After Eli Lilly and Co. (NYSE: LLY) announced results from its midstage clinical trial for the treatment of lung cancer, its shares dipped on Monday. Specifically, these results come from the Phase 1/2 Libretto-001 trial of selpercatinib, LOXO-292, for the treatment of RET fusion-positive non-small cell lung cancer (NSCLC).
The selpercatinib treatment resulted in a 68% objective response rate (ORR). This population was heavily pretreated and ORR was similar regardless of prior therapy. Up to 50% of RET fusion-positive NSCLCs can metastasize to the brain, and in the subset of patients with brain metastases in the registrational dataset, selpercatinib treatment demonstrated a CNS (central nervous system) ORR of 91%.
As of the data cut-off date of June 17, 2019, median duration of response was 20.3 months and median progression-free survival was 18.4 months. Since the majority of patients remain in response or progression-free as of the data cut-off date, these medians will continue to mature over time.
In a safety analysis of all 531 patients enrolled to Libretto-001, selpercatinib was well-tolerated, with only 9 patients (1.7%) discontinuing therapy due to treatment-related toxicity. The most commonly observed adverse events were dry mouth, diarrhea, hypertension, increased liver enzymes, fatigue, constipation, and headache.
These results were presented in the Presidential Symposium Session at the 2019 World Conference on Lung Cancer in Barcelona, Spain, hosted by the International Association for the Study of Lung Cancer.
Selpercatinib had previously received breakthrough therapy designation from the U.S. Food and Drug Administration (FDA).
Alexander Drilon, M.D., lead investigator, Memorial Sloan Kettering Cancer Center in New York City, commented:
In this large cohort, selpercatinib’s response rate, durability, robust CNS activity, and safety show promise. Furthermore, this continues to confirm that RET fusions are clinically targetable alterations, placing them in the company of activating EGFR/ALK/ROS1 alterations. We are encouraged by these data as there is currently an unmet need to provide genomically-tailored therapy to patients with RET fusion-positive NSCLCs.
Shares of Eli Lilly traded down about 3% on Monday to $110.80, in a 52-week range of $104.17 to $132.13. The consensus price target is $123.83.