ImmunoGen Inc. (NASDAQ: IMGN) has released data from its late-stage ovarian cancer study at the European Society for Medical Oncology (ESMO) 2019 Congress in Barcelona, Spain. Specifically, this data comes from the Phase 3 Forward study evaluating mirvetuximab soravtansine compared to chemotherapy in women.
The primary endpoint of this study was progression-free survival, which was assessed using the Hochberg procedure in the entire study population and in the subset of patients with high folate receptor alpha-positive expression.
In the entire study population, the confirmed overall response rate was higher for mirvetuximab than for chemotherapy (22% versus 12%), without a significant difference in the primary endpoint of progression-free survival or overall survival.
Mirvetuximab was well tolerated, with fewer patients experiencing grade 3 or greater treatment-emergent adverse events (46% versus 61%), fewer dose reductions (20% vs 31%), and fewer discontinuations due to drug-related treatment-emergent adverse events (5% versus 8%) compared with chemotherapy.
Dr. Kathleen Moore, associate director of Clinical Research at the Stephenson Cancer Center at the University of Oklahoma, commented:
While it is disappointing that FORWARD I did not meet the primary endpoint of progression-free survival, mirvetuximab demonstrated consistent and meaningful efficacy signals in patients with high levels of FRα expression and was well tolerated with a differentiated safety profile in both the ITT and FRα high populations. Despite recently reported advances in frontline treatment with the addition of PARPi maintenance therapy, the majority of patients will unfortunately develop platinum-resistant disease with limited therapeutic options characterized by low response rates, short progression-free survival, and significant toxicities. The encouraging data from FORWARD I suggest the potential for a significant improvement over single-agent chemotherapy in the FRα high population and I look forward to the continued development of mirvetuximab for these patients in the upcoming Phase 3 study.
Shares of ImmunoGen were last seen down about 8% at $2.51, in a 52-week range of $1.76 to $9.84. The consensus price target is $4.67.