Clinical and pharmacoeconomic impact of subgroup analysis in onco-hematological patients

Subgroup analysis evaluates a health intervention in subpopulations according to a characteristic or factor. It can be useful for generating new hypotheses or conducting new studies. However, subgroup analysis presents several limitations and it should be considered cautiously. The development of new onco-hematological drugs is accelerating in recent years and the impact of subgroup analysis on clinical decision-making is increasing. The interpretation of subgroup analyses can be controversial in some cases, negatively affecting patients and healthcare systems. This work is a review of the clinical and pharmacoeconomic impact of subgroup analysis in onco-hematological patients. The study describes some illustrative examples of inadequate interpretations about subset analysis: combination of pembrolizumab plus chemotherapy in lung cancer, inhibitors of cyclin-dependent kinases in breast cancer, daratumumab-based regimens in newly diagnosed multiple myeloma, combination of nivolumab with ipilimumab in melanoma and docetaxel in prostate cancer. Subgroup analysis can have a significant impact on the data selection for the development of studies; efficacy, safety, and convenience of treatments in onco-hematological patients; efficiency of therapies in health systems; and therapeutic positioning of antineoplastic drugs. There is a strong need to establish homogeneous criteria for the assessment of subgroup analysis and to develop new tools for its consideration.