Lorlatinib

Non-small cell lung cancer (NSCLC) accounts for up to 85% of lung cancer cases worldwide and remains a particularly difficult to treat condition. The gene rearrangement of anaplastic lymphoma kinase (ALK) is a genetic alteration that drives the development of NSCLC in a number of patients. Ordinarily, ALK is a natural endogenous tyrosine kinase receptor that plays an important role in the development of the brain and elicits activity on various specific neurons in the nervous system.

Subsequnetly, lorlatinib is a kinase inhibitor with in vitro activity against ALK and number of other tyrosine kinase receptor related targets including ROS1, TYK1, FER, FPS, TRKA, TRKB, TRKC, FAK, FAK2, and ACK. Lorlatinib demonstrated in vitro activity against multiple mutant forms of the ALK enzyme, including some mutations detected in tumors at the time of disease progression on crizotinib and other ALK inhibitors. Moreover, lorlatinib possesses the capability to cross the blood-brain barrier, allowing it to reach and treat progressive or worsening brain metastases as well. The overall antitumor activity of lorlatinib in in-vivo models appears to be dose-dependent and correlated with the inhibition of ALK phosphorylation.

Although many ALK-positive metastatic NSCLC patients respond to initial tyrosine kinase therapies, such patients also often experience tumor progression. Various clinical trials performed with lorlatinib, however, have demonstrated its utility to effect tumor regression in ALK-positive metastatic NSCLC patients who experience tumor progression despite current use or having already used various first and second-generation tyrosine kinase inhibitors like crizotinib, alectinib, or ceritinib.