<p>Described is a complex comprising a fibronectin and a physiologically active substance having a functional group capable of combining with a protein. If necessary, a protein cross-linking agent is used to link the physiologically active substance to the fibronectin.
<??>Physiologically active substances, such as antibiotics, can preferentially or selectively be transported by means of such complexes to a morbid region, for example an injured tissue or an area showing neoplastic cell proliferation.
<??>The complex fibronectin is administered in order to cure morbid regions.</p>
