Abstract 4758
Background
HPV induces many alterations in CDK4-Cyclin D-Rb and apoptotic pathways such as up-regulation of p16, loss of Rb and p53 functions in SCCHN carcinogenesis. Loss of p16 expression is known as a poor prognostic marker in SCCHN for survival. Palbociclib is a highly selective inhibitor of CDK4/6 by blocking Rb phosphorylation with radiosensitizing activity in preclinical studies. Addition of palbociclib to cetuximab and IMRT provides a strong rationale to improve efficacy of treatment in locally advanced SCCHN, especially in p16/HPV-negative tumour.
Methods
This is a phase I study designed to determine the maximum tolerated dose (MTD) and toxicity of palbociclib, cetuximab, and IMRT, using a classical 3 + 3 design (NCT03024489). The study included locally advanced SCCHN of oral cavity, oropharynx, larynx, and hypopharynx. Palbociclib dose was escalated with 3 dose levels (DLs), starting from 75 to 125 mg/d orally for 21 day-on and 7 day-off for 2 cycles. For all DLs, cetuximab was administered at 400 mg/m2IV on day -7 and then 250 mg/m2weekly for 7 weeks. IMRT was delivered 5 day-on and 2 day-off with a total dose of 70 Gy for 33 fractions. MRI and PET scans pre- and post-treatment was used to evaluate preliminary efficacy.
Results
A total of 13 eligible patients were enrolled in the dose escalation cohort. No MTD was observed. One DLT, febrile neutropenia (FN) was reported in 1 of 7 patients who received 125 mg of palbociclib (DL3) at the 6thweek of IMRT. The FN recovered without G-CSF support within 7 days after discontinuation of palbociclib. Overall, toxicities were related to cetuximab and IMRT. Complete response was observed in 7 of 10 evaluable patients (70%), while overall objective response was demonstarted in 9 of 10 patients (90%).
Conclusions
The recommended phase 2 dose was palbociclib 125 mg/d for 21 days on and 7 days off with full standard dose of cetuximab and IMRT for locally advanced SCCHN. MTD was not achieved. The combination was well tolerated with promising preliminary efficacy. The expansion cohort of palbociclib 125 mg/d is currently accruing up to 15 locally advanced p16-negative SCCHN patients.
Clinical trial identification
NCT#03024489.
Editorial acknowledgement
Legal entity responsible for the study
The authors.
Funding
Pfizer.
Disclosure
N. Ngamphaiboon: Honoraria (self), Advisory / Consultancy, Speaker Bureau / Expert testimony, Research grant / Funding (institution), Travel / Accommodation / Expenses: Roche; Honoraria (self), Advisory / Consultancy, Speaker Bureau / Expert testimony, Research grant / Funding (institution): AstraZeneca; Honoraria (self), Speaker Bureau / Expert testimony, Travel / Accommodation / Expenses: Eisai; Honoraria (self), Advisory / Consultancy, Speaker Bureau / Expert testimony, Travel / Accommodation / Expenses: Amgen; Honoraria (self), Advisory / Consultancy, Speaker Bureau / Expert testimony, Research grant / Funding (institution), Travel / Accommodation / Expenses: MSD; Honoraria (self), Advisory / Consultancy, Speaker Bureau / Expert testimony: Novartis; Advisory / Consultancy: Boehringer Ingelheim; Travel / Accommodation / Expenses: Merck; Travel / Accommodation / Expenses: Taiho. T. Siripoon: Travel / Accommodation / Expenses: Pfizer; Travel / Accommodation / Expenses: Roche; Travel / Accommodation / Expenses: Boehringer Ingelheim. S. Lukerak: Research grant / Funding (institution): Pfizer; Research grant / Funding (institution): MSD; Research grant / Funding (institution): AstraZeneca. N. Sankaseam: Research grant / Funding (institution): Roche; Research grant / Funding (institution): MSD; Research grant / Funding (institution): AstraZeneca. E. Sirachainan: Honoraria (self), Travel / Accommodation / Expenses: MSD; Honoraria (self): Sanofi/Aventis; Honoraria (self): Merck; Honoraria (self), Travel / Accommodation / Expenses: Amgen; Honoraria (self), Travel / Accommodation / Expenses: Roche; Travel / Accommodation / Expenses: Mundipharma; Honoraria (self), Research grant / Funding (institution), Travel / Accommodation / Expenses: AstraZeneca; Honoraria (self): LF Asia; Honoraria (self): Diethelm Keller Logistics; Honoraria (self): BMS; Honoraria (self): Boehringer Ingelheim. All other authors have declared no conflicts of interest.
Resources from the same session
3252 - Genes involved in DNA replication, chromatin remodeling and cell cycle as potential biomarkers for therapy outcome to immune therapy in patients with metastatic cutaneous malignant melanoma
Presenter: Fernanda Costa Svedman
Session: Poster Display session 3
Resources:
Abstract
5545 - Phase Ib/II Study (SENSITIZE) assessing safety, pharmacokinetics (PK), pharmacodynamics (PD), and clinical outcome of domatinostat in combination with pembrolizumab in patients with advanced melanoma refractory/non-responding to prior checkpoint inhibitor therapy
Presenter: Jessica Hassel
Session: Poster Display session 3
Resources:
Abstract
5213 - Genomic landscape of primary malignant melanoma of esophagus
Presenter: Jie Dai
Session: Poster Display session 3
Resources:
Abstract
2716 - A phase III, randomised, double-blind study of adjuvant cemiplimab versus placebo post-surgery and radiation in patients with high-risk cutaneous squamous cell carcinoma (CSCC)
Presenter: Danny Rischin
Session: Poster Display session 3
Resources:
Abstract
3550 - ILLUMINATE 301: A randomized phase 3 study of tilsotolimod in combination with ipilimumab compared with ipilimumab alone in patients with advanced melanoma following progression on or after anti-PD-1 therapy
Presenter: Marcus Butler
Session: Poster Display session 3
Resources:
Abstract
1645 - PRIME002 - Early phase II study of Azacitidine and Carboplatin priming for Avelumab in patients with advanced melanoma who are resistant to immunotherapy
Presenter: Andre Van Der Westhuizen
Session: Poster Display session 3
Resources:
Abstract
4440 - Pembrolizumab (pembro) Plus Lenvatinib (len) for First-Line Treatment of patients (pts) With Advanced Melanoma: Phase 3 LEAP-003 Study
Presenter: Alexander Eggermont
Session: Poster Display session 3
Resources:
Abstract
3454 - Proof of concept study with the histone deacetylase inhibitor vorinostat in patients with resistant BRAFV600 mutated advanced melanoma
Presenter: Sanne Huijberts
Session: Poster Display session 3
Resources:
Abstract
1832 - A phase Ia/Ib clinical study to evaluate the safety, pharmacokinetics (PK) and preliminary anti-tumor activity of FCN-159 in patients with advanced melanoma harboring NRAS-aberrant (Ia) and NRAS-mutation (Ib).
Presenter: Lu Si
Session: Poster Display session 3
Resources:
Abstract
3996 - A Phase I Clinical Trial Investigating the Therapeutic Cancer Vaccine UV1 in Combination with Pembrolizumab as First-Line Treatment of Patients with Malignant Melanoma
Presenter: Sanjiv Agarwala
Session: Poster Display session 3
Resources:
Abstract