A Phase 1, First-in-Human Study to Evaluate the Safety, Tolerability, Pharmacokinetics and Pharmacodynamics of IMGN853 in Adults With Ovarian Cancer and Other FOLR1-Positive Solid Tumors

Trial ID # NCT01609556
Phase I
Drug Class Antibody (and other Targeted) Drug Conjugates: FRalpha
Drug Name Mirvetuximab Soravtansine
Alternate Drug Names M9346A-sulfo-SPDB-DM4, IMGN853, Anti-FOLR1-mab Maytansinoid Conjugate
Drugs in Trial Mirvetuximab Soravtansine
Eligible Participant

FRalpha-positive platinum-resistant cancer; ≤ 5 prior therapies; IHC: ≥ 25% tumor cells at ≥ 2+ intensity

Patients Enrolled

205 (46 ovarian)

Therapy Setting

Recurrence

Study Design

Open-Label, Non-randomized

Endpoints

RP2D, ORR, PFS, evaluated per RECIST

Biomarkers

FRalpha protein

Efficacy

RP2D: 6.0mg/kg q3w
ORR: 26% (1CR, 11PR, n=46)
PFS: 4.8 months (3.9-5.7)

Exploratory analysis # of prior therapies:
>3 previous therapies (n=23): ORR: 13%; PFS: 3.9 months (2.6-5.4)
≤3 previous therapies (n=23): ORR: 39%; PFS: 6.7 months (3.9-8.7)

Exploratory analysis FORWARD I criteria:
ORR: 47% (n=37); PFS: 6.7 months (4.1-8.3)

Clinically Significant Adverse Events

Serious AE: overall (22%)
Grade 3-4 AE: any (26%)
41% of patients experienced low grade ocular AEs

Conclusion

Promising activity in platinum-resistant FRalpha-positive patients

Reference

Moore KN et al. Safety and Activity of Mirvetuximab Soravtansine (IMGN853), a Folate Receptor Alpha-Targeting Antibody-Drug Conjugate, in Platinum-Resistant Ovarian, Fallopian Tube, or Primary Peritoneal Cancer: A Phase I Expansion Study. J Clin Oncol (2017) 35(10):1112-1118
https://www.ncbi.nlm.nih.gov/pubmed/28029313

Moore KN et al. Mirvetuximab soravtansine (IMGN853), a folate receptor alpha (FR⍺)-targeting antibody-drug conjugate (ADC), in platinum-resistant epithelial ovarian cancer (EOC) patients (pts): Activity and safety analyses in phase I pooled expansion cohorts. J Clin Oncol (2017) 35 (suppl; abstr 5547)
http://abstracts.asco.org/199/AbstView_199_190120.html