Mirvetuximab soravtansine active in previously treated ovarian cancer
Mirvetuximab soravtansine induced confirmed objective response in about one-third of women with folate receptor alpha-high platinum-resistant ovarian cancer who previously received bevacizumab, according to the agent’s manufacturer.
Mirvetuximab soravtansine (IMGN853, ImmunoGen) is a first-in-class antibody-drug conjugate that comprises a folate receptor alpha-binding antibody, cleavable linker, and the maytansinoid payload DM4, a tubulin-targeting agent.
The single-arm SORAYA study assessed mirvetuximab soravtansine monotherapy for 106 women with folate receptor alpha-high, platinum-resistant ovarian cancer.
Study participants had received a median three prior lines of therapy (range, 1-4). All patients had received prior bevacizumab (Avastin, Genentech) and 48% received a poly(ADP-ribose) polymerase (PARP) inhibitor.
Median follow-up was 8.1 months.
The study met its primary endpoint, with company-issued topline results showing a confirmed objective response rate of 32.4% (95% CI, 23.6-42.2) per investigator assessment and 31.6% (95% CI, 22.4-41.9) by blinded independent central review. Researchers reported responses regardless of prior PARP inhibitor therapy or number of prior lines of therapy.
Median duration of response, a key secondary endpoint, was 5.9 months (95% CI, 5.6-7.7).
Treatment-related adverse events led to dose reductions for 19% of study participants, dose delays for 32% and treatment discontinuation for 7%.
The most common treatment-related adverse events included blurred vision (all grade, 41%; grade 3 or higher, 6% ), keratopathy (all grade, 35%; grade 3 or higher, 9%) and nausea (all grade, 29%; grade 3 or higher, 0%).
"Despite advances in the platinum-sensitive setting, most patients with ovarian cancer eventually develop platinum-resistant disease, for which there are limited treatment options, especially for those patients who have previously received bevacizumab," Robert Coleman, MD, chief scientific officer of US Oncology Research and co-principal investigator of the SORAYA study, said in an ImmunoGen-issued press release. “Data from SORAYA have the potential to redefine the standard of care for patients with [folate receptor alpha-high] platinum-resistant ovarian cancer, as this trial has demonstrated that mirvetuximab delivers clinically meaningful benefit in this setting, with significant and durable responses and a favorable tolerability profile.”