Parkinson’s disease (PD) severity is evaluated by neurologist experts by means of several tests. One of them is the Movement Disorder Society–Unified Parkinson’s Disease Rating Scale (MDS–UPDRS). The main hypothesis is that changes in the speech of PD patients reflect changes in their neurological state. In this study we use the Gaussian Mixture Model Universal Background Model approach to track the disease progression per speaker. Speech recordings from 62 PD patients were captured from 2012 to 2015 in three recording sessions. The validation of the models is performed with recordings of 7 patients (3 male and 4female). All of the patients were diagnosed by a neurologist expert according to the MDS–UPDRS–III score. The models were trained using speech recordings from male and female patients separately. According to the results, it is possible to track the disease progression with a Pearson’s correlation of up to 0.88 for males and 0.53 for females with respect to the MDS–UPDRS–III labels.