United Kingdom-based AstraZeneca's oncology immunotherapy Imfinzi (durvalumab) has received orphan drug designation from the US Food and Drug Administration (FDA) for the treatment of small cell lung cancer (SCLC), it was reported yesterday.

Last month, a phase three trial called CASPIAN met its primary endpoint with Imfinzi by delivering a statistically-significant and clinically-meaningful improvement in overall survival for patients suffering from extensive-stage SCLC.

The CASPIAN trial assessed Imfinzi in combination with standard-of-care etoposide and platinum-based chemotherapy against chemotherapy alone. The drug is also being assessed in limited-stage SCLC after concurrent chemoradiation therapy in a phase three trial, called ADRIATIC. Imfinzi is a human monoclonal antibody, which has been designed to target the PD-1/PD-L1 pathway.