Allergy Therapeutics plc (LON:AGY) saw revenues grow 12% to £48.5mln for the six months ended June.
But a £16.2mln research and development spending drive meant losses widened to £13mln, resulting in losses per share of 2.29p.
Allergy Therapeutics said the global allergy treatment market had seen some “turmoil” affecting the competitive market environment in Europe and the US, but the group said it would likely see mid to long-term benefits in terms of its US market share.
The UK’s referendum vote had a short-term financial benefit for the group in terms of the weak pound against the euro, but the group said the long-term impact will depend on the final agreement between the UK and the rest of the EU.
The group had a self-confessed “mixed year” with a successful Phase II dose-ranging study for Pollinex Quattro Birch in Germany opening the way for a Phase III trial for the product in Europe, which is expected to start in early 2017.
The one-year follow-up study on Acarovac Plus concluded with patients reporting statistically significant improvements in satisfaction scores for effectiveness and convenience.
However, its Phase II Pollinex Quattro study in the US did not give conclusive evidence of an optimal dose regime.
“The allergy immunotherapy sector continues to undergo significant change and within this context our established and innovative product base continues to gain traction,” said chief executive Manuel Llobet.
The current allergy immunotherapy market is estimated to be US$2.1bn (£1.62bn) with the potential to reach US$3bn and is expected to grow at about 11% a year until 2020.
“We look forward to the future with confidence in continued growth given our strong and expanded European presence, future product development pipeline and geographic expansion opportunities,” added Llobet.
Shares fell 3% to 17.78p.