Chicago, IL—Reduced-dose chemotherapy is as effective as full-dose chemotherapy in frail elderly patients with advanced gastroesophageal cancer, according to results of the phase 3 GO2 clinical trial presented at the 2019 American Society of Clinical Oncology (ASCO) Annual Meeting. Lower doses of oxaliplatin plus capecitabine (OCap) led to similar survival but improved quality of life compared with higher doses of that regimen in this patient population.
“GO2 is the largest randomized controlled trial to date specifically investigating frail and/or elderly patients with advanced gastroesophageal cancer and results should guide future treatment. The lowest dose tested was noninferior in terms of progression-free survival and produced less toxicity and better overall treatment utility,” said lead investigator Peter S. Hall, MD, PhD, Medical Oncologist, Edinburgh Cancer Centre, Western General Hospital, and Senior Clinical Lecturer, Cancer Informatics, University of Edinburgh Cancer Research Centre, Scotland.
The GO2 Trial
The GO2 trial randomized 514 frail or elderly patients with advanced gastroesophageal cancer unfit for full-dose chemotherapy in a 1:1:1 ratio to 1 of 3 dose levels: level A (oxaliplatin 130 mg/m2 on day 1 every 21 days and capecitabine 625 mg/m2 twice daily on days 1-21); level B (80% of level A doses); or level C (60% of level A doses). After 9 weeks, patients were scored using an Overall Treatment Utility (OTU) tool, which incorporated conventional treatment response assessment, along with tolerability and quality of life, to assess the therapeutic value of the regimens. Treatment continuation was based on clinician judgment.
Grade ≥3 adverse events were reported in 56% of patients treated at level A and B doses but occurred in only 37% of patients treated at the level C dose.
“We hope that our finding helps patients make an informed choice between low-dose chemotherapy and no chemotherapy at all, with the knowledge that low-dose chemotherapy can prove beneficial and still allow them to maintain some quality of life while slowing the progression of the disease,” Dr Hall stated.
Median progression-free survival was 4.9 months with the highest dose of OCap, 4.1 months with an intermediate dose, and 4.3 months with the lowest dose. Median overall survival was 7.5 months at the highest dose level, 6.7 months at the intermediate dose level, and 7.6 months at the lowest dose level.
According to the OTU score, reduced-dose chemotherapy provided the best outcomes. At week 9, good OTU was reported in 35% of patients treated at the highest dose of OCap, 36% of those treated with the intermediate dose, and 43% of those treated at the lowest dose. Poor overall utility was reported in 31%, 38%, and 29% of patients, respectively.
“The OTU tool could represent a new paradigm for how to assess outcomes in older patients with late-stage disease,” Dr Hall said.
ASCO President Weighs In
“Oncologists struggle with a lack of data on elderly frail patients, which represents about 60% of the patients we treat. Only 10% are included in clinical trials. It is wonderful to have real data that will help guide their treatment,” commented ASCO President Monica M. Bertagnolli, MD, FACS, FASCO, at a formal premeeting press cast where data from the GO2 trial were presented.
“‘Less is more’ is becoming a common refrain in some areas of cancer treatment, and one that is paying off for patients’ quality of life. This trial seeks to balance quality of life and increased survival for older and frail people receiving palliative treatment for gastroesophageal cancer, providing data that we sorely need for this patient population. These data are important because they provide a potential new option for patients to slow the progression of disease,” Dr Bertagnolli added.