The company, which launched in 2002 as a spin-out from Imperial College London, has developed technologies that can keep drugs active in the body for longer.

Longbow Capital, which specialises in healthcare and technology investments, put in some £1.3 million, the lion’s share of the funding. Technology commercialisation company Imperial Innovations Group invested £750,000, while the Regional Venture Capital Fund for London made up the balance of £250,000.

This is the second round of funding for PolyTherics, which was set up with the backing of £850,000 from the Wellcome Trust and the Bloomsbury BioSeed Fund.

PolyTherics CEO Keith Powell says: ‘Having products in pre-clinical trials before first-round fundraising and a demonstrated core technology makes the company an exciting prospect. We now have three partnerships with product-focused pharma companies underway and are already generating revenue from this.’

Imperial Innovations Group was founded in 1986 and floated on AIM in July 2006, raising £26 million. The company aims to incubate and invest in technology businesses with valuable intellectual property, and is also based at Imperial College London.