OUP accepted manuscript Academic Article uri icon

abstract

  • Background:Patients with glioblastoma (GBM) have a dismal prognosis. Nearly all will relapse with no clear standard of care for recurrent disease (rGBM). Approximately 50% of patients have tumors harboring epidermal growth factor receptor (EGFR) amplification. The antibody-drug conjugate depatuxizumab mafodotin (depatux-m) binds cells with EGFR amplification, is internalized, and releases a microtubule toxin, killing the cell. Here we report efficacy, safety and pharmacokinetics (PK) of depatux-m + temozolomide (TMZ) in patients with EGFR-amplified rGBM. Methods:M12-356 (NCT01800695) was an open-label study encompassing patients with newly diagnosed or rGBM across 3 treatment arms. Results are reported for adults with EGFR-amplified, measurable rGBM who received depatux-m (0.5-1.5 mg/kg) on days 1 and 15, and TMZ (150-200 mg/m2) on days 1-5 in a 28-day cycle. Patients were bevacizumab and nitrosourea naïve. Results:There were 60 patients, median age 56 years (range, 20-79). Fifty-nine patients previously received TMZ. Common adverse events (AEs) were blurred vision (63%), fatigue (38%), and photophobia (35%). Grades 3/4 AEs were split between ocular and non-ocular AEs, occurring in 22% of patients each. Systemic PK exposure of depatux-m was dose proportional. The objective response rate was 14.3%, the 6-month progression-free survival rate was 25.2%, and the 6-month overall survival rate was 69.1%. Conclusions:Depatux-m + TMZ displayed an AE profile similar to what was described previously. Antitumor activity in this TMZ-refractory population was encouraging. Continued study of depatux-m in patients with EGFR-amplified, newly diagnosed, or recurrent GBM is ongoing in 2 global, randomized trials (NCT02573324, NCT02343406).

authors

  • Lassman, AB
  • Van Den Bent, MJ
  • Gan, HK
  • Reardon, DA
  • Kumthekar, P
  • Butowski, N
  • Lwin, Z
  • Mikkelsen, T
  • Nabors, LB
  • Papadopoulos, KP
  • Penas-Prado, M
  • Simes, J
  • Wheeler, H
  • Walbert, T
  • Scott, AM
  • Gomez, E
  • Lee, HJ
  • Roberts-Rapp, L
  • Xiong, H
  • Ansell, PJ
  • Bain, E
  • Holen, KD
  • Maag, D
  • Merrell, R

publication date

  • January 1, 2019