Brother and sister team Amit and Meeta Patel own and run Ruislip-based Auden Mckenzie (Pharma Division). The firm specialises in injectable products such as Synastone (methadone), which is licensed for the treatment of heroin addiction and as an alternative to morphine for pain relief. It's a lucrative market - profits hit £28.9m on £52.4m of sales in 2012-13.
The fast-growing west London operation was founded in 2001, holds more than 120 pharmaceutical product licences and sells its wares in 30 countries. It was the Patels' father who identified a niche market for generic versions of such highly specialised medicines and, armed with £150,000 seed capital, the company was launched, staffed only by the three family members. 'I did not need to go to business school, because I learned everything from watching my father,' Amit Patel has said. The business now employs over 79 people and supplies hospitals, pharmacies and wholesalers.
Ages: 39 and 40
Latest turnover: £52m
Five-year rise in turnover: 373%
No. of employees: 79
Five-year rise in employment: 229%