A BIOTECHNOLOGY company which is developing an inhaled alternative to Viagra has announced plans to float on the London stock market.

Vectura, in Chippenham, Wiltshire, is hoping to raise between £20m and £25m to give the company a market value of up to £85m.

The proceeds will be used to develop Vectura's range of inhaled drugs, including treatments for erectile dysfunction and lung disease.

Vectura's inhaled alternative to Viagra, VR004, is delivered into the bloodstream in about eight minutes - faster than pills, which can take an hour to act.

The market for erectile dysfunction treatments is estimated at £1.4bn worldwide.

Vectura employs 80 people at its Wiltshire base and a further 20 at a site in Cambridge, where it makes the inhalers used to administer the drugs. Shares will be priced at between 70p and 84p, and the offering is expected to take place in the first half of next month.