How do you treat patients with small cell lung cancer that is primarily refractory to platinum/etoposide (i.e. disease that continues to progress despite first-line chemotherapy?)

Unfortunately I have rarely seen second-line therapy provide meaningful benefit in patients with previously treated small cell lung cancer and have little enthusiasm for treating these patients outside of a clinical trial. Recently reported data for therapies such as nivolumab+Ipilimumab and rovalpi...