UCSF

Introduction

Afatinib is an ErbB family receptor inhibitor with efficacy in head and neck squamous cell carcinoma (HNSCC). A phase I trial was conducted to determine the maximally tolerated dose (MTD) of afatinib in combination with carboplatin and paclitaxel as induction chemotherapy (IC).

Material and methods

Patients with newly diagnosed, locally advanced HPV-negative or HPV-positive HNSCC with a significant smoking history were enrolled. Afatinib alone was given daily for two weeks as lead-in and subsequently given with carboplatin AUC 6mg/mlmin and paclitaxel 175mg/m(2) every 21days as IC. Afatinib was started at a dose of 20mg daily and dose escalated using a modified Fibonacci design. After completion of IC, afatinib was discontinued and patients received concurrent cisplatin 40mg/m(2) weekly and standard radiation. Toxicity was assessed using CTCAE version 4.0.

Results

Seven of nine patients completed afatinib lead-in and IC. Five patients had partial response and two patients had stable disease after IC. Dose level 1 (afatinib 20mg) was well tolerated with one grade 3 (ALT elevation) and one grade 4 (neutropenia) toxicities. However, dose level 2 (afatinib 30mg) was not well tolerated with nine grade 3 (pneumonia, abdominal pain, diarrhea, pancytopenia, and UTI), two grade 4 (sepsis) and one grade 5 (death) toxicities.

Conclusions

The MTD of afatinib given with carboplatin AUC 6mg/mlmin and paclitaxel 175mg/m(2) is 20mg daily. Combination of afatinib at doses higher than 20mg with carboplatin and paclitaxel should be administered with caution due to the toxicities.