HotHouse closes £2.9m pre-seed to grow vaccine adjuvants using AI plant engineering
This article covers HotHouse Therapeutic, a biotech startup, which has emerged from stealth with a £2.9m pre-seed round to commercialise an AI-driven plant bioengineering platform for producing vaccine adjuvants and other pharmaceutical compounds. The development aims to provide a lower-cost, scalable alternative to extractive supply chains for high-value natural products such as QS-21, supporting vaccine developers and efforts to improve supply-chain resilience and equitable access to key vaccine ingredients.
HotHouse Therapeutic, a biotech startup based in Norwich, has emerged from stealth with a £2.9m pre-seed round to commercialise an AI-driven, plant bioengineering platform aimed at producing vaccine adjuvants and other pharmaceutical compounds. The company says its approach could reduce dependence on fragile, resource-intensive supply chains for molecules such as QS-21 and offer a lower-cost, more scalable route to important vaccine ingredients.
Why it matters
QS-21, a widely used vaccine adjuvant, is currently extracted from the bark of a slow-growing Chilean tree. That single-source supply is resource-intensive, fragile and unable to scale to meet global demand, a problem that disproportionately affects low- and middle-income countries. HotHouse positions its technology as an alternative: reprogrammed plants that can be grown more predictably and locally to provide consistent, affordable access to high-value natural products and novel derivatives.
The announcement is relevant to conversations about resilient pharmaceutical supply chains, greener manufacturing and equitable vaccine access. HotHouse’s model also intersects with broader policy priorities in the UK and Europe around onshoring critical biomedical manufacturing and supporting biotech innovation through grants such as Innovate UK.
Inside the product
HotHouse combines two named components. BotanAI is its design engine for pathway prediction and molecule generation. BotanBIO is its production system that uses a transient plant expression method to reprogramme plant leaves into production hosts. The company says this lets it explore chemical space that standard laboratories cannot and rapidly generate both natural and new-to-nature single-entity compounds.
Key technical and commercial claims from the release:
- A transient plant expression system that converts plant leaves into production platforms.
- Capability to access more than 20 million novel molecules by pairing AI-driven pathway prediction with plant enzymatic diversity.
- A focus on saponin-based adjuvants, including sustainable access to QS-21 and QS-7, plus a library of novel derivatives.
- A carbon-positive, vertical farm-ready production approach intended to reduce environmental impact compared with extractive or resource-heavy chemistry.
- Plans for traditional drug discovery programmes to progress assets towards clinical development and early preclinical data comparing HotHouse candidates to QS-21 to support partnerships.
The platform traces its scientific origins to the work of Professor Anne Osbourn OBE, FRS, whose research demonstrated that complex molecules like QS-21 can be biosynthesised in plants. That pedigree underpins HotHouse’s stated aim to translate plant natural product pathways into manufacturable pharmaceutical chemistry.
Who are the investors?
HotHouse has closed a £2.9m pre-seed round that includes SynBioVen, Start Codon, UKI2S, Twin Path Ventures, Wren Capital, a syndicate of angel investors and funding from an Innovate UK grant. The company says the funds will accelerate platform development, generate preclinical data for adjuvant candidates and establish commercial routes such as exclusive supply agreements, adjuvant panels and bespoke discovery projects with pharma and vaccine developers.
Investors appear to be backing a combination of sustainable manufacturing, AI-enabled discovery and potential routes into global health markets, with the Innovate UK element signalling public support for R&D that targets supply chain resilience and broader access.
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Founder perspective
The company is led by David Sheppard, who was cited in the announcement as having spent the past year building a team across AI, natural product biology, purification science and chemistry.
In the announcement, David Sheppard, CEO at HotHouse Therapeutic, said:
We grow greener medicines using a platform that makes the impossible accessible. The drug discovery field desperately needs new chemical space and the vaccine field needs new adjuvants, with supply chains that work for everyone. By combining AI with plant engineering, we can reach molecules others cannot, and scale them in a way that supports global health, not just high-income markets.
In the announcement, David Sheppard, CEO at HotHouse Therapeutic, said:
Our mission is simple. Unlock powerful chemistry, make it sustainable, and get it into the hands of the partners who can deliver vaccines and therapeutics to patients across the globe.
Sheppard’s public comments emphasise supply-chain resilience and global access rather than near-term commercialisation milestones. The company will now need to translate platform claims into reproducible preclinical data and partner agreements to reach commercial impact.
The bigger picture
HotHouse sits at the intersection of several trends: AI-guided molecule discovery, plant-based biomanufacturing and a policy moment focused on strengthening national and regional pharmaceutical supply chains. Replacing extractive sources for high-value natural products could ease pressures on ecosystems and supply reliability, but it also raises technical and regulatory challenges before such products can reach the clinic.
The deal and Innovate UK support reflect ongoing interest from biotech investors in sustainable production approaches that have both commercial and public-health rationale. If HotHouse can validate its platform with comparative preclinical data and secure partnerships with vaccine developers and global health organisations, it will add to a growing UK capability in bio-based manufacturing and AI-driven drug discovery.
This development will be watched by policymakers and funders across the UK and Europe as they look to diversify and decarbonise pharmaceutical supply chains while maintaining access to critical vaccine components.
They've invested in HotHouse Therapeutic
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