Abstract 3482
Background
KRAS oncogene mutations are causing sustained signaling through the mitogen-activated protein kinase (MAPK) pathway resulting in uncontrolled cell growth. Efforts to target KRAS directly or to inhibit downstream effectors have been unsuccessful. Preclinical research revealed that KRAS mutated (KRASm) cells are intrinsically resistant to MEK inhibitors due to upstream growth receptors that reactivate the MAPK and phosphoinositide 3-kinase (PI3K) pathway. Concurrent inhibition of MEK, EGFR and HER2 resulted in synergistic anti-tumor activity, with complete inhibition of tumor growth in vitro and in vivo.
Methods
This is a single-center, phase I dose-escalation study to assess the safety, tolerability and anti-tumor activity of the MEK inhibitor trametinib combined with the dual EGFR/HER2 inhibitor lapatinib in patients with advanced KRASm and PIK3CA wildtype colorectal cancer (CRC), non-small cell lung cancer (NSCLC) and pancreatic cancer. Patients received escalating doses of continuous or intermittent, once daily (QD) orally administered lapatinib and trametinib, starting at 750 mg and 1 mg, respectively. The primary objective was to determine the recommended phase 2 dose (RP2D) and schedule.
Results
Thirty-four patients with CRC (n = 16), NSCLC (n = 15) or pancreatic cancer (n = 3) were enrolled across five dose-levels, 2 patients are still on treatment. Dose-limiting adverse events were reported in twelve patients; grade 3 diarrhea (n = 3), rash (n = 2), nausea (n = 1), several grade 2 toxicities (n = 1) and aspartate aminotransferase elevation (n = 1) resulting in inability to receive 75% of the planned doses (n = 2) or treatment delay (n = 2). The established RP2D was 750 mg lapatinib QD and trametinib 1.5 mg QD 5 days on/2 days off. Out of 22 patients evaluable for response, regression of target lesions was seen in six, with one confirmed partial response in NSCLC. Reductions in pERK and pS6 levels were demonstrated in paired tumor biopsies. Pharmacokinetic results were as expected.
Conclusions
Lapatinib and trametinib could be combined in an intermittent dosing schedule with manageable toxicity. Preliminary signs of anti-tumor activity in NSCLC have been observed with sufficient target engagement.
Clinical trial identification
NCT02230553.
Editorial acknowledgement
Legal entity responsible for the study
The Netherlands Cancer Institute.
Funding
Novartis.
Disclosure
N. Steeghs: Research grant / Funding (institution): AstraZeneca/MedImmune; Research grant / Funding (institution): Bayer; Research grant / Funding (institution): Bristol-Meyers Squibb; Research grant / Funding (institution): Novartis; Research grant / Funding (institution): GlaxoSmithKline; Research grant / Funding (institution): Pfizer; Research grant / Funding (institution): Roche; Research grant / Funding (institution): Genentech/Roche; Research grant / Funding (institution): Boehringer Ingelheim; Research grant / Funding (institution): Blueprint Medicines; Research grant / Funding (institution): AB Science; Research grant / Funding (institution): Deciphera; Research grant / Funding (institution): Genentech; Research grant / Funding (institution): Merck Sharp & Dohme; Research grant / Funding (institution): Amgen; Research grant / Funding (institution): Merus; Research grant / Funding (institution): Lilly; Research grant / Funding (institution): Incyte. K. Monkhorst: Advisory / Consultancy, Speaker Bureau / Expert testimony, Research grant / Funding (institution): Roche; Advisory / Consultancy, Speaker Bureau / Expert testimony, Research grant / Funding (institution): MSD; Advisory / Consultancy, Speaker Bureau / Expert testimony, Research grant / Funding (institution): AstraZeneca; Speaker Bureau / Expert testimony: Benecke; Advisory / Consultancy: Pfizer; Advisory / Consultancy: BMS; Advisory / Consultancy: Abbvie; Advisory / Consultancy: Diaceutics. J.H.M. Schellens: Shareholder / Stockholder / Stock options, and patent holder on oral taxanes: Modra Pharmaceuticals. All other authors have declared no conflicts of interest.
Resources from the same session
4294 - The Patient Voice: An Irish Survey of Nutrition Attitudes & Access to Dietetic Care Throughout the Cancer Journey
Presenter: Erin Stella Sullivan
Session: Poster Display session 1
Resources:
Abstract
1925 - Homcology: home chemotherapy delivery in a simultaneous care project for frail advanced cancer patients
Presenter: Claudio Chini
Session: Poster Display session 1
Resources:
Abstract
4701 - Treatment-related adverse events and tolerability in patients with advanced non-squamous non-small cell lung cancer treated with first-line checkpoint inhibitors in combination with chemotherapy
Presenter: Ruth D'cunha
Session: Poster Display session 1
Resources:
Abstract
2985 - Clinical utility of a systematic toxicity assessment form (STAF) in patients with breast cancer receiving adjuvant or neoadjuvant therapy.
Presenter: Jwa Hoon Kim
Session: Poster Display session 1
Resources:
Abstract
2358 - Physicians’ satisfaction with Health-related quality of life (HRQoL) assessment in daily clinical practice using electronic patient-reported outcome (ePRO) for cancer patients.
Presenter: Guillaume Mouillet
Session: Poster Display session 1
Resources:
Abstract
5172 - Predictors of Survival in Patients with Incurable Cancer
Presenter: Erin Stella Sullivan
Session: Poster Display session 1
Resources:
Abstract
2281 - Patients and Physicians' Satisfaction with Telemedicine (TM) in Cancer Care and Factors that Correlate with a Positive Patient’s Experience
Presenter: Hurria Gondal
Session: Poster Display session 1
Resources:
Abstract
2193 - Adherence to ESMO 2014 guidelines on bone-targeting agent (BTA) initiation for breast and prostate cancer patients: real-world insights from practicing European physicians
Presenter: Alex Rider
Session: Poster Display session 1
Resources:
Abstract
2200 - Use of skeletal-related events preventive agents in patients with solid tumours and bone metastases in central Denmark
Presenter: Anders Boysen
Session: Poster Display session 1
Resources:
Abstract
2504 - Inadequacy of current definition and staging system of Medication-Related Osteonecrosis of Jaw (MRONJ) released by AAOMS : a Computed Tomography study in 151 cancer and myeloma patients
Presenter: Vittorio Fusco
Session: Poster Display session 1
Resources:
Abstract