Telemetric monitoring of vital parameters of patients with chronic diseases is recognized to improve their medical condition and hence their quality of life. It also improves treatment adjustments, reaction time in acute cases and helps to reduce duration and costs of hospitalization. As a result of this, there are plenty of products and solutions for personal health monitoring available today that acquire physiological data in real-time. In order for such systems to be widely acceptable and utilized by the medical community and the patients, they must be developed satisfying the security requirements imposed by real-time data communication and protection of sensitive physiological data and measurements, data integrity and confidentiality, and protection of the monitored patient's privacy. The work presented in this paper intends to fill the security gap, which makes these devices and the data acquired by them, vulnerable to any kind of attacks. By utilizing MPEG-21 standard's primitives, we show that protection of transmitted medical information and enhancement of patient's privacy is accomplished, since there is selective and controlled access to medical data that sent toward the hospital's servers.