Importantly, (R)-ND336 exhibits marginal to no inhibition of several other MMPs (Figure 6A), including MMP8, which has been shown to possess anti-tumor activity; and ADAM proteases whose inhibition was at the root of a musculoskeletal syndrome associated with pan-MMP inhibitors that contributed to the discontinuation of clinical trials of these drugs.43 Finally, (R)-ND336 was chosen for its ability to effectively cross the blood brain barrier (BBB). The gene discussed is MMP8; the disease is neoplasm.