For the ITT population, Kaplan-Meier estimates showed no significant difference (HR, 0.98; 95% Cl, 0.73-1.31; P=0.897) in progression-free survival (PFS) between groups Median PFS was 4.10 and 4.40 months for MIRV and IC chemotherapy, respectively. In the prespecified high FR subgroup, PFS was longer in patients in the MIRV group compared with IC chemotherapy (median, 4.80 months versus 3.30 months; HR, 0.69, 95% CI, 0.48 to 1.00; P = 0.049). Based on the Hochberg procedure used in the statistical analysis plan for the study, this P value did not meet statistical significanceBoth in the ITT group and high FR subgroup, OS were not significantly different.

Mirvetuximab soravtansine vs IC chemotherapy in the ITT group: ORR=22.00% vs 12.00%, P=0.015; cancer antigen-125 (CA-125) responses=51.00% vs 27.00%, P<0001; median PFS2 duration (time from randomization to second disease progression or death)=10.00 vs 8.40 months, HR=0.64, 95% Cl, 0.49-0.84, P<0.001); PRO in the EORTC QLQ-OV28 Abdominal/GI Symptom Subscale=32.00% vs 14.00%, P=0.016; Mirvetuximab soravtansine vs IC chemotherapy in the high FR subset, ORR=24.00% vs 10.00%, P=0.014; cancer antigen-125 (CA-125) responses=53.00% vs 25.00%, P=0.001; median PFS2 duration=10.10 vs 8.40 months, HR=0.56, 95% Cl, 0.39-0.79, P<0.001); PRO in the EORTC QLQ-OV28 Abdominal/GI Symptom Subscale=27.00% vs 13.00%, P=0.143.

A phase 1b/2 study to evaluate the safety, tolerability and pharmacokinetics of mirvetuximab soravtansine (IMGN853) in combination with bevacizumab, carboplatin, pegylated liposomal doxorubicin, pembrolizumab, or bevacizumab + carboplatin, in adults with folate receptor alpha positive advanced epithelial ovarian cancer, primary peritoneal cancer, or fallopian tube cancer.

Dilutions of conjugates or unconjugated maytansinoid in the appropriate culture medium were added to wells of 96-well flat-bottomed plates containing 1 x10³ cells per well The plates were incubated at 37°C, 6% CO₂ for either 5 days (continuos exposure) or for 4 hours followed by 5-day incubation in conjugate-free medium (short exposure). Cell viability was determined by the WST-8 assay in accordance with the manufacturer's protocol, and IC50 were generated using a sigmoidal dose-response (variable slope) nonlinear regression curve fit.

Dilutions of conjugates or unconjugated maytansinoid in the appropriate culture medium were added to wells of 96-well flat-bottomed plates containing 1 x10³ cells per well The plates were incubated at 37°C, 6% CO₂ for either 5 days (continuos exposure) or for 4 hours followed by 5-day incubation in conjugate-free medium (short exposure). Cell viability was determined by the WST-8 assay in accordance with the manufacturer's protocol, and IC50 were generated using a sigmoidal dose-response (variable slope) nonlinear regression curve fit.

Dilutions of conjugates or unconjugated maytansinoid in the appropriate culture medium were added to wells of 96-well flat-bottomed plates containing 1 x10³ cells per well The plates were incubated at 37°C, 6% CO₂ for either 5 days (continuos exposure) or for 4 hours followed by 5-day incubation in conjugate-free medium (short exposure). Cell viability was determined by the WST-8 assay in accordance with the manufacturer's protocol, and IC50 were generated using a sigmoidal dose-response (variable slope) nonlinear regression curve fit.

Dilutions of conjugates or unconjugated maytansinoid in the appropriate culture medium were added to wells of 96-well flat-bottomed plates containing 1 x10³ cells per well The plates were incubated at 37°C, 6% CO₂ for either 5 days (continuos exposure) or for 4 hours followed by 5-day incubation in conjugate-free medium (short exposure). Cell viability was determined by the WST-8 assay in accordance with the manufacturer's protocol, and IC50 were generated using a sigmoidal dose-response (variable slope) nonlinear regression curve fit.

Dilutions of conjugates or unconjugated maytansinoid in the appropriate culture medium were added to wells of 96-well flat-bottomed plates containing 1 x10³ cells per well The plates were incubated at 37°C, 6% CO₂ for either 5 days (continuos exposure) or for 4 hours followed by 5-day incubation in conjugate-free medium (short exposure). Cell viability was determined by the WST-8 assay in accordance with the manufacturer's protocol, and IC50 were generated using a sigmoidal dose-response (variable slope) nonlinear regression curve fit.

