MIRASOL: A Randomized, Open-label, Phase 3 Study of Mirvetuximab Soravtansine vs. Investigator's Choice of Chemotherapy in Platinum-Resistant, Advanced High-Grade Epithelial Ovarian, Primary Peritoneal, or Fallopian Tube Cancers With High Folate Receptor-Alpha Expression

Platinum resistant FRalpha+ high grade serous ovarian cancer

453, median 2 prior therapies (1-3); 62% w/ prior bevacizumab; 56% w/ prior PARP inhibitor

Recurrence

Open-Label, Randomized

ORR, DCR, DoR, PFS, OS, evaluated per RECIST

FRalpha high: IHC: ≥ 75% tumor cells at ≥ 2+ intensity

Mir (n=227) vs TPC (Pac, PLD or Top, n=226):

ORR: 42 (12CR, 84PR) vs 16% (36PR), p<0.0001
DCR: 80 vs 56%
PFS: 5.62 vs 3.98 months, HR: 0.65 (0.52-0.81, p<0.0001)
OS: 16.46 vs 12.75 months, HR: 0.67 (0.50-0.89, p=0.0046)

Exploratory analysis, prior bevacizumab:
w/o prior bev: Mir vs TPC: PFS: 7.0 vs 5.6 months, HR: 0.66 (0.46-0.94, p=0.021); OS: 20.2 vs 14.4 months, HR: 0.51 (0.31-0.86, p=0.0099)
w/ prior bev: Mir vs TPC: PFS: 4.4 vs 3.0 months, HR: 0.64 (0.49-0.84, p=0.0011); OS: 15.4 vs 10.9 months, HR: 0.74 (0.54-1.04, p=0.0789) 

Serious AE: overall (24 vs 33%)
Grade 3-4 AE: overall (42 vs 54%), hematologic toxicities (<1 vs 19%), ocular toxicities (14 vs 0%)

Mirvetuximab soravtansine is the first treatment to demonstrate a PFS and OS benefit in Pt-R OC compared to single agent chemotherapy

Moore KN et al. Mirvetuximab Soravtansine in FRα-Positive, Platinum-Resistant Ovarian Cancer. N Eng J Med (2023) 389(23):2162-2174
https://pubmed.ncbi.nlm.nih.gov/38055253/