Darleukin (L19-IL2) is an immunostimulatory compound consisting of the human vascular targeting antibody L19 and the human cytokine, interleukin 2 (IL-2). The rationale for the development of this product relies on the fact that recombinant IL-2 is an approved biopharmaceutical (“Proleukin TM”; Novartis) and that the fusion protein has demonstrated a striking superiority compared to non-targeted IL-2 in models of cancer. Cytokines such as IL-2 directly stimulate immune effector cells and stromal cells at the tumor site and enhance tumor cell killing by lymphocytes and NK cells.
Darleukin has already been tested in clinical studies in melanoma and pancreatic cancer. More recently, combination of Darleukin with other immunocytokines or with chemotherapeutic drugs has shown potent synergistic activity in pre-clinical studies, and therefore the current clinical trial strategy is based on this concept.
Based on the encouraging results from a Phase II trial for the intralesional administration of Darleukin in combination with Philogen’s product Fibromun (L19-TNF) in melanoma skin lesions, a registrational Phase III clinical trial has started in Q4 2015.
Darleukin, in combination with dacarbazine, has been compared to dacarbazine monotherapy in patients with Stage IV melanoma. Clinical studies are continuing, with the aim to further improve the schedule and dose.
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