ADGRL4 and central nervous system cancer: There are approximately 17 000 new GBM diagnoses every year, increasing the need for new and more effective cancer therapeutics.1 Our group found that polyclonal antibody (pAb) treatments against ELTD1 in orthotropic GL261 and human G55 xenograft glioma pre‐clinical models were successful in decreasing tumour volumes (TV), increasing survival and decreasing microvessel density levels (MVD) when compared to untreated (UT) control.12 However, batch‐to‐batch variabilities as well as potential promiscuity of the pAb posed concerns about specificity as long‐term treatment for patients.