UK scientists create dry-powder vaccine that stays effective without refrigeration

Researchers in the UK have turned a tetanus-diphtheria shot into a stable dry powder that can be stored at room temperature for a year and still trigger immune protection.

UK scientists have successfully tested a fridge-free version of a tetanus-diphtheria vaccine by converting it into a dry powder using the sugar trehalose, keeping it stable at room temperature for a year before reconstitution. In a first-in-human trial of 60 volunteers, the powder elicited immune responses that matched those of the standard refrigerated formulation and was well tolerated. The project, conducted by the National Institute for Health and Care Research and biotech firm Stablepharma, seeks to address the roughly half of global vaccine doses lost each year due to cold-chain breakdowns.

A follow-up trial with 160 participants will serve as the final research phase, as the original vaccine is already licensed. Researchers note the method may also protect other temperature-sensitive medicines, and it aligns with WHO goals for vaccines that survive 30 °C and 75 % humidity. Stakeholders from WHO, UNICEF and the UK-Southeast Asia Vaccine Manufacturing Research Hub praised the potential impact on immunisation programmes in low-resource settings.