MedKoo product information:

WZ4002

WZ4002 is EGFR inhibitor against EGFR  T790M (mutation of the gatekeeper T790 residue) which is detected in 50% of clinically resistant patients to gefitinib or erlotinib. WZ4002 has a basic chemical framework (covalent pyrimidine) which is different from that of other EGFR inhibitors.  This agent is 30- to 100-fold more potent against EGFR T790M, and up to 100-fold less potent against wildtype EGFR, than quinazoline-based EGFR inhibitors (HKI-272 and CL-387,785) in vitro. 

WZ4002 is one of three new compounds designed specifically to bind to and inhibit T790M-mutated EGFR. Importantly, WZ4002 does not inhibit wild-type EGFR; thus, it may have less effect on normal body cells and not cause diarrhea or rash like iressa and tarceva. WZ4002 is a compound that can inhibit T790M EGFR in the laboratory cells without inhibiting normal EGFR.  Clinically effective doses could be safely reached in the mice.  This new compound seems sufficiently promising in the lab to move on to phase I testing.  However, as of August 2010, no news about clinical study was reported in the internet.

Researchers tested WZ4002 in NSCLC cells with EGFR T90M and found several that were up to 100 times more potent than quinazolines in restricting cell growth. As an unexpected bonus, these compounds were nearly 100 times less powerful at slowing the growth of cells with normal EGFR, suggesting they would be less likely to produce side effects than current drugs. The agent which performed the best is the pyrimidine WZ4002. (source: http://lcins.org/2009/12/egfr-and-wz4002/).