Specialist healthcare company BTG (LSE: BTG) has released a positive update for the six months to 30 September that shows the company is making progress.

On a constant currency basis, BTG delivered double-digit revenue growth in the period. This is in line with its expectations and its outlook for the full year remains unchanged. This is positive news for the company and shows that its strategy is performing well.

The acquisition of Galil Medical has improved and diversified BTG’s interventional oncology portfolio. This should improve its risk/reward profile over the medium term. Furthermore, BTG’s Varithena revenue increased and reflected the gradual increase in customers as well as rising reorder rates during the six month period.

BTG’s Speciality pharmaceuticals division also delivered good performance across its portfolio. In the Licensing division, it experienced good performances from Zytiga and Lemtrada, although year-on-year growth was held back by the one-off uplift of £8.5m in the prior period for Zytiga.

Although performance on a constant currency basis was impressive, when currency changes are factored in it was even more so. That’s because BTG benefitted from a weaker pound due to Brexit. Since the 23 June referendum, the pound has weakened severely against a basket of currencies. This is good news for BTG since a significant portion of its business is conducted outside of the UK and yet it reports in sterling.

Due to that weaker pound, it has increased its guidance for the full year. On a reported basis its revenue is now anticipated to be ahead of its previously announced guidance range of £510m-£540m. This should also have a positive impact on BTG’s profit outlook and its forecast for a 3% rise in earnings this year could improve.

Low value, high potential?

Looking ahead to next year, BTG is forecast to increase its bottom line by 37%. This puts it on a price-to-earnings growth (PEG) ratio of just 0.6, which indicates that it offers significant capital gain potential. However, it’s not the only healthcare company with upbeat growth prospects. Shire (LSE: SHP) is also on the cusp of improved financial performance and yet trades on a very low valuation.

For example, Shire is forecast to increase its bottom line by 87% this year and by a further 19% next year. This puts it on a PEG ratio of just 0.7, which indicates that it offers growth at a very reasonable price. However, Shire is undergoing a major change as it combines with Baxalta. While this should create a stronger and more profitable business in the long run, there are concerns among some investors that the two companies may not fit as well as is anticipated.

Due to its more appealing valuation and lack of risk regarding a major integration, BTG offers a more compelling investment than Shire right now. However, both stocks have significant upside potential.

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Peter Stephens has no position in any shares mentioned. The Motley Fool UK has recommended BTG. We Fools don't all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors.