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Rats develop translatable pulmonary arterial hypertension (PAH) after exposure to the VEGF antagonist semaxanib (SU5416) concurrent with hypoxia. Sildenafil is used clinically for PAH and as a positive control in this preclinical model. A longitudinal analysis was constructed by pooling data from discrete rat PAH studies conducted over an 8-year period to evaluate the stability and reproducibility of the SU5416/Hypoxia rodent model as well as the response to sildenafil. Sprague-Dawley rats were administered SU5416 on Day 1 and subsequently maintained in a low oxygen environment for 28 days. Sildenafil was given as a positive control in either prevention or treatment mode. Pulmonary hemodynamics were obtained on the final day as appropriate by design; hearts were also assessed for right ventricular hypertrophy. Prevention studies (≥17) were terminated following 28 days of hypoxia while most treatment studies (≥17) had a protocol-defined period of normoxia following hypoxia. In prevention studies, the mean of both systolic pulmonary arterial pressure (sPAP) and the right ventricular hypertrophy Fulton’s Index (FI) remained consistent across studies over the 7-year period: sPAP: PAH vehicle control (PAH-VC) 70 ± 19 mmHg (n = 190), sildenafil 51 ± 15 mmHg (n = 165), p