Safety and Efficacy of Pembrolizumab (MK-3475) Plus Binimetinib Alone or Pembrolizumab Plus Chemotherapy With or Without Binimetinib in Metastatic Colorectal Cancer (mCRC) Participants (MK-3475-651/KEYNOTE-651)

200 mg Pembrolizumab solution for IV infusion Q3W

tablet orally BID at 30 or 45 mg depending upon DLT profile

85 mg/m\^2 as IV infusion. Administered Q2W as part of mFOLFOX7 cocktail. Dose may be de-escalated to 70 mg/m\^2 if the standard dose of mFOLFOX7 is deemed too toxic per mTPI, based upon occurrence of DLTs.

400 mg/m\^2 as IV infusion. Administered Q2W as part of mFOLFOX7 or FOLFIRI cocktail, depending upon allocation.

2400 mg/m\^2 over 46-48 hours as IV infusion. Administered Q2W as part of mFOLFOX7 or FOLFIRI cocktail, depending upon allocation. Dose may be de-escalated to 2000 mg/m\^2 if the standard dose of mFOLFOX7 or FOLFIRI is deemed too toxic per mTPI, based upon occurrence of DLTs.

180 mg/m\^2 as IV infusion. Administered Q2W as part of FOLFIRI cocktail. Dose may be de-escalated to 150 mg/m\^2 if the standard dose of FOLFIRI is deemed too toxic per mTPI, based upon occurrence of DLTs.