Company: United Therapeutics ($UTHR)
Based: Silver Spring, MD
R&D budget: $171M (€124M)
Change from 2009: +36.5%
Net revenue spent on R&D: 27.6%

United has charted much of its future R&D course in recent years on the market for treatments for pulmonary arterial hypertension--with mixed results. When the company's latest pivotal trial for its lead experimental PAH treatment, an oral formulation of treprostinil, failed in August, United President and COO Roger Jeffs said the company would journey toward an FDA approval filing anyway with data from an earlier Phase III study that was a success.

United enriched its stake in potential drugs for pulmonary hypertension--which causes high blood pressure in the blood vessels from the heart to the lungs--in June, when the company announced its exclusive license to Israel-based Pluristem's placental cell-based tech to develop treatments for the disease. The company also has a mid-stage program involving a formulation of beraprost for pulmonary hypertension.

This isn't to say that United hasn't kept moving in other areas of research. The company recently took on a potential $45 million NIH contract to develop an oral antiviral against dengue fever and influenza. The company is also in the clinic with tissue-scarring and cancer treatment programs.