Dilutions of conjugates or unconjugated maytansinoid in the appropriate culture medium were added to wells of 96-well flat-bottomed plates containing 1 x10³ cells per well The plates were incubated at 37°C, 6% CO₂ for either 5 days (continuos exposure) or for 4 hours followed by 5-day incubation in conjugate-free medium (short exposure). Cell viability was determined by the WST-8 assay in accordance with the manufacturer's protocol, and IC50 were generated using a sigmoidal dose-response (variable slope) nonlinear regression curve fit.

Five-week-old female CB-17 severe combined immunodeficient (SCID) mice were obtained and quarantined for 7 days prior to study initiation Mice were inoculated subcutaneously with KB cells (1 x10⁷ cells per mouse) resuspended in serum-free culture mediaMice with established KB xenografts were dosed with a single intravenous injection of 200 g of conjugated maytansinoid per kg, equivalent to 10² mg/kg antibody on day 6 after cell inoculationTumor dimensions were measured twice weekly and volume was calculated as (A B2) 05, where A represents the largest and B the perpendicular tumor diameter.

Dilutions of conjugates or unconjugated maytansinoid in the appropriate culture medium were added to wells of 96-well flat-bottomed plates containing 1 x10³ cells per well The plates were incubated at 37°C, 6% CO₂ for either 5 days (continuos exposure) or for 4 hours followed by 5-day incubation in conjugate-free medium (short exposure). Cell viability was determined by the WST-8 assay in accordance with the manufacturer's protocol, and IC50 were generated using a sigmoidal dose-response (variable slope) nonlinear regression curve fit.

Dilutions of conjugates or unconjugated maytansinoid in the appropriate culture medium were added to wells of 96-well flat-bottomed plates containing 1 x10³ cells per well The plates were incubated at 37°C, 6% CO₂ for either 5 days (continuos exposure) or for 4 hours followed by 5-day incubation in conjugate-free medium (short exposure). Cell viability was determined by the WST-8 assay in accordance with the manufacturer's protocol, and IC50 were generated using a sigmoidal dose-response (variable slope) nonlinear regression curve fit.

Dilutions of conjugates or unconjugated maytansinoid in the appropriate culture medium were added to wells of 96-well flat-bottomed plates containing 1 103 cells per well The plates were incubated at 37°C, 6% CO₂ for either 5 days (continuos exposure) or for 4 hours followed by 5-day incubation in conjugate-free medium (short exposure) Cell viability was determined by the WST-8 assay in accordance with the manufacturer's protocol, and IC50 were generated using a sigmoidal dose-response (variable slope) nonlinear regression curve fit.

Dilutions of conjugates or unconjugated maytansinoid in the appropriate culture medium were added to wells of 96-well flat-bottomed plates containing 1 x10³ cells per well The plates were incubated at 37°C, 6% CO₂ for either 5 days (continuos exposure) or for 4 hours followed by 5-day incubation in conjugate-free medium (short exposure). Cell viability was determined by the WST-8 assay in accordance with the manufacturer's protocol, and IC50 were generated using a sigmoidal dose-response (variable slope) nonlinear regression curve fit.

Dilutions of conjugates or unconjugated maytansinoid in the appropriate culture medium were added to wells of 96-well flat-bottomed plates containing 1 x10³ cells per well The plates were incubated at 37°C, 6% CO₂ for either 5 days (continuos exposure) or for 4 hours followed by 5-day incubation in conjugate-free medium (short exposure). Cell viability was determined by the WST-8 assay in accordance with the manufacturer's protocol, and IC50 were generated using a sigmoidal dose-response (variable slope) nonlinear regression curve fit.

Dilutions of conjugates or unconjugated maytansinoid in the appropriate culture medium were added to wells of 96-well flat-bottomed plates containing 1 x10³ cells per well The plates were incubated at 37°C, 6% CO₂ for either 5 days (continuos exposure) or for 4 hours followed by 5-day incubation in conjugate-free medium (short exposure). Cell viability was determined by the WST-8 assay in accordance with the manufacturer's protocol, and IC50 were generated using a sigmoidal dose-response (variable slope) nonlinear regression curve fit.

Dilutions of conjugates or unconjugated maytansinoid in the appropriate culture medium were added to wells of 96-well flat-bottomed plates containing 1 x10³ cells per well The plates were incubated at 37°C, 6% CO₂ for either 5 days (continuos exposure) or for 4 hours followed by 5-day incubation in conjugate-free medium (short exposure). Cell viability was determined by the WST-8 assay in accordance with the manufacturer's protocol, and IC50 were generated using a sigmoidal dose-response (variable slope) nonlinear regression curve fit.