEPI has the option to explore providing further funding to VitriVax to assess the technology against other infectious diseases which require a multi-dose vaccination or for use with other vaccine technologies. Project results, including related data, will be published open access for the benefit of the global scientific community.

ENDS

*Researchers at VitriVax will explore whether Serum Institute of India’s three-dose Rabies vaccine, RabiVax-S, could be adapted on the ALTA® platform, with the first prime dose and the follow-up booster doses delivered in the single-shot then released over a selected time. VitriVax will compare whether the adapted vaccine achieves similar levels of immunity to the current programme where the three doses are administered separately. It will also test whether the vaccine, which normally requires refrigeration, can be made thermostable.

About CEPI

CEPI was launched in 2017 as an innovative partnership between public, private, philanthropic and civil organisations. Its mission is to accelerate the development of vaccines and other biologic countermeasures against epidemic and pandemic threats so they can be accessible to all people in need. CEPI has supported the development of more than 60 vaccine candidates or platform technologies against multiple known high-risk pathogens or a future Disease X. Central to CEPI’s pandemic-beating plan is the ‘100 Days Mission’ to compress the time taken to develop safe, effective, globally accessible vaccines against new threats to just 100 days.

About VitriVax

VitriVax, headquartered in Boulder, Colorado, is a vaccine formulation technology company that engineers innovative solutions to maximize global accessibility and utility of human vaccines – vaccines that save lives and protect our world from preventable disease.