The present invention discloses methods for inducing regression of a tumor
in a subject by administering a pharmaceutical composition comprising a
lentogenic strain of Newcastle disease virus (NDV). A preferred viral
strain of NDV for inducing regression of a tumor in a subject is a clonal
strain of NDV, the NDV HUJ. The methods of the present invention are
particularly useful for inducing regression of tumors in patients
unresponsive to conventional anti-cancer therapies.