Safety and Efficacy of Lurbinectedin as a Second-Line Treatment for SCLC
A thought leader in lung cancer, Hossein Borghaei, DO, reviews safety and efficacy data from the phase 2 basket trial of lurbinectedin in selected advanced solid tumors.
Hossein Borghaei, DO: The clinical evidence for the use of lurbinectedin comes from a single-arm study that included around 100 patients. Patients in the study had ECOG PS [performance status] of around 0 to 2. They must have had at least 1 prior chemotherapy. Immunotherapy use was allowed, but patients with active CNS [central nervous system] metastases were excluded from the study. A dose of 3.2 mg/m2 was selected as the standard dose for this particular agent, a single drug given by IV [intravenous] once every 3 weeks. And the study was a single-arm trial.
In patients who are chemotherapy-sensitive, using that 90-day marker as our reference, patients who had chemotherapy-sensitive disease ended up having a 45% response rate vs about 22% for those who were defined as chemotherapy resistant, which is better than many of the drugs—especially for the chemotherapy-sensitive patient population—we’ve had access to. The antitumor activity and duration of response and all that were good, and this was a single-arm study, so it’s hard to say how the drug compares with another arm. But we know from historical data that topotecan would not give us this level of response.
The median duration of response in the chemotherapy-sensitive patient population was roughly around 6 months, and in a chemotherapy-resistant patient population it was close to 5 months. The median overall survival was almost 12 months in the group that was defined as having chemotherapy-sensitive disease vs about 5 months in chemotherapy resistant. The drug compares favorably with other drugs that we have in this category.
In my clinical practice, I’ve used lurbinectedin on a handful of patients with metastatic small cell following chemoimmunotherapy with evidence of disease progression. My experience has been rather positive. It’s a drug that does have some myelosuppression associated with it, so following these patients closely is absolutely needed. I know that it goes without saying, but we’re giving drugs with potential adverse effects, so obviously the monitoring has to be rigorous. But the myelosuppression part is something that has caught my attention in terms of monitoring the red blood cell count and possibly discussing the need for the use of a growth factor, like G-CSF [granulocyte colony-stimulating factor], to maintain the red blood cell to help with that.
Like many other drugs that we use in this category, other adverse effects such as fatigue can be seen. But overall, it’s a simple drug. It’s once every 3 weeks, so it makes it a little more convenient to use than topotecan. We’ll have to wait for subsequent studies to see if the results of a single-arm study can be confirmed.
Transcript edited for clarity.
