Title
Phase II Trial of Early-Line Anti-EGFR Therapy to Facilitate Retreatment for Select Patients with Metastatic Colorectal Cancer

Description
The study will use previously established doses of panitumumab or cetuximab in the metastatic setting for the treatment of unresectable colorectal cancer (CRC). It is designed to investigate an alternative treatment strategy to maximize the benefit to inhibition of epidermal growth factor receptor (EGFR) for a highly selected patient population. It will enroll 110 participants with left-sided, unresectable metastatic CRC. Participants will be on study up to 5 years.

Objective
Primary Objective:
a) Objective response rate for Cohort A
b) Progression free survival for Cohort B

Secondary Objectives:
a) Progression free survival for Cohort A
b) Objective response rate for Cohort B
c) Overall survival for Cohort A and B
d) Toxicity in this treatment setting
e) Rate of retreatment with EGFRi for patients on Arm A

Correlative/Exploratory Objectives:
a) Patient derived cancer organoid response
b) ctDNA over time and at time of progression

Treatment Experimental: Cohort A: No Previous EGFR
Participant who have not be previously exposed to anti-EGFR therapies and are in the first or second-line metastatic treatment setting.
Panitumumab (6mg/kg) or Cetuximab 500mg (per treating physician) on day 1 and 15 of a 28-day cycle

Experimental: Cohort B: Retreatment
Participants with treatment refractory disease who have previously benefitted (greater than or equal to 4 months ago) from anti-EGFR therapy.
Panitumumab (6mg/kg) or Cetuximab 500mg (per treating physician) on day 1 and 15 of a 28-day cycle, +/- Irinotecan (180mg/m^2) every 2 two weeks per standard of care

Key Eligibility For full study eligibility, see this study's ClinicalTrials.gov record.

Applicable Disease Sites
Colon and Rectum

Participating Institutions
UW Health 1 S. Park Medical Center; UW Health Eastpark Medical Center; UW Health University Hospital