Medical food and dietary supplement developer Provexis reported a wider pre-tax loss, hurt by increased research and development expenses, while its plans to acquire a sports nutrition products manufacturer failed to inspire investors. For the year ended March 31, Provexis posted a loss before tax of £2.3m, or 17p a share, compared with a pre-tax loss of £1.7m, a year earlier. The company said the increase in R&D costs reflects the recruitment of additional staff and the continuation of the clinical trial for its Crohn's disease treatment.Separately, Provexis said it has entered into a conditional agreement to buy Science in Sport for approximately £8m. The deal is to be partially funded by a £2.5m conditional placing at 1.5p per share, which is expected to be completed by June 24.Shares of the company lost slightly more than 20% of their value in the morning trading session. AR