SAN FRANCISCO, November 7, 2016 /PRNewswire/ -- The Pulmonary Arterial Hypertension (PAH) market is expected to reach USD 8.7 billion by 2025, according to the new report by Grand View Research, Inc. Incidents of PAH, increasing geriatric population, and government support to develop orphan drugs are key driving factors. Cumulatively, the cases of PAH are in the range of 100,000 to 200,000 per year. However, in the past few years, the prevalence of this disorder is rising due to risk factors like sedentary lifestyle, HIV, smoking, alcohol/tobacco consumption, and other idiopathic conditions. (Logo: http://photos.prnewswire.com/prnh/20150105/723757 ) The presence of a large population over 60 years globally, which has lower immunity levels and is prone to PAH and associated diseases, which is a high impact-rendering driver for the growth of the market over the forecast period. Supportive government initiatives for the development of drugs for rare diseases or orphan drugs are anticipated to facilitate the market growth over the forecast period. For instance, the Orphan Drug Act (ODA) 1983, and Rare Disease Act 2002 in the U.S. offer incentives such as tax credits for the development of orphan drugs. Patent expiry of key PAH molecules is projected to have a deep impact on market dynamics. In coming two to four years the exclusivity of key brands such as Tracleer, Remodulin, Adcirca, Ventavis, Tyvaso, and Letairis will be lost. This will foster the entry of generic product at prices much lower than branded drugs.