Chi-Med, AstraZeneca lung cancer drug shrinks resistant tumors

An experimental cancer drug discovered by Hutchison China MediTech has demonstrated promising activity in shrinking tumors in lung cancer patients whose disease had worsened following treatment with approved medicines.

The treatment, which Hutchison China MediTech or “Chi-Med” is developing with AstraZeneca, is one of a new wave of innovative medicines coming out of Chinese research labs as the country flexes its muscles in drug discovery.

Results from small-scale studies presented on Tuesday at a medical meeting in Japan showed that adding savolitinib to either AstraZeneca’s Tagrisso or Iressa improved responses.

Drugs like Tagrisso and Iressa are designed for patients with certain mutations on a gene called EGFR. They can hold disease at bay in these patients but cancer cells often adapt and develop new resistance mechanisms.

Savolitinib is designed to limit their ability to develop such resistance by selectively targeting c-MET, an enzyme that functions abnormally in many tumors.

In one proof-of-concept study, 28 percent of patients with EGFR-mutated advanced non-small cell lung cancer who had previously been treated with Tagrisso showed a partial response with savolitinib.

A second study showed a 31 percent response in patients previously given Iressa.

In cancer medicine a partial response is defined as a reduction of at least 30 percent in the size of measurable tumors.