Trastuzumab plus pertuzumab for HER2-amplified advanced colorectal cancer: Results from the drug rediscovery protocol (DRUP).

BACKGROUND

In 2-5% of patients with colorectal cancer (CRC), human epidermal growth factor 2 (HER2) is amplified or overexpressed. Despite prior evidence that anti-HER2 therapy confers clinical benefit (CB) in one-third of these patients, it is not approved for this indication in Europe. In the Drug Rediscovery Protocol (DRUP), patients are treated with off-label drugs based on their molecular profile. Here, we present the results of the cohort 'trastuzumab/pertuzumab for treatment-refractory patients with RAS/BRAF-wild-type HER2amplified metastatic CRC (HER2+mCRC)'.

METHODS

Patients with progressive treatment-refractory RAS/BRAF-wild-type HER2+mCRC with measurable disease were included for trastuzumab plus pertuzumab treatment. Primary endpoints of DRUP are CB (defined as confirmed objective response (OR) or stable disease (SD) ≥ 16 weeks) and safety. Patients were enrolled using a Simon-like 2-stage model, with 8 patients in stage 1 and 24 patients in stage 2 if at least 1/8 patients had CB. To identify biomarkers for response, whole genome sequencing (WGS) was performed on pre-treatment biopsies.

RESULTS

CB was observed in 11/24 evaluable patients (46%) with HER2+mCRC, seven patients achieved an OR (29%). Median duration of response was 8.4 months. Patients had undergone a median of 3 prior treatment lines. Median progression-free survival and overall survival were 4.3 months (95% CI 1.9-10.3) and 8.2 months (95% CI 7.2-14.7), respectively. No unexpected toxicities were observed. WGS provided potential explanations for resistance in 3/10 patients without CB, for whom WGS was available.

CONCLUSIONS

The results of this study confirm a clinically significant benefit of trastuzumab plus pertuzumab treatment in patients with HER2+mCRC.

Informations de copyright

Copyright © 2024 The Authors. Published by Elsevier Ltd.. All rights reserved.

Déclaration de conflit d'intérêts

Declaration of Competing Interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests. Derk-Jan A. de Groot received funding for research grants from Siemens and Hoffman-La Roche. All outside the submitted work and all money had been received by the UMCG. Jeanine M.L. Roodhardt is a member of Advisory boards from Bayer, BMS, Merck-Serono, Pierre Fabre, Servier, GSK and Amgen (all paid to institution), received research funding from BMS, Pierre Fabre, Servier, Cleara, Xilis, DoMore diagnostics and HUB organoids B.V. (all paid to institution) and is a Board Member of Foundation Hubrecht Oragnoid Biobank. Liselot Valkenburg-van Iersel reported consulting fees from Sevier, Amgen and Pierre Fabre. Emile E. Voest is founder and current member of the supervisory board of the Hartwig Medical Foundation, independent non-executive director of Sanofi, co-founder of Mosaic Therapeutics, and a board member and founder of the Center for Personalized Cancer Treatment. He has received clinical study grants from Amgen, AstraZenica, BI, BMS, Clovis, Eli Lilly, GSK, Ipsen, MSD, Novartis, Pfizer, Roche and Sanofi, all paid to the Netherlands Cancer Institute. The other authors declare no conflicts of interests.