Enrolment of older adults with cancer in early phase clinical trials-an observational study on the experience in the north west of England

Abstract

Introduction: older patients represent the majority of cancer patients but are under-represented in trials, particularly early phase clinical trials (EPCTs).

Material and methods: observational retrospective study of patients referred for EPCTs (January-December 2018) at a specialist cancer centre in the UK. The primary aim was to analyse the successful enrolment into EPCTs according to age (<65/65+). The secondary aims were to identify enrolment obstacles and the outcomes of enrolled patients. Patient data were analysed at: referral; in-clinic assessment and after successful enrolment. Among patients assessed in clinic, a sample was defined by randomly matching the older cohort with the younger cohort (1:1) by tumour type.

Results: 555 patients were referred for EPCTs with a median age of 60 years, of whom 471 were assessed in new patient clinics (38% were 65+). From those assessed, a randomly tumour-matched sample of 318 patients (159 per age cohort) was selected. Older patients had a significantly higher comorbidity score measured by ACE-27 (P < 0.0001), lived closer to the hospital (P = 0.045) and were referred at a later point in their cancer management (P = 0.002). There was no difference in suitability for EPCTs according to age with overall 84% deemed suitable. For patients successfully enrolled into EPCTs, there was no difference between age cohorts (20.1 vs. 22.6% for younger and older, respectively; P = 0.675) and no significant differences in their safety and efficacy outcomes.

Discussion: older age did not affect the enrolment into EPCTs. However, the selected minority referred for EPCTs suggests a pre-selection upstream by primary oncologists.

Keywords: early phase; experimental therapies; older cancer patients; phase 1 trials.