Antibody drug conjugates in older patients: State of the art.

More than half of cancer cases occur in patients aged 65 years or older. The efficacy and safety of antibody drug conjugates (ADCs) in older patients remains an unclear subject as available evidence is limited. Geriatric population is underrepresented in clinical trials. Consequently, most of our knowledge regarding innovative therapeutics was studied on a younger population. In this review of published literature, we report the available information on efficacy, safety and pharmacokinetics of FDA approved ADCs for hematologic malignancies and solid tumors in the geriatric population. We explore the results of clinical trials dedicated for older individuals as well as subgroup analyses of the geriatric population in major trials evaluating these drugs. Available data suggest a similar efficacy in older adults as compared to general population. However, older patients might be prone to a higher rate of adverse events in incidence with a potential impact on quality of life. We lack data to support primary dose reductions or schedule modifications in this category of patients. No pharmacokinetic differences were reported between age groups. It is crucial to encourage the development of clinical trials dedicated to older patients with geriatric parameters (G8 score, G-CODE…) so that results can be more representative of this population outside of clinical trials.

Evidence for Treatment-by-Biomarker interaction for FDA-approved Oncology Drugs with Required Pharmacogenomic Biomarker Testing.

For oncology drugs that were approved by the US Food and Drug Administration (FDA) and required pharmacogenomic biomarker testing, we describe 1) the use of enrichment (biomarker-positive patients) and a randomized controlled design by pre-approval trials and 2) the treatment-by-biomarker interaction. From the 137 drugs included in the FDA table, we selected the 22 oncology drugs with required genetic testing in their labels. These drugs corresponded to 35 approvals supported by 80 clinical studies included in the FDA medical officer reviews of efficacy. For two thirds of approvals (24/35, 69%), all clinical studies were restricted to biomarker-positive patients (enriched). Among the 11 remaining approvals with at least one non-enriched trial, for five approvals, the non-enriched studies were non-randomized. The treatment-by-biomarker interaction was statistically significant for three approvals and missing for two. Among the six approvals with a non-enriched randomized controlled trial, three featured a statistically significant treatment-by-biomarker interaction (p < 0.10), for an enhanced treatment effect in the biomarker-positive subgroup. For two thirds of FDA approvals of anticancer agents, the requirement for predictive biomarker testing was based on clinical development restricted to biomarker-positive patients. We found only few cases with clinical evidence that biomarker-negative patients would not benefit from treatment.