A phase Ib study of a PI3Kinase inhibitor BKM120 in combination with panitumumab in patients with KRAS wild-type advanced colorectal cancer

Invest New Drugs. 2020 Aug;38(4):1077-1084. doi: 10.1007/s10637-019-00814-3. Epub 2019 Sep 10.


Background Resistance to Epidermal Growth Factor inhibition (EGFRi) in patients with KRAS wild-type (wt) Colorectal Cancer (CRC) may occur as a result of PI3K/AKT/mTOR signaling. We conducted a study to establish the recommended phase II dose (RP2D) and response rate of panitumumab, an EGFRi, plus BKM120, a PI3K inhibitor, in advanced CRC. Methods Patients with chemotherapy refractory KRAS wt CRC, who were EGFRi naive were enrolled. A 3 + 3 dose escalation design was utilized. The starting dose of panitumumab was 6 mg/kg iv every 2 weeks with BKM120 at 60 mg oral daily. Results Nineteen patients were treated and 17 were evaluable for response. The starting dose was not tolerable (mucositis, fatigue). At dose level (DL) 1, three of six patients discontinued treatment due to toxicity, DL - 1 had no significant toxicity. Panitumumab 6 mg/kg iv q 2 weeks with BKM120 60 mg given 5 out of 7 days per week was declared the RP2D. One patient (5.9%) who was PTEN and PIK3CA negative by IHC had a partial response, seven had stable disease, and nine had disease progression. Conclusion Panitumumab (6 mg/kg iv q 2 weeks) with BKM120 60 mg given 5 out of 7 days per week was declared the RP2D. Toxicities including fatigue, rash and mucositis. There was little evidence of activity in this biomarker unselected cohort.

Keywords: BKM120; Metastatic colon cancer; Panitumumab; Phase 1.

Publication types

  • Clinical Trial, Phase I
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aged
  • Aged, 80 and over
  • Aminopyridines / adverse effects
  • Aminopyridines / therapeutic use*
  • Antineoplastic Agents / adverse effects
  • Antineoplastic Agents / therapeutic use*
  • Antineoplastic Combined Chemotherapy Protocols / adverse effects
  • Antineoplastic Combined Chemotherapy Protocols / therapeutic use*
  • Biomarkers, Tumor / metabolism
  • Colorectal Neoplasms / drug therapy*
  • Colorectal Neoplasms / metabolism
  • Exanthema / chemically induced
  • Fatigue / chemically induced
  • Female
  • Humans
  • Male
  • Middle Aged
  • Morpholines / adverse effects
  • Morpholines / therapeutic use*
  • Mucositis / chemically induced
  • PTEN Phosphohydrolase / metabolism
  • Panitumumab / adverse effects
  • Panitumumab / therapeutic use*
  • Phosphatidylinositol 3-Kinases / metabolism
  • Phosphoinositide-3 Kinase Inhibitors / adverse effects
  • Phosphoinositide-3 Kinase Inhibitors / therapeutic use*
  • Proto-Oncogene Proteins p21(ras)


  • Aminopyridines
  • Antineoplastic Agents
  • Biomarkers, Tumor
  • KRAS protein, human
  • Morpholines
  • NVP-BKM120
  • Phosphoinositide-3 Kinase Inhibitors
  • Panitumumab
  • PTEN Phosphohydrolase
  • PTEN protein, human
  • Proto-Oncogene Proteins p21(ras)